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Background: Difficulties in the treatment of purulent wounds are caused by bacterial biofilms, which results in decontamination limitations. Infected wounds are not sufficiently susceptible to existing antibiotics, necessitating the search for alternative approaches to reduce the concentration of pathogenic microflora. Methods: This study describes an approach to the effective treatment of wounds by photodynamic inactivation or therapy (PDI/PDT) of antibiotic-resistant microflora under fluorescence control. For this purpose, laser and LED light (660–680 nm) and different groups of photosensitizers (PS) (1% solutions of methylene blue, aluminum phthalocyanine, chlorine e6 and nanocomposites containing these groups of PS) were used. The study included 90 patients with various wounds. Some patients were subjected to fluorescence diagnosis by laser spectral analysis before the PDT. Results: Positive results were achieved in 76 patients (84%, p < 0.05). After the first PDT session, a decrease in the concentration of microflora was noticeable. By the third and seventh days, a significant to complete inactivation of bacteria was obtained. In all patients who were photo-diagnosed before PDT, a significant PS concentration decrease of more than 75% after PDT was obtained. Conclusion: PDT is an effective method for the inactivation of antibiotic-resistant pathogens, including in long non-healing wounds, contributing also to early tissue regeneration. [ABSTRACT FROM AUTHOR]

Background: Difficulties in the treatment of purulent wounds are caused by bacterial biofilms, which results in decontamination limitations. Infected wounds are not sufficiently susceptible to existing antibiotics, necessitating the search for alternative approaches to reduce the concentration of pathogenic microflora. Methods: This study describes an approach to the effective treatment of wounds by photodynamic inactivation or therapy (PDI/PDT) of antibiotic-resistant microflora under fluorescence control. For this purpose, laser and LED light (660–680 nm) and different groups of photosensitizers (PS) (1% solutions of methylene blue, aluminum phthalocyanine, chlorine e6 and nanocomposites containing these groups of PS) were used. The study included 90 patients with various wounds. Some patients were subjected to fluorescence diagnosis by laser spectral analysis before the PDT. Results: Positive results were achieved in 76 patients (84%, p < 0.05). After the first PDT session, a decrease in the concentration of microflora was noticeable. By the third and seventh days, a significant to complete inactivation of bacteria was obtained. In all patients who were photo-diagnosed before PDT, a significant PS concentration decrease of more than 75% after PDT was obtained. Conclusion: PDT is an effective method for the inactivation of antibiotic-resistant pathogens, including in long non-healing wounds, contributing also to early tissue regeneration.

Spectroscopic approaches are very good to noninvasively determine the most significant indicators of the tissue state. Indocyanine green (ICG) is a well-known fluorescent dye approved for clinical applications, which has a short circulation time in the vascular system and low photostability. At high temperatures the molecular solution of the photosensitizer self-assembles into a stable J-aggregate form of ICG nanoparticles (ICG NPs) with the absorption peak in the near-infrared range. Investigation of ICG NP stability in human blood and plasma using a fiber-spectroscopic system demonstrates no difference in absorption properties and different dependence of the integrated fluorescence ratio between ICG monomers and J-aggregates in blood and plasma. Transition of ICG NP aggregates to the monomeric form in human blood plasma results in a higher circulation time of the fluorescent dye in the vascular system. High stability of aggregates and a low elimination rate may increase efficiency of fluorescent diagnostics of near-tumor tissues. [ABSTRACT FROM AUTHOR]

Photodynamic therapy (PDT) is an effective treatment option for the treatment of superficial basal cell carcinoma (sBCC). Recent publications have demonstrated that PDT with 7.8% 5‐aminolaevulinic acid nanoemulsion‐based gel (BF‐200 ALA‐PDT) is an effective and safe alternative for the treatment of sBCC). To investigate the efficacy and safety of 7.8% 5‐aminolaevulinic acid nanoemulsion‐based gel (BF‐200 ALA)‐PDT for the treatment of sBCC. A non‐controlled, open‐label single centre study was conducted. Patients received one PDT cycle with two PDT sessions one‐week apart. In case that clinical‐dermoscopy evaluation of treatment outcome revealed remaining lesions, a second PDT cycle was performed. The clinical results at the dermoscopy and fluorescence diagnosis level were histologically confirmed in all patients. Treatment response was evaluated 3, 6, and 12 months after last PDT session. A total of 31 patients (12 men and 19 women), with a median age of 63.74 years were included in this study. 3‐month after PDT‐session, 23/31 patients were complete responders (74.19%) after two BF‐200 ALA ‐PDT sessions. Esthetic outcome was considered good‐to‐excellent. 5 Aminolevulinic acid 7.8% nanoemulsion‐based gel (BF‐200 ALA) PDT is an effective therapy option for the treatment of sBCC. Complete clearance rates were higher in those patients who received only one PDT cycle. These results show a similar tendency as shown in other publications. [ABSTRACT FROM AUTHOR]

The study demonstrates the ability of fluorescence diagnosis to perform intraoperative analysis of the bladder wall. The data of 10 patients with superficial bladder cancer who underwent PDD with the use of the fluorescence video system with excitation wavelenght in the "red" wavelength range and TUR is discussed. General condition of the bladder is assessed, the main foci of the tumor are determined. Then a tumor resection is performed. Further examination and identification of the fluorescing boundaries of the tumor remaining after TUR is performed to make a decision of a re‐resection. In addition, small fluorescing tumor foci, not detected with WL cystoscopy, are detected. Moreover the diagnostic fluorescence contrast is measured, allowing quantitative assessment of the 5‐ALA accumulation in tissues. The applied laser wavelength of 635 nm allows the light to penetrate deeper into the bladder tissue, making it possible to detect tumors including in the deeper layers. [ABSTRACT FROM AUTHOR]

This article describes a video endoscopy system intended for fluorescence‐based imaging of the tracheobronchial tree in the visible (VIS) and near‐infrared (NIR) regions of the spectrum. This system helps acquire both fluorescence images (VIS/NIR) and a white‐light image of the same area and has been developed on the basis of a standard bronchofiberscope with several diode lasers used as the light sources to excite Vis and NIR, the white‐light source, and photodynamic irradiation. A multimodal video system forms images and gives the possibility to perform targeted photodynamic therapy and control the dose of light irradiation through assessing the degree of photobleaching.The system capability is illustrated through clinical examples. The paper describes the procedure for photodynamic theranostics with chlorin e6 in patients with central lung cancer. The possibility of additional accurate localization of tumor lesions and their borders with NIR imaging is shown; to acquire a NIR image, a common dose of indocyanine green (ICG) used in angiography was administered to patients during the examination. It is also demonstrated that the same lesions can be identified using a combination of two dyes: chlorin e6 + ICG. [ABSTRACT FROM AUTHOR]

• Fluorescence Diagnosis with violet excitation • Contrast enhancement methods • Contrast can be increased by Red/Green and Red–Green methods • Ambient light suppression by time-resolved subtraction from the fluorescence frame • Endogenous fluorescence is suppressed by contrast enhancement methods Two Bispectral contrast enhancement approaches for the fluorescence diagnosis with chlorine-e6 and a wide field-of-view imaging system with fluorescence excitation at 405 nm and time-resolved background suppression were analyzed and compared. Two techniques for the contrast enhancement of a fluorescent video system (Red/Green (R/G) ratio and Red-Green (R-G)) with time-resolved background suppression for fluorescent diagnosis (FD) were tested in four patients with basal cell carcinoma (BCC). The results of both contrast enhancement methods were compared for the diagnostic efficiency for FD of BCC. Both techniques successfully determined the boundaries of the lesions and the fluorescence intensity. Both contrast enhancement modes have proven effective in identifying tumor borders in cases of low contrast in BCC FD with Ce6. While the Red/Green (R/G) mode provides sharper lesion borders, the Red minus Green (R-G) mode visualizes more fluorescent features and makes it easier to assess the lesion margins. [ABSTRACT FROM AUTHOR]

Objective: This study is to analyze fluorescence sensitivity in the diagnosis of brain and spinal cord tumors.Material and methods: The authors conducted a multicenter retrospective analysis of data on 653 cases in 641 patients: 553 of them had brain tumors and 88 spinal cord tumors. Brain tumor resection was performed in 523 patients, of whom 484 were adults and 39 children. The analyzed series was presented by 320 gliomas, 101 meningiomas, and 72 metastases. A stereotactic biopsy was performed in 20 patients and endoscopic surgery in 10 patients. In all cases, 20 mg/kg of 5–Aminolaevulinic acid was administered orally 2-h before surgery. All surgical interventions were performed with a microscope BLUE 400 to visualize fluorescence, while endoscopic surgery—with an endoscope equipped with a fluorescent module. Fluorescence spectroscopy was conducted in 20 cases of stereotactic biopsies and in 88 cases of spinal cord tumors.Results: Among adult brain tumors operated by microsurgical techniques, meningiomas showed the highest 5-ALA fluorescence sensitivity 94% (n = 95/101), brain metastases 84.7% (n = 61/72), low-grade gliomas 46.4% (n = 26/56), and high-grade gliomas 90.2% (n = 238/264). In children the highest 5-ALA visible fluorescence was observed in anaplastic astrocytomas 100% (n = 4/4) and in anaplastic ependymomas 100% (n = 4/4); in low-grade gliomas it made up 31.8% (n = 7/22). As for the spinal cord tumors in adults, the highest sensitivity was demonstrated by glioblastomas 100% (n = 4/4) and by meningiomas 100% (n = 4/4); Fluorescence was not found in gemangioblastomas (n = 0/6) and neurinomas (n = 0/4). Fluorescence intensity reached 60% (n = 6/10) in endoscopic surgery and 90% (n = 18/20) in stereotactic biopsy.Conclusion: 5-ALA fluorescence diagnosis proved to be most sensitive in surgery of HGG and meningioma (90.2 and 94.1%, respectively). Sensitivity in surgery of intracranial metastases and spinal cord tumors was slightly lower (84.7 and 63.6%, correspondingly). The lowest fluorescence sensitivity was marked in pediatric tumors and LGG (50 and 46.4%, correspondingly). Fluorescence diagnosis can also be used in transnasal endoscopic surgery of skull base tumors and in stereotactic biopsy.

The therapeutic properties of 5-aminolevulinic acid (5-ALA) have been extensively studied for cancer detection and treatment using photodynamic therapy (PDT). When administered externally, 5-ALA is converted to protoporphyrin IX (PpIX) in cancer cells, which generates reactive oxygen species (ROS) upon exposure to light. This process enables targeted cell death induction and cancer detection. Given the highly conserved nature of heme biosynthesis over billions of years, we hypothesized that natural mechanisms might exist to prevent excessive accumulation of PpIX or heme resulting from 5-ALA overload. Therefore, we anticipated alterations in protein expression profiles upon exogenous administration of 5-ALA. To understand cellular responses to 5-ALA, we investigated protein expression changes and identified OR1B1 as a promising target in bladder, prostate, lung, and cervical cancer cells. OR1B1 expression was observed only with 5-ALA and ferrous chloride, highlighting the central role of heme in this discovery. Immunofluorescence and electron microscopy confirmed OR1B1's sub-cellular localization. These findings suggest that 5-ALA transformation in cancer cells and OR1B1 expression have potential for enhancing cancer detection and developing alternative treatments, including immunotherapy. This approach overcomes the limitations of PDT and opens new avenues for effective and targeted cancer interventions. • This paper represents first complete proteomic analysis of the effects on cancer cells following exposure to 5-aminolevulinic acid (5-ALA). • 5-ALA triggers the down- or upregulation of >100 proteins. • Upon the analysis of significantly upregulated proteins, OR1B1 stands out, showing significant and specific upregulation following 5-ALA treatment without light with respect to its expression at the cellular membrane. • Heme and not protoporphyrin IX triggers the expression of OR1B1. • OR1B1 is a potential target for other imaging or treatment modalities in combination with 5-ALA. [ABSTRACT FROM AUTHOR]

• Fluorescence diagnosis with violet and red excitation provide comparable contrast. • Contrast can be increased by division of the red channel by green channel. • Background illumination is suppressed by time-resolved subtraction from the fluorescence frame. • Endogenous fluorescence is suppressed by division of the red channel to the green one. Fluorescence diagnostics with two different wide field-of-view imaging systems with fluorescence excitation at 405 nm and 635 nm, respectively, were compared. Both systems include fluorescence quantification and experimental geometry normalization algorithms. A newly developed system with an excitation wavelength of 405 nm was tested on intralipid fluorescent tumor phantoms with chlorin-e6. Both, this new system and a second existing system with an excitation wavelength of 635 nm, were used for fluorescent diagnosis in six patients with basal cell carcinoma and cancer of the oral mucosa. For PDT, a red diode laser with a wavelength of 660 nm was used for all 6 patients. One patient received an additional irradiation using the red LED source of the new system The boundaries of the lesions and the fluorescence intensity were successfully determined by both video systems. Both fluorescence imaging approaches showed comparable contrast between diseased and healthy tissues. For oral mucosal cancer, a system with violet fluorescence excitation, bispectral frame analysis, and time-resolved background suppression showed better contrast between the tumor and normal tissue and effective elimination of autofluorescence. Moreover, both systems provided efficient quantification of fluorescence and gave fluorescence indices that were weakly dependent on the distance between the device and the tissue. [ABSTRACT FROM AUTHOR]

Biophotonics and laser medicine are very dynamic and continuously increasing fields ecologically as well as economically. Direct communication with medical doctors is necessary to identify specific requests and unmet needs. Information on innovative, new or renewed techniques is necessary to design medical devices for introduction into clinical application and finally to become established after positive clinical trials as well as medical approval. The long-term endurance in developing light based innovative clinical concepts and devices are described based on the Munich experience. Fluorescence technologies for laboratory medicine to improve non-invasive diagnosis or for online monitoring are described according with new approaches in improving photodynamic therapeutic aspects related to immunology. Regarding clinically related thermal laser applications, the introduction of new laser wavelengths and laser parameters showed potential in the treatment of varicose veins as well as in lithotripsy. Such directly linked research and development are possible when researchers and medical doctors perform their daily work in immediate vicinity, thus have the possibility to share their ideas in meetings by day. [ABSTRACT FROM AUTHOR]

The purpose of this review is to compile preclinical and clinical results on phthalocyanines (Pcs) as photosensitizers (PS) for Photodynamic Therapy (PDT) and contrast agents for fluorescence imaging. Indeed, Pcs are excellent candidates in these fields due to their strong absorbance in the NIR region and high chemical and photo-stability. In particular, this is mostly relevant for their in vivo activation in deeper tissular regions. However, most Pcs present two major limitations, i.e., a strong tendency to aggregate and a low water-solubility. In order to overcome these issues, both chemical tuning and pharmaceutical formulation combined with tumor targeting strategies were applied. These aspects will be developed in this review for the most extensively studied Pcs during the last 25 years, i.e., aluminium-, zinc- and silicon-based Pcs.

Oral cancer is among the most common malignancies worldwide, therefore early detection and treatment is imperative. The 5-year survival rate has remained at a dismal 50% for the past several decades. The main reason for the poor survival rate is the fact that most of the oral cancers, despite the general accessibility of the oral cavity, are not diagnosed until the advanced stage. Early detection of the oral tumors and its precursor lesions may be the most effective means to improve clinical outcome and cure most patients. One of the emerging technologies is the use of non-invasive in vivo tissue imaging to capture the molecular changes at high-resolution to improve the detection capability of early stage disease. This review will discuss the use of optical probes and highlight the role of optical imaging such as autofluorescence, fluorescence diagnosis (FD), laser confocal endomicroscopy (LCE), surface enhanced Raman spectroscopy (SERS), optical coherence tomography (OCT) and confocal reflectance microscopy (CRM) in early oral cancer detection. FD is a promising method to differentiate cancerous lesions from benign, thus helping in the determination of adequate resolution of surgical resection margin. LCE offers in vivo cellular imaging of tissue structures from surface to subsurface layers and has demonstrated the potential to be used as a minimally invasive optical biopsy technique for early diagnosis of oral cancer lesions. SERS was able to differentiate between normal and oral cancer patients based on the spectra acquired from saliva of patients. OCT has been used to visualize the detailed histological features of the oral lesions with an imaging depth down to 2–3 mm. CRM is an optical tool to noninvasively image tissue with near histological resolution. These comprehensive diagnostic modalities can also be used to define surgical margin and to provide a direct assessment of the therapeutic effectiveness.

Background The establishment of a precise and rapid method to detect metastatic lymph nodes (LNs) is essential to perform less invasive surgery with reduced gastrectomy along with reduced lymph node dissection. We herein describe a novel imaging strategy to detect 5-aminolevulinic acid (5-ALA)-induced protoporphyrin IX (PpIX) fluorescence in excised LNs specifically with reduced effects of tissue autofluorescence based on photo-oxidation of PpIX. We applied the method in a clinical setting, and evaluated its feasibility. Methods To reduce the unfavorable effect of autofluorescence, we focused on photo-oxidation of PpIX: Following light irradiation, PpIX changes into another substance, photo-protoporphyrin, via an oxidative process, which has a different spectral peak, at 675 nm, whereas PpIX has its spectral peak at 635 nm. Based on the unique spectral alteration, fluorescence spectral imaging before and after light irradiation and subsequent originally-developed image processing was performed. Following in vitro study, we applied this method to a total of 662 excised LNs obtained from 30 gastric cancer patients administered 5-ALA preoperatively. Results Specific visualization of PpIX was achieved in in vitro study. The method allowed highly sensitive detection of metastatic LNs, with sensitivity of 91.9% and specificity of 90.8% in the in vivo clinical trial. Receiver operating characteristic analysis indicated high diagnostic accuracy, with the area under the curve of 0.926. Conclusions We established a highly sensitive and specific 5-ALA-induced fluorescence imaging method applicable in clinical settings. The novel method has a potential to become a useful tool for intraoperative rapid diagnosis of LN metastasis. [ABSTRACT FROM AUTHOR]

Background The preferential accumulation of 5-aminolaevulinic acid (ALA)-induced protoporphyrin IX (PpIX) in neoplastic cells supports its potential use in the photodetection of epithelial tumours through porphyrin fluorescence. Objective To assess the validity of fluorescence diagnosis (FD) as an efficient pre-surgical in vivo imaging tool for defining the lateral boundaries of various types of basal cell carcinomas (BCCs). Methods The BCC tumour area was determined for 27 patients using FD digitalized imaging system, where the accumulation of PpIX in tumour tissue in relation to normal tissue was measured. Subsequently, BCCs were excised according to the complete area defined by FD using Mohs micrographic surgery (MMS). Results Of the 27 BCCs, the FD margin of the lesion coincided with the histopathological picture in 12 BCCs (44.44%). The mean value of accumulation factor (AF) was 2.7. Although 17 pigmented BCCs showed attenuated or absent fluorescence in the center, fluorescence at their periphery was used as a guide for excision, and statistically, the pigmentation of the BCCs showed no effect on the results of the FD efficacy ( p = 1.0). Conclusion Fluorescence diagnosis of BCC may be beneficial as a guide to the safety margin needed before MMS. The safety margin is decided according to the FD tumour diameter in relation to the clinical tumour diameter. [ABSTRACT FROM AUTHOR]

We have studied the feasibility of using an indotricarbocyanine dye as a marker for the efficacy of photodynamic therapy (PDT) of cancers with the photosensitizer Photolon. We have established that on exposure to laser emission at λ = 667 nm with an exposure dose of 100 J/cm, we observe that the Photolon concentration drops by about a factor of two in the exposed part of the tumor, while the concentration of the indotricarbocyanine dye does not change in any region of the tumor node. We have observed a correlation between the change in the shape of the fluorescence spectra of the indotricarbocyanine dye in vivo in the 780-880 nm resulting from a PDT session with the photosensitizer Photolon and the extent of damage to the tumor tissues. Changes in the shape of the fluorescence spectrum of the dye are interpreted in terms of a model involving the appearance of absorption by different forms of hemoglobin, and changes in their ratio in the exposed part of the tumor due to consumption of molecular oxygen. [ABSTRACT FROM AUTHOR]

Purpose Overexpression of epidermal growth factor receptor (EGFR) is observed in oral squamous cell carcinoma (OSCC) and is associated with increased proliferation, metastasis and therapeutic resistance. We aim to develop a novel drug delivery system comprised of a photosensitizer Chlorin e6 (Ce6) that is encapsulated in a viral envelope and tagged with anti-EGFR antibody to target OSCC. Methods Ce6 was encapsulated in both virosomes (Ce6-Vir) and virosomes tagged with anti-EGFR antibody (Ce6-Vir-EGFR′). In vitro studies were conducted to assess the cellular uptake and bioavailability of the photosensitizer in OSCC cells. Ce6 alone or in constructs was then administered in a hamster cheek pouch model and fluorescence imaging and spectroscopy was performed. Results In vitro results showed that the uptake of Ce6-Vir-EGFR′ was lower than that for Ce6-Vir and Ce6 possibly due to its large size. Nevertheless, in vivo results showed significant tumor specificity of Ce6-Vir-EGFR′ compared to Ce6. The tumor to normal mucosa ratio showed that Ce6-Vir-EGFR′ can successfully target OSCC lesions and therefore shows potential for use in fluorescence diagnosis of OSCC. Conclusions Both the virosome-Ce6 constructs were internalized by OSCC cells and successfully used for fluorescence imaging. Tagging with anti-EGFR antibody further improved the targeting ability toward OSCC. [ABSTRACT FROM AUTHOR]

The review is devoted to methods of targeted chemical modifications of bacteriochlorophyll a. These methods provide an approach to the synthesis of derivatives with improved photophysical properties and increased hydrophilicity and are suited to the design of conjugates with other biologically active molecules utilized for fluorescence diagnosis and binary cancer therapy. [ABSTRACT FROM AUTHOR]

Diseases are often accompanied by abnormal expression of gaseous signaling molecules including nitric oxide (NO), carbon monoxide (CO), and hydrogen sulfide (H 2 S). Sensing these gaseous markers is thus important for identification and investigation of pathological processes. In contrast to conventional approaches, such as electrochemical, chromatographical methods, etc., optical imaging shows merits including high sensitivity, good spatiotemporal resolution, and ideal selectivity. Especially, optical molecular probes with aggregation-induced emission (AIE) properties have good potential for bio-detection since they show maintained optical signals in the aggregated state. Recently, many AIE molecular probes have been developed for imaging disease-related gaseous signaling molecules. Generally, these probes recognize the analytes through turn-on or ratiometric approaches. This review summarizes the recent progress in organic probes with AIE properties for sensing gaseous markers and relative disease diagnosis applications. Based on the types of analytes, the probes are divided into three groups: NO, CO and H 2 S sensors. Molecular designs and sensing mechanisms of these AIE probes are highlighted. Their gaseous signaling molecules detection applications at cellular and animal levels are presented. Finally, some existing problems and future promising development directions are discussed with the hope to inspire further developments of AIE probes for precise disease diagnosis. [ABSTRACT FROM AUTHOR]

Background Basal cell carcinoma ( BCC) is the most frequent malignant tumor of the skin. The high prevalence of BCC, the risk of local recurrence, and the difficult clinical identification of the excision margins emphasize the importance of studying new approaches, ensuring complete surgical excision that allows preservation of normal tissue, especially for BCCs located on cosmetically important areas such as the mid face. Photodiagnosis ( PD) is a pre-operative technique that allows a more accurate distinction of neoplastic lesions from surrounding healthy skin in vivo. Purpose The aim of this study is to assess the usefulness of PD for the evaluation of tumor margins in 10 patients with recurrent BCC of the face. Methods We study the red fluorescence emitted by neoplastic tissue under a Wood's lamp irradiation, after accumulation of methyl amino levulinate ( MAL) cream in 10 patients with recurrent BCC. Results Our histologic analysis of perilesional skin by PD allowed to delineate more precise tumor margins, thus achieving radical excision in 90% of patients. Conclusion PD represents a diagnostic method that helps to distinguish between tumor tissue and surrounding healthy tissue especially in case of recurrent BCC of the face when the clinical delimitation is not clear. [ABSTRACT FROM AUTHOR]

Summary Background Monitoring of tumor burden during mycosis fungoides (MF) treatment, is crucial to adjust therapy accordingly. This is usually achieved through combined by clinical assessment with histopathological and immunohistochemical evaluation. Aim To assess the validity of fluorescence diagnosis (FD) in the measurement of response to therapy in early MF, using in comparison flow cytometric technique of skin biopsies for CD4+/CD7− malignant T-cell count before and after therapy. Patients and Methods Twenty-two patients of histologically proven early MF (stages Ia, Ib, IIa) were subjected to fluorescence diagnosis of their most affected skin lesion before and after 12 weeks of phototherapy with or without combination therapy. In comparison flow cytometric assessment of skin biopsies for CD4+/CD7− malignant T-cell count was evaluated before and after therapy from skin biopsy of the same lesion. Results All tested MF lesions showed varying degrees of fluorescence by FD at week zero, with a mean accumulation factor (AF), which is the fluorescence ratio between the tumor tissue and normal skin, of 2.2. After 12 weeks of therapy, the mean AF showed significant reduction to 1.94 ( p = 0.009). The percent of CD4+/CD7− cells dropped significantly after treatment ( p = 0.029). No correlation between CD4+/CD7− cell counts and the mean AF could be deduced. Conclusion In cases of mycosis fungoides, fluorescence diagnosis can represent an effective tool for evaluating the response to therapy. Changes in accumulation factor values can be used for follow-up of therapy in the same patient, but it should not be used as an absolute value. [ABSTRACT FROM AUTHOR]

Pigmented basal cell carcinoma (PBCC) occurs more frequently in Asian population. The efficacy of fluorescence diagnosis (FD) for PBCCs treated with Mohs micrographic surgery has not yet been determined. This study enrolled 255 patients with 258 biopsy-proven BCC lesions: 199 PBCCs (77.1%) and 59 non-PBCCs (22.9%). We compared the clinicopathological and surgical features of the PBCCs and non-PBCCs. Each group was divided into 2 sub-groups, those assessed and not assessed by FD, to retrospectively analyse surgical features. Aggressive histological subtypes were less prevalent in PBCCs than in non-PBCCs. PBCCs required significantly fewer stages of Mohs excision, with significantly smaller surgical margins and surgical depth, than non-PBCCs. FD did not confer any benefits on PBCCs during Mohs micrographic surgery. However, non-PBCCs assessed by FD required significantly fewer Mohs stages, with significantly smaller surgical margins, than lesions not assessed by FD. These findings suggest that FD should be performed before Mohs micrographic surgery to delineate the margins of non-PBCCs in Asians. [ABSTRACT FROM AUTHOR]

Summary: Background: As carcinogenesis is often accompanied by inflammation, fluorescence diagnosis (FD) of tumours reportedly leads to false positive results. However, an influence of inflammation on the efficiency of photodynamic therapy (PDT) is not known. Objective: Therefore we investigated whether LPS-induced expression of the pro-inflammatory cytokine interleukin-6 (IL-6) influences hypericin and protoporphyrin IX (PpIX) accumulation, and their photocytotoxicity. As in vitro models served normal and malignant human skin cell lines. Additionally we analyzed whether low-dose photodynamic treatment as found during FD and sublethal PDT could modulate the expression of IL-6 and other cytokines as low-dose PDT has the potential for treatment of inflammatory skin diseases. Methods: Cells were pre-incubated with LPS to induce a pro-inflammatory milieu. Photosensitizer accumulation and toxicity were measured by a microplate reader, IL-6 via Sandwich ELISA and the other cytokines via a Multiplex Immunoassay. Results and conclusions: Neither hypericin uptake nor PpIX accumulation was influenced by the proinflammatory state. The false positive classification in FD of patients could rather be due to sensitizer-loaded immune cells. On the other hand, low dose PDT is able to significantly reduce the level of IL-6 in all cell lines. Under differing PDT-conditions, PDT can enhance IL-6 in malignant cells, which could elicit a specific anti-tumour immune response. Furthermore, hypericin alone is able to up-regulate the anti-inflammatory cytokines IL-4, -5 and -10, which could be useful to reduce excessive inflammation. LPS-induction has no additional influence in most cases. Some of these findings could contribute to abate inflammatory diseases on skin or promote wound healing. [Copyright &y& Elsevier]

Background: Lymph node metastasis is one of the most critical prognostic factors in patients with colorectal cancer. Although regional lymph nodes should be surgically resected and pathologically examined, techniques for the intraoperative diagnosis of lymph node metastasis remain to be well established. Fluorescence diagnosis using 5-aminolevulinic acid (5-ALA) is a promising technique for evaluating various malignancies. After exogenous administration of 5-ALA, protoporphyrin IX (PPIX) accumulates in malignant cells and can be detected as red fluorescence. In this study, we investigated the usefulness of fluorescence diagnosis using 5-ALA for the detection of lymph node metastasis in a mouse model of colon cancer. Materials and Methods: An orthotopic colon cancer model was prepared by inoculating the cecal wall of nude mice with HCA7, a human colon adenocarcinoma cell line. After 3 wk, 40 mg/kg of 5-ALA was administered intraperitoneally (IP) or orally (PO). Fluorescence diagnosis with a D-Light System (Karl Storz) was then performed after 3 or 6 h. Results: In the IP group, PPIX fluorescence was detected in metastatic lymph nodes as well as in other malignant lesions, including primary tumors and abdominal implantations, while non-metastatic nodes were fluorescence-negative. In contrast, no obvious fluorescence was detected in cancerous tissues in the PO group. Conclusions: PPIX fluorescence induced by intraperitoneal injection of 5-ALA allows metastatic lymph nodes to be accurately diagnosed in this mouse model. This technique may facilitate the intraoperative diagnosis of lymph node metastases from colon cancer in a clinical setting. [ABSTRACT FROM AUTHOR]

OBJECTIVE Conventional thoracoscopy, routinely performed in patients with pleural diseases, is not always conclusive in staging of pleural spread. Fluorescence diagnosis (FD) with 5-aminolaevulinic acid (5-ALA) has been used in the diagnostic purpose for various malignancies. The impact of fluorescence thoracoscopy on diagnosis and staging of pleural malignancies was examined. METHODS A total of 23 patients with non-conclusive pleural effusions were enrolled in the prospective single-institution trial. Eligible patients were administered 25 mg/kg of 5-ALA (‘Alasense’, Niopik, Russian Federation) per os 3 h before video-assisted thoracoscopy. After conventional inspection with white light, thorough fluorescence investigation of the visceral and parietal pleura was performed (D-LIGHT Auto Fluorescent System, Karl Storz, Germany). Biopsy specimens of both normal and abnormal sites, as determined from white-light and FD inspection, were obtained for histological examination. RESULTS There was no morbidity or mortality due to the procedure. A definitive diagnosis was obtained in all cases: malignant mesothelioma in 13 cases, other malignancies (pleural metastases) in 8 cases and non-specific inflammation in 3 patients. A total of 118 biopsy specimens were available for histological examination. In 20 patients, all pleural deposits (n = 60) detected by white-light thoracoscopy had bright red fluorescence during FD and were proved to be malignant. Upstaging occurred in 12 patients (57.2%) (unsuspected 21 tumour deposits) due to FD examination. Micrometastases of macroscopically normal pleura were detected, only by FD, in one patient. Comparing the results of histological examination of specimens detected by conventional thoracoscopy with that by fluorescence thoracoscopy, we obtained 82 true positive, 10 false-negative, 23 true negative, 3 false-positive results with a specificity of 88.4%, sensitivity of 89.1% and diagnostic accuracy of 88.9%. CONCLUSIONS FD using 5-ALA in the pleural cavity is a feasible diagnostic tool when used in addition to white-light thoracoscopy. It improves visualization of additional lesions or even micrometastases in patients with pleural malignancy. [ABSTRACT FROM AUTHOR]

Summary: Background and objective: To evaluate the usefulness and feasibility of fluorescence examination and photodynamic therapy (PDT) for facial squamous cell carcinoma. Methods: A 68-year-old male patient underwent 3 courses of PDT. The first treatment was carried out using topically applied 5-aminolevulinic acid (ALA) to the affected area (5.0cm×2.5cm) 3h before light irradiation. ALA/PpIX-mediated fluorescence was used to visualize the lesion and its margin. The lesion was illuminated with a 630nm laser at 120J/cm2. Thirty days later, the residual lesion received the second treatment at the same light dose after topical use of ALA. Despite the tumor was treated with two courses of PDT, The lesion was not cleared completely yet. At last we used topical ALA and intravenous injection of HiPorfin, with the same light dose, then the lesion was cured and the patient was tumor-free followed up for over 15 months. Results: ALA/PpIX-mediated fluorescence visualized the lesion location. Complete cure was achieved after the third course of ALA/Hiporfin PDT. During the 15 months of followed up, no recurrence was noticed. Conclusion: ALA assisted fluorescence examination can be a useful tool to visualize the malignant lesion and determine its margin. ALA-PDT is effective for superficial lesions, but for thicker and deeper lesions, systemic administration of photosensitizer is indispensable. [Copyright &y& Elsevier]

The purpose of this review is to compile preclinical and clinical results on phthalocyanines (Pcs) as photosensitizers (PS) for Photodynamic Therapy (PDT) and contrast agents for fluorescence imaging. Indeed, Pcs are excellent candidates in these fields due to their strong absorbance in the NIR region and high chemical and photo-stability. In particular, this is mostly relevant for their in vivo activation in deeper tissular regions. However, most Pcs present two major limitations, i.e., a strong tendency to aggregate and a low water-solubility. In order to overcome these issues, both chemical tuning and pharmaceutical formulation combined with tumor targeting strategies were applied. These aspects will be developed in this review for the most extensively studied Pcs during the last 25 years, i.e., aluminium-, zinc- and silicon-based Pcs. [ABSTRACT FROM AUTHOR]

Abstract: Objectives and aims: Laser therapy for penile carcinoma is commonly used despite high recurrence rates of up to 48%. The aim of our study was to investigate the long-term recurrence rate of patients treated by fluorescence-guided laser therapy for penile carcinoma and its impact on oncologic outcome. Patients and methods: Between 1999 and 2005, a total of 26 patients with premalignant carcinoma in situ (Tis) (n = 11) or invasive penile carcinoma (n = 15) were treated by fluorescence-guided laser therapy in our center. The mean follow-up was 71.1 months (range 41–104 months). Recurrence rate, time to recurrence, and impact on survival was investigated for Tis patients and penile carcinoma patients separately. Results: No patient died tumor-associated recurrence during follow-up. No local progression of T stage was observed in patients with Tis tumor. In the group with invasive penile cancer, there were 4 (15.4%) local recurrences. However, 3 of them occurred after more than 3 years and, therefore, are more likely to be considered as “de novo” carcinoma. No intra- or perioperative side effects of photodynamic diagnosis (PDD) were observed. Conclusions: Local recurrence rate of laser therapy can be reduced by fluorescence guidance without impairing cosmetic or functional results. The necessary equipment is available in many centers that perform PDD for urothelial bladder cancer. PDD, therefore, can be considered to be cost-effective and easy to perform. Prospective multi-center studies to directly compare recurrence rates between white light and fluorescence-guided laser therapy for penile carcinoma are required. [Copyright &y& Elsevier]

Oral cancer is among the most common malignancies worldwide, therefore early detection and treatment is imperative. The 5-year survival rate has remained at a dismal 50% for the past several decades. The main reason for the poor survival rate is the fact that most of the oral cancers, despite the general accessibility of the oral cavity, are not diagnosed until the advanced stage. Early detection of the oral tumors and its precursor lesions may be the most effective means to improve clinical outcome and cure most patients. One of the emerging technologies is the use of non-invasive in vivo tissue imaging to capture the molecular changes at high-resolution to improve the detection capability of early stage disease. This review will discuss the use of optical probes and highlight the role of optical imaging such as autofluorescence, fluorescence diagnosis (FD), laser confocal endomicroscopy (LCE), surface enhanced Raman spectroscopy (SERS), optical coherence tomography (OCT) and confocal reflectance micr scopy (CRM) in early oral cancer detection. FD is a promising method to differentiate cancerous lesions from benign, thus helping in the determination of adequate resolution of surgical resection margin. LCE offers in vivo cellular imaging of tissue structures from surface to subsurface layers and has demonstrated the potential to be used as a minimally invasive optical biopsy technique for early diagnosis of oral cancer lesions. SERS was able to differentiate between normal and oral cancer patients based on the spectra acquired from saliva of patients. OCT has been used to visualize the detailed histological features of the oral lesions with an imaging depth down to 2-3 mm. CRM is an optical tool to noninvasively image tissue with near histological resolution. These comprehensive diagnostic modalities can also be used to define surgical margin and to provide a direct assessment of the therapeutic effectiveness. [ABSTRACT FROM AUTHOR]

Hemangioblastoma is a benign tumor of the cerebellum, and treatment involves surgical excision, both as the initial treatment and also in case of recurrence. Recurrence of hemangioblastoma can be local due to incomplete resection or can be distant and separate from the tumor resection region. Local recurrence can largely be avoided by verifying for any residual tumor intraoperatively before closure. In this study, we used intraoperative fluorescent diagnosis using 5-aminolevulinic acid (5-ALA) to verify the presence of a residual tumor during surgical resection. Nine patients with hemangioblastoma were given 1 g of 5-ALA orally before surgery, and a laser beam of 405 nm was focused on the tumor during resective surgery. Fluorescence of protoporphyrin IX (PPIX) was observed in the core of tumor in all the cases. Fluorescence of PPIX was observed in the peritumoral cyst wall in two patients after tumor resection, and in both of them fluorescent parts of PPIX were resected and histological examination showed tumor cells. Usually, there are no tumor cells in the peritumoral cyst of a hemangioblastoma, yet hemangioblastomas may sometimes recur from an unresected cyst wall. It is thus necessary to excise an infiltrating cyst of tumor cells to prevent recurrence. Intraoperative fluorescent diagnosis using 5-ALA is a useful method to discern whether tumor cells are present in the peritumoral cyst wall of a hemangioblastoma. [ABSTRACT FROM AUTHOR]

Summary: Background: Methyl-aminolevulinate photodynamic therapy (MAL-PDT) is a successful treatment for non-melanoma skin cancers in the UK. Monitoring the photobleaching of the photosensitiser, protoporphyrin IX (PpIX) during treatment has been demonstrated to indicate the efficacy of the treatment. This study investigated photobleaching during light irradiation. Methods: A validated non-invasive fluorescence imaging system was utilised to monitor changes in PpIX fluorescence during light irradiation. Fifty patients were recruited to this study, with patients monitored before, during (forty patients at the half way stage and ten at regular intervals in the initial phase of treatment) and after light irradiation. Results: Phased PpIX photobleaching was observed during light irradiation with a significantly greater change (P <0.001) in PpIX photobleaching during the first half of light treatment. Within the ten patients monitored periodically the phased photobleaching observed fitted a double exponential decay curve (r 2 =0.99, P <0.005) suggesting a rapid initial phase of reaction when the light treatment was commenced. Conclusions: Photobleaching was observed to be maximal in the initial phases of treatment, however photobleaching of PpIX continued until the completion of light treatment indicating that current clinical protocols for MAL-PDT do not over-treat the lesion with light. [ABSTRACT FROM AUTHOR]

Background: Psoriasis lesions accumulate protoporphyrin IX (PpIX) with a variable distribution within plaques due to variations in hyperkeratosis causing differences in penetration of cream or light. Objectives: To study the effects of different keratolytic pretreatments in PpIX-induced fluorescence diagnosis (FDAP) and during photodynamic therapy (PDT). Methods: Two psoriasis plaques of 10 patients were treated with either topical retinoic acid or with a hydrocolloid dressing. The hydrocolloid dressing gave the best results. Subsequently, two different contralateral plaques of eight patients were pretreated with a hydrocolloid dressing or the standard pretreatment, salicylic acid in petrolatum, during the 6 weeks of PDT. Biopsies were investigated with respect to stratum corneum thickness, proliferation, differentiation and inflammation. Results: Irritation and point bleedings were noticed after retinoic acid. A hydrocolloid dressing induced the best clinical improvement. Therefore, it was used as alternative pretreatment for psoriasis prior to PDT. We observed significant clinical and immunohistochemical improvement of psoriasis in the salicylic acid as well as the hydrocolloid dressing pretreated plaques. Conclusions: Salicylic acid in petrolatum and a hydrocolloid dressing prior to FDAP and PDT induce improvement of hyperkeratosis. Thus, a hydrocolloid dressing is a good alternative to the current keratolytic pretreatment regime. [ABSTRACT FROM AUTHOR]

Background Basal cell carcinoma (BCC) is the most common malignant skin carcinoma. Fluorescence diagnosis (FD) has been suggested as a promising method for noninvasive detection of subclinical tumour cell dissemination in BCC. Objectives In this prospective study, we evaluated the clinical performance of a preoperative definition of the lateral borders of BCC by FD in comparison with its definition by purely clinical diagnosis (CD). The fluorescence intensity on the skin was recorded using a digital light-emitting diode-based fluorescence imaging system. Methods Twenty-six patients with BCC (22 with nodular subtype) of the H-zone were included. The tumour area was determined 3 h after application of methyl aminolaevulinate by inspection and photographic documentation (CD) and FD. Subsequently, BCCs were excised according to the complete area defined by CD and FD with a security margin of 3 mm; surgical specimens were sectioned horizontally and subjected to meticulous histological mapping. The tumour areas as determined by FD, CD and histology were superimposed to map the entire lateral tumour margin. Results The tumour area could be visualized by FD in 24 of 26 patients. The mean tumour area as determined by FD was significantly smaller than the tumour area as determined by CD [80 mm2, 95% confidence interval (CI) 50–110 mm2 vs. 101 mm2, 95% CI 76–125 mm2; P < 0·012]. The superimposition of FD and histology showed in 10 of 26 patients a complete detection of the tumour margin by FD; thus sensitivity of FD was calculated as 38·5%. In only three of 26 patients FD revealed a tumour extent greater than determined by CD. Specificity of FD was calculated as 88·4%. Conclusions On aggregate, this study suggests that preoperative FD of nodular BCC localized in the H-zone offers no additional benefit to define subclinical tumour infiltration compared with CD alone. [ABSTRACT FROM AUTHOR]

Background: Diagnosis of oral cancer is conventionally carried out using white light endoscopy and histopathology of biopsy samples. However, oral tumours are mostly superficial and the lesion and its margins can be difficult to visualise under white light. We present clinical data on fluorescence diagnostic imaging of oral lesions using hypericin, a plant-based photosensitiser.Methods: Fluorescence images of lesions and normal tissue were captured using an endoscope after hypericin administration. The images were analysed to extract their colour parameters, which, along with the red-to-blue intensity ratios, were analysed and used to discriminate between tissue types. The results were correlated with those from histopathology.Results: The red-to-blue intensity ratio increased from normal to hyperplastic to cancerous tissue and was a good parameter to discriminate between these tissue types, with sensitivity and specificity levels of 90% and above.Conclusion: Our results show that hypericin fluorescence imaging has the potential to be used for the clinical diagnosis of oral cancer. Further study to enhance the clinical potential of this technique includes the development of a real-time image processing and analysis system interfaced to the endoscope to enable same-day cancer diagnosis and demarcation of lesion margins in a clinical setting. [ABSTRACT FROM AUTHOR]

Fluorescence diagnosis (FD) seems to be a promising method for the non-invasive detection of tumour boundaries. We aimed to investigate the diagnostic performance of conventional FD of basal cell carcinoma (BCC). Patients were included in this study when they had a skin lesion on the head which was clinically consistent with the diagnosis of BCC. FD was performed using a 20% 5-aminolaevulinic acid (ALA) cream. The FD tumour area was determined 3.5 h after the ALA application using the naked eye and a Wood lamp. The tumour margins were marked on the basis of FD. The lesions were then excised according to the FD-defined tumour margin. On histology, the tumour margins were checked whether the lesion was completely excised in accordance with FD. Twenty-eight BCCs were finally included into the statistical analysis. In six BCCs, the FD-defined BCC margin did not correlate with the histopathologically assessed tumour borders. Four of these lesions were incompletely excised; two tumours were excised in toto indicating that the tumour was beyond the FD-defined margin but not at the excision margin. Hence, the rate of incompletely excised BCCs was 14.3% (4/28). The sensitivity and specificity rates of FD were 79 and 100%, respectively. FD is pretty sensitive and highly specific in regard to the demarcation of BCC margins. When compared to clinically based BCC excision, however, FD does not appear to be substantially superior to simple clinical assessment of tumour margins. [ABSTRACT FROM AUTHOR]

Abstract: Fluorescence diagnosis (FD) and photodynamic therapy (PDT) are modern methods which are evaluated in different fields in gynecology. FD is under investigation as a method gynecological conditions such as cervical intraepithelial neoplasia (CIN), vulvar intraepithelial neoplasia (VIN), endometriosis and ovarian cancer. PDT is being evaluated in a multicentric randomized phase-II study for the treatment of human papillomavirus (HPV)-associated CIN using topical hexaminolevulinate (HAL). Furthermore, PDT of VIN and genital warts has shown promising results. The aim of this review is to give an overview of the current applications in diseases of the lower genital tract, especially of CIN, VIN and HPV-related genital warts (condylomata acuminata). [Copyright &y& Elsevier]

Bladder cancer is a common disease with a high recurrence rate. In order to improve the treatment of superficial bladder tumors, we evaluated the efficacy and safety of transurethral resection (TURB) followed by fluorescence diagnosis (FD) and photodynamic therapy (PDT) with chlorin e6 photosensitizers (PSs), viz. "Fotoran e6" and "Fotoditazin". It was found that both PSs generated singlet oxygen and revealed moderate affinity toward the lipid-like compartment. Between November 2018 and October 2020, 12 patients with verified non-muscle invasive bladder cancer (NMIBC) were treated by TURB combined with FD and PDT. Eight patients received "Fotoran e6" intravenously, while four patients received intravesical PSs. The patient ages were between 31 and 79 years, with a median age of 64.5 years (mean 61.3 ± 14.2). The total light dose was 150 J/cm2 for the local irradiation of the tumor bed with a red light at the λ = 660 nm wavelength, and 10–25 J/cm2 were additionally delivered for diffuse irradiation of the entire bladder mucosa. At the median follow-up period of 24 months (mean 24.5 ± 5.4 months, range 16–35 months), 11 patients remained tumor-free. One 79-year-old patient developed a recurrence without progression to the muscle layer. This pilot study shows that the TURB + FD + PDT technique is an effective and safe option for the first-line treatment of superficial bladder tumors. [ABSTRACT FROM AUTHOR]

We have determined the influences of polyvinylpyrrolidone (PVP) on the topical delivery of chlorin e6 (Ce6) in malignant bladder cells. The chick chorioallantoic membrane (CAM) was used to model the tumor spheroids that resemble small residual bladder tumors prior to vascularization. Macroscopic fluorescence imaging showed that Ce6-PVP-induced fluorescence had a higher sensitivity and specificity for delineating tumor from the adjacent normal CAM compared to Ce6 alone. Nonlinear regression analyses have shown that Ce6-PVP has a longer half-life in the tumor compared to Ce6. The uptake ratio of Ce6-PVP was found to have a 2-fold increase across the CAM when compared to that of Ce6, indicating that PVP was able to facilitate diffusion of Ce6 across the membrane. Confocal laser scanning microscopy further confirmed that Ce6-PVP has better penetration in the CAM as well as in the tumor cells compared to Ce6. The present work contributes to our understanding of the Ce6-PVP drug-polymer system by demonstrating for the first time that the presence of PVP facilitates the transport of Ce6 across the chorioallantoic membrane. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Abstract: An improved formulation of the photosensitizer chlorin e6 (Ce6) in combination with the hydrophilic polymer polyvinylpyrrolidone (PVP) was investigated for its potential clinical applications in fluorescence diagnosis and photodynamic therapy (PDT) of cancer. This study reports the comparative preclinical biodistribution and efficacy of Ce6 delivered with or without PVP versus dimethyl sulfoxide (DMSO). The safety and fluorescence pharmacokinetics of Ce6–PVP in humans was also accessed. Biodistribution results showed that Ce6–PVP had higher tumor to normal tissue ratio compared to the other formulations. The sensitivity and specificity derived from the area under the receiver operating characteristics curves showed that the formulations were able to discriminate tumor from peritumoral muscle in the following order: Ce6–PVP>Ce6>Ce6–DMSO. In vitro PDT results showed that Ce6–PVP was found to induce selective phototoxicity in leukemic cells compared to peripheral mononuclear blood cells. In addition, in vivo light irradiation at 1h after Ce6–PVP was found to induce greater tumor necrosis without causing animal toxicity. In patients, preferential accumulation of Ce6–PVP was observed in angiosarcoma lesions compared to normal skin following intravenous administration. In conclusion, PVP significantly enhanced the Ce6 concentration in tumors compared with Ce6 alone and increased the therapeutic index of PDT without any side effects in animal model. No serious adverse events were observed in human as well. [Copyright &y& Elsevier]

Abstract: Fluorescence diagnosis following oral administration of 5-aminolevulinic acid (5-ALA) has shown to enable the sensitive visualization of intestinal metaplasia, dysplasia and early carcinoma in Barrett''s esophagus. Once being established, this technique will be a potential alternative to today''s standard diagnosis, i.e. four-quadrant random biopsies which are taken every 1–2 cm of the esophagus for histopathological analysis. In order to further improve this methodology, topical application of lipophilic 5-ALA esters to the esophagus could be advantageous in terms of fluorescence contrast and fluorescence intensity in the target tissue, adverse side effects, as well as application time. Therefore, the aim of this study was to develop a bioadhesive formulation loaded with hexylaminolevulinate (HAL) targeting the esophageal lining. In the present study, different mucoadhesive gels including poloxamer 407, cross-linked polyacrylic acid, hydroxypropylmethylcellulose, sodium carboxymethylcellulose and chitosan have been evaluated with respect to bioadhesion to the esophagus using an ex vivo rat model and a clinical study on healthy volunteers. In order to visualize the mucoadhesive properties of the formulations, a blue dye was incorporated as contrast agent. Chitosan has shown the best esophageal adhesion both in vitro and in vivo. Furthermore, using the in vitro release profiles from chitosan loaded with 40 mM of HAL, one can estimate that after a residence time of 10 min on the esophageal wall, the amount of HAL delivered to the epithelium will be sufficient to perform fluorescence diagnosis of Barrett''s esophagus following swallowing of this formulation. [Copyright &y& Elsevier]

The concept of intraoperative in vivo diagnosis and selective resection of infiltrated lymph nodes in ovarian cancer has not been evaluated despite the increased morbidity associated with pelvic and paraaortic lymph node dissection and its questionable therapeutic value. Fluorescence photodetection is based on the application of a photosensitizer relatively selective for malignant tissue, which after light activation of appropriate wavelength, shows fluorescence. Six hours after oral application of 10 mg/kg body weight 5-aminolevulinic acid, the abdominal cavity of a patient with suspicion of recurrent ovarian cancer was inspected using a laparoscope and blue light at 380-440 nm. Spectral measurements at a wavelength of 635 nm, multiple peritoneal biopsies, and lymph node excisions were performed. White light inspection and porphyrin fluorescence photodetection revealed no intraperitoneal metastases and multiple biopsies were negative. Fluorescence-positive lymph nodes were visible only in the left common iliac region and a specific porphyrin fluorescence peak could be detected. In contrary, no increased porphyrin fluorescence of intraperitoneal tissues or skin was seen. Fluorescence microscopy showed the characteristic red fluorescence in the infiltrated parts of the lymph node tissue by the papillary ovarian cancer. Histology of the other sites was negative. No systemic or cutaneous side effects were recorded. This data is a proof of the concept that porphyrin fluorescence-guided lymph node metastasis detection is possible in ovarian cancer and should stimulate further research in this field. [ABSTRACT FROM AUTHOR]

Summary: Generation of singlet oxygen and estimation of its lifetime, the oxygen effect, the subcellular localization of photosensitizers and their photodegradation during photodynamic therapy (PDT), the effects of PDT on DNA and chromosomes were described in the first part of our review. In this review we discuss PDT in combination with other treatments (hyperthermia, ionizing radiation, electrotherapy, chemotherapeutic drugs) or with other agents; cell interactions and bystander effects in PDT; the influence of PDT on the cytoskeleton; a novel technology, named photochemical internalisation (PCI), for light-induced delivery of macromolecules and 5-aminolevulinic acid (ALA) PDT. Lipophilic derivatives of ALA, instead of ALA itself, were proposed for induction of protoporphyrin IX (PpIX) in the treatment of superficial lesions. Based on this research a Norwegian company PhotoCure ASA was founded in 1993 with the aim to commercialise photodynamic technologies developed at the Norwegian Radium Hospital, the largest comprehensive cancer centre in Northern Europe. The company has two products on the market: Metvix® for treatment of basal cell carcinomas and actinic keratoses, and Hexvix® for fluorescence diagnosis of bladder cancer. New ALA derivatives for fluorescence diagnosis and treatment of early-stage cancers in internal organs, e.g. colon cancer, are currently being investigated. [Copyright &y& Elsevier]

Abstract: Formulations of hypericin (HY) with plasma protein have been conventionally used, but to date, no alternative pharmaceutical formulation has been developed for clinical use. Previously, it was reported that formulation of HY containing a biocompatible solvent and penetration enhancer, N-methyl pyrrolidone (NMP) was found to be effective for the delivery of HY across in vivo chick chorioallantoic membrane (CAM). This present study reports further investigations on the HY-NMP formulations in CAM implanted with human bladder cancer cells as a potential fluorescence diagnostic agent of cancer. The conventional formulation of HY (HY-HSA 0.5%) was included as control. The red-to-blue (I(R)/I(B)) intensity ratio of fluorescence images was used as a diagnostic algorithm, to differentiate the uptake of HY between tumor and adjacent regions on CAM. Results indicated that HY-NMP 0.05% was significantly better than HY-HSA 0.5%. The findings of the I(R)/I(B) ratios between tumor and adjacent tissues, indicated the potential of using NMP as an alternative to plasma protein in clinical fluorescence diagnosis with HY. The NMP formulations investigated were able to produce significantly higher contrast for tumor tissues and at earlier time points than was possible with HY-HSA 0.5%. [Copyright &y& Elsevier]

Abstract: The use of fluorescence diagnosis as a modern cancer diagnostic modality is rapidly gaining importance in the field of urology. It is based on the detection of distinctive light emission of tissues sensitized by fluorescent dyes, commonly referred to as photosensitizers, after irradiation with a specific light source. Therefore, the search for specific fluorescent dyes with high sensitivity and specificity for bladder cancer is constantly being sought after. The aim of this study is to investigate the use of a new formulation consisting a mixture of chlorin e6 and polyvinylpyrrolidone (Ce6–PVP) for the detection of human bladder cancer cells (MGH) implanted on the chick chorioallantoic membrane (CAM) model. Uptake kinetics studies were quantitatively determined for both systemic and topical administrations of Ce6–PVP to the normal CAM as well as the MGH human bladder tumor implanted on CAM using fluorescence imaging technique. Rapid elimination of Ce6–PVP was displayed following topical application compared to systemic administration in the normal CAM system. Ce6–PVP was found to localize selectively in the xenografted bladder tumor in contrast to the CAM tissue. Neither dark toxicity nor irritancy was observed on the CAM tissue at the dose of 2 mg/kg Ce6–PVP. In conclusion, the Ce6–PVP formulation appeared to have the potential as a fluorescent marker for fluorescence diagnosis of human bladder cancer. [Copyright &y& Elsevier]

Objective: This study was undertaken to evaluate the feasibility of autofluorescence laparoscopy in the diagnosis of endometriotic lesions. Study design: Prospective analysis of 83 consecutive patients undergoing laparoscopy for suspected endometriosis under white light illumination and autofluorescence diagnosis, the study measured total number of endometriotic lesions diagnosed under white light illumination and with autofluorescence diagnosis. Results: The biopsy-based sensitivity of white light diagnosis alone and white light illumination and autofluorescence for detecting nonpigmented peritoneal endometriotic lesions was 65% compared with 92% (1.42-fold increase). The corresponding specificity was 68% as opposed to 84%. Occult areas of endometriosis were discovered using autofluorescence diagnosis. Statistical analysis was performed with χ² test and McNemar test. Conclusion: Combination of white light illumination and autofluorescence is significantly superior to white light ilumination alone in detecting nonpigmented endometriotic lesions. Autofluorescence diagnosis of nonpigmented endometriotic lesions may become an alternative to fluorescence diagnosis after application of 5-aminolevulinic acid, especially because of no side effects. [ABSTRACT FROM AUTHOR]

Background: Detection of normal and pathologic parathyroid glands often is difficult because of their variability in number and location. The feasibility and efficacy of a fluorescence technique for identifying parathyroids have already been proved in an experimental setting. This is the first report of human fluorescence-guided parathyroidectomy.Methods: A 72-year-old man with primary hyperparathyroidism underwent minimally invasive videoscopically assisted parathyroidectomy after photosensitization with aminolevulinic acid. Under special fluorescence illumination by the D-light, a unilateral directed neck exploration was performed.Results: The enlarged adenoma and an atrophic parathyroid gland could be identified rapidly and removed because of their intense red fluorescence. Surrounding structures such as thyroid, muscles, and soft tissue remained nonfluorescent and could easily be distinguished from the parathyroid glands.Conclusions: The aminolevulinic acid-induced fluorescence technique represents a convincing visual detection method for intraoperative identification of parathyroid glands. The technique serves as an additional tool requiring only moderate technical and clinical expenditure for help in guiding dissection down to a preoperatively localized adenoma. When used together with preoperative ultrasonography and sestamibi scan, the fluorescence technique may justify a unilateral, minimally invasive approach for selected patients. [ABSTRACT FROM AUTHOR]

Background Psoriasis has been shown to highly accumulate protoporphyrin IX (PpIX), but a variable distribution within plaques after fluorescence diagnosis is seen. It is unknown what causes this heterogeneity of fluorescence in psoriatic skin, despite adequate keratolytic treatment. Variations in fluorescence might explain the variable and the mostly partial clinical response of psoriasis seen after photodynamic therapy (PDT). Objectives This study examines morphological and immunohistochemical differences in inhomogeneous PpIX-induced fluorescence in stable plaque psoriasis. Materials and methods Fourteen patients with stable plaque psoriasis were included in this study. In each patient one psoriatic plaque was incubated with 20% 5-aminolaevulinic acid (ALA) ointment for 3 h after keratolytic treatment. Fluorescence diagnosis with ALA-induced porphyrins (FDAP) was performed and subsequently high- and low-fluorescent psoriatic skin samples were biopsied. Biopsies were investigated with respect to histological hyperkeratosis (thickness of stratum corneum), proliferation (Ki-67 antigen), keratinization (K10, filaggrin) and inflammation (CD3). Digital images acquired with FDAP were analysed using image analysis software. Results Inhomogeneous fluorescence was seen in 12 of the 14 plaques. A significantly thicker stratum corneum was found in low-fluorescent psoriatic skin compared with highly fluorescent skin. Fluorescence intensity and thickness of the stratum corneum proved to be negatively correlated. The variable-fluorescent parts of the lesional psoriatic skin showed no differences in epidermal proliferation, keratinization or inflammation. Conclusions Heterogeneous ALA-induced fluorescence in psoriasis plaques related to inhomogeneous distribution of PpIX in the epidermis may result from differences in penetration of ALA and/or light within a plaque caused by differences in stratum corneum thickness. The variable clinical response seen after PDT in psoriasis could be explained by this. These findings are consistent with the general assumption that optimal desquamation prior to FDAP or PDT is required for the most favourable results. [ABSTRACT FROM AUTHOR]

Background Topical 5-aminolaevulinic acid (ALA)-photodynamic therapy (PDT) for the treatment of psoriasis has been evaluated in a few studies. In these studies different treatment parameters were used, there was a variable clinical response, and a nonhomogeneous fluorescence was seen after irradiation with Wood's light. Objectives To study the clinical effectiveness, immunohistochemical changes and protoporphyrin IX accumulation in ALA-PDT in patients with psoriasis. Methods Eight patients with stable plaque psoriasis with symmetrical involvement were included in the study. Two symmetrical plaques were randomly allocated to PDT either with 10% ALA or with placebo. Irradiation consisted of 2 and 8 J cm−2 with a dark interval of 2 h (Waldmann PDT 1200 L, 600–750 nm, 40 mW cm−2) once weekly for 4 weeks. Before, during and after irradiation, fluorescence diagnosis was performed. Biopsies were taken at baseline, week 1 and week 6 for immunohistochemical assessment. Psoriatic plaques were clinically assessed using the plaque severity (sum) score. Fluorescence diagnosis was performed and expression of immunohistochemical markers for proliferation, differentiation and T-cell infiltration [Ki67, keratin 10 (K10), CD4, CD8 and CD45RO] was assessed. Results From week 1 up to week 6, ALA-PDT gave a significant reduction in the number of Ki67+ nuclei, while the K10 expression increased. After 6 weeks significant improvement was observed for CD8 and CD45RO. These changes were absent in the placebo-treated lesions. The sum scores were also significantly lower in the ALA-treated plaques. Heterogeneity of macroscopic fluorescence was observed during treatment despite keratolytic treatment. Conclusions The present study shows that clinical improvement during fractionated ALA-PDT in psoriasis parallels histological improvement as seen in normalization of epidermal proliferation, differentiation and infiltration of relevant T-cell subsets. Optimizing the current treatment protocol may increase clinical efficacy further. [ABSTRACT FROM AUTHOR]