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Lung cancer is the second most common cancer and the leading cause of cancer-related death worldwide. Molecular imaging using [18F]fluorodeoxyglucose Positron Emission Tomography and/or Computed Tomography ([18F]FDG-PET/CT) plays an essential role in the diagnosis, evaluation of response to treatment, and prediction of outcomes. The images are evaluated using qualitative and conventional quantitative indices. However, there is far more information embedded in the images, which can be extracted by sophisticated algorithms. Recently, the concept of uncovering and analyzing the invisible data extracted from medical images, called radiomics, is gaining more attention. Currently, [18F]FDG-PET/CT radiomics is growingly evaluated in lung cancer to discover if it enhances the diagnostic performance or implication of [18F]FDG-PET/CT in the management of lung cancer. In this review, we provide a short overview of the technical aspects, as they are discussed in different articles of this special issue. We mainly focus on the diagnostic performance of the [18F]FDG-PET/CT‐based radiomics and the role of artificial intelligence in non-small cell lung cancer, impacting the early detection, staging, prediction of tumor subtypes, biomarkers, and patient's outcomes.

Background Determining the efficacy, safety, and prognostic factors affecting overall survival (OS) among metastatic prostate cancer patients undergoing PSMA-targeted radioligand therapy (PRLT). Method In this retrospective study, from November 2016 and December 2019, 43 heavily pretreated (90.7% on 1st line androgen deprivation therapy (ADT), 53.5% on 2nd line ADT, 58.1% on docetaxel) metastatic prostate cancer patients with median age of 71 years (range: 51−88 years) were enrolled. Treatment cycles were repeated every 8 weeks (range: 6–12 weeks). To evaluate the biochemical response after each cycle, prostate specific antigen (PSA) levels were measured and analyzed according to the Prostate Cancer Working Group 3 (PCWG3) criteria cutoffs. Possible adverse events after therapy were retrospectively classified according to the Common Toxicity Criteria for Adverse Events (CTCAE) v.5.0. Kaplan-Meier and multivariable Cox proportional hazard regression analyses were used to identify factors associated with OS. Results A total of 112 cycles of PRLT with a median of 3 cycles (range: 1–6) and median administered activity per cycle of 6.29 GBq (range: 4.45–7.7 GBq) were used. PSA decline was observed in 65.1% of patients, and best PSA decline of ≥50% and ≥90% were achieved in 39.5% and 23.3% of patients, respectively. Major (grade III) anemia and thrombocytopenia occurred in 11.6% and 7% of patients, respectively. Median OS and median PSA progression-free survival were 52 and 20 weeks, respectively. In univariate analysis, baseline hemoglobin 2, baseline PSA ≥ 115 ng/mL, cumulative dose of 177Lu-PSMA Conclusion PRLT with 177Lu-PSMA is well-tolerated and effective in metastatic prostate cancer patients who have no other treatment options available. The novel prognostic markers found in this study (high platelet count, superscan pattern) were associated with poor overall survival.

Background. Cancer-associated fibroblasts (CAFs) can strongly modulate the response to therapy of malignant tumor cells, facilitating their continuous proliferation and invading behaviors. In this context, several efforts were made in identifying the fibroblast activation protein (FAP) as a CAF recognizer and in designing FAP-specific PET radiotracers (as 68Ga-FAPI) along with FAP-specific therapeutic radioligands. Herein, we review different clinical studies using the various FAP-specific radioligands as novel theranostic agents in a wide range of oncologic and nononcologic indications. Methods. A comprehensive systematic search was conducted on the PubMed and Scopus databases to find relevant published articles concerning the FAP-specific PET imaging as well as the FAP-specific radionuclide therapy in patients with oncologic and nononcologic indications. The enrolled studies were dichotomized into oncologic and nononcologic categories, and the required data were extracted by precisely reviewing the whole text of each eligible study. A meta-analysis was also performed comparing the detection rates of 68Ga-FAPI vs. 18F-FDG PET/CT using odds ratio (OR) and risk difference as outcome measures. Results. Of the initial 364 relevant papers, 49 eligible articles (1479 patients) and 55 case reports were enrolled in our systematic review. These studies observed high radiolabeled FAPI avidity as early as 10 minutes after administration in primary sites of various malignant tumors. Based on the meta-analysis which was done on the reported detection rates of the 68Ga-FAPI and 18F-FDG PET/CT scans, the highest OR belonged to the primary lesion detection rate of gastrointestinal tumors (OR = 32.079, 95% CI: 4.001–257.212; p = 0.001) with low heterogeneity (I2 = 0%). The corresponding value of the nodal metastases belonged to hepatobiliary tumors (OR = 11.609, 95% CI: 1.888–71.365; p = 0.008) with low heterogeneity (I2 = 0%). For distant metastases, the highest estimated OR belonged to nasopharyngeal carcinomas (OR = 77.451, 95% CI: 7.323–819.201; p < 0.001 ) with low heterogeneity (I2 = 0%). Conclusions. The outperformance of 68Ga-FAPI PET/CT over 18F-FDG PET/CT in identifying certain primary tumors as well as in detecting their metastatic lesions may open indications for evaluation of cases with inconclusive 18F-FDG PET/CT findings. What needs to be emphasized is that the false-positive results might be problematic and must be taken into account in 68Ga-FAPI PET/CT interpretation. More clarification on the role of FAPI radioligands in oncologic imaging, radionuclide therapy, and radiotherapy treatment planning is therefore required.

A 61-year-old woman with a history of metastatic follicular thyroid carcinoma became radioiodine-refractory following two doses of radioiodine (RAI) therapy (cumulative = 230 mCi). While no RAI-avid lesion was noticed in the last post-ablation whole-body radioiodine scan (WBIS), she reported sternal pain, which was accompanied by rapidly rising thyroglobulin levels. 18F-FDG and 68Ga-DOTA-TATE PET/CT was performed, showing metastatic pulmonary nodules and a lytic sternal lesion with acceptable avidity (i.e. uptake ≥ liver). Following four cycles of peptide receptor radionuclide therapy (PRRT) with 177Lu-DOTA-TATE, the thyroglobulin levels dropped significantly, and the sternal pain was partially alleviated. Despite only experiencing grade I thrombocytopenia, the treating physician decided to discontinue PRRT and repeat the diagnostic WBIS. Surprisingly, the scan revealed significantly increased tracer uptake in the sternum. The patient received 200 mCi 131I, and WBIS showed increased RAI uptake in all pulmonary nodules as well as bone metastases. We report a case of RAI-refractory thyroid carcinoma with a somatostatin-receptor expression that re-differentiated and gained significant RAI uptake capacity after PRRT.

A 2-month-old infant was referred for hepatobiliary scintigraphy due to ascites of unknown cause. The top differential diagnosis was spontaneous perforation of the biliary ducts. Delayed images up to 4 hours were against this diagnosis showing normal distribution of the radiotracer throughout the bowel. However, on delayed images, the scan showed mild tracer retention in the ascites confirmed by SPECT/CT images. Surprisingly, the exploratory abdominal surgery revealed an intact hepatobiliary system, pointing toward other possible etiologies. Second-review surgery was performed due to uncontrolled progressive ascites showing congestive hepatopathy and biliary leak from the hepatic surface suggestive of the "crying liver".

Medical university students are more likely to use non-prescribed stimulants, due to the claim that some of these drugs may improve learning abilities and concentration. Side effects of non-prescri...

Purpose: Painful metastatic bone involvement is common in advanced stages of many cancers. Between available radionuclides for bone pain palliation, no consensus has been reached on lutetium ethyle...

A patient with multiple endocrine neoplasia type 2A syndrome who had exhausted several surgeries and radiotherapy was referred to nuclear medicine department for theranostic approaches. [68Ga]-DOTATATE PET/CT and [131I]I-mIBG SPECT/CT were performed, but the degree of uptake was insufficient for using the treatment companion of these tracers. Finally, 1 year later, [68Ga]-FAPI-46 PET/CT showed progressive disease with metastases to the lung, liver, bone, and lymph nodes with intense [68Ga]-FAPI-46 uptake. Treatment with [177Lu]Lu-FAPI-46 was done, and the patient tolerated treatment and showed evidence of clinical improvement following therapy.

A 65 years old man with high-risk prostate adenocarcinoma underwent bone scintigraphy with 99mTc-methylene diphosphate (99mTc-MDP). The scan revealed a focus of radiotracer uptake in the left pubic region, which was suspicious for metastatic involvement. Additional imaging with single photon emission computed tomography (SPECT/CT) confined the uptake to be extra-osseous and contributed to the calcified zone in the prostate bed. Prostatic bed calcification with 99mTc-MDP uptake mimics metastasis and can be easily missed on planar images.

Background Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are among the most severe dermatologic reactions to the drugs. Data about SJS and TEN among pediatric population especially in Iran is limited. This study aimed to investigate the clinical and para-clinical characteristics of pediatric patients with SJS/TEN. Materials and Methods From 2010 to 2016, all SJS and TEN children from three teaching hospitals in Mashhad-Iran with age less than 15 years were included in the study. Patients’ catechistic, history, physical examinations, progress notes, laboratory findings, medical consults, treatments taken and the final outcome were extracted from medical records by researcher. Data were further analyzed by SPSS (version 17.0). Results Among 165 records, 48 children (58.3% male; mean age of 9.1 years) were among the SJS and TEN spectrum. Anticonvulsants (50%; including lamotrigine, phenobarbital, phenytoin, carbamazepine, valproate and clobazam) were the most common drugs followed by antibiotics (38.1%; including cefixime, penicillin, azithromycin, co-amoxiclav, cephalexin, co-trimoxazole and ceftriaxone), and analgesics (9.5%; including acetaminophen, ibuprofen and naproxen). Infectious agents were the possible cause of SJS/TEN in two patients. WBC counts, liver function tests, renal and electrolyte tests were significantly different in SJS and TEN groups. Conclusion The main suspected medications found in this study were anticonvulsants and antibiotics and the mortality rate was 12.5%. The main suspected medications found in this study were anticonvulsants and antibiotics and the mortality rate was 12.5%.

Prostate cancer with NED (neuroendocrine differentiation) may occur in various stages of the disease, which is associated with a poor prognosis and treatment resistance. We present a case of a patient with metastatic castration-resistant prostatic cancer, who was treated with 7 cycles of 177Lu-PSMA and a very good response. Although only few foci with PSMA uptake were remained in the last posttreatment images, PSA levels dramatically began to rise. This raised suspicion for NED, and 68Ga-DOTATATE was done showing sufficient uptake to consider a trial of 177Lu-DOTATATE. The patient reported pain response, and PSA levels dropped after 1 cycle of the treatment.

Determining the efficacy, safety, and prognostic factors affecting overall survival (OS) among metastatic prostate cancer patients undergoing PSMA-targeted radioligand therapy (PRLT).In this retrospective study, from November 2016 and December 2019, 43 heavily pretreated (90.7% on 1st line androgen deprivation therapy (ADT), 53.5% on 2nd line ADT, 58.1% on docetaxel) metastatic prostate cancer patients with median age of 71 years (range: 51-88 years) were enrolled. Treatment cycles were repeated every 8 weeks (range: 6-12 weeks). To evaluate the biochemical response after each cycle, prostate specific antigen (PSA) levels were measured and analyzed according to the Prostate Cancer Working Group 3 (PCWG3) criteria cutoffs. Possible adverse events after therapy were retrospectively classified according to the Common Toxicity Criteria for Adverse Events (CTCAE) v.5.0. Kaplan-Meier and multivariable Cox proportional hazard regression analyses were used to identify factors associated with OS.A total of 112 cycles of PRLT with a median of 3 cycles (range: 1-6) and median administered activity per cycle of 6.29 GBq (range: 4.45-7.7 GBq) were used. PSA decline was observed in 65.1% of patients, and best PSA decline of ≥50% and ≥90% were achieved in 39.5% and 23.3% of patients, respectively. Major (grade III) anemia and thrombocytopenia occurred in 11.6% and 7% of patients, respectively. Median OS and median PSA progression-free survival were 52 and 20 weeks, respectively. In univariate analysis, baseline hemoglobin11.2 g/dL, baseline platelets count ≥327,000/μL, PSA decline20.94% after first cycle of therapy, Eastern Cooperative Oncology Group (ECOG)2, baseline PSA ≥ 115 ng/mL, cumulative dose ofPRLT with

We reported 99m-Tc phytate accumulation in the pyelocalyceal system of the kidney in the lymphoscintigraphic images of a 3.5 months-old male infant with chylous ascites, which was mistaken with the site of lymph leakage. SPECT/CT localized activity in the para-aortic region to the renal pelvis and on delayed images, this was disappeared. Our case illustrates the added value of SPECT/CT for the differentiation of possible false-positive findings in lymphoscintigraphy.

A 56-year-old man with metastatic castration-resistant prostate cancer was referred for radioligand therapy with Lu-prostate-specific membrane antigen. In the third cycle, a posttherapy whole-body scan showed unexpected skeletal and joint uptake apart from his known metastatic lesions. This observation raised suspicion for possible impurity (mainly free lutetium) in the applied radiopharmaceutical product. After contacting the radiopharmaceutical company, we were informed that the radiochemical purity of the used batch of Lu-prostate-specific membrane antigen had been 95%. This is the first report of excess free lutetium scan pattern and its complications in a patient undergoing radioligand therapy.

Background Healthcare-associated infections (HAIs) challenge modern medicine. Considering their high prevalence in Iran, we aimed to provide knowledge on the subject, and to teach about the importance of infection prevention and control (IPC) to a broad audience of pre-graduate healthcare professionals, focusing on education as the cornerstone of IPC. Main body We invited Iranian medical students to present ideas on “how to reduce HAIs.” Projects were eligible if being original and addressing the call. Accepted projects were quality assessed using a scoring system. Forty-nine projects were submitted, of which 37 met the inclusion criteria. They had a mean score of 69.4 ± 18.3 out of the maximum possible score of 115. Four reviewers assessed the 37 projects for clinical applicability, impact on patient safety, and innovation, and selected the best 12 to compete at the 2nd International Congress on Prevention Strategies for Healthcare-associated Infections, Mashhad, Iran, 2018. The competition took place in three rounds. The selected teams presented their projects in the first round and debated one by one in a knockout manner, while the jury reviewed their scientific content and presentation skills. In the second round, the top 5 projects competed for reaching the final stage, in which the teams presented their ideas in front of a panel of international IPC experts to determine the first three ranks. At the end of the contest, the participants gained valuable criticisms on how to improve their ideas. Moreover, by its motivating atmosphere, the contest created an excellent opportunity to promote IPC in medical schools. Conclusions Using innovation contests in pre-graduates is an innovative education strategy. It sensitizes medical students to the challenges of IPC and antimicrobial resistance and drives them to think about solutions. By presenting and defending their innovations, they deepen their understanding on the topic and generate knowledge transfer in both ways, from students to teachers and vice versa.

Efflux pumps are well known as a key role to fluoroquinolone resistance in methicillin-resistant Staphylococcus aureus (MRSA). In this study, among 60 clinical MRSA isolates, 42 isolates (70%) were resistant to ciprofloxacin. MRSA were isolated to detect efflux genes including norA, norB, norC, mepA, sepA, mdeA, qacA/B and smr. Isolates subjected to PCR detection and DNA sequence analysis for these genes. PCR detection showed that 42 isolates (70%) contained at least one efflux pump gene. Among ciprofloxacin-resistant isolates, mdeA and qacA/B genes were found with the highest (61.7%) and lowest (3.3%) frequency, respectively. We also observed that the highest minimum inhibitory concentrations of ciprofloxacin in the presence of mdeA+mepA+norA-C+sepA+smr combination. This type of combination may have the greatest impact on resistance to ciprofloxacin. Finally, compared to previous studies, our study demonstrates that prevalence of ciprofloxacin resistance has been increasing among MRSA clinical isolates.

Background: Infections due to Staphylococcus aureus have long been considered as a big challenge to clinicians. The innate ability of this microorganism to develop resistance to different antibiotics, has led to the appearance of MRSA (methicillin-resistant Staphylococcus aureus) and lately VRSA (vancomycin-resistant Staphylococcus aureus) strains, which are considered as major problems for both patients and clinicians. Objectives: In this study, we tried to evaluate susceptibility pattern of S. aureus isolates against some prevalent antibiotics as well as some infrequent ones. Materials and Methods: This inquiry was performed on 238 clinical samples, collected from different wards of Imam Reza Hospital of Mashhad between 2011 and 2012, which were previously defined as S. aureus and stocked in -70°C. Kirby-Bauer’s disc diffusion was performed for the following antibiotics: quinupristin-dalfopristin, linezolid, cefoxitin and mupirocin according to EUCAST 2014 (v. 4), co trimoxazole, doxycycline, tigecycline, oxacillin based on CLSI 2012 (M100-S22) and vancomycin according to CLSI 2007 guidelines. Results: Out of 238 samples, 5.88% were resistant to quinupristin-dalfopristin; 5.46% to linezolid; 60.92% to Co-trimoxazole; 31.93% to doxycycline; 18.90% to tigecycline; 5.04% to vancomycin; 9.24% to mupirocin; 43% to oxacillin and 46.21% of our isolates were resistant to cefoxitin. Conclusions: Coming across isolates with reduced susceptibility to quinupristin-dalfopristin and resistant to linezolid in this study are worrisome although these antibiotics are not used in our hospital. This might be a new challenge in the treatment of MRSA.

At the 10th anniversary of the first report of vanA vancomycin-resistant Staphylococcus aureus (VRSA), we aimed to determine the total number of vanA-VRSA reported in the literature. Relevant key words were used to search through PubMed, Sciverse, and Google Scholar, as well as the abstract

Background: Staphylococcus aureus is a major human pathogen worldwide. Vancomycin has been used for decades to treat multidrug resistant S. aureus. Ten years has passed since the first report of van­comycin resistant S. aureus (VRSA). The objective of this systematic review was to determine the total number of VRSA isolates that have been reported from Iran. Methods: Search terms reflected “Iran”, “vancomycin” and “S. aureus” were searched in the ISI web of knowledge, PubMed, SciVerse, and Google scholar. Also two Persian scientific databases and 13 recent national congresses were investigated. Articles / abstracts working on S. aureus in Iran, evaluating vancomycin MIC and/or PCR of vanA/B were included in this systematic review. Results: Out of the 3484 records found in mentioned resources, 13 re­lated studies were included in the final analysis. The result showed that at least 24 VRSA isolates which have been reported from Iran up to September 2012. Conclusion: It seems that many Iranian researchers did not follow a specific guideline for reporting and confirming VRSA. Establishing an Iranian reference center where studies on VRSA can be registered, evaluated and confirmed is strongly recommended.

Objective(s) Staphylococcus aureus (S. aureus) is a prevalent pathogen worldwide. Methicillin resistant S. aureus (MRSA), which is usually multi-resistant in hospitals, has been a daunting challenge for clinicians for more than half a century. The aim of this systematic review and meta-analysis is to determine the relative frequency (R.F.) of MRSA in different regions of Iran. Materials and Methods Search terms “Staphylococcus aureus”, “Methicillin”, “mecA” and “Iran” were used in PubMed, Scirus and Google Scholar. Two Persian scientific search engines and ten recent national congresses were also explored. Articles/abstracts, which used clinical specimens and had done PCR to detect the mecA gene, were included in this review. Comprehensive Meta-Analysis and Meta-Analyst software were used for statistical analysis. Results Out of 2690 results found in the mentioned databases, 48 articles were included in the final analysis. These studies were done in Ahvaz, Falavarjan, Fasa, Gorgan, Hamedan, Isfehan, Kashan, Mashhad, Sanandaj, Shahrekord, Shiraz, Tabriz, Tehran and Tonekabon. Pooled estimation of 7464 S. aureus samples showed that 52.7%±4.7 (95% confidence interval [CI]) of strains were mecA positive. MRSA R.F. in different studies varied from 20.48% to 90% in Isfehan and Tehran, respectively. We found a moderate heterogeneity (I2= 48.5%) of MRSA R.F. among studies conducted in Tehran (ranging from 28.88% to 90%, mean 52.7% [95% CI: 46.6%±0.58.8%]). Conclusion According to the results of this study, MRSA R.F. in Iran is in the high range. Thus, measures should be taken to keep the emergence and transmission of these strains to a minimum.