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Implantation is a modern method of administering chemotherapeutic agents, with a highly targeted effect and better patient tolerance due to the low frequency of administration. Implants are capable of controlled release, which makes them a viable alternative to infusional chemotherapy, allowing patients to enjoy a better quality of life without the need for prolonged hospitalization. Compared to subcutaneous implantation, intratumoral implantation has a number of significant advantages in terms of targeting and side effects, but this area of chemotherapy is still poorly understood in terms of clinical trials. At the same time, there are more known developments of drugs in the form of implants and injections for intratumoral administration. The disadvantages of classical intratumoral implants are the need for surgical intervention to install the system and the increased risk of tumor rupture noted by some specialists. The new generation of implants are in situ implants—systems formed in the tumor due to a phase transition (sol–gel transition) under the influence of various stimuli. Among this systems some are highly selective for a certain type of malignant neoplasm. Such systems are injected and have all the advantages of intratumoral injections, but due to the phase transition occurring in situ, they form depot forms that allow the long-term release of chemotherapeutic agents. [ABSTRACT FROM AUTHOR]

Implantation is a modern method of administering chemotherapeutic agents, with a highly targeted effect and better patient tolerance due to the low frequency of administration. Implants are capable of controlled release, which makes them a viable alternative to infusional chemotherapy, allowing patients to enjoy a better quality of life without the need for prolonged hospitalization. Compared to subcutaneous implantation, intratumoral implantation has a number of significant advantages in terms of targeting and side effects, but this area of chemotherapy is still poorly understood in terms of clinical trials. At the same time, there are more known developments of drugs in the form of implants and injections for intratumoral administration. The disadvantages of classical intratumoral implants are the need for surgical intervention to install the system and the increased risk of tumor rupture noted by some specialists. The new generation of implants are in situ implants—systems formed in the tumor due to a phase transition (sol–gel transition) under the influence of various stimuli. Among this systems some are highly selective for a certain type of malignant neoplasm. Such systems are injected and have all the advantages of intratumoral injections, but due to the phase transition occurring in situ, they form depot forms that allow the long-term release of chemotherapeutic agents.

Abstract: The acidosis of tumor microenvironments is one of the universal phenomena of solid tumors, and the increased acidity may be in fact essential intermediates in the progression of tumor growth and several lethal phenotypic traits of tumors, such as invasion and metastasis. Acid-labile polymers PBELA with incorporating acetal groups into biodegradable backbone of poly(d,l-lactide)–poly(ethylene glycol) (PELA) were utilized to load hydroxycamptothecin (HCPT) into electrospun fibers for intratumoral chemotherapy. Compared with that under a simulated physiological condition of pH 7.4, the incubation of PBELA fibers in acidic media resulted in larger mass loss and molecular weight reduction of fiber matrices and enhanced HCPT release from fibers. In vitro cytotoxicity assay of HCPT-loaded PBELA fibers indicated 6-fold higher inhibitory activity against HepG2 cells after incubation in pH 6.8 media than that of pH 7.4, while there was no significant difference for free HCPT and HCPT-loaded PELA fibers. The tumor growth, tumor cell apoptosis, and animal survival rate after intratumoral implantation of HCPT-loaded PBELA fibers indicated a superior in vivo antitumor activity and fewer side effects than other treatment. Therefore, acid-labile electrospun fibers may be promising implants for localized therapy of inoperable tumors and for prevention of post-surgical tumor recurrence. [Copyright &y& Elsevier]

Abstract: Emulsion electrospinning was used in the present study to prepare core–sheath structured fibers with core-loading of hydroxycamptothecin (HCPT), and their antitumor activities were evaluated both in vitro on cancer cell lines and in vivo on tumor bearing mice via intratumoral implantation. Compared with our previous investigation on blend electrospun fibers, the addition of 2-hydroxypropyl-β-cyclodextrin (HPCD) and the preferential formation of HPCT/HPCD inclusion complexes resulted in significantly faster HCPT release from and higher degradation rate of emulsion electrospun fibers. The core–sheath structure led to around 93% of lactone form remaining after emulsion electrospinning and incubation in buffer solutions for over one month. In vitro cytotoxicity tests on HCPT-loaded electrospun fibers indicated over 20 times higher inhibitory activity against HepG2 cells than free HCPT during 72h incubation. Hepatoma H22 cells were subcutaneously injected into Kunming mice to form solid tumors for in vivo tests on the antitumor efficacy. Based on the tumor volume, survival rate and body weight changes, HCPT-loaded fibers indicated superior in vivo antitumor activities to and fewer side effects than free HCPT. The histopathological staining and immunohistochemical examinations of caspase-3 expression indicated more necrosis and apoptosis induced by HCPT-loaded fibers. The above results demonstrate the potential use of emulsion electrospun fibers as drug carriers for local treatment of solid tumors. [Copyright &y& Elsevier]

The close proximity of the endoscopic ultrasound (EUS) probe to the pancreas, coupled with the ease with which a needle can be inserted into a pancreatic lesion, have contributed to the development of EUS-guided therapies for both adenocarcinoma and neuroendocrine pancreatic neoplasms. EUS-guided fine needle injection of different types of drugs, implantation of fiducial markers to facilitate stereotactic body radiation therapy or of radioactive seeds to perform brachytherapy, and the use of different thermal and nonthermal ablation devices and techniques have all been tested in preliminary human studies. This manuscript will present the available evidence accumulated thus far in the field of EUS-guided oncological treatment of pancreatic solid tumors, along with a look into possible future applications., (Copyright © 2021 Elsevier Inc. All rights reserved.)