BACKGROUND: Acral actinic keratosis (AK) lesions are considered difficult to treat, and published data for photodynamic therapy (PDT) on these lesions is limited. Thus, we evaluated sustained efficacy, safety, and satisfaction after PDT for AK on the hands.
METHODS: We analysed subgroup data for treatment on the hands from a randomised, double-blind, intra-individual phase III study. All participants previously underwent up to two field-directed red light PDTs with 10% 5-aminolevulinic acid nanoemulsion gel (BF-200 ALA). Assessments included pain during PDT, clearance and recurrence rates, and satisfaction.
RESULTS: 24 participants treated on the hands were included; 21 participants were analysed. Complete clearance rates with BF-200 ALA were 90.9% (lesion-based) and 76.2% (per participant\'s side), both markedly higher than with vehicle. The lesion recurrence rate with BF-200 ALA was 29.0%. Adverse events reflected the mode of action. Mean pain intensities were 4.8 ± 3.8 (BF-200 ALA) and 0.8 ± 2.1 (vehicle) on an 11-point numeric rating scale. Most participants (81.0%) rated their satisfaction with BF-200 ALA as very good or good.
CONCLUSIONS: This subgroup analysis indicates that PDT with BF-200 ALA provides a suitable treatment for AK lesions on the hands.

Dermatosis papulosa nigra (DPN) is a type of benign epidermal hyperplasia that affects the appearance of patients and poses a threat to their physical and mental health. Photodynamic therapy (PDT) has been shown to have the advantages of non-invasiveness, efficacy, and low recurrence in the treatment of skin disorders. However, no studies have been reported on the use of PDT for the treatment of DPN. Therefore, we used PDT for the first time to treat DPN and monitor its efficacy. Forty-five patients with DPN diagnosed at the outpatient clinic of Changzhou First People\'s Hospital were treated with 10% 5-aminolevulinic acid (ALA) once a week for four consecutive weeks and followed for 3 months. After four treatment sessions, the cure rate among the 45 patients was 71.1%, and the overall efficacy rate was 93.3%. The most common adverse reactions were mild erythema, edema, and temporary pigmentation. PDT is expected to become a new and effective treatment for DPN.

Photodynamic therapy (PDT) is a minimally invasive treatment showing promise against cancer and microbial infections. PDT targets tumor cells while sparing healthy tissue, reducing side effects. It induces immunogenic cell death, potentially stimulating antitumor immune responses and reducing cancer recurrence. In microbial treatment, PDT effectively combats bacteria, fungi and viruses. Combining PDT with chemotherapy, radiotherapy and immunotherapy enhances its efficacy. However, challenges such as tumor hypoxia, limited tissue penetration and phototoxicity necessitate ongoing research efforts to optimize PDT protocols and overcome limitations. Overall, PDT is versatile and continually advancing with refined protocols to improve its clinical utility against cancer and microbial infections.

Significance: Despite the widespread use of photodynamic therapy in clinical practice, there is a lack of personalized methods for assessing the sufficiency of photodynamic exposure on tumors, depending on tissue parameters that change during light irradiation. This can lead to different treatment results. Aim: The objective of this article was to conduct a comprehensive review of devices and methods employed for the implicit dosimetric monitoring of personalized photodynamic therapy for tumors. Methods: The review included 88 peer-reviewed research articles published between January 2010 and April 2024 that employed implicit monitoring methods, such as fluorescence imaging and diffuse reflectance spectroscopy. Additionally, it encompassed computer modeling methods that are most often and successfully used in preclinical and clinical practice to predict treatment outcomes. The Internet search engine Google Scholar and the Scopus database were used to search the literature for relevant articles. Results: The review analyzed and compared the results of 88 peer-reviewed research articles presenting various methods of implicit dosimetry during photodynamic therapy. The most prominent wavelengths for PDT are in the visible and near-infrared spectral range such as 405, 630, 660, and 690 nm. Conclusions: The problem of developing an accurate, reliable, and easily implemented dosimetry method for photodynamic therapy remains a current problem, since determining the effective light dose for a specific tumor is a decisive factor in achieving a positive treatment outcome.

Bladder cancer (BC) possesses distinct molecular profiles that influence progression depending on its biological nature and delivered treatment intensity. Muscle-invasive BC (MIBC) and non-MIBC (NMIBC) demonstrate great intrinsic heterogeneity regarding different prognoses, survival, progression, and treatment outcomes. Transurethral resection of bladder tumor (TURBT) is the standard of care in treating NMIBC and serves both diagnostic and therapeutic purposes despite the prevalent recurrence and progression among many patients. In particular, flat urothelial carcinoma in situ and urothelial carcinoma with lamina propria invasion are the major precursors of MIBC. A new-generation photosensitizer, 5-Aminolevulinic acid (5-ALA), demonstrates high tumor specificity by illuminating the tumor lesion with a specific wavelength of light to produce fluorescence and has been studied for photodynamic diagnosis to detect precise tumor areas by TURBT. Additionally, it has been applied for treatment by producing its cytotoxic reactive oxygen species, as well as screening for urological carcinomas by excreting porphyrin in the blood and urine. Moreover, 5-ALA may contribute to screening before and after TURBT in NMIBC. Here, we summarize the updated evidence and ongoing research on photodynamic technology for NMIBC, providing insight into the potential for improving patient outcomes.

Cancer development is related to genetic mutations in primary cells, where 5-10% of all cancers are derived from acquired genetic defects, most of which are a consequence of the environment and lifestyle. As it turns out, over half of cancer deaths are due to the generation of drug resistance. The local delivery of chemotherapeutic drugs may reduce their toxicity by increasing their therapeutic dose at targeted sites and by decreasing the plasma levels of circulating drugs. Nanobubbles have attracted much attention as an effective drug distribution system due to their non-invasiveness and targetability. This review aims to present the characteristics of nanobubble systems and their efficacy within the biomedical field with special emphasis on cancer treatment. In vivo and in vitro studies on cancer confirm nanobubbles\' ability and good blood capillary perfusion; however, there is a need to define their safety and side effects in clinical trials.

Chemotherapy is among the main classical approaches to the treatment of oncologic diseases. Its efficiency has been comprehensively proven by clinical examinations; however, the low selectivity of chemotherapeutic agents limits the possibilities of this method, making it necessary to search for new approaches to the therapy of oncologic diseases. Photodynamic therapy is the least invasive method and a very efficient alternative for the treatment of malignant tumors; however, its efficiency depends on the depth of light penetration into the tissue and on the degree of oxygenation of the treatment zone. In this work, a hitherto unknown conjugate of a natural bacteriochlorin derivative and doxorubicin was obtained. In vitro and in vivo studies showed a more pronounced activity of the conjugate against MCF-7 and 4T1 cells and its higher tumorotropicity in animal tumor-bearing animals compared to free anthracycline antibiotic. The suggested conjugate implements the advantages of photodynamic therapy and chemotherapy and has great potential in cancer treatment.

Chlorin e6 is a well-known photosensitizer used in photodynamic diagnosis and therapy. A method for identifying and purifying a novel process-related impurity during the synthesis of chlorin e6 has been developed. Its structure was elucidated using NMR and HRMS. This new impurity is formed from chlorophyll b rather than chlorophyll a, which is the source of chlorin e6. The intermediates formed during chlorin e6 synthesis were monitored using HPLC-mass spectrometry. This new impurity was identified as rhodin g7 71-ethyl ester, the structure of which remains unknown to date. The cytotoxic effects of this novel compound in both dark and light conditions were studied against five cancer cell lines (HT29, MIA-PaCa-2, PANC-1, AsPC-1, and B16F10) and a normal cell line (RAW264.7) and compared to those of chlorin e6. Upon irradiation using a laser at 0.5 J/cm2, rhodin g7 71-ethyl ester demonstrated higher cytotoxicity (2-fold) compared to chlorin e6 in the majority of the cancer cell lines. Furthermore, this new compound exhibited higher dark cytotoxicity compared to chlorin e6. Studies on singlet oxygen generation, the accumulation in highly vascular liver tissue, and the production of reactive oxygen species in MIA-PaCa-2 cancer cells via rhodin g7 71-ethyl ester correspond to its higher cytotoxicity as a newly developed photosensitizer. Therefore, rhodin g7 71-ethyl ester could be employed as an alternative or complementary agent to chlorin e6 in the photodynamic therapy for treating cancer cells.

Prostate cancer is the most prevalent cancer among men in the United States and is a leading cause of cancer-related death. Prostate specific membrane antigen (PSMA) has been established as a biomarker for prostate cancer diagnosis and treatment. This study aimed to develop a novel theranostic agent, PSMA-1-MMAE-Pc413, which integrates a PSMA-targeting ligand, the photosensitizer Pc413, and the microtubular inhibitor monomethyl auristatin E (MMAE) for synergistic therapeutic efficacy. In vitro uptake studies revealed that PSMA-1-MMAE-Pc413 demonstrated selective and specific uptake in PSMA-positive PC3pip cells but not in PSMA-negative PC3flu cells, with the uptake in PC3pip cells being approximately three times higher. In vitro cytotoxicity assays showed that, when exposed to light, PSMA-1-MMAE-Pc413 had a synergistic effect, leading to significantly greater cytotoxicity in PSMA-positive cells (IC50 = 2.2 nM) compared to PSMA-1-Pc413 with light irradiation (IC50 = 164.9 nM) or PSMA-1-MMAE-Pc413 without light irradiation (IC50 = 12.6 nM). In vivo imaging studies further demonstrated the selective uptake of PSMA-1-MMAE-Pc413 in PC3pip tumors. In in vivo studies, PSMA-1-MMAE-Pc413 dramatically improves the therapeutic outcome for prostate cancer by providing a synergistic effect that surpasses the efficacy of each treatment modality alone in PC3pip tumors. These findings suggest that PSMA-1-MMAE-Pc413 has strong potential for clinical application in improving prostate cancer treatment.

OBJECTIVE: To evaluate the changes in choroidal thickness 1 year after half-dose photodynamic therapy (PDT) for central serous chorioretinopathy (CSC) using widefield swept-source optical coherence tomography.
METHODS: We retrospectively reviewed 21 patients with CSC who unilaterally underwent half-dose PDT and completed a 12-month follow-up. Choroidal thickness was evaluated before and after PDT within an 18-mm circular grid centered on the fovea subdivided into nine areas in the treated and untreated fellow eyes.
RESULTS: All 21 treated eyes showed complete resolution of subretinal fluid at 3 months after PDT, without any recurrence at 12 months. The mean choroidal thickness in all nine areas significantly decreased after PDT at 3 months (P < 0.05) and remained unchanged at 12 months (P < 0.05) compared with that at baseline. However, the subtracted choroidal thickness maps between 3 and 12 months detected significant variations among the cases, classified into an enhanced pattern in 10 eyes (47.6%), an attenuated pattern in six eyes (28.6%), and a stable pattern in five eyes (23.8%). The 21 untreated fellow eyes also showed a decrease in mean choroidal thickness in three of the nine subdivided areas at 12 months (P < 0.05), but this decrease was limited posteriorly.
CONCLUSIONS: The reduction in mean choroidal thickness after half-dose PDT for CSC was extensively maintained for 1 year. However, subclinical hemodynamic changes in the entire choroid occurred longitudinally even in the absence of disease recurrence.