Phototheranostics of Cervical Neoplasms with Chlorin e6 Photosensitizer

(1) Purpose: Improving the treatment effectiveness of intraepithelial neoplasia of the cervix associated with human papillomavirus infection, based on the application of the method of photodynamic therapy with simultaneous laser excitation of fluorescence to clarify the boundaries of cervical neoplasms. (2) Methods: Examination and treatment of 52 patients aged 22 to 53 years with morphologically and cytologically confirmed mild to severe intraepithelial cervix neoplasia, preinvasive, micro-invasive, and squamous cell cervix carcinoma. All patients were carriers of human papillomavirus infection. The patients underwent photodynamic therapy with simultaneous laser excitation of fluorescence. The combined use of video and spectral fluorescence diagnostics for cervical neoplasms made it possible to control the photodynamic therapy process at all stages of the procedure. Evaluation of the photodynamic therapy of intraepithelial cervical neoplasms was carried out with colposcopic examination, cytological conclusion, and morphological verification of the biopsy material after the photodynamic therapy course. The success of human papillomavirus therapy was assessed based on the results of the polymerase chain reaction. (3) Results. The possibility of simultaneous spectral fluorescence diagnostics and photodynamic therapy using a laser source with a wavelength of 660 nm has been established, making it possible to assess the fluorescence index in real-time and control the photobleaching of photosensitizers in the irradiated area. The treatment of all 52 patients was successful after the first photodynamic therapy procedure. According to the PCR test of the discharge from the cervical canal, the previously identified HPV types were not observed in 48 patients. Previously identified HPV types were absent after repeated PDT in four patients (CIN III (n = 2), CIS (n = 2)). In 80.8% of patients, regression of the lesion was noted. (4) Conclusions. The high efficiency of photodynamic therapy with intravenous photosensitizer administration of chlorin e6 has been demonstrated both in relation to eradication therapy of human papillomavirus and in relation to the treatment of intraepithelial lesions of the cervix.

Development of a video fluorescence registration system for a LED emitter

Photodynamic therapy (PDT) is widely implemented in clinical practice. This contributes to the development of new devices for conducting fluorescence diagnostics (FD) and PDT. One of the key parameters for the new devices is the ability to perform PDT and evaluate the fluorescence signal during PDT. Most PDT devices do not have the ability to perform PD and register a fluorescent signal, which is important for monitoring the quality of treatment. The purpose of this work is to develop a new device that will be able to conduct PD and PDT during the operation. Using a video system with software for it and an LED irradiator with several types of LEDs. The results show the effective use of this system and the ability to observe FD, as well as conduct.

Investigation of the phenomenon of photobleaching and evaluation of the effectiveness of treatment using a led photodynamic therapy device on optical phantoms

The mortality rate from various oncological diseases remains consistently extremely high, even in spite of recent breakthrough discoveries in the field of cancer therapy [1-3]. One of the most promising cancer treatments is photodynamic therapy (PDT) combined with fluorescence diagnostics (FD) [4, 5]. This study aims to evaluate the efficiency of the PDT procedure using an experimental LED device for photodynamic therapy and fluorescence diagnostics of neoplasms by the level of photobleaching of the photosensitizer protoporphyrin IX (PPIX) in optical phantoms of the skin. The results of spectral measurements showed that the LEDs is able to effectively induce oxidative stress in cancer cells, and due to the presence of a video system, it becomes possible to register the level of tissue fluorescence.

Fluorescence diagnostics and photodynamic therapy of squamous cell carcinoma of the lateral surface of the tongue using the photosensitizer chlorin e6 by spectroscopic video fluorescence methods

This paper presents the results of using intraoperative fluorescence diagnostics (FD) with the endoscopic video system to increase the efficiency of photodynamic therapy (PDT). The molecular form of chlorin e6 was used as a photosensitizer (PS). All patients received an intravenous administration drug based on chlorin e6 at the concentration of 1 mg/kg. Diagnostics and therapy were carried out in 4 patients diagnosed by malignant neoplasms of the lateral surface of the tongue. Determination of the boundaries by changing the signal of the fluorescence intensity of the tumor was carried out before PDT and after PDT. The efficiency of PDT was assessed by the fluorescent signal of the tumor decreasing when compared with non-pathological normal tissue. The FD method allows to determine accurately the actual size of the tumor and its borders. All patients underwent PDT influenced by the therapeutic laser with a generation wavelength of 660 nm. It is shown that the using of fluorescence diagnostics improves the quality of the photodynamic therapy, since it is possible to assess the photobleaching of the drug during the operation.

Novel chlorophyll a derivatives with ester-linked galactose fragments for photodynamic therapy and fluorescence diagnostics of cancer

In the present work, a number of chlorophyll [Formula: see text] derivatives were synthetized with galactose fragments with an ester bond between macrocycle and carbohydrate fragments. It showed that synthesized compounds fluoresce intensely inside HeLa cells, which enable these compounds to be considered as potential diagnostic agents and indicates their ability to remain in the cell in an unassociated photoactive state — a necessary condition for the realization of a photodynamic action. It was determined that while all conjugates had comparable photoinduced toxicities, the conjugate with phorbin macrocycle fragment had a much lower dark toxicity, which corresponds to the trends noted earlier. In terms of a therapeutic window, conjugate significantly exceeds similar derivatives of chlorin [Formula: see text] and is the most promising for further research.