Photodynamic therapy for preinvasive cervical cancer.

Abstract

6035 Background: Photodynamic therapy (PDT) is an effective treatment for various cancers ensuring maximum preservation of the viability of healthy tissues surrounding the tumor. The purpose of the study was to reveal the effectiveness of PDT in treatment for preinvasive cervical cancer. Methods: The study included 45 patients aged 22-53 years with preinvasive cervical cancer. The patients were divided into two groups depending on the type of the transformation area and the tumor site: group 1–on the exocervix (type I-II), n=24; group 2–on the endocervix (type III), n=21. Infection with high-risk genotypes of HPV (16, 18, 31, 33, 35, 45, 56) was detected with PCR in 37 (82%) women. All patients received PDT with the semiconductor Latus laser up to 3 W, a single-use diffusing fiber for the exocervix irradiation and a single-use cylindrical diffusing fiber for tumors in the cervical canal. Photoditazine and photolon were used as photosensitizers. Effectiveness criteria included the normalization of the colposcopic picture, the absence of atypical cells, and the pathogen elimination confirmed by PCR. Results: A normal cytogram profile was observed after PDT in 84% of group 1 and in 88% of group 2. PCR 3 months after PDT showed a positive HPV reaction in 9.1%. Neither group of patients had negative changes in cytogram after 6 and 12 months. Repeated HPV DNA tests detected HPV DNAs in 2.8% in group 1 and 3.2% in group 2. The effectiveness of PDT did not depend on the photosensitizer. The maximum follow-up period has lasted for 4.5 years, with no recurrences registered. During this period, three young women successfully gave birth to healthy children. Conclusions: PDT is an alternative treatment for pre-tumor and initial tumor pathology of the cervix with preservation of the anatomical and functional integrity of the organ, which is important for the female reproductive function. The results support the use of PDT in treatment for preinvasive cervical cancer.

Enhancement of Conventional and Photodynamic Therapy for Treatment of Cervical Cancer with Cannabidiol

“… 5 Since PDT is a very specific non-invasive localized treatment, with very few side effects and it has a short healing time with no scarring, as well as being suitable for repeated dosing, with little to no resistance being found, it seems to be a far more advantageous treatment for CC. 6 Current clinical phase studies by Gunaydin et al (2021), Li et al (2020), Afanasiev et al (2021) and van Straten et al (2017) have reported that CC ALA PS PDT has emerged as the most effective and harmless treatment strategy for the current control of CC, however it requires further investigation before this treatment can be marketed. 7 - 10 Additionally, even though the latest CC PDT clinical trials have shown the enormous potential, other preclinical trials indicate that there is still room for improvement.…”

“… 5 PDT has numerous advantages over conventional therapies, since it is a very specific non-invasive localized treatment, with very few side effects, it has a short healing time with no scarring, and it is highly tolerant to repeated doses with little to no resistance. 6 Furthermore, PDT may be considered for patients as an alternative treatment, as it allows them to preserve their fertility, whereas surgery, chemo- and radiotherapy often induce sterility in patients. 5 …”

“… 5 Furthermore, PDT is known to be a very specific non-invasive localized treatment, with fewer side effects, shorter healing times and reduced resistance to repeated dose treatments, when compared to conventional treatments. 6 Current ongoing clinical trials have reported that PDT therapy with 5-aminolevulinic acid (ALA) has emerged as an effective and tolerable treatment strategy for the control of CC. 7 - 10 Nevertheless, these clinical trials require improvement in relation to investigating enhanced PDT treatment to activate specific immune responses to fully eradicate CC secondary migration.…”

The evolution of clinical guidelines for antimicrobial photodynamic therapy of skin

“…The treatment of Infectious disease using PDT is a relatively recent application that does not discriminate between strains that are and are not resistant to antibiotics [ 51 , 52 ]. PDT requires a photosensitiser or pro-drug to be applied topically, intravenously or by an expanding range of other routes including oral, intra-auricular injection and transvaginal fibre [ 53 ]. In wound infection and healing, it is vital that the photosensitiser is applied topically to maximally preserve vasculature to the site [ 54 ]-residual product in the proximal capillaries and arterioles following systemic delivery could lead to their destruction during illumination of a site with deeply penetrating light.…”

A singlet oxygen self-reporting photosensitizer for cancer phototherapy

“…1,2 With the development of clinical treatment, photodynamic therapy (PDT) has drawn more and more attention due to the unique advantages of noninvasiveness, spatiotemporal accuracy and synergism. [3][4][5][6][7] The photosensitizers (PSs), as crucial elements, can transfer the endogenous oxygen to reactive oxygen species (ROS) for therapy. [8][9][10][11][12] In particular, benzo[a]phenoselenazinium (NBSe) has potential for efficient cancer phototherapy, thanks to its ultrahigh singlet oxygen quantum yield (F D ) in light and nontoxicity in the dark.…”