The experience of photodynamic therapy for early gastric cancer is described in the article. The treatment results in 68 patients who were excluded for convenient surgical treatment because of advanced age or severe co-morbidity are represented. 63 patients had single tumor, 5 patients – 2 tumors. Four Russian agents: photogem, photosens, radaсhlorin and alasens, were used for photodynamic therapy. The treatment session was performed under local anesthesia during routine endoscopy with diode laser with wavelength consistent with photosensitizer (photogem – 630 nm, photosens – 670 nm, alasens-induced protoporphyrin IX – 635 nm, radaсhlorin – 662 nm). The short-term results were analyzed 1 month after treatment according to endoscopy, morphological study, CT, ultrasound or endosonography. For 73 lesions complete regression was observed in 53 (72.6%) and partial regression in 20 tumors (27.4%). The efficacy of photodynamic therapy was shown to be directly associated with tumor size. Thus, for tumors up to 1 cm regression occurred in 100% of cases, up to 1.5 cm – in 70.8%, up to 3 cm – in 65.2%, up to 5 cm – in 58.3%. The median survival rates accounted for 7.31 years, 3-year survival – 83±5%, 5-year - 69±8%. The experience showed that the developed method of photodynamic therapy was promising in treatment for early gastric cancer as an alternative to surgery.

The results of treatment in 17 patients with morphologically confirmed resectable primary or recurrent retroperitoneal tumor using intraoperative photodynamic therapy with photogem (5 patients), radaсhlorin (7 patients) and photodithazine (5 patients). The drugs were administered intravenously in following regimen: photogem 48 h before surgery in dose 2.5–3.0 mg/kg, radaсhlorin and photodithazine – 0.7 and 0.7–1.0 mg/kg, respectively, 2–3 h before resection. Irradiation was performed to tumor bed after complete radical removal from one or several positions depending on tumor localization. The light dose accounted for 30 J/cm², duration of treatment session depended on area of irradiation. Two patients with recurrent tumor had two reoperations with session of photodynamic therapy. One patient had repeated recurrence requiring third surgery with photodynamic therapy. Thus, 17 patients underwent 25 sessions of intraoperative photodynamic therapy. There were no intraoperative complications. One patient had an early post-operative complication in the form of pancreonecrosis which could be associated with extended resection. The recurrence rate was 17.6%. The results showed safety of the method and affinity of utilized photosensitizers to retroperitoneal tumors of different histological types (sarcoma, gastrointestinal stromal tumor and others).

The results of investigation for photodynamic activity of new tetraazachlorin derivate – tetramethyltribenzotetraazachlorin, synthesized in Research Institute of Organic Intermediates and Dyes. The study was performed on female mice of СВА line. The tumor model was transferred solid ascetic sarcoma S-37. The samples of photosensitizer, previously solubilized in 10% aqueou s solution ofCremophor EL, injected to mice intravenously on the 7th day of tumor growth in dose of 1–2 mg/kg. Two hours later the irradiation of sensitized tumor using light emitting diode device in a maximal wavelength of 755 nm (light power density – 50 mW/cm², maximal total light dose – 300 J/cm²) was performed. The efficacy of photodynamic therapy was assessed by growth inhibition rates in the study group comparing with control group. The study showed that photodynamic therapy with investigated sample in dose of 2 mg/kg and light dose of 300 J/cm² significantly inhibited the tumor growth (inhibition rate of 70–80% within 20 days), indicating prospectivity of subsequent investigations of tetraazachlorin as photosensitizer for photodynamic therapy of malignant tumors.

The review of literature for current methods of endoscopic treatment for colon epithelial neoplasms is represented. Such types of endoscopic interventions as loop electroresection, submucosal dissection, coagulation and destruction of tumors and combination of several options depending on efficiency of previous therapy is analyzed. Limitations of every method, its special aspects and possible complications are described. Special focus is on specifics of neoplasms for which selected methods may be the most effective. Thus, hot biopsy and destruction using high-energy laser is efficient for small flat neoplasms, endoscopic electroexcision – far small pedunculated lesions, and fragmentation is adequate for exophytic tumors more than 2.0 cm. Long-term results of endoscopic treatment, recurrence rates after different options are represented. The literature for photodynamic therapy consists mostly articles about development (on pre-clenecal stage) of new photosensitizers which are effective for colon cancer, new methods of treatment including combination with hyperthermia in low-dose light irradiation etc. The literature data shows the prospectivity of subsequent developments in this field.

The case of successful combined modality treatment in patient with stage IIIB T_4bN₁M₀ breast cancer is reported. The first step included 2 courses of neoadjuvant polychemotherapy in CAF regimen with decrease of tumor size. The second step was irradiation (total dose of 45 Gy) of breast and areas of regional metastasis. The third step was radical mastectomy by Madden with polypositional intraoperative photodynamic therapy with photosens (the output laser power 1500 mW, light dose 30 J/cm², total time of irradiation – 25.6 min). The histological study of surgical specimen showed infiltrative ductal carcinoma with metastases in 3 nodes without fat invasion. In the post-operative period the patient had 3 courses of adjuvant chemotherapy in CAF regimen. Currently the duration of recurrence-free survival after treatment is 4 years.