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Bladder cancer, occurring at different times after radiation therapy for tumors of the pelvic organs (cervical cancer, uterus cancer, prostate cancer) is a specific problem of oncourology. The main visual manifestations of the adverse events of radiation therapy in early time after irradiation are pronounced edema and hyperemia of the bladder mucosa, in the case of severe complications – hemorrhages. In years after radiation exposure atrophic changes of the mucous membrane, telangiectasia and reduction of the capacity of the bladder occur; late complications of a severe degree manifest as ulcers and fistulas. The main clinical symptoms of bladder cancer are hematuria and dysuria. The cystoscopy still remains the “gold standard” for its diagnosis, but this method appears to have significant limitations if a tumor arises in bladder tissue suffering from radiation exposure. In this case, the clinical symptoms and the cystoscopic picture can be regarded as manifestations of the side effects of RT, especially in case of grade 3 and 4 of complication. Optical methods may play a key role for distinguishing between a metachronous bladder cancer and severe complications of radiation therapy. Optical coherence tomography (OCT) has a spatial resolution corresponding to several micrometers and makes it possible to assess the structure of biological tissues at a depth of up to 2 mm. Besides, polarization-sensitive methods OCT (CP OCT) allow evaluating the state of the connective tissue matrix which loses orderliness and organized structure of the arrangement of collagen fibers and bundles in malignant tumors. The study presents the case reports of bladder cancer which arose against the radiation-induced changes of bladder tissue after previous irradiation for cervical cancer and were diagnosed by optical coherence tomography.
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