[Clinical evaluation of the effectiveness of radiation treatment for cervical cancer].

The study is based on data on 1756 patients with cervical cancer treated as combined (remote + contact) and only the contact exposure with low, medium and high dose rate. For comparative radiobiological evaluation of reactions of irradiated tissues there were used the following radiobiological models: factor time-dose-fractionation, the cumulative radiation effect, linear- quadratic model in the variant of biologically effective dose. Survival of cervical cancer patients undergone combined radiation treatment was determined by the stage of disease. In particular, the survival of patients with Stage IB cervical cancer was significantly higher than in Stages IIB and IIIB, while in Stage IIB was significantly higher than in Stage IIIB. Long-term results of radiation treatment of patients with Stage IB1 (T1b1N0M0) and Stage IIB (T2bN0M0) cervical cancer did not depend on whether the contact radiation exposure was combined or single. The most preferred component of radiotherapy in women suffering from cervical cancer was brachytherapy with high dose rate.

[Clinical evaluation of the effectiveness of radiation treatment for endometrial cancer].

The study is based on data on 306 patients with endometrial cancer treated as combined (remote + contact) and only the contact exposure with low, medium and high dose rate. For comparative radiobiological evaluation of reactions of irradiated tissues there were used the following radiobiological models: factor time-dose-fractionation, the cumulative radiation effect, linear- quadratic model in the variant of biologically effective dose. Survival of endometrial cancer patients undergone combined or only the contact radiation treatment was determined by the stage of disease. In particular, the survival of patients with Stage IB endometrial cancer (combined radiation treatment) was significantly higher than in Stage IC, while in Stage IB (contact radiation treatment) was significantly higher than in Stages IC and IIB. Long-term results of radiation treatment of patients with all Stages of endometrial cancer were significantly better by 16% when only the contact radiation treatment was performed. The most preferred component of radiotherapy in women suffering from endometrial cancer with severe comorbidities was brachytherapy with high dose rate both in the combined and only contact irradiation.

[Basic principles and results of brachytherapy in gynecological oncology].

The fundamental basics of contact radiation therapy (brachytherapy) for gynecological cancer are presented. During brachytherapy the principles of conformal radiotherapy should be implemented, the aim of which is to sum the maximum possible dose of radiation to the tumor and decrease the dose load in adjacent organs and tissues, which allows reducing the frequency of radiation damage at treatment of primary tumors. It is really feasible only on modern technological level, thanks to precision topometry preparation, optimal computer dosimetrical and radiobiological planning of each session and radiotherapy in general. Successful local and long-term results of the contact radiation therapy for cancer of cervix and endometrium are due to optimal anatomical and topometrical ratio of the tumor localization, radioactive sources, and also physical and radiobiological laws of distribution and effects of ionizing radiation, the dose load accounting rules.

[Clinico-radiobiological evaluation of radiation dosage and complications of radiotherapy for endometrial neoplasm metastasis to the vagina]. / Kliniko-radiobiologicheskaia otsenka velichiny luchevykh nagruzok i oslozhnenii pri radioterapii metastazov raka tela matki vo vlagalishche.

The data on 132 patients with metastases of endometrial carcinoma into the vagina (MECV) were analysed. They had received complex (remote + contact) and contact radiotherapy alone with low-, medium- and high dosage. The following radiobiological models were employed to assess tissue response: time-dose-fractionation factor (TDFF), cumulative radiation effect (CRE) and linear-quadratic dose effect equation (LQDE) ("extrapolated dose of response"). There was no correlation between survival and dose in excess of connective tissue tolerance calculated for each radiobiological model or a dose below tolerance limit. When dosage exceeded tolerance limit the incidence of early- and late-onset radiation injuries increased significantly. In MECV patients who had received primarily radiotherapy and surgery, early-onset radiation injuries occurred in cases of overdosage from the most recent exposure. When high-dose brachiatherapy was employed as a component of complex treatment, late-onset moist epithelite of the vagina could develop, irrespective of whether radiotherapy had been given or not and whether tolerance limit had been exceeded. Late-onset injuries were recorded in cases of over-dosage who had received both radiation and surgery for primary endometrial carcinoma.

[Clinical evaluation of the effectiveness of radiotherapy for metastasis of cervical cancer to the vagina]. / Klinicheskaia otsenka éffektivnosti luchevogo lecheniia metastazov raka sheiki matki vo vlagalishche.

The study presents an analysis of the data on 137 patients with cervical carcinoma metastases to the vagina (CCMV) treated with both combined (distance + contact) radiation and contact radiation alone administered in low, medium and high dose. Tumor response was evaluated on the basis of the following radiobiological modalities: time-dose-fractionation, cumulative radiation effect and linear-quadratic ("extrapolated dose of response"). The investigation established a correlation between survival and primary tumor stage rather than size of metastasis. There was no relationship between survival and the regime of therapy (combined or contact one alone). High-dose brachiatherapy proved to be the best component of intracavitary irradiation. There was no correlation between radiotherapy efficacy and regimen (surgery, combined therapy or radiation) in the management of primary cervical carcinoma.

[Clinical evaluation of the effectiveness of radiotherapy in vaginal metastases of uterine cancer]. / Klinicheskaia otsenka éffektivnosti luchevogo lecheniia metastazov raka tela matki vo vlagalishche.

The data on 132 patients with metastases of endometrial carcinoma into the vagina (MECV) were analysed. Among the modalities used were complex (remote + contact) and contact radiotherapy with low-, medium- and high dosage. The following radiobiological models were employed to assess tissue response: time-dose-fractionation factor, cumulative radiation effect and linear-quadratic dose effect equation ("extrapolated dose of response"). There was a correlation between five-year survival in radiation-treated patients and metastasis size. Stage of disease proved a major prognostic factor in MECV treatment. Complex radiotherapy was of crucial importance in MECV treatment whatever the size of disseminated tumor. There was no correlation between efficacy of MECV treatment and therapy used to treat primary endometrial carcinoma (surgery, combined or radiotherapy).

[Clinical evaluation of radiation complications with various methods of radiotherapy for vaginal cancer]. / Klinicheskii analiz luchevykh oslozhnenii pri razlichnykh metodakh radioterapii raka vlagalishcha.

The investigation was concerned with complications development in 133 cases of primary vaginal carcinoma (VC) who had been treated with combined (distance and contact treatment) or low-dosage (LD), medium-dosage (MD) or high-dosage (HD) contact irradiation. Time-dose-fractionation (TDF), cumulative radiation effect (CRE) and linear-quadratic (LQ) ("extrapolated dose of response") were used to evaluate normal tissue response. Early- and late-onset radiation injuries of vaginal mucosa, urinary bladder and rectum were compared vis-a-vis dosage which was calculated on the basis of HDF model. Dosage exceeding the limits of connective tissue tolerance was responsible for the development of early-onset epithelitis, cystitis and rectitis in cases of LD- or MD-brachytherapy of vaginal carcinoma or when the latter was conducted in conjunction with distance therapy. However, early-onset epithelitis and cystitis might appear when dosage remained within tolerance limits. This occurred as a result of HD-contact treatment or when the latter was used as a component of combined therapy. Most late-onset moist vaginal epithelites, rectites and recto-vaginal fistuals were caused by dosage in excess of tolerance. Late- and early-onset vaginal epithelitis was observed with tolerable dosage, too, if HD-brachytherapy alone was used or as a component of combined treatment.

[Current methods in brachytherapy of female genital malignancies]. / Sovremennye aspekty brakhiterapii zlokachestvennykh opukholei zhenskikh polovykh organov.

The procedures of computed brachytherapy using Co-60; Cs-137 and Ir-192 sources of radiation are discussed. The standards for designing contact radiotherapy, including three-dimensional systems, and principles of monitoring chosen schedules are presented. Criteria for identifying equivalent radiation doses on the basis of the existing radiobiological schedules involved in brachytherapy using different dosage are evaluated. The results of radiation treatment of cervical and vaginal cancers versus tumor process extension are presented.

[Current techniques of brachytherapy in primary and metastatic cancers of the vagina]. / Sovremennye tekhnologii brakhiterapii pervichnogo i metastaticheskogo raka vlagalishcha.

The results of brachytherapy of 133 patients with primary vaginal carcinoma (stage I-III), 137--with cervical metastasis into the vagina, and 132 cases of endometrial metastasis into the vagina are presented. Recommendations based on a detailed analysis of isodose distribution versus the applicator type and radiation source used are given. The annular colpostat using 137cesium radiation from the Selectron NMD/SMD installation and 197iridium radiation from the MicroSelectron unit produces the maximum mean reference isodose. The uniform distribution of 100% isodose in exophytic and mixed neoplasms and the best mucosal focus and applicator volume/target volume ratio are obtained.

[Clinical evaluation of the effectiveness of radiotherapy for vaginal tumors]. / Klinicheskaia otsenka éffektivnosti luchevogo lecheniia raka vlagalishcha.

The report deals with the data on 133 patients with primary tumors of the vagina treated with both combined (tele- and contact gamma therapy) and contact treatment using low, medium and high dosage. The following radiobiological models were used for evaluating and comparing responses of normal tissue: time-dose fractionation, cumulative radiation effect and linear-square law model referred to as the "extrapolation-related dose of response". The results suggest that combined radiotherapy using high-dose contact treatment be recommended for localized stage I-II tumors while cases of stage III tumor should receive only combined radiotherapy provided brachitherapy uses modern radiation equipment which will assure a minimal gap between the nominal and actual characteristics of irradiation.

[Clinical and radiobiologic evaluation of radiation dosage in radiotherapy of vaginal cancer]. / Kliniko-radiobiologicheskaia otsenka velichiny luchevykh nagruzok pri radioterapii raka vlagalishcha.

The investigation has been concerned with the results of combined (distant + contact) treatment and contact low-, medium-, and high-dosage radiotherapy alone in 133 patients with primary tumors of the vagina (VT). Time-dose-fractionation (TDF), cumulative radiation effect (CRE) and linear-quadratic (LQ) ("extrapolated dose of response") models were employed to evaluate the response of normal tissue. There was no correlation between survival in VT patients treated with radiation only and the tolerance limits for connective tissue estimated using TDF, CRE and LQ models being exceeded. The incidence of late-onset radiation injuries rose significantly by 20% (p < 0.05) when the TDF- and CRE-based limits of tolerance were exceeded. The LQ model had no similar predictive value. The TDF model proved more convenient in radiobiological assessment of different patterns of total focal dose fractionation, selection of similarly effective modalities as well as in prediction of late-onset radiation injury.