The value of and indications for radiotherapy in endometrial carcinoma

Today the endometrial carcinoma is the most frequent malignant tumor found in female genital tract. Endometrial carcinoma ought to be operated in all cases, if possible. Traditionally some form of adjuvant radiotherapy has been given. Despite the large number of patients treated by combined therapy over the last 30 years, surprisingly there is a lack of hard data on which to establish a theory for an improved outcome. It is generally accepted that the risk of local relapses in the vagina is lowered when postoperative vaginal irradiation is applied. The question of the value of additional external irradiation in stage I endometrial cancer still is unsettled. Only two prospective studies led to the conclusion that only patients with poorly differentiated tumors and with deep infiltration of the myometrium might benefit from additional external radiotherapy. Therefore a simple score for these risk factors is proposed enabling assignment into patient groups of similar risk on the base of a point system due to individual prognostic factors. With a score of one to two points prognosis is very good and adjuvant irradiation seems not to be necessary. With three to four points local vaginal irradiation is recommended, with five and more points additionally external beam irradiation to the pelvis should be given. This is necessary in more than the half of the operated cases of endometrial carcinoma. The indication for such a treatment has become more individual and "high risk" cases are treated more intensively, but "low risk" cases have to be excepted from unnecessary adjuvant therapy. In order to judge an individual case of endometrial cancer histopathologic prognosticators have to be considered. Typical adenocarcinomas have a five-year survival of more than 80%, but unfavourable subtypes (adenosquamous, clear-cell, serous-papillary carcinomas) of only 40%, respectively. Tumor grading and depth of myometrial invasion are of high importance for individual prognosis. The new histopathologic staging system of FIGO (1988) takes these items into account. Only patients with severe internal diseases should be treated with radiation therapy alone. Although radiation therapy alone can cure endometrial cancer (five-year-survival approximately 60%), the survival figures are poorer than for the operation (five-year survival 80%, respectively). It should be outlined that in inoperable cases radiotherapy is the best form of treatment.