Primary squamous cell carcinoma of the vagina treated by radiotherapy: a failures analysis--the M. D. Anderson Hospital experience 1955-1982.

The retrospective study concerns 167 patients with primary squamous cell carcinoma of the vagina treated at The University of Texas M. D. Anderson Hospital and Tumor Institute between January 1955 and December 1982. Of these 167 patients, 162 were evaluable and 5 were lost to follow-up. For small tumors, localized treatment by brachytherapy alone, transvaginal irradiation with 125 to 250 kV alone or in combination with brachytherapy, was mainly used, with emphasis on use of colpostats and transvaginal irradiation for tumors of the upper half of the vagina and interstitial (with radium needles or, later, afterloaded stainless-steel guides with iridium wires) for the lower half. For medium-size tumors, local treatment was combined with external irradiation, mainly using conservative-size fields. For the majority of larger tumors or when the anatomy was distorted, external irradiation alone was used, also with portals of conservative size. Failures were analyzed in relation to FIGO (International Federation of Obstetrics and Gynecology) staging, tumor location, and modality of treatment. As expected, central failures were higher in Stage III disease (9 of 38 patients, 24%) but also uncomfortably high for Stage I patients (13 of 71 patients, 18%) treated locally or with external and local irradiation. The incidence of central treatment failures in tumors of the lower vagina (13/51 patients, 25%) was somewhat higher than for tumors located in the upper vagina (13/85 patients, 15%), but the percentage of large tumors in the lower vagina was 53% compared with 31% in the upper vagina. Severe complications were related to high doses of irradiation alone or in combination with aggressive surgery, and to pelvic inflammatory disease.