Radical radiation therapy for carcinoma of the vagina--impact of treatment modalities on outcome: Peter MacCallum Cancer Institute experience 1970-1990.

To determine the outcome of radical radiation therapy for carcinoma of the vagina, a retrospective analysis has been made of 103 patients referred with this diagnosis to the Peter MacCallum Cancer Institute from 1970 to 1989. Eighty-four patients were treated for cure, seventy-four patients with definitive radical radiotherapy and 10 patients with adjuvant post-operative radiotherapy. Results were analyzed from two eras--before and after 1985--reflecting changes in referral pattern, treatment policy, and outcome. Forty-eight patients were treated before 1985 (Stage I--24, Stage II--6, Stage III--15, Stage IV--3) and 36 patients after 1985 (Stage I--20, Stage II--3, Stage III--6, Stage IV--7). After 1985 more patients were treated with combined beam radiation and brachytherapy (23/36 vs. 16/48 prior to 1985). More extensive tumors were systematically implanted (Ir 192). (No implants before 1985; 15 implants and 8 intracavitary applications post 1985). Fewer were treated with external beam alone after 1985; 11/36 (31%) vs. 27/48 (55%) before 1985. A small number (7/84-8%) were treated with brachytherapy alone. Survival results were markedly improved after 1985 (22/36-61% vs 16/48-33%) due partly to the shorter period of follow-up, but due also to marked improvement in local control particularly in early stage disease. (1/23 vs. 12/30 recurrences in Stage I, II disease). Results indicate optimal results with radical radiation therapy occur only with adequate dose delivery best achieved with a judicious combination of external beam radiotherapy and brachytherapy. Interstitial implantation plays a crucial role.