Definitive radiotherapy for carcinoma of the vagina: outcome and prognostic factors.

PURPOSE

Primary carcinoma of the vagina is an uncommon tumor. Because of the long-standing interest in this disease at our institution a substantial number of patients with this disease has been accumulated, and this retrospective review was performed to define disease outcome, to delineate significant prognostic factors, and to provide treatment guidelines.

METHODS AND MATERIALS

This was a retrospective review of 301 patients with vaginal carcinoma (271 with squamous cell and 30 with adenocarcinoma) who received definitive radiotherapy between 1953 and 1991. Prognostic factors for outcome (local control, pelvic control, metastatic relapse, survival, and complications) were evaluated using univariate and multivariate techniques.

RESULTS

Patients disease was staged using the International Federation of Gynecology and Obstetrics (FIGO) system, and stages were distributed as follows: 0, 37 (12%); I, 65 (22%); II, 122 (40%); III, 60 (20%); and, IVA, 17 (6%). Treatment varied according to stage, with brachytherapy predominating for early disease but external beam playing a prominent role for more advanced disease. Patients with in situ disease received brachytherapy alone or transvaginal orthovoltage irradiation. For Stage I, brachytherapy alone was used in 25, external beam and brachytherapy in 38, and transvaginal alone in 2. For Stage II, brachytherapy alone was used in 20, external and brachytherapy in 66, and external irradiation alone in 36. For Stage III, external and brachytherapy was used in 15, and external alone in 45. Two patients with Stage IVA received brachytherapy alone, 10 received a combination of external and brachytherapy, and 6 received external irradiation alone. Total doses ranged from 10 to 154 Gy (mean 74.7 Gy, median 70.0 Gy), but only 18 (6%) received less than 55 Gy. At a median follow-up of 13 years, the 5-, 10-, 15-, 20-, and 25-year survival rates were 60%, 49%, 38%, 29%, and 23%, respectively. Beyond 5 years the survival rates relative to those for age-matched females in the general population were between 50 and 65%. Actuarial local recurrence rates were 23%, 26%, and 26% at 5, 10, and 15 years. Actuarial pelvic relapse rates were 26%, 30%, and 31% at 5, 10, and 15 years, and metastatic rates at those times were 15%, 18%, and 18%. Adenocarcinoma (nonclear cell) was a significantly worse disease than squamous cell carcinoma. The major determinants of local control for squamous carcinoma were tumor bulk (specified by size in centimeters, or by FIGO stage), tumor site (upper lesions faring better than others), and tumor circumferential location (lesions involving the posterior wall faring worse). Tumor bulk was an important determinant of metastatic relapse, but failure to achieve local control was also an independently significant determinant of metastases. Salvage after first relapse was uncommon and the survival rate at 5 years after relapse was only 12%. Serious complications occurred in 39 patients with an actuarial incidence of 19% at 20 years.

CONCLUSION

Vaginal carcinoma poses a formidable therapeutic challenge. The disease is heterogeneous with respect to its prognostic factors. Nonclear cell adenocarcinoma has an extremely poor prognosis and should be distinguished from squamous carcinoma. Both external beam and brachytherapy play crucial roles in management and most patients with disease beyond in situ should receive a significant component of external irradiation prior to brachytherapy.