The efficacy of postoperative vaginal irradiation in preventing vaginal recurrence in endometrial cancer.

Between 1960 and 1985 hysterectomy was performed on 811 FIGO stage I and 116 stage II endometrial cancers which were divided into three groups: low-risk stage Ii (grade 1 and 2 lesions confined to the inner third of the myometrium; high-risk stage Iii (grade 3 and/or invading to the middle third of the myometrium or beyond); and FIGO stage II tumors (also high-risk). Hysterectomy was the only treatment in 492; in 145 the vaginal vault alone was radiated and in 290 the whole vagina, in each instance by an intracavity dose of 60Gy; in 34 of the latter high-risk tumors the pelvis received an additional 46Gy by external beam therapy. Forty isolated vaginal recurrences were detected; 10 in 308 low-risk and 22 in 184 high-risk tumors treated by surgery alone, and two and five in 40 low and 105 high-risk patients, respectively, who received adjuvant vault irradiation. No recurrences followed irradiation of the whole vaginal mucosa in 163 stage Ii low-risk and 40 stage II lesions and one, 9 years later, in 87 high-risk stage Iii tumors. Nearly 45% of patients with vaginal recurrence died from cancer within 1 year, 77% within 5 years and only 10% survived their recurrence 10 years. Total vaginal irradiation eliminated vaginal recurrences in low risk and reduced the incidence to 2.1% at 20 years after high-risk tumors.