Role of intracavitary cuff boost after adjuvant external irradiation in early endometrial carcinoma

Management of early endometrial carcinoma often consists of surgicopathologic staging followed by adjuvant radiation therapy (RT) for patients at risk of local recurrence. While an intracavitary vaginal cuff boost (VCB) is commonly given after external beam radiation therapy, its effects on local control and complication rates are unknown. To assess these effects, we reviewed 157 patients with FIGO Stage I (n = 134) or incidentally diagnosed (n = 23) endometrial adenocarcinomas. After surgery and external radiation therapy, 103 patients (65.6%) received a vaginal cuff boost of 3000-5000 cGy surface dose (Group I) and 54 (34.4%) did not (Group II). One hundred and two Group I and 52 Group II patients were evaluable for analysis. Median follow-up was 78.0 months for Group I and 60.0 months for Group II. Despite a preponderance of poor prognostic factors in Group II, no significant difference in local failure was seen. A component of local failure was seen in 6 Group I patients (6.0%) and 4 Group II patients (7.7%), p = 0.74. Distant failure, reflecting more advanced disease, was higher in Group II (19.2%) than in Group I (9.0%). Late complications included rectal bleeding/proctitis in 18.6% of Group I patients and 3.8% of Group II patients (p = 0.01). Overall, grade 2 complications occurred in 27.5% and 15.4% of Group I and II patients, respectively (p = 0.09). No difference in frequency of grade 3 complications was evident. Based on this retrospective study, intracavitary vaginal cuff boost after surgery and postoperative external beam radiation therapy does not appear to improve local control in early endometrial adenocarcinoma. Its possible effect on complication rates is uncertain.