Gynecologic oncology 2004-03
A phase III trial of surgery with or without adjunctive external pelvic radiation therapy in intermediate risk endometrial adenocarcinoma: a Gynecologic Oncology Group study.
Abstract
Background
Despite their low risk for recurrence, many women with endometrial adenocarcinoma receive postoperative radiation therapy (RT). This study was developed to determine if adjunctive external beam irradiation lowers the risk of recurrence and death in women with endometrial cancer International Federation of Gynaecology and Obstetrics (FIGO) stages IB, IC, and II (occult disease).
Methods
Four hundred forty-eight consenting patients with "intermediate risk" endometrial adenocarcinoma were randomized after surgery to either no additional therapy (NAT) or whole pelvic radiation therapy (RT). They were followed to determine toxicity, date and location of recurrence, and overall survival. A high intermediate risk (HIR) subgroup of patients was defined as those with (1) moderate to poorly differentiated tumor, presence of lymphovascular invasion, and outer third myometrial invasion; (2) age 50 or greater with any two risk factors listed above; or (3) age of at least 70 with any risk factor listed above. All other eligible participants were considered to be in a low intermediate risk (LIR) subgroup.
Results
Three hundred ninety-two women met all eligibility requirements (202 NAT, 190 RT). Median follow-up was 69 months. In the entire study population, there were 44 recurrences and 66 deaths (32 disease or treatment-related deaths), and the estimated 2-year cumulative incidence of recurrence (CIR) was 12% in the NAT arm and 3% in the RT arm (relative hazard (RH): 0.42; P=0.007). The treatment difference was particularly evident among the HIR subgroup (2-year CIR in NAT versus RT: 26% versus 6%; RH=0.42). Overall, radiation had a substantial impact on pelvic and vaginal recurrences (18 in NAT and 3 in RT). The estimated 4-year survival was 86% in the NAT arm and 92% for the RT arm, not significantly different (RH: 0.86; P=0.557).
Conclusions
Adjunctive RT in early stage intermediate risk endometrial carcinoma decreases the risk of recurrence, but should be limited to patients whose risk factors fit a high intermediate risk definition.
Related Questions
What is the optimal approach for a younger female with borderline resectable cervix cancer who may need adjuvant radiation, in light of a medical history significant for ulcerative colitis?
It all depends on the colitis status on therapy including the extent and response to ongoing treatment. No induction chemo. Either radical hysterectomy with the possibility of adjuvant RT or definitive RT based on colitis status. If high risk with RT, would proceed with surgery.
Do you follow GOG, ASTRO, or PORTEC recommendations for adjuvant therapy in stage I endometrial cancer patients?
I believe the current ASTRO guidelines encompass the older GOG and PORTEC guidelines for the most part and we follow these guidelines though we review all for the sake of completeness.For the first patient, barring other risk factors, I would offer adjuvant vaginal cuff brachytherapy; for the second...
In patients diagnosed with endometrial cancer who do not undergo SLNB or LND at the time of hysterectomy, what criteria is used to recommend completion surgery for LN assessment?
The value of nodal dissection was negative for survival in two trials and PORTEC 1 and 2 (no nodal staging), and GOG 99 (nodal staging) didn’t show any difference in nodal recurrence for most endometroid stage I cancer. Unless management would change, we usually limit redo surgical staging to advers...
Would you change your approach to adjuvant radiation for an incompletely staged, at least IB, grade 1 endometrial cancer, if a uterine perforation occurred at time of surgery?
Similarly to the above authors, I agree with offering this patient vaginal brachytherapy. Though she does not definitively meet GOG99 criteria, given the situation with deep myometrial invasion and perforation, this is a reasonable and low-risk treatment opportunity to decrease local recurrence. The...
Do you offer vaginal cuff brachy alone, vaginal cuff brachy and chemo, or WPRT for surgically staged IB grade 3 endometrial cancer?
All patients who have stage IBG3 fall into the GOG249 eligibility criteria. However, it is important to recognize that patients within this group have broadly varying risks. First of all, serous cancers (which have a greater propensity to spread intraperitoneally and may demand variant-specific appr...
Do the number of lymph nodes removed in a non-Stage IA/FIGO 1 endometrial cancer case, affect your decision for WPRT v. vaginal brachytherapy alone?
Yes, in some cases it does—for two reasons. If a patient has had an extensive negative node dissection, the risk of extravaginal pelvic failure is undoubtedly less and the risk of RT complications may also be greater than if the patient had hysterectomy only. These factors define the “therapeutic ga...
When is it appropriate to use adjuvant whole pelvis radiotherapy for Stage I endometrial adenocarcinoma?
The indications have been changing with the publications of GOG 99, PORTEC 1 and 2 , the Swedish and ASTEC studies, and the interpretation of data with the confounding factor of nodal dissection.At present, I would/do consider pelvic RT for Stage IB with grade 3 disease and Stage Ia with grade 3 and...