Survival and recurrence in stage II endometrial cancers in relation to uterine risk stratification after introduction of lymph node resection and omission of postoperative radiotherapy: a Danish Gynecological Cancer Group Study

Objective: To evaluate survival and recurrence in stage II endometrial cancer in relation to uterine risk stratification. Outcome for stage II was compared before and after the introduction of lymph node (LN) resection and omission of all postoperative radiotherapy. Methods: The cohort consisted of 4,380 endometrial carcinoma patients radically operated (no visual tumor, all distant metastasis removed) (2005-2012) including 461 stage II. Adjusted Cox regression was used to compare survival and actuarial recurrence rates. Results: Uterine risk factors (low-, intermediate-, and high-) were the strongest predictors of survival and recurrence in stage II. Stage II low-risk having a prognosis comparable to low-risk stage I (grade 1-2, <50% myometrial invasion), whereas cervical invasion significantly increased the risk of recurrence and decreased cancer-specific survival in intermediate- and high-risk compared to the corresponding stage I risk groups. In 355 cases of 708 with cervical stromal invasion, LN-resection showed 27.9% with LN metastasis and upstaged 18.1% from stage II to IIIC resulting in longer survival and lower recurrence in LN-resected compared to non-LN resected stage II. Radical as compared to simple hysterectomy did not alter survival. Treatment with external beam radiotherapy decreased local recurrence without affecting survival. Conclusion: Uterine risk groups are the strongest predictors for survival and recurrence in stage II patients and should be considered when advising adjuvant therapy. LN-resected stage II had increased survival and decreased recurrence. Omitting radiotherapy increase vaginal recurrence without affecting survival.