Prognostic Significance of Primary Tumour Factors in Stage III High Grade Endometrial Cancer
Harkiran Kaur, Lua Eiriksson, Reda Saad, Mahmoud Khalifa, Valerie Dube, Zeina Ghorab, Al Covens, Lisa Barbera, Nadia Ismiil. University of Toronto, Toronto, Canada
Background: The implications of surgical and pathologic findings in stage III high grade endometrial cancer (HEC) are controversial. Whether adjuvant treatment such as chemotherapy (CT) or radiation (RT) should be included based on high-risk primary tumour factors remains to be determined. This study sought to determine the contribution of primary tumour factors (PTF) versus treatment (TT) received in recurrence and survival outcomes.
Design: A retrospective cohort study was performed, including all patients with surgical stage III HEC treated at our institution (1999 - 2009). PTF assessed included: stage, histologic subtype, lymphovascular invasion (LVI), extent of myometrial invasion (MI), cervical (CI), serosal (SI), adnexal (AI), parametrial (PI) and vaginal (VI) involvement. Nodal status and margins (MR) were also assessed. Recurrence-free survival was calculated using the methods of Kaplan and Meier, and hazards ratios were determined using Cox proportional hazards modeling.
Results: The study included 82 patients (mean age = 66 ± 11 years) with surgical and pathologic stage III HEC (IIIA - 38%, IIIB - 7%, IIIC - 55%). The median follow-up duration was 22 months and median time to recurrence was 8.5 months. HEC comprised 24% grade 3 endometrioid, 23% carcinosarcoma, 22% mixed, 21% serous, 9% clear cell and 1% undifferentiated carcinoma. The prevalence of PTF assessed was: 74% deep MI, 27% SI, 52% CI (stromal), 48% AI, 6% VI, 5% PI, 85% LVI and 16% positive MR. Thirty-two percent of patients received pelvic with or without vaginal vault RT, 17% of patients received CT, and 35% of patients received both RT and CT. Fifty-nine percent of patients recurred (IIIA - 40%, IIIB - 12%, IIIC - 48%).
In univariate analyses, recurrence was associated with SI (p = 0.04), positive MR (p = 0.0003), CI (p=0.001) and histology (p = 0.01). When controlling for PTF and TT received, clear cell and carcinosarcoma histologic subtypes (HR 8.6 and 6.0, respectively) as well as cervical stromal invasion (HR 3.7) were associated with an increased risk of recurrence. Meanwhile, patients who received either CT or RT experienced significantly decreased risk of recurrence (HR 0.42 and 0.48, respectively).
Conclusions: When controlling for high-risk PTF and TT received, PTF such as histologic subtype and cervical stromal invasion are associated with risk of recurrence, while adjuvant treatment with CT, RT, or both, may decrease risk.
Category: Gynecologic & Obstetrics
Tuesday, March 20, 2012 9:30 AM
Poster Session III # 175, Tuesday Morning