Genitourinary Cancer

PV QA 4 - Poster Viewing Q&A 4

TU_16_3480 - Adjuvant Hysterectomy After Primary Chemoradiation for Stage IB2 Cervical Cancer: Response Rates, Complications and Outcomes in the HDR Era

Tuesday, October 23
2:45 PM - 4:15 PM
Location: Innovation Hub, Exhibit Hall 3

Adjuvant Hysterectomy After Primary Chemoradiation for Stage IB2 Cervical Cancer: Response Rates, Complications and Outcomes in the HDR Era
A. Pham1, S. X. Bian1, K. Matsuo2, A. H. Zhuang1, R. Jennelle1, and O. M. Ragab1; 1University of Southern California Keck School of Medicine, Department of Radiation Oncology, Los Angeles, CA, 2University of Southern California Keck School of Medicine, Division of Gynecologic Oncology, Los Angeles, CA

Purpose/Objective(s): Adjuvant hysterectomy (AH) for FIGO 1B2 cervical cancer after primary chemoradiation (CRT) is controversial. We aim to evaluate the morbidity and survival outcomes of AH and identify risk factors predicting for residual disease (RD).

Materials/Methods: We retrospectively reviewed 27 patients with mainly FIGO IB2 cervical cancer (95%) treated at a safety net hospital between March 2013 and May 2017. Patients received external beam radiation (XRT) with weekly cisplatin followed by HDR brachytherapy (BT) prescribed to Point A prior to planned AH. Toxicities were graded using to CTCAE v4.03. Dose to 90% of a retrospectively contoured high risk CTV (HR CTV D90%) was calculated. The 2 Gy equivalent dose (EQD2) to point A, HR CTV D90%, and organs at risk (OARs) were calculated using tumor α/β of 10 and 3 for OARs. Survival analysis was performed using Kaplan-Meier method with log-rank test. We used a logistic regression model to correlate tumor characteristics and treatment parameters with rates of complications and pathologic RD.

Results: The majority of patients were Hispanic (70%) or Asian (20%) with a median age of 45 years (IQR 40–56) and adenocarcinoma (50%), squamous (46%) and adenosquamous (4%) histologies. After 45Gy of XRT, HDR BT doses were 9Gy ×2, 6.5Gy ×3, and 8Gy ×3 in 55%, 15% and 15% of patients respectively, with a median point A EQD2 of 72.9 Gy (IQR 71.5 – 73.8 Gy). Median time to AH after completion of radiation was 51 days (IQR 45-56). Median follow-up time was 21 months (IQR 10-40). No patients have died at the time of analysis. The 2 year local control, distant metastasis free survival and disease free survival was 89%, 88% and 86% respectively. Rates of acute and late G0-1, G2 and G3 gastrointestinal (GI) toxicity were 65%, 45%, and 0% and 96%, 0%, and 4%, respectively. Rates of acute and late genitourinary (GU) toxicity were 87%, 13% and 3% and 92%, 4%, and 4%, respectively. Six (22%, 95% CI 7-38%) patients had G3 perioperative complications, mostly vaginal cuff dehiscence (n=4). All four women with dehiscence underwent AH using minimally invasive surgery (MIS). Point A and vaginal vault point doses, D0.1cc, D1cc and D2cc to the rectum and bladder, HR-CTV D90%, and time to AH did not predict for G3+ complications on univariate analysis. 19 of 27 (70%) patients had residual disease after AH. On multivariate analysis, only prolonged XRT duration correlated with increased rates of RD (p=0.041). A cut off of 48 days best predicted for RD with an AUC of 0.80 (95% CI 0.58-0.95). RD was not associated with age, histology, tumor size, grade, nodal disease, pre-CRT PET SUV, time to AH, or HR CTV D90%.

Conclusion: Patients with barriers that cause delays in completing their CRT are at higher risk for residual disease. These patients and others at risk for RD may benefit from AH, but perioperative morbidity can occur even with careful radiation planning and lowered treatment dose. Future directions include using MRI to identify those with RD that may benefit from AH and comparing the toxicity of MIS versus open AH.

Author Disclosure: A. Pham: None. S.X. Bian: None. A.H. Zhuang: None. O.M. Ragab: None.

Send Email for Anthony Pham


Assets

TU_16_3480 - Adjuvant Hysterectomy After Primary Chemoradiation for Stage IB2 Cervical Cancer: Response Rates, Complications and Outcomes in the HDR Era



Attendees who have favorited this

Please enter your access key

The asset you are trying to access is locked. Please enter your access key to unlock.

Send Email for Adjuvant Hysterectomy After Primary Chemoradiation for Stage IB2 Cervical Cancer: Response Rates, Complications and Outcomes in the HDR Era