Abstract P4-10-18: Patterns of failure in a predominately black, inner city cohort of triple negative breast cancer patients at a single institution
Authors: Rice SR , Cherng H-R , Hamza M , Murali S , Rosenblatt P , Bellavance E , Cheston S , Amin N , Nichols EM 
Published: May 2019

Introduction: Triple negative breast cancer (TNBC) accounts for 12-17% of breast cancer (BC) in the US, but behaves much more aggressively. It occurs more commonly in younger, black women and death within two years of diagnosis is more common in this subset of BC compared to hormone receptor positive BC. At the University of Maryland Greenebaum Comprehensive Cancer Center, we see a higher proportion of TNBC and present our comprehensive evaluation of the patterns of failure in women with TNBC treated at our urban breast center.

Materials/Methods: A retrospective review of TNBC patients treated from 2005-2017 identified 198 patients with Stage I (33%), Stage II (47%), Stage III (16%) and Stage IV (4%) TNBC. The patients were all female, median age of 54 years (range 22-86 years), 64% black, 40% married, 7% BRCA mutated, and 3% HIV positive. Tumor characteristics revealed 93% infiltrating ductal carcinoma, 68% grade 3, and 18% with lymphovascular space invasion. Self-palpation of the lesion occurred in 76% of women, and the lesion was in the upper outer quadrant 62% of the time. Thirty percent of pts had neoadjuvant and 67% adjuvant chemotherapy. Ninety-eight percent of pts underwent surgical resection, 55% had lumpectomy and 61% sentinel lymph node biopsy. Adjuvant radiation was given in 56% of patients with a median dose of 60 Gy (range 16-70 Gy). Chi-square testing was used to compare variables, while logistic regression with Kaplan-Meier estimate was used to calculate overall survival (OS) and freedom from recurrence (FFR).

Results: With a median follow up of 45 months, 33 (17%) documented failures occurred. At time of first documented failure, 30% were local (L), 6% regional (R), 22% distant (D), 6% combination of L/R, 12% combination of L/R/D, 9% L/D, and 15% R/D, with a total combined failure pattern in 42% of pts. There was no significant difference in failure patterns between white and black pts (p=0.50, Table 1). The 2 and 5 year OS was 88% and 80%, respectively. Median survival was not reached in our cohort. The 2 and 5-year FFR was 90% and 84%, respectively with a median time to any failure of 16 months after initiation of therapy and median OS of 29 months for these pts.

Conclusion: Our work shows that with modern BC therapies treatment outcomes for pts with TNBC are improved and 84% are free of disease at 5 yrs after the initial diagnosis. The patterns of failure in TNBC are complex, did not vary by race, and showed the largest proportion of our pts (58%) failing in distant and locoregional sites simultaneously, while an additional 30% of pts fail locally only. These failure patterns did not differ significantly based on race. Future efforts will identify pts most at risk for treatment failure for consideration of treatment intensification, as salvage options are limited when treatment failure occurs.

Comparison of Failure Patterns Between White and Black PatientsFailure PatternWhite (n,%)Black (n,%)p-valueLocal only2 (22.5)8 (33) Regional only1 (11)1 (4) Distant only2 (22.5)5 (21)p=0.496Local and Regional0 (0)2 (8) Local and Distant0 (0)3 (13) Regional and Distant3 (33)2 (8) Local, Regional and Distant1 (11)3 (13) 

Citation Format: Rice SR, Cherng H-R, Hamza M, Murali S, Rosenblatt P, Bellavance E, Cheston S, Amin N, Nichols EM. Patterns of failure in a predominately black, inner city cohort of triple negative breast cancer patients at a single institution [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-10-18.