Abstract P6-06-51: Multivariate analysis of factors effecting overall survival in minority based population of breast cancer patients receiving neoadjuvant chemotherapy: A single institution experience
Authors: Shah M , Jain S , Abhijai S 
Published: August 2014

Overall survival(OS) in breast cancer is influenced by age, gender, receptor status and stage at diagnosis. However, in minority-based populations, effect of the above factors on OS in patients receiving neoadjuvant chemotherapy has not been studied in any detail. Hence, we undertook this retrospective study.

1770 patients with breast cancer treated at John H. Stroger Hospital of Cook County between January 2000 and December 2012 were retrospectively analyzed after IRB approval. 225 patients who received neoadjuvant chemotherapy were included in the study. 30 of 225(13.3%) achieved pathologic complete remission (pCR). 101of 225(44.8%) achieved nodal remission (NR). Effects of age, race, stage, receptor status and type of chemotherapy on OS were evaluated using standard statistical multivariate analysis.

In our population, 108 0f 225(48%) were African American, 32 of 225(14.2%) were Caucasians, 61 of 225(27.1%) were Hispanics. 16 of 225(16%) were younger than 40 years of age. 160 of 225(71.1%) were stage III, 60 of 225(26.6%) were stage IV. 114 of 225(50.6%) were Estrogen receptor (ER) positive, 97 of 225 (43.1%) were Progesterone Receptor (PR) positive and 58 of 225(25%) were Her-2 overexpressed of which 53 received Transtuzumab based chemotherapy. 5 patients did not receive trastuzumab mostly because of the diagnosis prior to 2003 when the institution started to use trastuzumab in neoadjuvant setting.

In the pCR group the mean age at diagnosis was 48 years.18 of 30(60%) were clinical Stage III and 2 of 30(6.6%) were stage IV at diagnosis. 9 of 30(30%) were ER positive, 8 of 30(27%) were PR positive, 13 of 30(43%) were HER-2 overexpressed. On univariate analysis for the entire group, ER positive status (p = 0.031, HR 0.615(0.316-0.95), Her-2 positive status (p0.05, HR 0.569(0.325-0.999)) and Transtuzumab based chemotherapy (p = 0.03, HR 0.460(0.226-0.936)) were significantly associated with improved OS. On multivariate analysis, ER positive status was a single marginally significant independent predictor of improved OS (p = 0.07). The OS in pCR group was 88% at 5 years follow up. The NR group had significantly improved overall survival compared to the group not achieving NR (p = 0.01) and these results were consistent even when the group achieving pCR was excluded from NR group for comparison (p = 0.02). On the contrary, no statistically significant difference was found on overall survival with age, race, stage and type of chemotherapy.Our institution like any other public hospital serves the minority based population. ER and Her-2 positive status and Transtuzumab based chemotherapy are important prognostic variables for improved overall survival in this population. Though in our study 60% patients had stage III disease, the pathologic complete remission (pCR) rate is 13.3% in our population which is comparable to the national average of 7% to 25%.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-06-51.