Abstract P3-05-55: The Effects of Comorbidities on the Effectiveness of Neoadjuvant Chemotherapy in Breast Cancer
Authors: Friend Kara , Breese Rebecca , Pu Tracey , Wood Jasmine , Arif Fatima 
Published: March 2023

Abstract
Background: Neoadjuvant chemotherapy has been used in a variety of cancer treatments to transform inoperable tumors to operable tumors. Within breast cancer treatment, it has successfully been used to increase the rates of breast conservation therapy. Neoadjuvant chemotherapy is being used to downgrade locally advanced breast cancer, as well as treat inflammatory breast cancer, and node negative breast cancers with genetic expression profiling results that predict the need for adjuvant chemotherapy. There have been several studies that have evaluated the effects of age and comorbidities of patients with breast cancer on treatment decisions, particularly chemotherapy. However, very few studies have reviewed additional factors outside of tumor characteristics for predicting complete response to neoadjuvant chemotherapy. The purpose of this study is to determine if there are any patient factors, particularly comorbidities, that play a role in modifying chemotherapy regimens and if that affects the patient’s response to chemotherapy. Methods: A retrospective chart review was performed on patients between 18-89 years of age at the time of their breast cancer diagnosis, who underwent neoadjuvant between 1/1/2014 and 1/1/2019. Patients included were treated by Dr. Kara Friend or Dr. Jennifer Reed at Sentara Leigh Memorial Hospital. Data collected included demographics, tumor characteristics, treatment regimens (chemotherapy, radiation therapy, antihormone therapy, and surgery), noting when chemotherapy regimens had to be modified, pathologic response to neoadjuvant chemotherapy, and long term outcomes. Comorbidities were identifed and used to calculate the Charleson Comorbidity Index (CCI), which was used to categorize patients. Results: A total of 111 patients were reviewed. All patients were female and ages ranged from 24 to 84, with most patients being in their fourth or fifth decade. 30% of the patients had triple negative tumors, and 48% had HER2+ tumors. Most patients had invasive ductal carcinoma, with only 6 patients (5.4%) having invasive lobular carcinoma. 26 patients had positive genetic panels, 10 of which were BRCA positive. 28 patients had negative panels, and 57 were not tested. The most common chemotherapy regimens were TCHP, AC/T, and TCH. Two patient’s cycles were reduced from the beginning due to low ejection fractions, 3 were modified due to pulmonary reactions, 1 for renal failure, 1 for Hepatitis C activation, and 10 for neutropenia or infections. One patient self-discontinued chemotherapy in favor of alternative medicine. 65.7% of the patients underwent antihormone therapy. 27% of the patients underwent radiation. Most patients had CCI scores of 0. Of those with a CCI score of 0, 4 needed modified regimens (8.3%). Of those with a CCI score of 1, three needed modified regimens (10.3%). Of those with a CCI score of 2, three patients needed modified regimens (23.3%). Of those with a CCI score of 3 or greater, 8 needed modified regimens (38.1%) When evaluating the effect of a CCI of 0-2 compared to 3 or greater on likelihood of reduced chemotherapy, there was not a statistically significant result (p = 0.99). However, the appeared to be a trend of increasing need for modified regimen with increasing CCI score. When evaluating if a reduced chemotherapy regimen led to progression during neoadjuvant chemotherapy or no response, the result was not statistically significant (p=0.24). Conclusion: Our study suggests that an increasing CCI score corresponds to an increased likelihood of needing a modified regimen, however this result was not statistically significant. Increased comorbidities and the need for modifying chemotherapy regimens do not appear to have an effect on pathologic response to neoadjuvant chemotherapy. This study is limited by the sample size, and a greater sample size will be necessary to make further conclusions.
Citation Format: Kara Friend, Rebecca Breese, Tracey Pu, Jasmine Wood, Fatima Arif. The Effects of Comorbidities on the Effectiveness of Neoadjuvant Chemotherapy in Breast Cancer [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P3-05-55.