Charlson Comorbidity Index (CCI) score to predict early reduced relative dose intensity in patients receiving oxaliplatin for colorectal cancer.

Abstract

e18125 Background: Colorectal cancer (CRC) is commonly treated in both adjuvant and palliative settings with Oxaliplatin. Painful peripheral neuropathy resulting in dose adjustments is a well recognized side effect in up to 30% of cases. Relative dose intensity (RDI), an expression of the percentage of planned dose received at a scheduled time, is a tool used to measure how closely a prescription has been adhered to. Studies have suggested a decreased RDI (<85%) is associated with inferior outcomes. The aim of this study was to calculate the RDI for CRC patients undergoing treatment with Oxaliplatin, to investigate reasons for dose delays and reductions and to calculate a Charlson Co-Morbidity Index Score (CCIS) for each patient Methods: CRC patients treated with Oxaliplatin from 2010-2016 within the BSHC were identified using pharmacy lists and pathology reports. The following exclusion criteria were applied: non first line Oxaliplatin and excluding cycles after three months. Data was obtained through a systematic, retrospective chart review. An audit of the chemotherapy prescriptions allowed the RDI to be calculated and the CCIS was calculated using a colorectal specific Index previously described. Results: We identified 176 eligible patients, 83 charts were available for review and 69 charts contained all necessary information to be included. Xelox (61%), Folfox-6 (35%) and Flox (4%) were the chemotherapy agents involved in this study. The average RDI achieved was 87.47%, with a range of 25%-103.17%. The primary cause for dose adjustments was peripheral neuropathy (64%). The CCIS range was 0 -3, with results demonstrating a significant connection between a higher CCI and lower RDI, see table 1. Conclusions: A CCIS ≤ 1 correlates to achieving a higher RDI, with each of these subgroups achieving above the acceptable cut off for RDI (>85%), as such certain co-morbidities may be early predictors of reduced RDI. [Table: see text]