Frequency and Determining Factors of Empiric Chemotherapy Dose Reduction in Patients with Non-Small Cell Lung Cancer

Objectives: To determine the frequency and key factors regarding empiric chemotherapy dose reductions (ECDR) in nonsmall cell lung cancer (NSCLC) patients. Methods: This retrospective study involved the chart review of all histologically confirmed NSCLC patients receiving chemotherapy at the Odette Cancer Centre, Sunnybrook Health Sciences Complex, from 2013-2014. The frequency of ECDR and potential impacting factors were recorded and analyzed on SPSS v16.0. Results were expressed in percentages, P-values, and Cramer's V. Results: Our findings (N = 134) suggested patients with moderate kidney disease stages were statistically associated with ECDR (29% vs. 24% vs. 50% for stage I, II, and III respectively, p = 0.031, φc = 0.235, df = 2). Patients aged 61 and above (39% vs. 14%, P = 0.001, φc = 0.23, df = 1), polypharmacy of 4 or more medications (24% vs. 44%, p = 0.017, φc = 0.21, df = 1), presence of kidney disease (43% vs. 24%, P = 0.024, φc = 0.20, df = 1), and palliative intent (40% vs. 12%, p = 0.0027, φc = 0.26, df = 1) showed statistically significant, but weak association with ECDR. Combinations (3 or more) of the impacting factors as mentioned above showed statistically significant association with ECDR (75% vs 42%, P = 0.00, φc = 0.308). The degree of ECDR were positively correlated to patient age, moderate stage chronic kidney disease, and having combinations of impacting factors. Conclusions and Relevance: ECDR was common in the NSCLC patients (33%), particularly in the elderly, polypharmacy, palliative care and kidney disease population. Variances might exist among physicians, which might lead to clinically significant outcomes. Guidance and future studies for ECDR is crucial especially as Ontario's senior population grows.