Dose Delays, Dose Reductions, and Relative Total Dose Intensity in Patients With Advanced Cancer Who Exercised During Neoadjuvant Chemotherapy Treatment

Abstract

Background: When it comes to chemotherapy, maintaining the dose and schedule of treatment are of vital importance, as clinical evidence suggests that dose intensity is associated with optimal treatment outcomes for various tumors. Yet, reduced dose intensity is a common method of mitigating the chemotherapy-induced side effects. Exercise has been shown to attenuate chemotherapy-related symptoms that frequently cluster together. Understanding this, we conducted a retrospective analysis in patients with advanced disease treated with adjuvant or neoadjuvant chemotherapy regimens and who completed exercise training during treatment.

Methods: Data were collected retrospectively in a chart review of 184 patients, aged 18 years or older and treated for Stage IIIA-IV cancer. Data collection included baseline patient demographics and clinical characteristics, including age at diagnosis, cancer stage at initial diagnosis, chemotherapy regimen, and planned dose and schedule. Cancer types included brain (6.5%), breast (35.9%), colorectal (8.7%), non-Hodgkin's lymphoma (7.6%), Hodgkin's lymphoma (11.4%), non-small cell lung (16.8%), ovarian (10.9%), and pancreatic (2.2%). All patients completed at least 12 weeks of prescribed, individualized exercise. Each program included cardiovascular, resistance training, and flexibility components, under the supervision of a certified exercise oncology trainer once a week.

Results: RDI was measured for each myelosuppressive agent in a regimen over the entire chemotherapy course and then averaged across the myelosuppressive agents in a regimen. An RDI of less than 85% was designated as the clinically meaningful threshold for reduction in RDI based on previously published studies.

Conclusions: A considerable proportion of patients across regimens had dose delays (18.3%-74.3%) and dose reductions (18.1%-84.6%). Between 12% and 83.9% of patients missed at least 1 dose of a myelosuppressive agent that was part of their standard regimen. Overall, 50.8% of patients received less than 85% of the RDI. In short, patients with advanced cancer and an exercise adherence above 84.3% saw fewer chemotherapy dose delays and dose reductions. These delays and reductions occurred significantly less frequently compared to the published norms in the sedentary population (P < .05).

Keywords: cancer; chemotherapy; dose delay; exercise.

Figure 1.

Pre- to post-changes in fitness parameters. Values are mean percent change ± standard error. *P < .05.