LATEBREAKER
Cancer
The Association of Oxaliplatin-Induced Peripheral Neuropathy, Sociodemographic, and Clinical Characteristics of Colorectal Cancer Patients with Chemotherapy Delay and Early Discontinuation Robert Hines* Robert Hines Stephanie Sutton Christopher Schoborg Shunpu Zhang Timothy Sumner
Background: The addition of oxaliplatin to the 5-fluorouracil (5FU)-based chemotherapeutic regimen in colorectal cancer patients has been shown to improve survival. However, oxaliplatin-induced peripheral neuropathy (OIPN) is the major dose-limiting toxicity with the hallmark symptom of “stocking and glove” peripheral sensory neuropathy. The purpose of this study was to assess the association between OIPN and other sociodemographic/clinical characteristics of older colorectal cancer patients with between-cycle delays in oxaliplatin administration and early discontinuation of treatment.
Methods: Colorectal cancer patients in this study were ≥ 66 years of age at diagnosis and obtained from the Surveillance, Epidemiology, and End Results database combined with Medicare claims data (SEER-Medicare). All subjects received at least two cycles of oxaliplatin. Diagnoses of OIPN and falls were defined according to diagnosis codes and were considered time-dependent exposures. Between-cycle chemotherapy delay was defined as a delay of ≥ 7 days between cycles. Early discontinuation was defined according to chemotherapeutic regimen (infusional 5-FU or oral capecitabine). Cox regression was used to obtain hazard ratios (HR) with 95% confidence intervals (95% CI).
Results: There were n = 4,566 patients available for analysis. OIPN was diagnosed during chemotherapy treatment in 4.9% (n = 225) of patients, and 1.0% (n = 45) subjects experienced a fall. Between-cycle oxaliplatin delay occurred for 57.7% of subjects (n = 2,633). OIPN was associated with a 36% increased rate of delay (HR = 1.36; 95% CI, 1.18-1.56) and having a fall was associated with a two-fold increased rate (HR = 2.02; 95% CI, 1.59-2.57). Female sex, high poverty, rural residence, and renal disease were also associated with an increased rate of delay. Early discontinuation was experienced by 24.6% of subjects (n = 1,124). OIPN was associated with a 90% increased rate of early discontinuation (HR = 1.90; 95% CI, 1.45-2.49). Female sex, older age, high poverty, noncolon tumors, and receipt of radiation all increased the rate of early discontinuation.
Conclusions: Fall prevention and therapeutics to prevent and treat OIPN are needed to decrease the likelihood of between-cycle chemotherapy delay and severe early discontinuation.