Temporal, Location- and Symptom-Specific Likelihood of Patient-Reported Sensory Symptoms Related to Oxaliplatin-Induced Peripheral Neuropathy (OIPN) in Patients Receiving Oxaliplatin for Three Months.

ABSTRACT

While oxaliplatin-induced peripheral neuropathy (OIPN) is more common and severe in patients who receive the previous standard, 6-month oxaliplatin-based treatment, we hypothesized that OIPN was still pervasive in patients who received shorter, 3-month-treatment regimens. Using six EORTC QLQ-CIPN20 questions that quantify numbness (N), tingling (T) and shooting/burning pain (P) in upper/lower distal extremities, our aim is to quantify patient-reported responses over 3 months (6 cycles) of oxaliplatin regarding symptom-specific timing, location and severity. For each question, patients were asked how each of the sensory symptoms had affected them during the preceding week, with 1 = "Not at all", 2 = "A little", 3 = "Quite a bit" and 4 = "Very much". The proportional odds model for the cumulative log odds of response that allowed symptom-specific patient heterogeneity to be obtained was applied to a pooled dataset from the placebo arms of two multisite OIPN prevention trials and fit separately to the upper/lower distal extremities. For each symptom, we report the cycle-specific marginal probabilities for each response. In 141 patients, substantial patient heterogeneity in the likelihood, at a given cycle, of a more severe response for a symptom was present. Distinct patterns in the probabilities for each response over time for N and T were observed between the upper/lower distal extremities, while the probabilities of a response >1 for P was largely negligible in both locations. Despite the decrease in exposure to oxaliplatin from 6 to 3 months, OIPN was still pervasive with patients experiencing considerable N and T in the fingers (or hands) and toes (or feet).