Vincristine-induced neuropathy as the initial presentation of Charcot-Marie-Tooth disease in acute lymphoblastic leukemia: A Pediatric Oncology Group study

Purpose: After profound peripheral neurotoxicity during induction chemotherapy for acute lymphoblastic leukemia (ALL) in the index patient with Charcot-Marie-Tooth hereditary neuropathy (CMT), study coordinators of the Pediatric Oncology Group (POG) front-line ALL protocols reviewed patient registrations to identify any other patients with possible CMT. The goal was to provide preliminary information about patients with undiagnosed CMT who develop ALL. Patients and Methods: Five children with ALL who were enrolled in POG B-precursor or T-cell ALL protocols from 1994 to 1999 subsequently were determined to have CMT hereditary neuropathy. Their clinical presentations and treatment records were reviewed in detail. Records of all patients entered on POG 9201 (lesser-risk ALL) were reviewed to identify all cases of significant vincristine toxicity noted in the first 6 months of treatment. Results: The five identified patients all had substantial peripheral neurotoxicity that required alteration in treatment and/or orthopedic/physical therapy evaluation and follow-up. The POG 9201 review identified 25 of 686 patients (3.6%) with significant peripheral neuropathy. Three of 25 were diagnosed with CMT; the others have had no testing reported. Conclusions: A family history of CMT or other peripheral neuropathy should be sought at the time of diagnosis of ALL. Testing for CMT should be considered in any child with substantial vincristine-induced peripheral neurotoxicity. Treatment of such patients must be individualized. Testing of all patients with significant peripheral neuropathy would be necessary to determine the percentage of such neuropathy explained by underlying CMT.