G.P.94 Incidence and severity of peripheral neuropathy in children on vincristine – Do vitamin E levels change during treatment?

Abstract Chemotherapy induced peripheral neuropathy(PN) is a common dose limiting side effect associated with vincristinetreatment. The painful sensori motor neuropathyseen in vincristineis similar to that in vitamin E deficiency. To determine the incidence, severity and type of PN associated with vincristinechemotherapy in children and to determine the levels of Vitamin Ein the blood before and after starting vincristine. All children in the oncology unit of a tertiary paediatric hospital on vincristinewere included. A detailed history,specifically tailored neurological examination and nerve conduction studieswere performed and blood vitamin Elevels were measured at baseline and at 3, 6 and 12 months from the time of chemotherapy. Thirty patients were enrolled over a period of 12 months. The mean age of the children was 6.2 years. 14/28(50%) children had pre B acute lymphoblastic leukemia. Peripheral neuropathywas evident in more than 90% patients. The most common subjective features of PN were weakness seen in 39% and pain in 30% at 3 months. The most common objective finding was loss of ankle reflex seen in 57% at 3 months and reduced ankle reflex in a further 21%. The subjective weakness disappeared and the pain reduced at 12 months while the objective signs persisted. The most common autonomic feature was constipation seen in 43% at 3 months. The most common nerve affected was the deep peroneal nervewith axonal involvement in 82% of the subjects tested. The vitamin Elevels dropped significantly at 3, 6 and 12 months from baseline although they still remained within normal limits. More than 90% children on vincristinehad evidence of neuropathy. It was mild sensorimotor axonal neuropathy that appeared within 3 months of treatment in most. The levels of vitamin Eremained in the normal range though there was a significant drop at 3 months, followed by values lower than baseline at 6 and 12 months.