Long-term neurotoxicity in patients treated with cisplatin, vinblastine, and bleomycin for metastatic germ cell cancer.

Thirty patients treated for germ cell cancer with six cycles of cisplatin, vinblastine, and bleomycin participated in a follow-up examination of neurotoxicity 49 to 106 months after treatment. Of these, 22 patients (73%) had sensory loss; half of them complained of paresthesias. The vibration perception threshold was increased in 24 patients (80%). Auditory stimulation revealed a normal latency of the first component of the brain stem-evoked potentials Pl but an increased interpeak interval between this and Pv; reflecting a central conduction defect. Motor conduction velocity (CV) along the peroneal nerve was normal. The average sural nerve CV was decreased (P less than .01) and the sensory action potential amplitude was reduced (P less than .01). Warm perception threshold was increased in 10 patients (33%). Cortical-evoked potentials after tibial nerve stimulation had increased latencies in 29 patients (97%). The peripheral CV along the tibial nerve was slowed (P less than .01) in 19 patients, and the central conduction time from Th12 to cortex was prolonged in 15 patients (P less than .01). The changes in conduction along peripheral and central pathways after tibial nerve stimulation are compatible with a toxic effect on the sensory root ganglia causing a "dying back" axonal degeneration of central and peripheral nerve fibers.