In 20 ovarian cancer patients treated by cisplatin-based chemotherapy quantitative investigations of the vibration and the thermoperception were performed. Following the administration of cisplatin of 300 mg/m2 and more the vibration perception threshold (VPT) was shown to be significantly elevated in all patients, despite the absence of clinical symptoms and signs in a number of patients. The VPT returned within 8 months to its original level in the 2 patients who were followed after cessation of therapy (cumulative dose of cisplatin 450-525 mg/m2). The changes seen in hands and in feet were comparable. There was no significant difference between the left and the right hand side. Thermoperception thresholds did not change during the treatment period. This study shows that quantitative measurement of vibration perception thresholds in patients treated with cisplatin is a relatively simple, accurate and reliable technique. Measurement is only required at the hand. It is concluded that this technique is a valuable tool in the assessment of cisplatin neurotoxicity and may be used in the monitoring of drugs that claim to be of benefit in the prevention and treatment of this affliction.