MALIGNANCY AND SENSORY NEUROPATHY OF UNEXPLAINED CAUSE - A PROSPECTIVE-STUDY OF 51 PATIENTS

Objective: To investigate the frequency of cancer developing in patien ts with peripheral sensory neuropathy of unexplained cause. Design: Pr ospective study. Setting: A neurologic unit in a general hospital. Met hods: Following the diagnosis of neuropathy, we searched for occult ma lignancy. This search was repeated together with neurologic evaluation s every 6 months thereafter. Patient recruitment began January 1, 1988 , and ended December 31, 1995. The end point of the study was December 31, 1996. Results: In the study period, we observed 363 patients with peripheral sensory neuropathy. Of these, 53 patients without any iden tified cause of neuropathy were invited to participate in the study. O f the 53, 2 patients refused. Thus, we examined and followed up 51 pat ients, 42 men and 9 women, with a mean age of 64.5 years (range, 19-80 years). The range between the onset of neurologic symptoms and the di agnosis of neuropathy was 2 to 72 months (mean, 13.9 months). The foll ow-up period ranged from 14 to 94 months (mean, 51.4 months). In 18 pa tients (35.3%) (16 men and 2 women) whose mean age at diagnosis of neu ropathy was 66.5 years. malignant growths were found 3 to 72 months (m ean, 27.4 months) after the onset of the neuropathy. The cancer was in the liver in 4 patients tall had a primary hepatoma), the bladder in 3, the lymph nodes in 3 tall with non-Hodgkin lymphoma), the prostate gland in 2, the lungs in 2 (small cell lung cancer in both), the breas t in 1, the pancreas in 1, the sublingual gland in 1, and the bone in l_(a metastatic sarcoma). Conclusions: More than one third of the pati ents with peripheral sensory neuropathy of unexplained cause developed cancer without any predominating type of malignancy.