Quantitative sensory testing was used to assess the prevalence of sensory dysfunction in patients with cancer, carefully screened for other risk factors for neuropathy. Large fibre type sensory function was evaluated using vibration threshold (VT) determinations while small fibre type sensory function was assessed by thermal threshold (TT) determinations. Mean VT and TT were significantly elevated in the toes but not the fingers of cancer patients. VT elevations in the toes occurred in 31% of cancer patients and in 6% of control subjects. TT elevations in the toes occurred in 43% of cancer patients and 4% of control subjects. Based on these findings it is concluded that large and small fibre type sensory dysfunction is much more common in carefully screened cancer patients than in control subjects. This sensory dysfunction is most likely to represent a neuropathy related directly or indirectly associated with cancer.