Peripheral neuropathies in cancer patients may be caused by compression due to tumor invasion, by radiation injury, or by chemotherapy. Plexopathy may also be caused by non-oncologic conditions such as diabetes mellitus, trauma, and aneurysms, thus adding to the diagnostic difficulty. The most common iatrogenic neuropathies are those caused by vincristine and cisplatin. Vincristine, while causing the least myelosuppression of all the vinca alkaloids, is the most neurotoxic. Cisplatin neuropathy often limits the use of this agent, even in patients whose tumors are responsive to it. Part 1 of this article appeared in January.