DESCRIPTION (provided by applicant): Due to major advances in early detection and therapy, an estimated 12 million cancer survivors are living in the United States today. Unfortunately, most cancer therapies are known to carry a substantial risk of adverse long-term effects. One of the most common and debilitating adverse effects is chemotherapy-induced peripheral neuropathy (CIPN), which is associated with many widely used anticancer drugs. The optimal treatment for persistent CIPN remains unknown. Symptomatic treatments include antidepressants, anticonvulsants, non-narcotic and narcotic analgesics. While antidepressants have shown moderate benefit, their use has been limited due to side effects and significant drug to drug interactions. A few small unblinded studies of topical menthol suggest a possible benefit in relieving neuropathy. We hypothesize that six week treatment with 2% topical Menthol application twice a day will decrease persistent neuropathic pain following adjuvant chemotherapy with a Taxane or Oxaliplatin-based regimen. We plan to test this hypothesis with a two arm double blind, placebo controlled, randomized pilot study following adjuvant therapy in breast and colon cancer patients. Our aims are (1) To assess whether six week treatment with twice daily topical Menthol application will decrease persistent neuropathic pain; (2) To evaluate the effect of topical Menthol compared to placebo on global measures of neuropathy; (3) To evaluate the effect of topical Menthol on objective sensory and motor functional tests; and (4) To perform an exploratory analysis evaluating the interaction between treatment and chemotherapy type. To date, we have not been successful at treating or preventing CIPN. This study evaluates the use of a promising and readily available, low cost and well tolerated topical intervention. If found beneficial, this treatment addressing the putative underlying mechanism of CIPN, may bring us one step closer to improving the lives of cancer survivors.