Peripheral neuropathy exacerbation associated with topical 5-fluorouracil.
Peripheral neuropathy secondary to 5-flourouracil and capecitabine (Xeloda) has been reported. We report the first case of exacerbation of peripheral neuropathy related to topical 5-flourouracil (Efudex). A 70-year-old Caucasian male with a history of actinic keratosis for 15 years was treated intermittently with topical application of 5-flourouracil. He also developed sensory peripheral neuropathy around the same time, but extensive work-up disclosed no clear etiology. In early 2005, he developed an exacerbation of his peripheral neuropathy following a 21-day course of topical 5-flourouracil for actinic keratosis, especially pain and parasthesias. Dihydropyrimidine dehydrogenase activity was evaluated in the peripheral mononuclear cells both by radioassay and by [2-C] uracil breath test. Dihydropyrimidine dehydrogenase activity was within the normal range by both methods. Stopping topical 5-flourouracil resolved the symptoms to baseline. Instead of topical 5-flourouracil, topical imiquimod was used which did not exacerbate his neuropathy. He was not re-challenged with topical 5-flourouracil. Topical 5-flourouracil has been known to cause mainly dermatological adverse effects, but systemic effects because of absorption are possible, especially in dihydropyrimidine dehydrogenase-deficient patients. As our patient had no other cause responsible for his neuropathy, the onset of symptoms coincided historically with topical application of 5-flourouracil and the 5-flourouracil usage preceded an exacerbation of sensory symptoms, we conclude that this drug was responsible for his polyneuropathy.
Saif
Muhammad Wasif
MW
Section of Medical Oncology, Yale Cancer Center, Yale University School of Medicine, New Haven, Connecticut 06520, USA. wasif.saif@yale.edu
Hashmi
Shahrukh
S
Mattison
Lori
L
Donovan
William B
WB
Diasio
Robert B
RB
D000368:Aged; D000964:Antimetabolites, Antineoplastic / Q000009:adverse effects*; D054067:Dihydropyrimidine Dehydrogenase Deficiency; D042943:Dihydrouracil Dehydrogenase (NADP) / Q000378:metabolism; D005472:Fluorouracil / Q000008:administration & dosage / Q000009:adverse effects*; D006801:Humans; D008297:Male; D010523:Peripheral Nervous System Diseases / Q000139:chemically induced*
D000964:Antimetabolites, Antineoplastic; D042943:Dihydrouracil Dehydrogenase (NADP); D005472:Fluorouracil