Photosensitivity due to a fluorouracil derivative.

Area of Science:

• Dermatology
• Photobiology
• Oncology

Background:

• Chemotherapy agents, such as 1-(2-tetrahydrofuryl)-5-fluorouracil, can cause cutaneous adverse reactions.
• Photosensitivity is a known side effect of some medications, but the specific mechanisms can vary.

Observation:

• A patient undergoing chemotherapy developed a lichen planus-like eruption.
• The eruption was triggered by exposure to long-wave ultraviolet light (UV-A).
• The photosensitivity reaction was reproducible upon re-exposure to the drug and UV-A.

Findings:

• The action spectrum for the photosensitivity was identified as UV-A.
• Photopatch testing with the drug was negative.
• Patients on the same drug without dermatitis did not exhibit UV-A sensitivity.

Implications:

• The findings suggest a possible photoallergic mechanism for the photosensitivity reaction.
• This highlights the importance of considering drug-induced photosensitivity in patients on chemotherapy.
• Further investigation into photoallergic reactions to 1-(2-tetrahydrofuryl)-5-fluorouracil is warranted.