"Ecdysis" secondary to 5-fluorouracil

Area of Science:

• Dermatology
• Oncology
• Pathology

Background:

• Basal cell carcinoma (BCC) is the most common type of skin cancer.
• 5-fluorouracil (5-FU) is a topical chemotherapeutic agent used for treating certain skin cancers.
• Standard treatment protocols for BCC may involve surgical excision, Mohs surgery, or topical therapies.

Observation:

• Three patients with basal cell carcinoma were treated with 5-fluorouracil.
• A distinctive necrotic reaction was observed following treatment.
• This necrosis could be completely "shelled out" like a snake skin upon curettage.

Findings:

• The observed phenomenon was termed "ecdysis."
• Histologic examination of the necrotic tissue revealed tumor necrosis, leukocytes, and fibrin.
• No tumor recurrences were observed in the patients during the follow-up period.

Implications:

• "Ecdysis" may represent a unique response to 5-fluorouracil in basal cell carcinoma.
• This finding could offer new insights into the mechanism of action of topical chemotherapy.
• Further research is warranted to understand the prevalence and significance of ecdysis in BCC treatment.