Eruptive epidermoid cysts resulting from treatment with imiquimod.
BACKGROUND
Because of its unique mechanism of action and safety profile, imiquimod, a topical immune response modifier, is used for many benign and malignant dermatologic conditions. Adverse effects are typically limited to treatment site erythema and erosion.


OBJECTIVE
To describe a newly recognized adverse effect of imiquimod.


METHODS
A 79-year-old woman being treated with imiquimod 5 days per week for a nodular basal cell developed a verrucous plaque over the treatment area after 7 weeks of therapy.


RESULTS
Scouting biopsies demonstrated multiple comedones and ruptured epidermoid cysts. There was no evidence of residual basal cell carcinoma.


CONCLUSIONS
Imiquimod is a new and novel treatment option for cutaneous malignancies. We report its successful use in the treatment of a nodular basal cell carcinoma. The multiple comedones and ruptured epidermoid cysts are newly reported adverse effects of imiquimod therapy.
Marty
Chelsy L
CL
Department of Dermatology, Mayo Clinic, Jacksonville, FL 32224, USA.
Randle
Henry W
HW
Walsh
John S
JS
D000287:Administration, Topical; D000368:Aged; D000634:Aminoquinolines / Q000008:administration & dosage / Q000009:adverse effects*; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000009:adverse effects*; D002280:Basal Cell Carcinoma / Q000188:drug therapy*; D003879:Dermatologic Agents / Q000008:administration & dosage; D005260:Female; D006801:Humans; D000077271:Imiquimod; D012176:Retinoids / Q000008:administration & dosage; D012871:Skin Diseases / Q000188:drug therapy / Q000209:etiology*; D012878:Skin Neoplasms / Q000188:drug therapy*; D016896:Treatment Outcome
D000634:Aminoquinolines; D000970:Antineoplastic Agents; D003879:Dermatologic Agents; D012176:Retinoids; D000077271:Imiquimod