title: Invasive squamous cell carcinoma after treatment of carcinoma in situ with 5% imiquimod cream.
abstract: Squamous cell carcinoma in situ has the potential to progress to invasive squamous cell carcinoma. This report presents two cases of punch biopsy-proven squamous cell carcinoma in situ, treated with once-daily application of 5% imiquimod cream for 6 weeks. Both patients developed moderate local inflammatory reactions during treatment. The first patient demonstrated clinical clearance of the scalp lesion after treatment. Two months later, he re-presented with a subcutaneous nodule at the same site. Histology was consistent with recurrent squamous cell carcinoma. Five months following excision of the recurrent tumour, he presented with metastatic squamous cell carcinoma to a cervical lymph node. The second patient had low-grade chronic lymphocytic leukaemia and presented with squamous cell carcinoma in situ of the leg that failed to clear clinically after treatment with imiquimod. He presented 4 months later with a focus of invasive squamous cell carcinoma within the lesion.
authors.affiliation: Department of Dermatology, Austin Hospital, Heidelberg, Victoria, Australia. M.Goh@alfred.org.au
authors.forename: Michelle S Y
authors.initials: MS
authors.lastname: Goh
mesh_terms: D000287:Administration, Topical; D000369:Aged, 80 and over; D000634:Aminoquinolines / Q000008:administration & dosage*; D000970:Antineoplastic Agents / Q000008:administration & dosage*; D002278:Carcinoma in Situ / Q000175:diagnosis / Q000188:drug therapy*; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis / Q000188:drug therapy* / Q000601:surgery; D018450:Disease Progression; D006258:Head and Neck Neoplasms / Q000175:diagnosis / Q000188:drug therapy / Q000601:surgery; D006801:Humans; D000077271:Imiquimod; D007866:Leg; D008197:Lymph Node Excision; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D016609:Neoplasms, Second Primary / Q000175:diagnosis* / Q000601:surgery; D012535:Scalp; D012878:Skin Neoplasms / Q000175:diagnosis / Q000188:drug therapy* / Q000601:surgery; D016896:Treatment Outcome
chemical_list: D000634:Aminoquinolines; D000970:Antineoplastic Agents; D000077271:Imiquimod