Histologic Clearance of a Giant Cutaneous Squamous Cell Carcinoma with Imiquimod 5% Cream: A Case Report

Cutaneous squamous cell carcinoma (cSCC) is one of the most common skin cancers, with an increasing incidence worldwide. Chronic sun exposure is a major risk factor and lesions are usually observed on sun-exposed areas such as the face, neck, scalp, and hands. Imiquimod cream, an immune response modifier, has shown promising results in the management of selected cases of cSCC.

A 70-year-old, Filipino male presented with 3-year history of a slow growing erythematous plaque on the abdomen. Physical examination revealed a solitary, well-defined, erythematous plaque measuring 5 cm on the left lower quadrant of the abdomen. Histopathologic examination confirmed cSCC. The patient declined surgery and opted for topical treatment with imiquimod 5% cream, applied over 24 weeks for a total of 104 applications. Serial biopsies taken at multiple follow-up points and anatomic sites confirmed complete histologic clearance.

This case highlights one of the few documented instances of histologic cure in a >5 cm cSCC treated solely with imiquimod cream. It underscores the potential of imiquimod as a nonsurgical alternative and expands current treatment for patients who may not be suitable candidates for conventional surgical excision.