Giant ulcerating squamous cell carcinoma arising from linear porokeratosis: a case study.

Linear porokeratosis is one of the infrequent variants of porokeratosis, a rare disorder of keratinization that may develop into several epidermal malignancies, among them squamous cell carcinoma. Clinical surveillance for malignancy is imperative, but in cases when large or many lesions are present, surgical removal of porokeratosis lesions would result in an unfavorable amount of scarring. A case of a large, nonhealing full-thickness ulcer caused by a giant ulcerating squamous cell carcinoma occurring within lesions of long-standing linear porokeratosis is reported in a 43-year-old woman with a recent diagnosis of ulcerative colitis (UC). Wide excision of the ulcer and plastic surgical reconstruction of the area were performed. PET scans did not show metastases, so her prognosis is good based on definitive excision of the tumor. Physicians should be aware of this cutaneous disease and the importance of annual follow-up for these patients to monitor for any lesion that exhibits clinical features concerning for malignancy.