Differential diagnosis of a venous ulcer and basal cell carcinoma. A case series report

Abstract

Chronic ulcers in the lower extremities pose a significant clinical challenge, with venous ulcers being the most prevalent. However, differential diagnosis with other etiologies—arterial, neuropathic, mixed, vasculitic, or neoplastic—is essential. Among the latter, malignant ulcers are uncommon but clinically relevant, especially in lesions with a slow progression.
We present three cases of women, approximately 80 years of age, with chronic ulcers in the lower extremities, initially diagnosed as venous. All shared clinical features suggestive of venous insufficiency and had received unsuccessful compression therapy. Due to the lack of therapeutic response, biopsies were performed, which revealed a diagnosis of basal cell carcinoma  in all three cases.
The appearance of basal cell carcinomas in venous ulcers is rare, with squamous cell carcinoma being the most frequently described type of ulcer in these cases. The clinical course of the lesions, the histology, and the evidence reviewed suggest two possible mechanisms: secondary malignancy due to chronic inflammation or primary basal cell carcinoma with ulcerated presentation. The evidence supports the need to suspect malignancy in chronic lesions with irregular borders, purplish coloration, or friable tissue. Early biopsy is crucial to avoid diagnostic delays and optimize treatment.
Venous ulcers with a slow progression that do not respond to conventional treatment should be re-evaluated by biopsy, especially if they present atypical signs. Although basal cell carcinoma is rare, early detection allows for effective treatment, reducing complications. Continuous clinical surveillance and a rigorous diagnostic approach are essential to improve the prognosis in these patients.