Horrifying Basal Cell Carcinoma Presenting as Progressive Pyoderma Gangrenosum: Case Report.

INTRODUCTION: Skin ulcers can be challenging to diagnose and manage, particularly with comorbid autoimmune and gastrointestinal diseases. Occam's razor encourages the simplest explanation to guide care, but reconsideration must occur when intervention proves futile.

CASE PRESENTATION: We report the case of a 70-year-old male, with a 17-year history of expanding pretibial skin ulcer, presumed by prior care providers to be pyoderma gangrenosum related to Crohn's disease. A surgical biopsy performed upon presentation to our institution revealed basal cell carcinoma of the skin, invasive to the proximal tibia with associated deep infection, prompting transfemoral amputation.

CONCLUSION: This report is written as a reminder to reconsider a diagnosis and consider seeking additional expertise when a patient's condition progressively worsens despite intervention. Earlier diagnosis likely would have facilitated therapeutic limb salvage care.