Abstract
Marjolin ulcer is a rare malignant neoplasm, which develops in chronic ulcers and long-standing skin scars, such as surgical scars. The clinical evolution of Marjolin ulcer is more aggressive with respect to other types of skin cancer or the other etiologies, so its early diagnosis and adequate treatment are key in the pacient's outcome. The case of a 62-year-old male is presented, with a 30-year medial longitudinal sternotomy scar due to anticoagulated mechanical aortic valve replacement, where squamous lesion is observed that was initially diagnosed and treated as granuloma. Due to clinical suspicion, a biopsy is performed that reports a well-differentiated squamous cell carcinoma 0.2 cm deep. We believe that the publication of the case is relevant since it is exceptional according to the reviewed international medical literature, and it is also the first case reported in the country.