Crusted Plaque in the Umbilicus

The use of dermoscopy has been advocated as an adjuvant tool in delineating benign and malignant umbilical lesions when an atypical polymorphous vascular pattern indicating neovascularization has been observed with neoplastic growth.⁵ Once a suspicious umbilical lesion is identified, the first step should be to obtain a skin biopsy or to use fine needle aspiration for cytology.⁶ Biopsy is especially relevant in the background of cancer history because SMJN may present with cancer recurrence.3 Once one of these is obtained, histological and immunohistochemical analysis will guide further workup and diagnosis of the umbilical lesion.

The importance of reviewing such cases lies in the variable presentation of cutaneous metastases such as SMJN and the grim prognosis that accompanies this finding. It presents as a firm indurated plaque or nodule that may present with systemic symptoms suggestive of malignancy, though in 30% of cases it is the sole initial sign.⁷ The nodule may be painful if ulcerated or fissured. Bloody, serous, or purulent discharge may be present. After diagnosis of an SMJN, most patients succumb to the disease within 12 months. Thus, it is vital for dermatologists to investigate umbilical lesions with great caution and a high index of suspicion.