Early cutaneous metastasis of adenoid cystic carcinoma of the salivary gland.

Adenoid cystic carcinoma (ACC) of the salivary glands is a malignant tumor characterized by slow but relentless progression that is plagued by local recurrence, late metastases, and ultimately fatal outcomes. Twenty-four percent to 52% of ACCs of the salivary glands result in distant metastasis, primarily involving the lungs, bones, liver, and brain. Cutaneous metastasis of these tumors is rare and usually represents an advanced stage of disseminated disease. We report the case of a 61-year-old man with a history of ACC of the right submandibular region who was referred to our dermatology clinic 2 months following wide excision of the tumor. A nonspecific dermatitis had developed at the surgical site. A skin biopsy was performed due to the discovery of eruptive papules on the scalp and neck, which demonstrated the characteristic histopathologic features of metastatic ACC. Our case underscores the importance of conducting a complete skin examination in oncologic patients, especially focusing on cutaneous and subcutaneous nodules and papules that are eruptive or show rapid development.