Cutaneous Metastasis From Adenoid Cystic Carcinoma of the Parotid Gland

BACKGROUND: Cutaneous metastasis from adenoid cystic carcinoma of the salivary gland is very rare. OBJECTIVE: To present an unusual case of cutaneous metastasis from adenoid cystic carcinoma of the right parotid gland. METHODS: A 63-year-old woman with multiple subcutaneous nodules on the abdomen and a gradually enlarged mass over the right parotid area was examined. A skin biopsy was taken from one of the abdominal nodules. RESULT: Skin biopsy demonstrated the characteristic histopathologic features of metastatic adenoid cystic carcinoma. A subsequent computerized tomography of the head and neck revealed a huge soft tissue mass involving the right parotid gland. Computerized tomography of the chest revealed extensive nodular pleural thickening, and pleural biopsy also showed typical histopathologic features of metastatic adenoid cystic carcinoma. All of these results are consistent with the diagnosis of an adenoid cystic carcinoma of the right parotid gland with disseminated metastases. CONCLUSION: We report a rare case of cutaneous metastasis from adenoid cystic carcinoma of the right parotid gland. The presentation of cutaneous metastasis is often nonspecific and may mimic benign lesions. Subcutaneous nodules that are rapidly developing or eruptive, are rapidly growing and have stony hardness in nature, have pain or tenderness, and have nonhealing ulceration remind us of the possibility of cutaneous metastases. Dermatologists and dermatologic surgeons should keep the diagnosis of cutaneous metastasis in mind and always perform skin biopsy when encountering these lesions.