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[A clinicopathologic study on membranous basal cell adenoma].

OBJECTIVE
To investigate the clinicopathologic features and behaviour of membranous basal cell adenoma.


METHODS
Twelve cases with membranous basal cell adenoma of salivary gland were analysed clinicopathologically.


RESULTS
The tumors were composed of epithelial islands of various sizes and shapes. Its histologic finding was characterized by palisading of peripheral cells and excessive hyaline basal membrane. Four cases had co-existing dermal cylindromas of the scalp. In 8 cases, the tumors demonstrated multiple origin. One case showed malignant transformation and cervical lymph node metastasis.


CONCLUSIONS
The differential diagnosis involved the solid variant of basal cell adenoma, basal cell adenocarcinoma, solid subtype of adenoid cystic carcinoma and basal squamous cell carcinoma. Total parotidectomy rather than superficial parotidectomy is suggested to avoid the recurrence of the tumor. A close follow up after treatment is necessary.