Eyelid basal cell carcinoma with neuroendocrine differentiation: a case report and literature review.

Basal cell carcinoma (BCC) is the most common type of malignant tumor in the periocular region. BCCs with neuroendocrine differentiation in the periocular region, however, have not been described in the literature.We present a retrospective case review of a patient with an eyelid BCC with neuroendocrine differentiation. Demographical, clinical, radiological, surgical, histological, and follow-up data are presented.The patient presented with a slow-growing lesion of the eyelid with associated epiphora and dull ache. Initial incisional biopsy of the lesion revealed an infiltrating carcinoma composed of epithelial cells. Immunohistochemistry showed that the tumor was positive for p40, Ber-Ep4, neuron specific enolase (NSE), chromogranin A, CD56 (NCAM), and synaptophysin. The pathology from the margin-controlled excision showed basosquamous cell carcinoma with neuroendocrine differentiation. Tumor recurrence was not detected clinically at the post-operative six-month review.BCC with neuroendocrine marker positivity represents an important diagnostic differential for rare eyelid carcinomas such as primary cutaneous neuroendocrine carcinoma and metastatic small cell carcinoma that have a poor prognosis. The prognostic importance of neuroendocrine marker positivity in BCCs is uncertain. The present case provides further evidence for neuroendocrine differentiation in BCCs.