Purpose: Report of a neuroendocrine carcinoma of the caruncle as the first sign of a metastatic lung carcinoma.
Design: Interventional case report.
Methods: Excision of a rapidly growing caruncular tumor in a 76-year-old woman with a history of breast cancer.
Results: Pathology revealed a large cell neuroendocrine carcinoma, consistent with metastatic lung carcinoma. Computerized tomography of chest, abdomen, and a bone scan disclosed signs of malignancy in the lungs, liver, and bones, originally considered as metastatic breast cancer. However, this diagnosis was excluded on the basis of histopathological findings and clonality analysis. A primary neuroendocrine (Merkel cell) carcinoma was ruled out on morphologic and immunohistochemical grounds.
Conclusion: We present a unique case of a metastatic large cell neuroendocrine carcinoma of the caruncle.