Two cases of large cell neuroendocrine carcinoma of the lung

Abstract

Background: Large cell neuroendocrine carcinoma of the lung (LCNEC) is poorly differentiated lung carcinoma with neuroendocrine features. We encountered two cases of LCNEC and report the cytological findings here.
Cases: Tumor cells were found in bronchial brushing material in cases 1 and 2, and in sputum in case 2. In each case, tumor cells had abundant granular cytoplasm and large irregular shaped nuclei with granular chromatin. Tumor cells showed a partially palisading or rosette-like arrangement.
Conclusion: The cytological and immunohistochemical features of the tumors described above revealed that these tumors had both epithelial and neuroendocrine characters, that is they were LCNEC. In this paper we discuss the diagnostic basis of LCNEC and the strategies for differential diagnosis with small cell carcinoma, atypical carcinoid and large cell carcinoma of the lung.