Computed tomographic findings of large cell neuroendocrine carcinoma of the lung.

The purpose of our study was to describe the computed tomography (CT) findings of large cell neuroendocrine carcinoma (LCNEC) and to correlate radiological and pathological findings. We reviewed the CT findings of 36 patients [including the high-resolution computed tomography (HRCT) findings of 29 patients] with resected LCNEC specimens. There were 33 men (92%), and 30 patients had a smoking history (83%). Only one case was of the central type. Mediastinal or hilar lymphadenopathy was seen in 12 (33%), but only one showed bulky lymphadenopathy. The HRCT findings of LCNEC consisted of irregular margins (66%), surrounding emphysema (41%), notching (38%), calcifications (21%), and pleural indentation (24%). Our study indicates that the CT image of LCNEC generally shows a peripherally located, expansively growing, irregularly margined pulmonary mass, with or without calcification, and without bulky lymphadenopathy. While the CT image of LCNEC resembles that of squamous cell carcinoma, cavitation is infrequent. LCNEC cannot be differentiated from poorly differentiated adenocarcinoma or atypical carcinoid on the basis of CT findings.