title: Pulmonary large cell carcinomas with neuroendocrine features are high-grade neuroendocrine tumors.
abstract: BACKGROUND
  In 1999, the World Health Organization (WHO) categorized large cell carcinoma with neuroendocrine features as variants of large cell carcinoma and reclassified neuroendocrine lung tumors, especially typical and atypical carcinoid tumors. However, to date, the clinical relationship between these categories of neuroendocrine lung tumors has not been clearly defined.
  
  
  METHODS
  We analyzed 133 cases of neuroendocrine tumors from primary lung carcinoma cases surgically resected. Using electron microscopy and immunohistochemical staining, we classified these cases as typical carcinoid (TC), atypical carcinoid (AC), large cell carcinoma with neuroendocrine features (LCNF), or small cell lung carcinoma (SCLC) based upon the WHO classification.
  
  
  RESULTS
  TC and AC tumors were not related to smoking (p < 0.001) and, unlike LCNF, were found in younger patients (p < 0.001) without a male predominance (p < 0.001). Multivariate analysis revealed that LCNF predicted poorer overall and disease-free survivals comparable with SCLC (overall survival, p = 0.019, hazards ratio, 6.34; disease-free survival, p = 0.007, hazards ratio, 8.19).
  
  
  CONCLUSIONS
  The prognoses of LCNF are comparable with those of SCLC, and LCNF should be classified as high-grade neuroendocrine tumors.
authors: Department of Thoracic Surgery, Graduate School of Medicine, Chiba University, Japan.
authors: Akira
authors: A
authors: Iyoda
authors: Kenzo
authors: K
authors: Hiroshima
authors: Masayuki
authors: M
authors: Baba
authors: Yukio
authors: Y
authors: Saitoh
authors: Hidemi
authors: H
authors: Ohwada
authors: Takehiko
authors: T
authors: Fujisawa
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018287:Carcinoma, Large Cell / Q000737:chemistry / Q000401:mortality / Q000473:pathology*; D053379:Chromogranin A; D002864:Chromogranins / Q000032:analysis; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008175:Lung Neoplasms / Q000378:metabolism / Q000401:mortality / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D018358:Neuroendocrine Tumors / Q000737:chemistry / Q000401:mortality / Q000473:pathology*; D016708:Synaptophysin / Q000032:analysis
chemical_list: D053379:Chromogranin A; D002864:Chromogranins; D016708:Synaptophysin