title: CD117 immunoreactivity in high-grade neuroendocrine tumors of the lung: a comparative study of 39 large-cell neuroendocrine carcinomas and 27 surgically resected small-cell carcinomas.
abstract: Little is known about CD117 prevalence and clinicopathological implications in pulmonary large-cell neuroendocrine carcinoma. We studied CD117 immunoreactivity in surgical specimens from 39 large-cell neuroendocrine carcinomas of stages I-III and 27 limited-disease small-cell carcinomas, 56 typical and atypical carcinoids of the lung, and 10 neuroendocrine tumorlets, including the membrane and cytoplasmic immunostaining patterns. Membrane CD117 immunoreactivity in 5% or more tumor cells was documented in 30 (77%) large-cell neuroendocrine carcinomas and 18 (67%) small-cell carcinomas and 4 (7%) carcinoids, whereas cytoplasmic labeling was seen in 17 (44%) large-cell neuroendocrine carcinomas, 19 (70%) small-cell carcinomas, and 3 (5%) carcinoids. None of the neuroendocrine cells of the normal bronchial epithelium and of 10 tumorlets showed any CD117 immunoreactivity. Cytoplasmic immunostaining was more prevalent in small-cell carcinomas, whereas membrane labeling did not differ between the two types of high-grade carcinomas. Downregulation of CD117 by neoadjuvant chemotherapy was seen in large-cell neuroendocrine carcinomas but not small-cell carcinomas. Multiple linear regression analysis demonstrated a marginal association between cytoplasmic CD117 immunoreactivity and regional lymph node metastasis in small-cell carcinomas but not large-cell neuroendocrine carcinomas. There was no association between CD117 immunoreactivity and survival in either small-cell carcinoma or large-cell neuroendocrine carcinoma patients.
authors.affiliation: Division of Pathology and Laboratory Medicine, European Institute of Oncology, Via G. Ripamonti 435, 20141 Milan, Italy. giuseppe.pelosi@ieo.it
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Pelosi
authors.forename: Michele
authors.initials: M
authors.lastname: Masullo
authors.forename: Maria Elena
authors.initials: ME
authors.lastname: Leon
authors.forename: Giulia
authors.initials: G
authors.lastname: Veronesi
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Spaggiari
authors.forename: Felice
authors.initials: F
authors.lastname: Pasini
authors.forename: Angelica
authors.initials: A
authors.lastname: Sonzogni
authors.forename: Antonio
authors.initials: A
authors.lastname: Iannucci
authors.forename: Enrica
authors.initials: E
authors.lastname: Bresaola
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Viale
mesh_terms: D000368:Aged; D018288:Carcinoma, Small Cell / Q000737:chemistry* / Q000401:mortality / Q000473:pathology; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008175:Lung Neoplasms / Q000737:chemistry* / Q000401:mortality / Q000473:pathology; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D018358:Neuroendocrine Tumors / Q000737:chemistry* / Q000401:mortality / Q000473:pathology; D019009:Proto-Oncogene Proteins c-kit / Q000032:analysis*
chemical_list: D019009:Proto-Oncogene Proteins c-kit