Lung tumours with neuroendocrine differentiation

Abstract

Neuroendocrine (NE) tumours of the lung include the low grade typical carcinoid (TC), intermediate grade atypical carcinoid (AC) and the high grade large cell NE carcinoma (LCNEC) and small cell carcinoma (SCLC) (Table 1). NE tumours of the lung comprise approximately 20–25% of all invasive lung malignancies. The most common NE lung tumour is SCLC, which accounts for 15–20% [ 1 Travis WD Travis LB Devesa SS Lung cancer. Cancer. 1995; 75 (Erratum:): 191-202Cancer. 1995; 75 (Erratum:): 2979 Crossref PubMed Google Scholar ], followed by LCNEC, which is about 3% in surgical series, and carcinoid, which accounts for 1–2% of lung cancers. The rarest NE lung tumour is atypical carcinoid which comprises approximately 10% of all lung carcinoids, accounting for approximately 0.1–0.2% of invasive lung cancers [ 2 Chen LC Travis WD Krug LM Pulmonary neuroendocrine tumors: What (little) do we know?. J Natl Compr Cancer Netw. 2006; 4: 623-630 Crossref PubMed Google Scholar ]. These tumours have certain morphologic, ultrastructural, immunohistochemical and molecular characteristics in common [ 3 Gosney JR Pulmonary endocrine pathology. Butterworth-Heinemann, Oxford; Boston1992 Google Scholar , 4 Thunnissen FB Van Eijk J Baak JP et al. Bronchopulmonary carcinoids and regional lymph node metastases. A quantitative pathologic investigation. Am J Pathol. 1988; 132: 119-122 PubMed Google Scholar , 5 Jones DJ Hasleton PS Moore M DNA ploidy in bronchopulmonary carcinoid tumours. Thorax. 1988; 43: 195-199 Crossref PubMed Google Scholar , 6 Rusch VW Klimstra DS Venkatraman ES Molecular markers help characterize neuroendocrine lung tumors. Ann Thorac Surg. 1996; 62: 798-809 Abstract Full Text Full Text PDF PubMed Scopus (78) Google Scholar , 7 Brambilla E Negoescu A Gazzeri S et al. Apoptosis-related factors p53, Bcl2, and Bax in neuroendocrine lung tumors. Am J Pathol. 1996; 149: 1941-1952 PubMed Google Scholar ], but there are important differences in incidence, clinical, epidemiologic, histological, survival, and molecular characteristics [ 8 Travis WD Brambilla E Müller-Hermelink HK Harris CC Pathology and Genetics: Tumours of the Lung, Pleura, Thymus and Heart. IARC, Lyon2004 Google Scholar ]. Diffuse idiopathic NE cell hyperplasia (DIPNECH) is a pre-invasive lesion for carcinoid tumors, but it is very rare. Table 1The spectrum of neuroendocrine (NE) proliferations and neoplasms † Modified from reference [8]. (I)NE cell hyperplasia and tumourlets (A)NE cell hyperplasia 1.NE cell hyperplasia associated with fibrosis and/or inflammation 2.NE cell hyperplasia adjacent to carcinoid tumours 3.Diffuse idiopathic NE cell hyperplasia with or without airway fibrosis/obstruction (B)Tumourlets (less than 0.5 cm) (II)Tumours with NE Morphology (A)Typical carcinoid (0.5 cm or larger) (B)Atypical carcinoid (C)Large cell NE carcinoma Combined large cell NE carcinoma ‡ The histological type of the other component of non-small cell carcinoma should be specified. (D)Small cell carcinoma Combined small cell carcinoma ‡ The histological type of the other component of non-small cell carcinoma should be specified. (II)Non-small cell carcinomas with NE differentiation (NED) (IV)Other tumours with NE properties (A)Pulmonary blastoma (B)Primitive neuroectodermal tumour (C)Desmoplastic round cell tumour (D)Carcinomas with rhabdoid phenotype (E)Paraganglioma † Modified from reference [ 8 Travis WD Brambilla E Müller-Hermelink HK Harris CC Pathology and Genetics: Tumours of the Lung, Pleura, Thymus and Heart. IARC, Lyon2004 Google Scholar ]. ‡ The histological type of the other component of non-small cell carcinoma should be specified. Open table in a new tab