title: The IASLC Lung Cancer Staging Project: Background Data and Proposals for the Classification of Lung Cancer with Separate Tumor Nodules in the Forthcoming Eighth Edition of the TNM Classification for Lung Cancer.
abstract: Separate tumor nodules with the same histologic appearance occur in the lungs in a small proportion of patients with primary lung cancer. This article addresses how such tumors can be classified to inform the eighth edition of the anatomic classification of lung cancer. Separate tumor nodules should be distinguished from second primary lung cancer, multifocal ground glass/lepidic tumors, and pneumonic-type lung cancer, which are addressed in separate analyses.
  
  
  
  Survival of patients with separate tumor nodules in the International Association for the Study of Lung Cancer database were analyzed. This was compared with a systematic literature review.
  
  
  
  Survival of clinically staged patients decreased according to the location of the separate tumor nodule relative to the index tumor (same lobe > same side > other side) in N0 and N-any cohorts (all M0 except possible other-side nodules). However, there was also a decrease in the proportion of patients resected; among only surgically resected or among nonresected patients no survival differences were noted. There were no survival differences between patients with same-lobe nodules and those with other T3 tumors, between patients with same-side nodules and those with T4 tumors, and patients with other-side nodules and those with other M1a tumors. The data correlated with those identified in a literature review.
  
  
  
  Tumors with same-lobe separate tumor nodules (with the same histologic appearance) are recommended to be classified as T3, same-side nodules as T4, and other-side nodules as M1a. Thus, there is no recommended change between the seventh and eighth edition of the TNM classification of lung cancer.
authors.affiliation: Department of Surgery, Yale University, New Haven, Connecticut. Electronic address: frank.detterbeck@yale.edu.
authors.forename: Frank C
authors.initials: FC
authors.lastname: Detterbeck
authors.affiliation: Cancer Research And Biostatistics, Seattle, Washington.
authors.forename: Vanessa
authors.initials: V
authors.lastname: Bolejack
authors.affiliation: Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan.
authors.forename: Douglas A
authors.initials: DA
authors.lastname: Arenberg
authors.affiliation: Cancer Research And Biostatistics, Seattle, Washington.
authors.forename: John
authors.initials: J
authors.lastname: Crowley
authors.affiliation: Department of Thoracic Surgery, New York University, New York, New York.
authors.forename: Jessica S
authors.initials: JS
authors.lastname: Donington
authors.affiliation: Department of Pathology, University of Colorado, Denver, Colorado.
authors.forename: Wilbur A
authors.initials: WA
authors.lastname: Franklin
authors.affiliation: Respiratory Medicine Service, Hôpital Louis Pradel, Hospices Civils de Lyon, Lyon, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Girard
authors.affiliation: Department of Diagnostic Imaging, Tel-Aviv University, Ramat Gan, Israel.
authors.forename: Edith M
authors.initials: EM
authors.lastname: Marom
authors.affiliation: Department of Internal Medicine, Cleveland Clinic, Cleveland, Ohio.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Mazzone
authors.affiliation: Department of Histopathology, Royal Brompton and Harefield National Health Service Foundation Trust and Imperial College, London, United Kingdom.
authors.forename: Andrew G
authors.initials: AG
authors.lastname: Nicholson
authors.affiliation: Thoracic Surgery Service, Sloan-Kettering Cancer Center, New York, New York.
authors.forename: Valerie W
authors.initials: VW
authors.lastname: Rusch
authors.affiliation: Department of Internal Medicine, Yale University, New Haven, Connecticut.
authors.forename: Lynn T
authors.initials: LT
authors.lastname: Tanoue
authors.affiliation: Department of Pathology, Sloan-Kettering Cancer Center, New York, New York.
authors.forename: William D
authors.initials: WD
authors.lastname: Travis
authors.affiliation: Division of Thoracic Surgery, Keio University, School of Medicine, Tokyo, Japan.
authors.forename: Hisao
authors.initials: H
authors.lastname: Asamura
authors.affiliation: Thoracic Surgery Service, Hospital Universitari Mutua Terrassa; Centros de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERES) Lung Cancer Group, Terrassa, Barcelona, Spain.
authors.forename: Ramón
authors.initials: R
authors.lastname: Rami-Porta
mesh_terms: D000230:Adenocarcinoma / Q000145:classification* / Q000556:secondary; D006801:Humans; D008175:Lung Neoplasms / Q000145:classification* / Q000473:pathology; D015201:Meta-Analysis as Topic; D009367:Neoplasm Staging / Q000592:standards*; D016609:Neoplasms, Second Primary / Q000145:classification* / Q000473:pathology; D011379:Prognosis; D015996:Survival Rate
keywords: Lung cancer; Lung cancer staging; Multiple tumors; Non–small cell lung cancer; TNM classification