title: Peripheral small-sized (2 cm or less) non-small cell lung cancer with mediastinal lymph node metastasis; clinicopathologic features and patterns of nodal spread.
abstract: OBJECTIVE
  The diagnosis of small-sized (2 cm or less) non-small cell lung cancer (NSCLC) has increased with the development of computed tomography (CT), whereas unexpected extensive multiple-level mediastinal involvement has been occasionally detected in this small-sized lung cancer. To establish the optimal surgical strategy, we retrospectively analyzed the clinicopathologic features, efficacy of preoperative investigations and lobe specific patterns of nodal spread in small-sized NSCLC with mediastinal involvement.
  
  
  METHODS
  Among 1,550 resected lung cancer cases between 1981 and 2000, 267 (17.2%) had peripheral small-sized NSCLC. Of these, 29 patients (10.8%) with mediastinal lymph node involvement who underwent pulmonary resection and systematic nodal dissection were reviewed.
  
  
  RESULTS
  Among 29 patients, 27 patients (93.1%) were adenocarcinoma, and 51.7% (15/29) showed no lymph node enlargement on CT (cN0). Surgical pathology revealed multiple-level mediastinal involvement in 65.5% (19/29) of all patients and 60.0% (9/15) of cN0 patients. All of right upper lobe tumors (n=11) showed multiple-level involvement. Thallium-201 single photon emission computed tomography (201Tl-SPECT) was positive for increased focal uptake in the mediastinum in 72.7% (8/11) of patients.
  
  
  CONCLUSIONS
  The vast majority of cases were adenocarcinoma, and two thirds of them showed multiple-level mediastinal involvement, even in cN0 patients. We thus recommend to perform systematic nodal dissection or meticulous sampling for accurate intrathoracic staging, especially for right upper lobe tumor. 201Tl-SPECT appears to be more sensitive preoperative investigation for mediastinal metastasis compared with CT scan.
authors.affiliation: Kanazawa University School of Medicine, Kanazawa 920-8641, Japan. syuwatan@ncc.go.jp
authors.forename: Shun-ichi
authors.initials: S
authors.lastname: Watanabe
authors.forename: Makoto
authors.initials: M
authors.lastname: Oda
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Tsunezuka
authors.forename: Tetsuhiko
authors.initials: T
authors.lastname: Go
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Ohta
authors.forename: Go
authors.initials: G
authors.lastname: Watanabe
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology / Q000556:secondary / Q000601:surgery; D000328:Adult; D000368:Aged; D002289:Carcinoma, Non-Small-Cell Lung / Q000473:pathology / Q000556:secondary* / Q000601:surgery; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000473:pathology* / Q000601:surgery; D008197:Lymph Node Excision; D008207:Lymphatic Metastasis; D008297:Male; D008482:Mediastinum; D008875:Middle Aged; D009367:Neoplasm Staging; D012189:Retrospective Studies