title: Risk Factors for Predicting Occult Lymph Node Metastasis in Patients with Clinical Stage I Non-small Cell Lung Cancer Staged by Integrated Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography.
abstract: Lymph nodes in patients with non-small cell lung cancer (NSCLC) are often staged using integrated 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT). However, this modality has limited ability to detect micrometastases. We aimed to define risk factors for occult lymph node metastasis in patients with clinical stage I NSCLC diagnosed by preoperative integrated FDG-PET/CT.
  
  
  
  We retrospectively reviewed the records of 246 patients diagnosed with clinical stage I NSCLC based on integrated FDG-PET/CT between April 2007 and May 2015. All patients were treated by complete surgical resection. The prevalence of occult lymph node metastasis in patients with clinical stage I NSCLC was analysed according to clinicopathological factors. Risk factors for occult lymph node metastasis were defined using univariate and multivariate analyses.
  
  
  
  Occult lymph node metastasis was detected in 31 patients (12.6 %). Univariate analysis revealed CEA (P = 0.04), SUVmaxof the primary tumour (P = 0.031), adenocarcinoma (P = 0.023), tumour size (P = 0.002) and pleural invasion (P = 0.046) as significant predictors of occult lymph node metastasis. Multivariate analysis selected SUVmaxof the primary tumour (P = 0.049), adenocarcinoma (P = 0.003) and tumour size (P = 0.019) as independent predictors of occult lymph node metastasis.
  
  
  
  The SUVmaxof the primary tumour, adenocarcinoma and tumour size were risk factors for occult lymph node metastasis in patients with NSCLC diagnosed as clinical stage I by preoperative integrated FDG-PET/CT. These findings would be helpful in selecting candidates for mediastinoscopy or endobronchial ultrasound-guided transbronchial needle aspiration.
authors.affiliation: Department of Thoracic Surgery, Sagamihara Kyodo Hospital, 2-8-18 Hashimoto, Midori-ku, Sagamihara, Kanagawa, 252-5188, Japan. kaseda@wb4.so-net.ne.jp.
authors.forename: Kaoru
authors.initials: K
authors.lastname: Kaseda
authors.affiliation: Department of Thoracic Surgery, Sagamihara Kyodo Hospital, 2-8-18 Hashimoto, Midori-ku, Sagamihara, Kanagawa, 252-5188, Japan.
authors.forename: Keisuke
authors.initials: K
authors.lastname: Asakura
authors.affiliation: Department of Pathology, Sagamihara Kyodo Hospital, Kanagawa, Japan.
authors.forename: Akio
authors.initials: A
authors.lastname: Kazama
authors.affiliation: Yuai Clinic, Kanagawa, Japan.
authors.forename: Yukihiko
authors.initials: Y
authors.lastname: Ozawa
mesh_terms: D000230:Adenocarcinoma / Q000000981:diagnostic imaging* / Q000556:secondary* / Q000601:surgery; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002272:Carcinoembryonic Antigen / Q000097:blood; D002289:Carcinoma, Non-Small-Cell Lung / Q000000981:diagnostic imaging* / Q000556:secondary* / Q000601:surgery; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000601:surgery; D008198:Lymph Nodes / Q000473:pathology; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D010994:Pleura / Q000473:pathology; D000072078:Positron Emission Tomography Computed Tomography; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D012307:Risk Factors; D047368:Tumor Burden
chemical_list: D002272:Carcinoembryonic Antigen; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18