title: The clinical application value of PET/CT in adenocarcinoma with bronchioloalveolar carcinoma features.
abstract: OBJECTIVE
  The goal of our study was to demonstrate the clinical usefulness of positron emission tomography/computed tomography (PET/CT) for adenocarcinoma with bronchioloalveolar carcinoma (BAC) features, through evaluating the relationship between the intrathoracic lymph node metastases and maximum standardized uptake value (SUVmax), tumor size of the primary tumor and the ratio of BAC component and analysing the correlation of SUVmax, tumor size and the ratio of BAC component.
  
  
  METHODS
  This was a retrospective study. Forty-five patients with focal peripheral lung adenocarcinoma with BAC features were included in this study and underwent the PET/CT scan. Twenty-one patients were women and 24 were men. None of the patients had insulin-dependent diabetes and the serum glucose levels in all patients just before (18)F-FDG was injected were less than 120 mg/dl. The diagnosis of the lesion was made by surgical histopathology.
  
  
  RESULTS
  All patients underwent successful surgery, and pathologic examination confirmed that 34 of 118 excised nodal groups in 18 patients were proved to be positive for malignancy. Univariate analysis revealed 3 potential factors related to intrathoracic lymph node metastases: SUVmax (P = 0.002); the ratio of BAC component (P = 0.002); maximum dimension of a tumor on mediastinal window setting images (mDmax, P = 0.025). The maximum dimension of a tumor on pulmonary window setting images (pDmax, P = 0.373) had no significance. A receiver operating characteristic (ROC) curve based on SUVmax, mDmax and the ratio of BAC component was constructed, the area under curve (AUC) was 85.2, 70.3 and 81.5% separately. There was no statistical significance between AUC of SUVmax and AUC of the ratio of BAC component (Z = 0.901, P = 0.368). The AUC of SUVmax and AUC of the ratio of BAC component were significantly higher than AUC of mDmax (Z = 2.112, P = 0.035; Z = 2.016, P = 0.042).The SUVmax and the ratio of BAC component had significant inverse correlation (r = -0.85, P < 0.01). The mDmax and the ratio of BAC component had significant inverse correlation (r = -0.69, P < 0.01). The SUVmax and mDmax had significant correlation (r = 0.60, P < 0.01).
  
  
  CONCLUSIONS
  PET/CT would be clinically useful for adenocarcinoma with BAC features, because SUVmax obtained by PET/CT can predict the incidence of intrathoracic lymph node metastases at preoperative stages and even for inoperable patients.
authors.affiliation: Department of PET/CT Center, Provincial Hospital, Shandong University, Jinan, People's Republic of China.
authors.forename: Songtao
authors.initials: S
authors.lastname: Liu
authors.forename: Hongxia
authors.initials: H
authors.lastname: Cheng
authors.forename: Shuzhan
authors.initials: S
authors.lastname: Yao
authors.forename: Caixia
authors.initials: C
authors.lastname: Wang
authors.forename: Guangxiu
authors.initials: G
authors.lastname: Han
authors.forename: Xin
authors.initials: X
authors.lastname: Li
authors.forename: Cheng
authors.initials: C
authors.lastname: Liu
mesh_terms: D000230:Adenocarcinoma / Q000150:complications* / Q000175:diagnosis* / Q000473:pathology; D002282:Adenocarcinoma, Bronchiolo-Alveolar / Q000150:complications*; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D012372:ROC Curve; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D047368:Tumor Burden