title: Carcinoid tumours: predicting the location of the primary neoplasm based on the sites of metastases.
abstract: OBJECTIVE
  To predict the primary neuroendocrine tumour of the gastrointestinal tract site based on observed metastatic sites.
  
  
  METHODS
  We studied data from the radiology database of a single, large cancer centre on 250 patients with pathologically confirmed neuroendocrine tumours. Primary tumour sites and the locations of metastases were collected from pathologic and radiologic reports of all available imaging modalities, such as computed tomography (CT), positron emission tomography (PET/CT), magnetic resonance imaging (MRI) and octreotide scans in the database. A nominal regression model was used to predict primary tumour site using the observed metastatic sites. Regression coefficients that were not statistically significant at the 5 % level were eliminated from the model in a stepwise procedure.
  
  
  RESULTS
  Lung and liver metastases were not statistically significant predictors of the location of primary tumours (p = 0.86 and 0.074, respectively); whereas, lymph node, bone, and peritoneal metastases were significant predictors (p < 0.0001, 0.0004, and 0.014, respectively).
  
  
  CONCLUSIONS
  Metastatic neuroendocrine tumours to the lymph nodes, bone, and peritoneum can be used to predict the primary neuroendocrine site; however, metastases in the lung and liver alone cannot predict the site of the primary tumour site.
authors.affiliation: Department of Diagnostic Radiology, University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Blvd., Houston, TX 77030, USA. priya.bhosale@mdanderson.org
authors.forename: P
authors.initials: P
authors.lastname: Bhosale
authors.forename: A
authors.initials: A
authors.lastname: Shah
authors.forename: W
authors.initials: W
authors.lastname: Wei
authors.forename: G
authors.initials: G
authors.lastname: Varadhachary
authors.forename: V
authors.initials: V
authors.lastname: Johnson
authors.forename: V
authors.initials: V
authors.lastname: Shah
authors.forename: V
authors.initials: V
authors.lastname: Kundra
mesh_terms: D000328:Adult; D000368:Aged; D002276:Carcinoid Tumor / Q000175:diagnosis* / Q000556:secondary; D015331:Cohort Studies; D016208:Databases, Factual; D003952:Diagnostic Imaging / Q000379:methods*; D005260:Female; D005770:Gastrointestinal Neoplasms / Q000175:diagnosis* / Q000556:secondary; D006801:Humans; D008207:Lymphatic Metastasis / Q000175:diagnosis; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis / Q000175:diagnosis; D009382:Neoplasms, Unknown Primary / Q000175:diagnosis* / Q000473:pathology; D018358:Neuroendocrine Tumors / Q000175:diagnosis / Q000556:secondary; D049268:Positron-Emission Tomography / Q000379:methods; D011237:Predictive Value of Tests; D012044:Regression Analysis; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods