title: Metabolic Signature on 18F-FDG PET/CT, HER2 Status, and Survival in Gastric Adenocarcinomas.
abstract: The human epidermal growth factor 2 (HER2)-overexpressing (HER2-positive [HER2+]) gastric (GC) and gastroesophageal junction adenocarcinomas (GEJC) are felt to represent a more aggressive form of disease, which may correlate to increased metabolic activity. Whether tumor SUVmaxmeasured by18F-FDG PET/CT could be a preoperative parameter used to predict HER2 status of GC/GEJC is unknown.
  
  
  METHODS
  Pathology reports of HER2+ GC/GEJC biopsies and resections from 31 patients were reviewed and compared with HER2-negative (HER2-) cases distributed evenly over the same time period. We analyzed their SUVmaxintensity and then compared the HER2 status and SUVmaxparameters and their association with survival.
  
  
  RESULTS
  After matching for age and sex, there was no difference in SUVmaxbetween HER2+ and HER2- cases (9.7 and 8.4, respectively; P = 0.6). No difference was seen between HER2+ and HER2- cases in tumor histology (81% and 57% intestinal type, respectively; P = 0.11), size (2.6 and 3.8 cm, respectively; P = 0.12), differentiation (47% and 68% poorly differentiated, respectively; P = 0.06), or presence of lymph node metastasis (60% and 40%, respectively; P = 0.3). Although there was no difference in survival demonstrated by HER2+ and HER2- cases, there was a significant difference in survival between SUVmaxabove (12.2 mo) and below (30 mo) the median SUVmax(6.6, P = 0.01).
  
  
  CONCLUSIONS
  Our study shows that SUVmaxis not associated with HER2 status of GC/GEJC. Independent of HER2 overexpression, patients with a high SUVmaxdemonstrate a worse overall survival, suggesting that metabolic signature is a better predictor of biologic tumor aggressiveness than its histologic signature.
authors: Department of Pathology, Yale School of Medicine, New Haven, Connecticut romulo.celli@yale.edu.
authors: Romulo
authors: R
authors: Celli
authors: Sciences Po, Paris, France; and.
authors: Monica
authors: M
authors: Colunga
authors: Department of Pathology, Yale School of Medicine, New Haven, Connecticut.
authors: Natalie
authors: N
authors: Patel
authors: QMC Quality Medical Consulting, Hamden, Connecticut.
authors: Mehdi
authors: M
authors: Djekidel
authors: Department of Pathology, Yale School of Medicine, New Haven, Connecticut.
authors: Dhanpat
authors: D
authors: Jain
mesh_terms: D000230:Adenocarcinoma / Q000000981:diagnostic imaging* / Q000378:metabolism* / Q000473:pathology; D000368:Aged; D004943:Esophagogastric Junction / Q000000981:diagnostic imaging / Q000473:pathology; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D000072078:Positron Emission Tomography Computed Tomography; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism*; D013274:Stomach Neoplasms / Q000000981:diagnostic imaging* / Q000378:metabolism* / Q000473:pathology; D016019:Survival Analysis
chemical_list: D019788:Fluorodeoxyglucose F18; D018719:Erb-b2 Receptor Tyrosine Kinases; C508053:ERBB2 protein, human
keywords: 18F-FDG PET/CT; HER2; gastric carcinoma; metabolic signature