title: Utility of FDG-PET in clinical neuroendocrine prostate cancer.
abstract: BACKGROUND
  Fluorodeoxyglucose (FDG) positron emission tomography (PET) has well-characterized limitations in prostate adenocarcinoma (PCA). However, data assessing the utility of PET in neuroendocrine prostate cancer (NEPC) is limited to isolated case reports. Herein, we describe the first case series to assess the utility of FDG-PET in NEPC.
  
  
  METHODS
  Inclusion criteria consisted of clinically progressive metastatic PCA in the setting of a chromogranin-A levels >1.5× the upper limit of normal, and ≥1 FDG-PET scan after the diagnosis of NEPC, which yielded 23 patients. All metastatic lesions on CT, PET, and bone scan were read by two independent physicians.
  
  
  RESULTS
  Five hundred ninety two unique lesions were identified across all imaging modalities, 510 were bone metastases, and 82 were soft tissue metastases. Of bone lesions, 22.2%, 92.7%, and 77.6% were detected by PET, CT, and bone scan, respectively. Of soft tissue lesions, 95.1% and 97.5% were detected by PET and CT, respectively. Stratified by the median survival from NEPC diagnosis, patients who survived <2.2 versus ≥2.2 years had more PET avid bone (8 vs. 2, P = 0.06) and soft tissue lesions (7 vs. 1, P = 0.01), and higher average SUVmax of bone (5.49 vs. 3.40, P = 0.04) and soft tissue lesions (8.02 vs. 3.90, P = 0.0002).
  
  
  CONCLUSIONS
  In patients with clinical NEPC, we demonstrate that FDG-PET has clinical utility in the detection of metastatic disease. In addition to detection, PET allows for treatment response to determine tumor viability. With novel therapies on the horizon to treat NEPC, consideration to investigate the use of FDG-PET to monitor response is warranted.
authors.affiliation: Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York.
authors.forename: Daniel E
authors.initials: DE
authors.lastname: Spratt
authors.forename: Somali
authors.initials: S
authors.lastname: Gavane
authors.forename: Lisa
authors.initials: L
authors.lastname: Tarlinton
authors.forename: Shoaib B
authors.initials: SB
authors.lastname: Fareedy
authors.forename: Michael G
authors.initials: MG
authors.lastname: Doran
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Zelefsky
authors.forename: Joseph R
authors.initials: JR
authors.lastname: Osborne
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000473:pathology; D000368:Aged; D000369:Aged, 80 and over; D001859:Bone Neoplasms / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000556:secondary; D018450:Disease Progression; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D008875:Middle Aged; D018358:Neuroendocrine Tumors / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology*; D049268:Positron-Emission Tomography / Q000379:methods*; D015995:Prevalence; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology*; D012189:Retrospective Studies; D012983:Soft Tissue Neoplasms / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000556:secondary
chemical_list: D019788:Fluorodeoxyglucose F18
keywords: FDG; PET; neuroendocrine; prostate cancer