title: Timing of metabolic response monitoring during erlotinib treatment in non-small cell lung cancer.
abstract: The purpose of this study was to prospectively evaluate the timing of metabolic response monitoring with (18)F-FDG PET of (neoadjuvant) erlotinib treatment in patients with early-stage non-small cell lung cancer.
  
  
  METHODS
  This study was designed as an open-label phase II trial performed in 4 hospitals in The Netherlands. Patients received preoperative erlotinib (150 mg) once daily for 3 wk. Response evaluation was performed after 4-7 d and at 3 wk with (18)F-FDG PET/CT scans. Tumor (18)F-FDG uptake and changes were measured as standardized uptake values (SUVs). The metabolic response was classified on the basis of European Organization for Research and Treatment of Cancer criteria (>25% decrease in the maximum SUV) and was compared with histopathologic regression as observed in the resection specimen.
  
  
  RESULTS
  From December 2006 to November 2010, 60 patients with non-small cell lung cancer eligible for surgical resection were enrolled in this study. For 43 patients (18 men and 25 women), baseline (18)F-FDG PET/CT scans as well as both monitoring scans and histopathologic response monitoring were available. A partial metabolic response on (18)F-FDG PET/CT scans was observed for 10 patients (23%) after 1 wk and for 14 patients (33%) after 3 wk. Histopathologic examination revealed regression (necrosis of >50%) in 11 patients (26%). In these patients, the maximum SUV decreased by a mean of 17% within 1 wk and a mean of 31% at 3 wk. Seven patients were identified as responders within 1 wk.
  
  
  CONCLUSIONS
  Response monitoring with (18)F-FDG PET/CT within 1 wk after the start of erlotinib treatment identified approximately 64% of histopathologic responders on the basis of European Organization for Research and Treatment of Cancer criteria.
authors.affiliation: Department of Surgical Oncology, The Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Amsterdam, The Netherlands.
authors.forename: Matthijs H
authors.initials: MH
authors.lastname: van Gool
authors.affiliation: Department of Surgical Oncology, The Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Amsterdam, The Netherlands Department of Nuclear Medicine, The Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Amsterdam, The Netherlands.
authors.forename: Tjeerd S
authors.initials: TS
authors.lastname: Aukema
authors.affiliation: Department of Thoracic Oncology, The Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Amsterdam, The Netherlands.
authors.forename: Eva E
authors.initials: EE
authors.lastname: Schaake
authors.affiliation: Department of Surgery, Kennemer Gasthuis, Haarlem, The Netherlands.
authors.forename: Herman
authors.initials: H
authors.lastname: Rijna
authors.affiliation: Department of Nuclear Medicine, The Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Amsterdam, The Netherlands.
authors.forename: Renato A
authors.initials: RA
authors.lastname: Valdés Olmos
authors.affiliation: Department of Pathology, The Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Amsterdam, The Netherlands; and.
authors.forename: Renée
authors.initials: R
authors.lastname: van Pel
authors.affiliation: Department of Thoracic Oncology, The Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Amsterdam, The Netherlands.
authors.forename: Sjaak A
authors.initials: SA
authors.lastname: Burgers
authors.affiliation: Department of Biometrics, The Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Amsterdam, The Netherlands.
authors.forename: Harm
authors.initials: H
authors.lastname: van Tinteren
authors.forename: Houke M
authors.initials: HM
authors.lastname: Klomp
mesh_terms: D000328:Adult; D000368:Aged; D002289:Carcinoma, Non-Small-Cell Lung / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000378:metabolism*; D000069347:Erlotinib Hydrochloride; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D049268:Positron-Emission Tomography; D011799:Quinazolines / Q000627:therapeutic use*; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D011799:Quinazolines; D019788:Fluorodeoxyglucose F18; D000069347:Erlotinib Hydrochloride
keywords: PET/CT; epidermal growth; molecular biology; non–small cell lung carcinoma; oncology