title: Preoperative Volume-Based PET Parameter, MTV2.5, as a Potential Surrogate Marker for Tumor Biology and Recurrence in Resected Pancreatic Cancer.
abstract: This study aims to evaluate the role of volume-based positron emission tomography parameters as potential surrogate markers for tumor recurrence in resected pancreatic cancer. Between January 2008 and October 2012, medical records of patients who underwent surgical resection for pancreatic ductal adenocarcinoma and completed ¹⁸F-fluorodeoxyglucose positron emission tomography/CT as a part of preoperative staging work-up were retrospectively reviewed. Not only clinicopathologic variables but also positron emission tomography parameters such as SUVmax, MTV2.5 (metabolic tumor volume), and TLG (total lesion glycolysis) were obtained. Twenty-six patients were women and 31 were men with a mean age of 62.9 ± 9.1 years. All patients were preoperatively determined to resectable pancreatic cancer except 1 case with borderline resectability. R0 resection was achieved in all patients and 45 patients (78.9%) received postoperative adjuvant chemotherapy with or without radiation therapy. Median overall disease-free survival was 12.8 months with a median overall disease-specific survival of 25.1 months. SUVmax did not correlate with radiologic tumor size (P = 0.501); however, MTV2.5 (P = 0.001) and TLG (P = 0.009) were significantly associated with radiologic tumor size. In addition, MTV2.5 (P < 0.001) and TLG (P < 0.001) were significantly correlated with a tumor differentiation. There were no significant differences in TLG and SUVmax according to lymph node ratio; only MTV2.5 was related to lymph node ratio with marginal significance (P = 0.055). In multivariate analysis, lymph node ratio (Exp [β] = 2.425, P = 0.025) and MTV2.5 (Exp[β] = 2.273, P = 0.034) were identified as independent predictors of tumor recurrence following margin-negative resection. Even after tumor size-matched analysis, MTV2.5 was still identified as significant prognostic factor in resected pancreatic cancer (P < 0.05). However, preoperative neoadjuvant treatment attenuated adverse oncologic impact of high preoperative MTV2.5 (P = 0.210). Preoperatively determined volume-based PET parameter, MTV2.5, can potentially be used as a surrogate marker to estimate tumor biology and tumor recurrence. Individual treatment strategies for pancreatic cancer can be suggested based on patients' preoperative MTV2.5.
authors.affiliation: From the Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery (CMK, SHL, HKH, WJL); Nuclear Medicine (MY), Yonsei University College of Medicine; and Pancreaticobiliary Cancer Clinic (CMK, SHL, HKH, MY, WJL), Institute of Gastroenterology, Severance Hospital, Seoul, Korea.
authors.forename: Chang Moo
authors.initials: CM
authors.lastname: Kang
authors.forename: Sung Hwan
authors.initials: SH
authors.lastname: Lee
authors.forename: Ho Kyoung
authors.initials: HK
authors.lastname: Hwang
authors.forename: Mijin
authors.initials: M
authors.lastname: Yun
authors.forename: Woo Jung
authors.initials: WJ
authors.lastname: Lee
mesh_terms: D000368:Aged; D021441:Carcinoma, Pancreatic Ductal / Q000473:pathology / Q000601:surgery; D018572:Disease-Free Survival; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000494:pharmacology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy / Q000379:methods / Q000706:statistics & numerical data; D009364:Neoplasm Recurrence, Local; D009367:Neoplasm Staging; D010180:Pancreatectomy / Q000009:adverse effects / Q000379:methods; D010190:Pancreatic Neoplasms / Q000473:pathology / Q000601:surgery; D049268:Positron-Emission Tomography / Q000379:methods / Q000706:statistics & numerical data; D011237:Predictive Value of Tests; D011300:Preoperative Care / Q000379:methods / Q000706:statistics & numerical data; D011379:Prognosis; D019275:Radiopharmaceuticals / Q000494:pharmacology; D012189:Retrospective Studies; D047368:Tumor Burden
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18