Increased tumour ADC value during chemotherapy predicts improved survival in unresectable pancreatic cancer

• Published in: European radiology 2016-06, Vol.26 (6), p.1835-1842
• Main Authors: Nishiofuku, Hideyuki, Tanaka, Toshihiro, Marugami, Nagaaki, Sho, Masayuki, Akahori, Takahiro, Nakajima, Yoshiyuki, Kichikawa, Kimihiko
• Format: Article
• Language: English
• Subjects: Adenocarcinoma - diagnostic imaging; Adenocarcinoma - drug therapy; Adult; Aged; Aged, 80 and over; Antineoplastic Agents - therapeutic use; Diagnostic Radiology; Diffusion Magnetic Resonance Imaging - methods; Female; Humans; Image Interpretation, Computer-Assisted - methods; Imaging; Internal Medicine; Interventional Radiology; Kaplan-Meier Estimate; Male; Medicine; Medicine & Public Health; Middle Aged; Multivariate Analysis; Neuroradiology; Oncology; Pancreatic cancer; Pancreatic Neoplasms - diagnostic imaging; Pancreatic Neoplasms - drug therapy; Prognosis; Proportional Hazards Models; Prospective Studies; Radiology; Regression Analysis; Treatment Outcome; Ultrasound
• ISSN: 0938-7994; 1432-1084
• DOI: 10.1007/s00330-015-3999-2

Objectives To investigate whether changes to the apparent diffusion coefficient (ADC) of primary tumour in the early period after starting chemotherapy can predict progression-free survival (PFS) or overall survival (OS) in patients with unresectable pancreatic adenocarcinoma. Methods Subjects comprised 43 patients with histologically confirmed unresectable pancreatic cancer treated with first-line chemotherapy. Minimum ADC values in primary tumour were measured using the selected area ADC (sADC), which excluded cystic and necrotic areas and vessels, and the whole tumour ADC (wADC), which included whole tumour components. Relative changes in ADC were calculated from baseline to 4 weeks after initiation of chemotherapy. Relationships between ADC and both PFS and OS were modelled by Cox proportional hazards regression. Results Median PFS and OS were 6.1 and 11.0 months, respectively. In multivariate analysis, sADC change was the strongest predictor of PFS (hazard ratio (HR), 4.5; 95 % confidence interval (CI), 1.7–11.9; p = 0.002). Multivariate Cox regression analysis for OS revealed sADC change and CRP as independent predictive markers, with sADC change as the strongest predictive biomarker (HR, 6.7; 95 % CI, 2.7–16.6; p = 0.001). Conclusion Relative changes in sADC could provide a useful imaging biomarker to predict PFS and OS with chemotherapy for unresectable pancreatic adenocarcinoma. Key Points • Relative change in ADC value can predict survival in unresectable pancreatic cancer. • ADC change could determine a chemosensitivity of pancreatic cancer. • ADC values should be measured by excluding cystic, necrotic areas and vessels.