Christophe Cassinotto MD, Presenter: Nothing to Disclose

Jean-Pierre Lafourcade, Abstract Co-Author: Nothing to Disclose

Amaury Mouries, Abstract Co-Author: Nothing to Disclose

Bruno Lapuyade, Abstract Co-Author: Nothing to Disclose

Eric Terrebonne, Abstract Co-Author: Nothing to Disclose

Herve Trillaud MD, Abstract Co-Author: Nothing to Disclose

genevieve belleannee, Abstract Co-Author: Nothing to Disclose

Laurence Chiche MD, Abstract Co-Author: Nothing to Disclose

christophe laurent, Abstract Co-Author: Nothing to Disclose

Michel Montaudon MD, Abstract Co-Author: Nothing to Disclose

To prospectively evaluate the ability of CT scan to determine tumor response and predict resectability after neo-adjuvant chemo-radiotherapy (CRT) in patients with non-metastatic locally-advanced pancreatic cancer (LAPC).

This study received ethics approval, and all participants provided written informed consent. We prospectively enrolled consecutive patients with cephalic LAPC who underwent surgical exploration and/or resection following neoadjuvant CRT from June 2009 to May 2013. Two radiologists independently analyzed the baseline and post-CRT CT scans recording the size, attenuation, and circumferential vascular contacts of the tumor. Associations between the post-operative histological grade of tumor response (pTNM) and the clinical, biological and CT scan criteria were assessed using Spearman’s correlation coefficients. CT scan criteria related with the presence of R0 resection were assessed using logistic regression.

Forty-seven patients were included, 33 with R0 resection, and 14 with R1 or no resection. Variables demonstrating a significant correlation with the histological tumor classification of tumor response were: post-CRT CA19-9 level (r=0.46), post-CRT tumor largest axis (r=0.44), post-CRT largest+small axis (r=0.46), change in largest axis (r=0.31), change in largest+small axis (r=0.39), change in SMV/Portal vein contact (r=-0.38), and post-CRT SMA contact (r=0.34). Partial regression of tumor contact with the SMV/Portal vein was associated in all cases with R0 resection (10/10 patients, PPV = 100%), and partial regression of tumor contact with any peripancreatic vascular axis was associated with R0 resection in 91% of cases (20/22 patients, PPV = 91%). Persistence of SMV/Portal vein stenosis after CRT was not predictive for R1 resection.

Partial regression of tumor-vessel contact indicates suitability for surgical exploration, irrespective of the degree of decrease in tumor size or the degree of residual vascular involvement.

CT criteria based on the degree of tumor to vessel contact could provide valuable assistance in making decisions about therapy after completion of neo-adjuvant chemo-radiotherapy.

Cassinotto, C, Lafourcade, J, Mouries, A, Lapuyade, B, Terrebonne, E, Trillaud, H, belleannee, g, Chiche, L, laurent, c, Montaudon, M, Locally-advanced Pancreatic Adenocarcinoma: Reassessment of Response with CT Scan after Neoadjuvant Chemoradiotherapy.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14009226.html