Histologic Grading the Extent of Residual Carcinoma Following Neoadjuvant Chemoradiation in Pancreatic Ductal Adenocarcinoma: A Predictor for Patient Outcome
Deyali Chatterjee, Matthew H Katz, Asif Rashid, Gauri R Varadhachary, Robert A Wolff, Hua Wang, Jeffrey E Lee, Peter WT Pisters, Jean-Nicolas Vauthey, Christopher Crane, Henry F Gomez, James L Abbruzzese, Jason B Fleming, Huamin Wang. University of Texas M.D. Anderson Cancer Center, Houston, TX
Background: Several grading schemes for the extent of residual tumor in post-treatment pancreaticoduodenectomy (PD) specimens have been proposed. However, the prognostic significance of these grading schemes is unknown.
Design: Histopathologic slides of 223 cases who received neoadjuvant chemoradiation and PD were reviewed. The extent of residual tumor was graded using both the College of American Pathologists (CAP) and the Evans grading systems. The grading results were correlated with clinicopathological parameters and survival.
Results: Among the 223 patients, 6 patients (2.7%) showed pathologic complete response (pCR, CAP Grade 0 or Evans grade IV), 36 cases (16.1%) with minimal residual tumor (CAP Grade 1 or Evans grade III), 124 cases (55.6%) with moderate response (CAP Grade 2 or Evans grade IIb) and 57 cases (25.6%) with poor response (CAP grade 3, 18 with Evans Grade I and 39 with Evans Grade IIa response). Patients with pCR or minimal residual tumor (response group 1) had better survivals than those with moderate and poor response (response group 2). Response group 1 patients had lower post-therapy tumor and AJCC stages and lower rates of lymph node metastasis and positive resection margin. Grading the extent of residual tumor is an independent prognostic factor for OS in multivariate analysis.
Conclusions: pCR or minimal residual tumor in post-treatment PD specimens correlate with better survival in patients with PDAC who received neoadjuvant therapy and PD. Histologic grading of the extent of residual tumor in PD specimen is an important prognostic factor in patients with PDAC who received neoadjuvant therapies.
Monday, March 19, 2012 8:00 AM
Platform Session: Section G1, Monday Morning