Does Size Matter in Pancreatic Cancer?

Abstract

Among the tumors measured, 21.5% were <20 mm and 78.5% >20 mm. Larger tumors were associated with higher Ca19.9, T3-T4 and N1, higher grade, perineural invasion, R1 resections, more positive lymph nodes, and higher lymph node ratios (P < 0.05). Tumours <20 mm showed a better prognosis (33 vs 23 months; P < 0.01), but worse surgical results with higher pancreatic fistula (21.1% vs 14.6%; P < 0.01) and mortality rates (1.5% vs 0.3%; P = 0.04). PDAC size was associated with worse prognosis (hazard ratio 1.26, P = 0.02), together with Ca19.9, grading, and N1. When measured at imaging, tumor size was underestimated (median 23 vs 30 mm; P < 0.01) and did not influence prognosis CONCLUSIONS:: PDAC size >20 mm, measured at gross pathology, correlates with surgical outcomes and is an independent predictor of poor prognosis. Given that imaging underestimates size by about 20%, perhaps tumors that measure >20 mm at imaging should be considered for neoadjuvant treatment regardless of resectability.