ThTP1.3 Does radiological staging accurately predict histological stage in Whipple patients with pancreatic cancer? Results from an international multicentre study

Abstract

Abstract Aims Patients with a suspected malignancy of the pancreatic head should undergo preoperative radiological staging to ensure they are appropriate candidates for pancreatoduodenectomy (PD). Postoperatively, histological staging is performed as this guides adjuvant treatment and is useful for estimating prognoses. This study aimed to investigate the concordance of radiological and histological staging in patients with pancreatic ductal adenocarcinoma (PDAC). Methods Data were extracted from the Recurrence After Whipple’s (RAW) study, a retrospective study of PD outcomes (29 centres from eight countries, n=1484). Patients were excluded if: they had staging data missing, they underwent neoadjuvant chemo-/radiotherapy, or if radiological staging was performed for another malignancy. Pre- and postoperative stages were then compared. Results Of the 595 included cases, 20%, 40%, 26%, 4% and 12% of patients were radiological stage T1, T2, T3, T4, and TX, respectively, and 7% (OR: 3.4, 95% CI: 2.3-5.0), 11% (5.4, 4.0-7.4), 80% (0.1, 0.1-0.1), 3% (0.8, 0.4-1.8) and 1% (27.0, 8.4-86.3) were T1, T2, T3, T4 and TX, respectively. Tumour size was significantly larger on histology (median difference: 3mm, p<0.00001). 66%, 27% and 7% of patients were radiological stage N0, N1 and NX, respectively, and 23% (OR: 6.5, 95% CI: 5.0-8.4), 77% (0.1, 0.1-0.1) and 0.3% (22.5, 5.4-93.5) were histological stage N0, N1 and NX, respectively. Conclusions In patients who underwent PD for PDAC, preoperative imaging appeared to underestimate disease stage. Histologically, patients had larger, more advanced tumours and were significantly more likely to have involved lymph nodes.