A novel scoring system for arterial invasion of pancreatic body and tail cancer based on multidetector row computed tomography and biomarkers

Abstract

Background/objectives: The absence of major-vessel involvement is a crucial factor in the resectability and prognosis of pancreatic cancer. However, arterial invasion cannot be evaluated adequately using imaging findings alone. We therefore developed a scoring system to assess arterial invasion by pancreatic adenocarcinoma using multidetector row computed tomography (MDCT) and serum tumor markers.

Methods: Twenty patients who underwent distal pancreatectomy and splenectomy for pancreatic adenocarcinoma were examined retrospectively using 4-, 16- or 64-row MDCT and serum tumor markers. Splenic arterial invasion was evaluated in terms of length of tumor contact, circumferential involvement (<180° or ≥180°) and deformity of vascular diameter. Preoperative expression of carbohydrate antigen 19-9 (CA19-9), DUPAN-2 and S-Pancreas-1 antigen (SPan-1) were also evaluated. The presence or absence of arterial invasion was confirmed histopathologically in all 20 cases.

Results: In 11 of 20 cases invasion into splenic arteries was observed histopathologically, mostly involving the external elastic lamina and periarterial nerves. Sensitivity, specificity and accuracy were 100%, 88.9% and 95%, respectively, for length of tumor contact (<16 mm or ≥16 mm), 90.9%, 77.8% and 85% for circumferential involvement (<180° or ≥180°), and 100%, 66.7% and 85% for deformity of vascular diameter. Furthermore, the sensitivity, specificity and accuracy were all increased to 100% when tumor markers were included in the score.

Conclusions: MDCT is a useful technique for diagnosing arterial invasion of pancreatic body and tail cancer, even in comparison with pathological examination; however, this new scoring system can be further complemented and made more reliable by measurements of serous tumor markers.