Maria Pia Costa Santos, Maria Helena Oliveira, Cátia Cunha, Filipe Costa, Luísa Glória, Rui Maio, Marília Cravo
Gastroentérologie – 2019-04-07 – CO –
Introduction: Intraductal papillary mucinous neoplasms (IPMNs) and pancreatic intraepithelial neoplasms (PanINs) are usually multifocal and can be synchronous with pancreatic cancer. Main duct and/or high-grade dysplasia IPMNs and PanINs are high-risk lesions for development of pancreatic cancer. Diagnostic accuracy of CT/MRI for cystic lesions is low and PanINs are microscopic lesions detected only in the surgical specimen. Therefore, after partial pancreatic resection, these synchronous lesions in the pancreatic remnant may progress to invasive cancer. The aim of this study was to evaluate the incidence of synchronous pre-malignant lesions in the surgical specimens of patients treated for blio-pancreatic cancer.
Methods: Retrospective study including patients with bilio-pancreatic cancer submitted to pancreatic surgery [total pancreatectomy and partial resection (cephalic or corpo-caudal pancreatectomy)]. All surgical specimen was reviewed to evaluate the presence of synchronous pre-malignant lesions. Diagnostic accuracy of pre-operative CT/MRI for detection of cystic lesions was also assessed.
Results: We analysed 125 patients submitted to pancreatic surgery with curative intend. Of those, 97 had malignant lesions of the pancreas, Vater ampulla or common bile duct. In the surgical specimen, we found synchronous pre-malignant lesions in 30% (29/97) of patients (14 IPMNs, 9 PanINs and 6 IPMNs+PanINs) of which 20% (19/97) were high-risk lesions. The diagnosis of cystic lesions with pre-operative CT/MRI had an accuracy of 79%, sensibility of 27%, specificity of 98%, positive predictive value of 86% and negative predictive value of 79%. Synchronous pre-malignant lesions were more commonly found in patients operated for pancreatic adenocarcinoma [76% (22/29)] (P<0,001) and in specimens of total pancreatectomy as compared with partial pancreatic resection (53% vs. 25%, P=0.022).
Conclusions: In this study, 20% of patients who underwent pancreatic surgery for biliopancreatic cancer had high-risk synchronous pre-malignant lesions. Only one-third of the cystic lesions were detected in pre-operative CT/MRI. Synchronous pre-malignant lesions were more frequent after total pancreatectomy, which suggests that this association is still underestimated. These results raise the possibility that a segmental resection leaves behind a pancreatic remnant at risk of progression to invasive cancer. Therefore, in patients undergoing partial pancreatic resection we may consider an intra-operative pancreatoscopy or more intensive surveillance programs if the first strategy is not feasible