Who Should Undergo Surgery for Pancreatic Cysts?
When should a patient with a pancreatic cystic lesion undergo surgery? How can we tell if the surgery will provide relief, or prevent death from pancreatic cancer, or burden a patient with an unnecessary procedure? Two articles in the October issue of Clinical Gastroenterology and Hepatology increase our understanding of when to recommend surgery for patients with pancreatic cysts.
The Sendai guidelines were developed in 2006 to guide management of patients with pancreatic cysts. They lead to detection of malignant mucinous lesions with a high degree of sensitivity but low specificity, resulting in many unnecessary resections. The guidelines were therefore revised in 2012 (the Fukuoka guidelines) and cysts >3 cm were reclassified as worrisome, rather than high risk.
Pavlos Kaimakliotis et al investigated whether the guidelines have accurately predicted which patients with suspected pancreatic mucinous cystic neoplasms, based on cross-sectional imaging findings, were later found to have advanced neoplasia in surgery.
They collected data from 194 patients with cystic lesions of the pancreas classified (based on cross-sectional imaging findings) according to the Sendai guidelines as high risk or low risk and according to the Fukuoka guidelines as high risk, worrisome, or low risk. Pathology analyses of samples collected during surgery were used determine whether the predictions were correct.
Advanced neoplasias were found in 36 patients (18.5%; 22 invasive cancers and 14 high-grade dysplasias). All patients found to have invasive cancers were accurately assigned to the Sendai guidelines high risk or Fukuoka guidelines high risk groups. However, 3 patients in the Sendai guidelines low-risk groups and 2 patients in the Fukuoka guidelines low-risk groups were found to have high-grade dysplasia.
Overall, there was no statistically significant difference between the guidelines in predicting which patients had advanced neoplasia. On multivariate analysis, the presence of a mural nodule (odds ratio, 2.88), dilated main pancreatic duct >10 mm (odds ratio, 7.44), or enhancing solid component (odds ratio, 2.92) increased risk for detection of advanced neoplasia in pancreatic cysts.
Kaimakliotis et al concluded that the Sendai and Fukuoka guidelines accurately determine which patients with pancreatic cysts have advanced neoplasia (see figure). The guidelines accurately recommended surgery for all patients found to have invasive cancer, although some patients with high-grade dysplasia were missed. Cyst size was not associated with advanced neoplasia.
In an editorial in the same issue, Mohamed O. Othman and Mark D. Topazian say that these findings focus our attention on the group of cysts with worrisome features. If all of these are sent for resection, the Fukuoka guidelines appear to perform almost identically to the Sendai guidelines.
Klaus Sahora et al investigated whether there is a subset of patients with intraductal papillary mucinous neoplasms (IPMNs) and a high risk of dying from other causes who would not benefit from pancreatic surgery. They collected data from 725 patients who underwent resection or had been under observation for IPMNs, with a median Charlson comorbidity index score of 3 (10% of patients had scores of 7 or more).
Of the entire cohort, 55% underwent surgery whereas the remaining 45% remained under observation.
After a median follow-up period of 5 years, 177 patients died (24%, 55% of deaths within 5 years of diagnosis); 78% of deaths were not related to IPMNs. The median survival time for all patients with Charlson comorbidity index score of 7 or more was 43 months. Multivariate regression analysis showed that the chance of non-IPMN−related death within 3 years of diagnosis was 11-fold higher for patients with a score of 7 or more than for patients with lower scores.
Sahora et al concluded that the Charlson comorbidity index score can identify patients with a high risk of death from factors other than IPMNs within a few years after diagnosis. These patients are therefore not likely to benefit from further IPMN observation or pancreatic resection.
Othman and Topazian wrote that lesions with worrisome features should be assessed with endoscopic ultrasound per the Fukuoka guidelines, although these guidelines require further validation. In addition, comorbidities are an important cause of death in patients with IPMNs, and those with a high comorbidity score generally may be better served by avoiding surgery, even if worrisome cyst features are present.
They say that both studies highlight the limitations of current diagnostic and management paradigms and the need for new approaches to mucinous pancreatic cysts.