Gordon C. Hunt

Rapid Growth Rates of Suspected Pancreatic Cyst Branch Duct Intraductal Papillary Mucinous Neoplasms Predict Malignancy

AbstractBackgroundnThe majority of branch duct intraductal papillary mucinous neoplasms (BD-IPMNs) are recommended for surveillance imaging based on consensus guidelines. However, growth rates that should prompt concern for malignant transformation of BD-IPMN are unknown.AimsTo determine whether BD-IPMN growth can predict an increased risk of malignancy and define growth rates concerning for malignant BD-IPMN.MethodsThe study is a retrospective, multicenter study of suspected BD-IPMN patients undergoing imaging surveillance. All patients underwent EUS evaluation followed by surveillance imaging.ResultsTwo hundred and eighty-four patients with suspected BD-IPMN without worrisome features or high-risk stigmata were followed for a median 56xa0months and underwent a median of four imaging studies. Nine patients (3.2xa0%) developed malignant BD-IPMN. Malignant BD-IPMN grew at a faster rate (18.6 vs. 0.8xa0mm/year; Pxa0=xa00.05) compared to benign BD-IPMN. BD-IPMN growth rate between 2 and 5xa0mm/year was associated with an increased risk of malignancy with hazard ratio (HR) of 11.4 (95xa0% CI 2.2–58.6) when compared to subjects with BD-IPMN growth rate <2xa0mm/year (Pxa0=xa00.004). BD-IPMN growth rate ≥5xa0mm/year had a hazard ratio of 19.5 (95xa0% CI 2.4–157.8) (Pxa0=xa00.005). BD-IPMN growth rate of 2xa0mm/year had a sensitivity of 78xa0%, specificity of 90xa0%, and accuracy of 88xa0% to identify malignancy. Total BD-IPMN growth was also associated with increased risk of malignancy (Pxa0=xa00.003) with all malignant IPMNs growing at least 10xa0mm prior to cancer diagnosis.ConclusionsBD-IPMN growth rates ≥2xa0mm/year and total growth of ≥10xa0mm should be considered worrisome features for BD-IPMN at increased risk of malignancy.

Low Rates of Malignancy and Mortality in Asymptomatic Patients With Suspected Neoplastic Pancreatic Cysts Beyond 5 Years of Surveillance

BACKGROUND & AIMSnThe 2015 American Gastroenterological Association guidelines recommend discontinuation of surveillance of pancreatic cysts after 5 years, although there are limited data to support this recommendation. We aimed to determine the rate of pancreatic cancer development from neoplastic pancreatic cysts after 5 years of surveillance.nnnMETHODSnWe performed a retrospective multicenter study, collecting data from 310 patients with asymptomatic suspected neoplastic pancreatic cysts, identified by endoscopic ultrasound from January 2002 to June 2010 at 4 medical centers in California. All patients were followed up for 5 years or more (median, 87 mo; range, 60-189 mo). Data were used to calculate the risk for pancreatic cancer and all-cause mortality.nnnRESULTSnThree patients (1%) developed invasive pancreatic adenocarcinoma. Based on American Gastroenterological Association high-risk features (cyst size > 3 cm, dilated pancreatic duct, mural nodule), risks for cancer were 0%, 1%, and 15% for patients with 0, 1, or 2 high-risk features, respectively. Mortality from nonpancreatic causes was 8-fold higher than mortality from pancreatic cancer after more than 5 years of surveillance.nnnCONCLUSIONSnThere is a very low risk of malignant transformation of asymptomatic neoplastic pancreatic cysts after 5 years. Patients with pancreatic lesions and 0 or 1 high-risk feature have a less than 1% risk of developing pancreatic cancer, therefore discontinuation of surveillance can be considered for select patients. Patients with neoplastic pancreatic cysts with 2 high-risk features have a 15% risk of subsequent pancreatic cancer, therefore surgery or continued surveillance should be considered.

Recurrent Pneumothoraces After Diagnostic Colonoscopy

Question: A 37-yearold woman with history of stage IIA colon adenocarcinoma 4 years prior, underwent an unremarkable colonoscopy for intermittent abdominal pain and for surveillance. The next day, she experienced pleuritic right-sided chest pain; 3 days after colonoscopy, she presented to the emergency department with progressive right-sided chest pain and decreased breath sounds n examination. Chest radiography revealed a 10%–15% right-sided pneumothorax (Figure A), which was managed with Thoravent chest ube placement. Computed tomography (CT) of the abdomen and pelvis did not reveal pneumoperitoneum. Subsequently, the patient had spontaneous pneumothoraces, occurring at 1 and 4 months after the initial episode. Chest CT revealed recurrent pneumothoraces and ung blebs (Figure B). After mechanical pleurodesis and stapling of lung bleb failed, right lung wedge resection and talc pleurodesis was uccessful. Interestingly, the patient’s father also had history of spontaneous pneumothoraces, and recently had a partial nephrectomy for enal cell carcinoma. He had no prior history of colorectal carcinoma. What is the diagnosis, and what is the likelihood of there being a genetic component? See the GASTROENTEROLOGY web site (www.gastrojournal.org) for more information on submitting your favorite image to Clinical Challenges and Images in GI.