Chapter 58 by Dr Maley and Dr Yeo is equally comprehensive in their superb discussion of cystic neoplasms of the pancreas. They focus predominantly on serous cystadenoma, mucinous cystic neoplasm (MCN), and intraductal papillary mucinous neoplasm (IPMN). Regarding serous cystadenoma, this histology demonstrates fascinating tumor biology. As mentioned by the authors, it is generally felt that serous cystadenomas do not have the biologic ability to metastasize to distant organs or regional lymph nodes. However, they can be locally invasive and erode into adjacent bowel (duodenum, transverse colon, stomach) and occasionally can obstruct the splenic vein (resulting in sinistral portal hypertension) or the superior mesenteric and/or portal veins (resulting in extrahepatic portal hypertension). Importantly, the diagnosis of (microcystic) serous cystadenoma can usually be made on high-quality CT imaging with or without the additional benefit of EUS because of its characteristic imaging appearance (unless the serous cystadenoma is macrocystic). When referring a patient for EUS to confirm a diagnosis of serous cystadenoma, we would recommend an FNA biopsy if the EUS is not consistent with this diagnosis or there appears to be discrepancy between CT or MRI imaging and the EUS appearance. As noted by the authors, serous cystadenomas are characterized by a cyst fluid CEA level that is usually undetectable or very low (<5 ng/mL). In 2011, the diagnosis of a serous cystadenoma is usually not difficult; however, knowing when to intervene with surgery is often challenging. As patient age and operative risk (medical comorbidities) increase, the benefit to surgery in an otherwise asymptomatic patient may be low. For example, it is relatively easy to understand a recommendation for surgery in an otherwise completely healthy 60-year-old patient with a 5- to 6-cm serous cystadenoma.7 However, the same pancreatic tumor in a 75-year-old patient with one or two coronary stents and a relatively sedentary lifestyle may not be the correct approach. In our practice, we try to carefully weigh risk versus benefit in asymptomatic patients.8 In addition, for serous cystadenomas that are less than 4–5 cm in size, we usually require that they demonstrate growth, over a period of observation, before proceeding with surgery. Our underlying philosophy is to avoid surgery-related mortality and major morbidity, especially in patients who are asymptomatic with a tumor histology such as serous cystadenoma that poses no risk for distant metastases.