Intraductal papillary mucinous neoplasms (IPMNs) of the pancreas have drawn considerable interest in recent years as we begin to learn more about the natural history of this disease. It is now commonly accepted that these tumours can be classified into two main categories according to their origin in the gland—that is main duct IPMN (MD-IPMN) and branch duct IPMN (BD-IPMN). It is also well documented that IPMNs may progress through different stages of dysplasia into invasive carcinoma. It is, however, not well known whether all IPMNs ultimately progress into invasive cancer and if so what the timeline of this process is. In contrast to classical ductal adenocarcinomas of the pancreas, however, where patients always present with fully developed carcinoma with a dismal prognosis, many patients with IPMNs present early enough so that an intervention might prevent the development of pancreatic cancer. In fact, about 8–43% of patients with MD-IPMNs and 54–94% of patients with BD-IPMNs present with non-malignant lesions.1 Whereas it is well accepted that patients with MD-IPMN should undergo resection of the lesion at the time of diagnosis, current guidelines recommend non-surgical management of a certain subgroup of BD-IPMNs.1 Asymptomatic patients with tumours <30 mm in size without mural nodules and without a main duct dilation (>6 mm) fall into this category. Of note, these recommendations were not based on long-term follow-up of such patients but on the extremely low incidence of invasive cancer of patients initially presenting with these features. Recently, …