NCT01565200.

The use of imaging in colorectal cancer (CRC) has significantly evolved over the last twenty years, establishing important roles in surveillance, diagnosis, staging, treatment selection and follow up. The range of modalities has broadened with the development of novel tracer and contrast agents, and the fusion of technologies such as positron emission tomography (PET) and computed tomography (CT). Traditionally, the most widely used modality for assessing treatment response in metastasised colon and rectal tumours is CT, combined with use of the RECIST guidelines. However, a growing body of evidence suggests that tumour size does not always adequately correlate with clinical outcomes. Magnetic resonance imaging (MRI) is a more versatile technique and dynamic contrast-enhanced (DCE)-MRI and diffusion-weighted (DW)-MRI may be used to evaluate biological and functional effects of treatment. Integrated fluorodeoxyglucose (FDG)-PET/CT combines metabolic and anatomical imaging to improve sensitivity and specificity of tumour detection, and a number of studies have demonstrated improved diagnostic accuracy of this modality in a variety of tumour types, including CRC. These developments have enabled the progression of treatment strategies in rectal cancer and improved the detection of hepatic metastatic disease, yet are not without their limitations. These include technical, economical and logistical challenges, along with a lack of robust evidence for standardisation and formal guidance. In order to successfully apply these novel imaging techniques and utilise their benefit to provide truly personalised cancer care, advances need to be clinically realised in a routine and robust manner.

A 56-year-old man was referred with asymptomatic elevation of pancreatic hydrolase levels. Magnetic resonance imaging (MRI) delineated a pancreatic lesion with a low T1 and high T2 signal (• " Fig. 1). Endoscopic ultrasound (EUS) found an oval, well-defined, isoechogenic, homogeneous mass in the pancreatic parenchyma, without any vascular invasion and no locoregional lymph nodes (• " Fig. 2). Fine-needle aspiration (FNA) showed small epithelioid cells. Immunostaining was positive for antichromogranin, antisynaptophysin, and anti-KI-67 (5 %), and a few cells were positive for anti-CD56. This was consistent with a neuroendocrine tumor (NET). Octreotide positron emission tomography combined with computed tomography (PET-CT) showed a focal uptake into the pancreas without any other nonphysiological uptake (• " Fig. 3). CA19-9 and chromogranin levels were normal. Caudal pancreatectomy with spleen preservation was performed. Histological examination found no proof of NET but did reveal an intrapancreatic accessory spleen (IPAS) (• " Fig. 4). The postoperative period and follow-up were satisfactory. Accessory spleens may be found in 15 % of the population but are rarely located in the pancreatic tail (17 %) [1]. Most IPASs have a homogeneous contrast-enhanced appearance on CT and MRI, sharing features with hypervascular lesions (such as NETs) [1]. Octreotide scans have a high sensitivity for detection of gastrointestinal NET (70 %-95 %). The somatostatin receptors on the surface of splenic lymphocytes may lead to false diagnosis of NET [2]. Nuclear scintigraphic investigations such as those with 99m