Diagnostic approaches for pancreatic cystic lesions

Abstract

Background: Cystic lesions of the pancreas (PCLs) may be inflammatory or proliferative and making an accurate and timely pre-operative diagnosis remains a significant clinical challenge. This is principally due to the heterogeneity of the pathological processes involved. PCLs constitute an entity with diverse histology and although infrequent, the possible potential for malignant transformation of these lesions and the opportunity for curative surgery mandates that our diagnostic approaches are up to date and evidence based. In addition, improved diagnostic accuracy is crucial to prevent unnecessary surgical procedures with the inevitable associated morbidity. Methods: This narrative review examines the current diagnostic benchmarks and identifies novel diagnostic techniques that warrant further consideration, a number of which are beginning to be included in routine clinical practice when these PCLs are being investigated. A computerized search was made of MEDLINE, EMBASE and PubMed using the search words 'diagnostic approaches to pancreatic cystic lesions'. All relevant articles in English language or with an English abstract were retrieved and additionally cross referenced. Conclusion: The increasing accuracy of available imaging techniques together with the wider availability of endoluminal ultrasound and the development of additional novel methods to assess PCLs presents an opportunity to significantly improve the pre-operative diagnosis rate. This is essential to classify the type of PCL and hence guide the management particularly with lesions where there is a likelihood of progression to more serious pathology. We have highlighted the need for a comprehensive and standardized algorithm for the diagnosis and management of PCLs.

Advances in the Diagnosis of Pancreatic Cystic Lesions

“…In a study on 86 patients with surgically resected IPMNs (58 benign, 28 malignant), the performances of contrast-enhanced CT and MRI were compared [ 31 ]. With both CT and MRI, the presence of an enhancing mural nodule ( p < 0.001), an abrupt change in the main pancreatic duct caliber ( p < 0.001), abnormal lymph nodes ( p = 0.006), a larger main pancreatic duct size ( p = 0.003) and a fast cyst growth rate ( p = 0.04) were more common in malignant than benign IPMNs.…”

“…However, the drawbacks of CT and PET/CT imaging include a significant radiation burden, particularly if regular surveillance or follow-up imaging is needed. Furthermore, the presence of mucin inside the cyst can lead to misdiagnosing some lesions as soft tissue rather than cystic content [ 31 ]. Moreover, it is difficult to distinguish macrocystic serous cystic neoplasms (SCNs) from other cystic tumors using conventional radiological methods, as evidenced by a study which showed that as much as 51 out of 100 resected and pathologically confirmed SCNs were preoperatively diagnosed as non-SCN lesions [ 33 ].…”

Comparison of Preoperative Imaging Modalities for the Assessment of Malignant Potential of Pancreatic Cystic Lesions

“…The inclusion criteria for relevant studies were as follows: (1) the study design should be diagnostic tests; (2) the patient population should consist of those with PCLs or IPMNs; (3) the index test should be imaging methods in a preoperative setting; (4) the sensitivity and specificity of 2 or more different imaging modalities should be compared in the same subjects for differentiating malignant from benign PCL or IPMN; and (5) histopathology, biopsy, or clinical follow-up data should be available as a reference standard. The duplicated publications were excluded, as were publications such as conference abstracts, review articles, case reports, editorials, letters, and notes, which do not contain original data.…”

“…With the widespread use of cross-sectional imaging studies, the prevalence of pancreatic cystic lesions (PCLs) is increasing 1 . In a population-based prospective study, nearly half of the patients undergoing MRI incidentally showed PCLs, and their number and size increased with age 2 …”

“…W ith the widespread use of cross-sectional imaging studies, the prevalence of pancreatic cystic lesions (PCLs) is increasing. 1 In a population-based prospective study, nearly half of the patients undergoing MRI incidentally showed PCLs, and their number and size increased with age. 2 Pancreatic cystic lesions are composed of various histological entities, and mucinous neoplasms have malignant potential, which makes them candidates for surgical resection.…”