Pancreatic mucinous cystoadenomas and cystoadenocarcinomas: differential diagnosis by means of MRI

Abstract

Objective: To determine the accuracy of MRI in differentiating mucinous cystoadenomas (MCAs) from mucinous cystoadenocarcinomas (MCACs) of the pancreas, with histopathological analysis as the reference standard, for better surgical planning. Methods: A total of 65 patients with histopathologically proven mucinous cystic neoplasms (MCNs) underwent MRI and surgery. Quantitative image analysis included size, septa and wall thickness and number of loculations. Qualitative image analysis included nodules; hyperintensity of the cystic content on T 1 weighted images; compression and/or infiltration of adjacent vessels or organs; and metastases. A comparison between MCAs and MCACs was performed with Student's t-test for quantitative variables and with Fisher test for qualitative variables. Receiver operating characteristic analysis was performed to determine the accuracy in the differential diagnosis between MCAs and MCACs on the basis of a score system obtained by giving 1 point for each quantitative and qualitative variable observed in each patient.Results: At histopathology, 43 lesions were MCAs and 22 lesions were MCACs. A statistically significant difference was observed for size .7cm (,0.001), septa and wall thickness .3 mm (,0.0001), number of loculations .4 (,0.0001), nodules (,0.0001), hyperintensity of the cystic content on T 1 weighted images (,0.0001), compression (,0.01) and/or infiltration (,0.01) of adjacent vessels or organs and metastases (,0.05). The best cutoff value to discriminate MCAs from MCACs was the presence of three features ( p , 0.001), with an accuracy of 91%. Conclusion: MRI has an accuracy of 91% in the differential diagnosis between MCA and MCAC, helping in identifying forms that could undergo parenchyma-sparing surgery (MCAs), reducing post-surgical morbidity and mortality. Advances in knowledge: In this study, the differentiation between MCAs and MCACs of the pancreas by means of MRI is addressed. The differential diagnosis allows selecting benign forms, susceptible of parenchyma-sparing surgery, with the advantage of reducing post-surgical morbidity and stratifying prognosis of MCNs.

Clinical diagnosis and management of pancreatic mucinous cystadenoma and cystadenocarcinoma: Single-center experience with 82 patients

“…Studies have drawn different conclusions regarding the specific threshold value of cyst diameter over which the risk of malignancy is increased. It is generally believed that the cyst wall diameter in malignant MCN is usually > 4 cm[ 15 ], or that a diameter of ≥ 6 cm is a risk factor for malignant tumors[ 11 , 16 , 17 ]. In addition, other manifestations suggestive of malignant MCA include peripheral calcification, irregularly contoured cyst walls, thickening of internal septations, increased papillary projections, intracystic nodules, local organ invasion, and vascular obstruction and compression.…”

“…In addition, other manifestations suggestive of malignant MCA include peripheral calcification, irregularly contoured cyst walls, thickening of internal septations, increased papillary projections, intracystic nodules, local organ invasion, and vascular obstruction and compression. Di Paola et al[ 16 ] studied 65 patients with MCNs who underwent magnetic resonance imaging and found that there may be a risk of malignant transformation if the diameter is greater than 7 cm, septa and wall thickness was > 3 mm, and there were nodules. In this study, the median diameter of MCA was 3.5 cm and that of MCC was 5.8 cm.…”

Classification, Morphology, Molecular Pathogenesis, and Outcome of Premalignant Lesions of the Pancreas

“…15,49,51 On imaging studies, larger cyst size, thickening of the septations within an MCN, and presence of an intracystic or adjacent solid mass are radiologic features that may suggest an associated invasive PDAC. 15,50,52 The cytopathologic features that are worrisome for invasive carcinoma arising from an MCN are similar to those for IPMN: nucleomegaly, clumped and irregular chromatin distribution, irregular nuclear contours, and crowding.…”

The potential of the malignancy of cystic neoplasms of the pancreas

“…Возраст пациента является значимым фактором увеличения риска развития карциномы из MCN [32]. Кроме того, независимыми факторами, увеличивающими риск малигнизации являются размер, толщина стенки и наличие внутрикистозного солидного компонента [38][39][40] Так же, как и IPMN, MCN гистологически делится на три типа в зависимости от тяжести диспластических изменений: I -MCN c дисплазией легкой или умеренной степени; II -MCN c дисплазией высокой степени (по сути рак in situ); III -MCN, ассоциированная с инвазивной карциномой [27].…”