Ovarian metastases of pancreatic adenocarcinoma: clinical presentation, role of surgery, and potential value of the mutational profile for the differential diagnosis with primary mucinous ovarian carcinoma.

BACKGROUND: Ovarian metastases (OM) of pancreatic adenocarcinoma (PA) (OM-PA) can mimic primary ovarian mucinous carcinoma (POMC) on imaging and histology. These metastases are often symptomatic and not highly chemosensitive, so that oophorectomy may be considered. AIMS: The aims of this study were to compare the characteristics of OM-PA and POMC, and discuss the role of surgery. PATIENTS AND METHODS: Clinical, imaging, and histological data of patients with OM-PA and POMC (2000-2017) in three tertiary centers were reviewed. Twenty-six genes were analyzed by next generation sequencing (NGS) on both primary PA and OM-PA. RESULTS: Twenty-two women with OM-PA (n = 13, 11 with surgical resection) or POMC (n = 9) were selected. OM-PA were smaller than POMC (p = 0.02); imaging, histological, and immunohistochemistry data did not clearly differentiate OM-PA from POMC in 12 of 22 cases (54%). Seven PA/OM-PA pairs were analyzed, and a concordant KRAS mutation was identified in all cases. In four OM-PA, concordant mutations were also found in TP53 (n = 3), SMAD4 (n = 1), MET (n = 1), and PDGFRA (n = 1) genes. The aim of oophorectomy in 11 OM-PA was for antalgic (n = 6) or curative (n = 5) intent. Pain improved in 4/6 of the former patients, but 2/6 had significant morbidity, and 2/6 died of rapid tumor progression. After oophorectomy, median progression-free and overall survivals were 6 (0-11) and 8 months (1-131), respectively. CONCLUSION: Analysis of mutation profiles in both primary PA and ovarian tumors, especially KRAS, can help to determine the pancreatic origin of OM-PA. Surgical resection of OM-AP in highly selected patients may improve pelvic symptoms but may also cause significant morbidity. The benefit to survival requires further studies.

Limited added value of contrast-enhanced ultrasound over B-mode for the subtyping of hepatocellular adenomas.

PURPOSE: To compare the features of hepatocellular adenoma subtypes (HCAs) in B-mode and contrast-enhanced ultrasound (CEUS). METHOD: Thirty-three patients (31 women [94 %] and two men [6%], median age [Q1-Q3] 43.5 years old [35-51]) with 44 pathologically proven and subtyped HCAs (including 29 inflammatory HCAs [I-HCA] and 15 HNF1-α inactivated HCAs [H-HCA]) who underwent CEUS were included. The features of HCA on B-mode and CEUS were independently reviewed by two radiologists and compared between HCA subtypes. RESULTS: I-HCAs were mostly hypoechoic (23/29, 79 %) or isoechoic (4/29, 14 %) with B-mode. Twelve of them (41 %) were heterogeneous. All H-HCAs except one demonstrated homogeneous hyperechogenicity (93 %) (p = 0.001). Moderate or marked liver steatosis was only observed in I-HCAs (12/29, 41 %) (p = 0.001). Arterial hyperenhancement was observed on CEUS in 27/29 (93 %) I-HCAs and in 14/15 (93 %) H-HCAs (p=0.98). Washout was present in 6/29 (21 %) I-HCAs and 1/15 (7%) H-HCAs (p=0.27). A total of 23/29 (79 %) I-HCAs and 15/15 (100 %) HCAs were homogeneous on portal and delayed phase acquisitions (p=0.04). The specificity for identifying an H-HCA was 100 % when the lesion was homogeneous and hyperechoic on B-mode, and the sensibility to rule out an H-HCA was 100 % if neither of these two features was present in a liver with obvious steatosis. CONCLUSIONS: Most CEUS features, especially enhancement patterns, do not significantly differ between HCA subtypes. When HCA is suspected on CEUS, B-mode features should be considered, and a combination of lesion hyperechogenicity, homogeneity and the absence of obvious liver steatosis may be useful to distinguish H-HCAs from I-HCAs.

Acute extrahepatic infectious or inflammatory diseases are a cause of transient mosaic pattern on CT and MR imaging related to sinusoidal dilatation of the liver.

PURPOSE: To report the association of a mosaic enhancement pattern on contrast-enhanced CT or MR imaging and hepatic sinusoidal dilatation (SD) with acute inflammatory conditions affecting extrahepatic organs. METHODS: From 2007 to 2012, patients with acute inflammatory diseases who underwent contrast-enhanced CT and/or MRI of the liver with a mosaic enhancement pattern were selected. Clinico-biological and other imaging features were collected at diagnosis and during follow-up. RESULTS: Sixteen patients were included (15 women, median age 27 years; range 18-68). Five women (33 %) were receiving oral contraceptives. Acute inflammatory diseases included pyelonephritis (n = 10), pancreatitis (n = 2), pneumonia (n = 1), septicemia (n = 1), active Crohn's disease (n = 1), and infectious colitis (n = 1). Median white blood cell count was 13,250 cells/µL (range 11,500-18,000 cells/µL) and CRP level 94 mg/L (range 60-121 mg/L). Mosaic enhancement pattern was present in the whole liver and was prominent in the subcapsular areas. Four patients underwent liver biopsy confirming SD. Eleven patients underwent follow-up imaging showing normalized aspect in 9/11 patients after a median of 2 months. CONCLUSION: Acute diseases of extrahepatic organs, associated with a marked systemic inflammatory syndrome should be added to the list of conditions causing a reversible hepatic sinusoidal dilatation as manifested by a mosaic enhancement pattern on contrast-enhanced CT or MR imaging. KEY POINTS: • Acute extrahepatic infectious/inflammatory diseases are a cause of transient MP. • In most patients, MP was seen during both arterial and portal venous phase. • In all patients, the mosaic enhancement pattern was diffuse, but more conspicuous in subcapsular areas. • MP was no longer seen after resolution of the acute disease. • No liver biopsy should be performed.

Hepatic hemangiomas: factors associated with T2 shine-through effect on diffusion-weighted MR sequences.

PURPOSE: To determine the frequency and factors associated with the presence of T2 shine-through effect in hepatic hemangiomas on diffusion-weighted (DW) magnetic resonance (MR) sequences. MATERIALS AND METHODS: This retrospective study was approved by institutional review board with waiver of informed consent. One hundred forty-nine consecutive patients with 388 hepatic hemangiomas who underwent a liver MR between January 2010 and November 2011 were included. MR analysis evaluated the lesion characteristics (signal intensities and enhancement patterns (classical, rapidly filling, delayed filling)), the presence of T2 shine-through effect on DW sequences (b values of 0, 150, and 600 s/mm2), and apparent diffusion coefficient (ADC) values. Multivariate analysis was performed to study the factors associated with the T2 shine-through effect. RESULTS: T2 shine-through effect was observed in 204/388 (52.6%) of hepatic hemangiomas and in 100 (67.1%) patients. Mean ADC value of hemangiomas with T2 shine-through effect was significantly lower than hemangiomas without (2.0±0.48 vs 2.38±0.45, P<.0001). On multivariate analysis, high signal intensity on fat-suppressed T2-weighted fast spin-echo images, hemangiomas with classical or delayed enhancement, and the ADC of the liver were the only significant factors associated with T2 shine-through effect. CONCLUSION: T2 shine-through effect is commonly observed in hepatic hemangiomas and is related to hemangiomas characteristics. Radiologists should be aware of this phenomenon which could lead to misdiagnosis. Its presence should not question the diagnosis of hemangiomas when typical MR findings are found.

MR findings of steatotic focal nodular hyperplasia and comparison with other fatty tumours.

OBJECTIVES: To correlate MR findings with pathology in steatotic FNHs and to compare the MR findings with those of other fatty tumours developed on noncirrhotic liver in a consecutive series of resected lesions. METHODS: Our population included resected FNH with intralesional steatosis (n = 25) and other resected fatty tumours selected as controls (hepatocellular adenomas and angiomyolipomas, n = 34). Lesions were classified into three groups: those with typical FNH without (group 1) or with (group 2) fat on MR and those with atypical lesions (group 3). In group 3, diagnostic criteria for other fatty tumours were applied. RESULTS: There were 9 lesions in group 1 (15.3 %), 4 in group 2 (16.8 %) and 46 in group 3 (77.9 %). Group 3 contained 12 FNHs (26 %) and all the other fatty tumours. In group 3, the association of lesion homogeneity, signal intensity similar to or slightly different from adjacent liver on in-phase T1- and T2-weighted sequences, and strong arterial enhancement was observed in 7/12 (58 %) of steatotic FNHs and 3/34 (9 %) of other tumours. CONCLUSION: On MR, fat within a typical FNH should not reduce the diagnostic confidence. We recommend further investigations including liver biopsy if necessary when fatty tumours exhibit atypical MR findings.