Diagnostic Pitfall of Gastric Signet-Ring Cells: How to Diagnose a Benign Signet-Ring Cell From a Malignant One.

Sometimes non-neoplastic changes of the gastric mucosa mimic diffuse-type gastric carcinoma, specifically signet-ring cell adenocarcinoma. In fact, gastric epithelial cells undergoing signet-ring cell change have a cellular morphology that is almost identical to signet-ring cell adenocarcinoma, often leading to misdiagnosis. Accurate recognition of signet-ring cell change is essential to avoid overdiagnosis and overtreatment of signet-ring cell adenocarcinoma. Research on this topic is limited and clinicians lack formal diagnostic tools when signet-ring cells are detected in biopsy specimens. The aims of this study are 3-fold. Firstly, to increase the awareness of both clinicians and pathologists of this rare but highly significant entity. Secondly, to report 4 additional examples of signet-ring cell change and analyze them alongside signet-ring cell adenocarcinoma to compare their morphological and phenotypic features and their evolution over time. Finally, to highlight the potential utility of endoscopic resection to confirm the diagnosis. Cells in signet-ring cell change strongly express E-cadherin, show a wild-type p53 expression, and have a low Ki67 index. In contrast, cells in signet-ring cell adenocarcinoma strongly express p53, have high proliferation rates, and show either no or weak E-cadherin staining. Genetic analysis may be useful in identifying patients at risk of hereditary early diffuse gastric adenocarcinoma, which can mimic signet-ring cell change.

Auto-immune gastritis induced by pembrolizumab, an anti-PD-1, in a melanoma patient.

We report a case of a 67-years-old woman presenting a severe acute lymphocytic gastritis induced by pembrolizumab, an immune check point inhibitor (ICI). This gastritis was her third auto-immune adverse event after 5 years of treatment with pembrolizumab, it was metabolically active at the PET Scan and confirmed by analysis of the gastric biopsies. Pembrolizumab treatment cessation and high doses of corticosteroids completely normalized the stomach clinically, endoscopically and histologically. This patient was in complete remission of her metastatic melanoma. Therefore, pembrolizumab therapy was not restarted and the patient is still in remission 6 months later. This strategy is supported by recent publications describing a relapse rate inferior to 10% in patients in complete remission after 2 years of immunotherapy. Particularities of this case are: rareness of this adverse event, late onset after introduction of pembrolizumab, evocative PET scan image, specific endoscopic aspect and histology. In addition, the favorable oncologic evolution of the patient after treatment cessation confirms the prolonged remission after immunotherapy.

Endoscopic features, pathological correlates and possible origin of foveolar gastric metaplasia presenting as a duodenal polyp.

It has recently been shown that duodenal foveolar gastric metaplasia (FGM) sometimes presents as a polyp. The mechanism by which FGM develops into a polypoid lesion is unknown and it is unclear whether this form of FGM is indistinguishable from other polypoid lesions or whether endoscopists do not recognize it because they are unfamiliar with it. We identified and retrieved archival cases of FGM endoscopically suspicious for adenomatous polyp and examined their pathological, clinical and endoscopic features. Endoscopic features of the 13 identified FGMs presenting as polyps were heterogeneous and overlapping with those of adenomatous polyps. FGM was frequently associated with mucosal and submucosal Brunner's glands, but defining and recognizing hyperplasia of these glands remains difficult. Other pathological features could not explain the development of a polypoid lesion. The endoscopic features of FGM polyps are non-specific, overlapping with those of adenomatous polyps. FGM polyps probably acquire their polypoid aspect due to association with Brunner's gland hyperplasia (BGH), which also arises due to chronic inflammation and damage. Because BGH is ill-defined and difficult to recognize, while FGM is diagnosed easily, this type of polypoid lesions has until now only been recognized based on the presence of FGM, although FGM is most likely a secondary phenomenon and not the primary cause of the polyp.

Loss of protein phosphatase 2A regulatory subunit B56δ promotes spontaneous tumorigenesis in vivo.

Protein Phosphatase 2A (PP2A) enzymes counteract diverse kinase-driven oncogenic pathways and their function is frequently impaired in cancer. PP2A inhibition is indispensable for full transformation of human cells, but whether loss of PP2A is sufficient for tumorigenesis in vivo has remained elusive. Here, we describe spontaneous tumor development in knockout mice for Ppp2r5d, encoding the PP2A regulatory B56δ subunit. Several primary tumors were observed, most commonly, hematologic malignancies and hepatocellular carcinomas (HCCs). Targeted immunoblot and immunohistochemistry analysis of the HCCs revealed heterogeneous activation of diverse oncogenic pathways known to be suppressed by PP2A-B56. RNA sequencing analysis unveiled, however, a common role for oncogenic c-Myc activation in the HCCs, independently underscored by c-Myc Ser62 hyperphosphorylation. Upstream of c-Myc, GSK-3ß Ser9 hyperphosphorylation occurred both in the HCCs and non-cancerous B56δ-null livers. Thus, uncontrolled c-Myc activity due to B56δ-driven GSK-3ß inactivation is the likely tumor predisposing factor. Our data provide the first compelling mouse genetics evidence sustaining the tumor suppressive activity of a single PP2A holoenzyme, constituting the final missing incentive for full clinical development of PP2A as cancer biomarker and therapy target.

IgG4-related cholangitis: Case report and literature review.

CASE PRESENTATION: We describe a case of a patient who presents with jaundice, elevated cholestatic liver enzymes, an extreme weight loss and a midcholedochal stricture very suspect for a cholangiocarcinoma. In the conviction of malignancy, although the absence of anatomopathological prove, the patient underwent a choledochal resection. The anatomopathological specimen revealed no malignancy. In the year following resection, the patient keeps presenting with bile duct strictures and further weight loss. Ultimately the diagnosis of Ig G4-related cholangitis is withheld. Therapy with corticosteroids is initiated with a spectacular clinical, biochemical and radiographical result. DISCUSSION: IgG4-related cholangitis is the biliary presentation of IgG4-related disease, a recently discovered entity of fibroinflammatory masses which can affect virtually every organ in the body. It is characterized by a dense lymphoplasmacytic infiltrate, storiform fibrosis, obliterative phlebitis and a presence of > 30 IgG4-positive plasma cells per high power field. Main differential diagnosis contains cholangiocarcinoma and primary sclerosing cholangitis. Corticoids are cornerstone of therapy, with azathioprine frequently used as a maintenance in case of relapse. CONCLUSIONS: With this case we want to draw the attention to a rather uncommon cause of biliary obstruction, easily mistaken for a cholangiocarcinoma.

Laparoscopic liver resection compared to open approach in patients with colorectal liver metastases improves further resectability: Oncological outcomes of a case-control matched-pairs analysis.

AIMS: Liver resection is considered the standard treatment of colorectal metastases (CRLM). However, to date, no long term oncological results and data regarding repeat hepatectomy after laparoscopic approach are known. The aim of this study is to analyze single center long-term surgical and oncological outcomes after liver resection for CRLM. METHODS: A total of 57 open resections (OR) were matched with 57 laparoscopic resections (LR) for CRLM. Matching was based mainly on number of metastases, tumor size, segmental position of lesions, type of hepatectomy and type of resection. RESULTS: Morbidity rate was significantly less in the LR group (p = 0.002); the length of hospital stay was 6.5 ± 5 days for the LR group and 9.2 ± 4 days for the OR group (p = 0.005). After a median follow up of 53.7 months for the OR group and 40.9 months for the LR group, the 5-y overall survival rate was 65% and 60% respectively (p = 0.36) and the 5-y disease free survival rate was 38% and 29% respectively (p = 0.24). More patients in the LR group received a third hepatectomy for CRLM relapse than in the OR group (80% vs. 14.3% respectively; p = 0.015). CONCLUSIONS: Laparoscopic resection for CRLM offers advantages in terms of reduced blood loss, morbidity rate and hospital stay. It provides comparable long-term oncological outcomes but can improve further resectability in patients with recurrent disease.

Calciphylaxis: a rare complication in alcoholic liver disease.

Calciphylaxis, or calcific uremic arteriolopathy (CUA) is a rare but well described entity in patients with endstage renal disease (ESRD) and/or hyperparathyroidism. CUA is characterized by systemic acute calcification of the small and intermediate dermal vasculature that can lead to epidermal ischemia, ulceration, and necrosis. Cutaneous lesions of calciphylaxis characteristically begin as tender, violaceous, livedoid discolorations. The mechanisms of disease remain poorly understood although abnormal bone and mineral metabolism and hyperparathyroidism can contribute to CUA. Therapeutic strategies are of unproven benefit and mortality remains high. Calciphylaxis has also been extremely rarely reported in patients without ESRD and/or hyperparathyroidism. We report an unusual case of calciphylaxis in a patient with alcoholic liver cirrhosis and normal renal function, without any alteration in the phosphocalcic and parathyroid hormone (PTH) metabolisms.

Value of DCE-MRI and FDG-PET/CT in the prediction of response to preoperative chemotherapy with bevacizumab for colorectal liver metastases.

BACKGROUND: The purpose of this study was to assess the role of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and (18)F-fluorodeoxyglucose positron emission tomography computed tomography (FDG-PET/CT) for evaluation of response to chemotherapy and bevacizumab and for prediction of progression-free survival (PFS) in patients with metastatic colorectal cancer (mCRC) with potentially resectable liver lesions. METHODS: A total of 19 mCRC patients were treated with FOLFOX/FOLFIRI and bevacizumab followed by surgery. Dynamic contrast-enhanced magnetic resonance imaging and FDG-PET/CT were performed before treatment and after cycle 5. PET results were quantified by calculating maximum standardised uptake value (SUV(max)) whereas area under the enhancement curve (AUC), initial AUC (iAUC) and the endothelial transfer constant (K(trans)) were used to quantify DCE-MRI. Pathological analysis of the resection specimen was performed, including measurement of microvessel density (MVD) and proliferation index. RESULTS: Both AUC and iAUC were significantly decreased following bevacizumab therapy (median change of 22% (P=0.002) and 40% (P=0.001) for AUC and iAUC, respectively). Progression-free survival benefit was shown for patients with >40% reduction in K(trans) (P=0.019). In the group of radiological responders, the median baseline SUV(max) was 3.77 (IQR: 2.88-5.60) compared with 7.20 (IQR: 4.67-8.73) in nonresponders (P=0.021). A higher follow-up SUV(max) was correlated with worse PFS (P=0.012). Median MVD was 10.9. Progression-free survival was significantly shorter in patients with an MVD greater than 10, compared with patients with lower MVD (10 months compared with 16 months, P=0.016). CONCLUSION: High relative decrease in K(trans), low follow-up SUV(max) and low MVD are favourable prognostic factors for mCRC patients treated with bevacizumab before surgery.

Symptomatic bilateral choroidal metastasis from breast cancer as first clinical sign of advanced metastatic tumor disease 31 years after diagnosis.

We report a 62-year-old caucasian woman with bilateral choroidal metastases as only clinical presenting sign of advanced metastatic tumour disease. She presented with decreased vision in the left eye since 5 days. She was treated for breast cancer 31 years before. Fundoscopy and ultrasound analysis showed a large choroidal metastasis in the left eye and one asymptomatic lesion in the right eye. Systemic screening revealed multiple lung and bone metastases. Health practitioners should be aware that choroidal metastasis from breast carcinoma can present throughout life. Small asymptomatic lesions may be detected that still can be treated effectively.

The multicenter Belgian survey on liver transplantation for hepatocellular failure after bariatric surgery.

The prevalence of obesity has grown dramatically over the last decades, with nonalcoholic steatohepatitis increasingly observed. Therapeutic options for morbid obesity include bariatric surgery. Fatal liver failure (LF) has been recorded after jejunoileal bypass (JIB) but is controversial after biliopancreatic diversion (BPD, Scopinaro operation). We performed a survey on the frequency of liver transplantation (LT) after bariatric surgery in Belgium. An enquiry was sent to all Belgian liver transplant centers to investigate the occurrence of subacute and chronic LF after bariatric surgery. After weight-reduction surgery, 10 patients in 3 Belgian transplant centers were listed for LT due to severe hepatocellular failure. Nine of them had undergone a Scopinaro operation and 1 a jejunoileal bypass. The median time to develop LF was 5 years. The patient with JIB developed chronic LF after 25 years. Seven patients were transplanted; two died awaiting a graft and one is still on the waiting list. After LT, 1 patient developed rapid reappearance of LF at 10 months, requiring retransplantation. Two recipients died after LT because of multiorgan failure shortly after transplantation. In another case, a de novo cancer was fatal at 6 years' follow-up. The remaining recipients were doing well. According to this survey, the BPD operation carries a potential risk of LF. However, because there were only 10 cases, we remain unaware of the actual incidence of Scopinaro operation-induced LF. We advise strict follow-up of liver function and timely dismantling of BPD.

A unique combination of celiac disease, mesenteric lymph node cavitation, splenic atrophy and necrotizing hepatitis.

We report on a patient who was diagnosed six years before with celiac disease, with a current combined problem of asplenism, mesenteric cysts and elevated liver function tests. The implications of splenic atrophy mimic those of post-splenectomy patients. Mesenteric lymph node cavitation is a rare complication of celiac disease that is most often associated with splenic atrophy. The pathogenesis is unknown. The clinical implications of the cavitated mesenteric lymph nodes are unclear. The association of celiac disease with liver disease was reported many years ago, but only recently these associations have been more clearly defined. Liver involvement shows a clinical spectrum varying from nonspecific reactive hepatitis, chronic active hepatitis, steatohepatitis to frank cirrhosis. Associations with autoimmune hepatitis, autoimmune cholangitis, primary biliary cirrhosis and primary sclerosing cholangitis have been described. In our patient, we found no obvious cause for the necrotizing hepatitis and the negative auto-antibodies made it impossible to firmly establish the diagnosis of autoimmune hepatitis. The causal relationship with celiac disease, if any, remains unproven.

The clinicopathological and prognostic relevance of cytokeratin 7 and 19 expression in hepatocellular carcinoma. A possible progenitor cell origin.

AIMS: Cytokeratin (CK) 7 and CK19 expression, present in hepatic progenitor cells (HPCs) and in cholangiocytes but not in normal hepatocytes, has been reported in some hepatocellular carcinomas (HCCs); however, the incidence and relevance of this expression in HCC in Caucasians is not known. Therefore, our aim was to study the occurrence and clinicopathological characteristics of HCC expressing CK7 and/or CK19 in 109 Caucasian patients. METHODS AND RESULTS: The expression of hepatocellular differentiation markers (Hepar, canalicular polyclonal carcinoembryonic antigen), biliary/progenitor cell markers (CK7, CK19), alpha-fetoprotein (AFP), p53 and beta-catenin in HCC was semiquantitatively assessed by immunohistochemistry. Of 109 HCCs, 78 were CK7-/CK19- (72%), 13 CK7+/CK19- (12%), seven CK7-/CK19+ (6%), 11 CK7+/CK19+ (10%). CK19 expression was significantly associated with elevated serum AFP (400 ng/ml) (P = 0.023), tumour AFP expression (P < 0.0001), presence in serum of anti-hepatitis B core (P = 0.016), less fibrosis in non-neoplastic parenchyma (P = 0.009) and less nuclear beta-catenin expression (P = 0.021). CK7 expression was significantly associated with elevated serum bilirubin (> 2 mg/dl) (P = 0.0005) and less nuclear beta-catenin expression (P = 0.003). HCC expressing CK19 had a higher rate of recurrence (P = 0.009, hazard ratio 12.5, n = 31) after liver transplantation compared with CK19- tumours. CONCLUSIONS: In our series, 28% of HCCs contained cells expressing CK7 and/or CK19. They potentially derive from HPCs. The higher recurrence rate of CK19+ HCC after transplantation suggests a worse prognosis for these HCCs compared with CK19- HCC.

A stable model of cirrhotic portal hypertension in the rat: thioacetamide revisited.

BACKGROUND: Cirrhotic animal models are vital to investigate complications of chronic liver disease. We chronologically characterized the effect of thioacetamide, administrated orally and adapted weekly to weight changes, focusing on the optimal moment to obtain all typical features of portal hypertension and cirrhosis. MATERIALS AND METHODS: Male Wistar rats, 200-250 g, were intoxicated for 6, 12 or 18 weeks (n = 8 per group), respectively, and compared with age-matched controls (n = 4 per group). An in-situ perfusion model was used to evaluate intrahepatic resistance and endothelial function. Splanchnic blood flow and portosystemic shunting were assessed by a perivascular flow probe. RESULTS: Rats intoxicated for 6 or 12 weeks had no mortality and histologically showed hepatitis and advanced fibrosis, respectively. At 18 weeks, mortality was 16% (on a total of 56 animals) and only at that moment all animals showed homogenous macronodular cirrhosis with signs of high-grade hepatocellular dysplasia. Portal hypertension was present at 12 weeks (11 +/- 0.4 vs. 5.9 +/- 0.4 mmHg, P < 0.001), but was not associated with the hyperdynamic state until 18 weeks (12.1 +/- 0.8 vs. 5.6 +/- 0.5 mmHg, P < 0.001). At this latter time-point, we also observed increased intrahepatic resistance associated with endothelial dysfunction, hyperresponsiveness to vasoconstrictors, splanchnic hyperaemia and portosystemic shunting. These alterations were associated with increased systemic levels of nitrate/nitrite and thromboxane A(2). CONCLUSION: Thioacetamide, adapted to weekly weight changes, leads to a homogenous, reproducible model of cirrhosis in the rat in 18 weeks, which is associated with all the typical characteristics of portal hypertension, including endothelial dysfunction.

Microscopic colitis with giant cells.

AIMS: Collagenous colitis and lymphocytic colitis are the two types of microscopic colitis with specific morphological features. In this report we describe a new histopathological subtype of microscopic colitis. METHODS AND RESULTS: Colonoscopy in four patients with chronic watery diarrhoea showed no macroscopic abnormalities. The random biopsies from the colon showed subepithelial multinucleated giant cells in combination with the features of collagenous colitis in three patients and lymphocytic colitis in one patient. These multinucleated giant cells were positive for CD68. The density of macrophages was highest in the most superficial part of the lamina propria. In one patient, a previous biopsy showed features consistent with collagenous colitis without multinucleated giant cells. Treatment with budesonide led to the disappearance of diarrhoea in all four patients. CONCLUSIONS: The clinical and histopathological features of the four presented patients indicate that there exists a histopathological subtype of microscopic colitis characterized by the presence of subepithelial multinucleated giant cells, which probably arise from fusion of subepithelial macrophages. Analysis of more patients with this histopathological subtype of microscopic colitis is necessary to determine whether they also form a clinically distinct group.