Lymphangiogenesis in the liver of biliary atresia.

BACKGROUND: Lymphatic vessels (LVs) play a crucial role in immune reactions by serving as the principal conduits for immune cells. However, to date, no study has analyzed the morphological changes in the LVs of patients with biliary atresia (BA). In this study, we aimed to determine the morphological changes in the LVs irrigating the liver in patients with BA, elucidate their correlations with the morphology of the portal vein (PV) branches, and discuss their etiopathogenetic significance. METHODS: Morphometric analyses of liver biopsy specimens from patients treated between 1986 and 2016 were performed. The parameters measured were as follows: the whole liver area of the specimen, fibrotic area, number of LVs, LVs without patent lumen (designated as Ly0) and PV branches, and diameters of the LVs with patent lumen and the PVs. RESULTS: The numbers of LVs, Ly0, and PV branches per unit area of the whole liver specimen were significantly higher in patients with BA than in control participants with liver disease and those with normal livers. However, no correlation was observed between the fibrotic area and the average diameter of LVs or PVs, and between the fibrotic area and the number of LVs or PV branches. Furthermore, no correlation was observed between the total number of LVs and the number of PV branches. CONCLUSIONS: The present study showed a significant increase in the number of total LVs and Ly0, characterized by a high Ly0 to total LVs ratio, suggesting that lymphangiogenesis occurs in the liver of patients with BA.

Histological significance of hepatitis-like findings in biliary atresia: An analysis of 34 Japanese cases.

BACKGROUND: Hepatocellular injury including multinuclear changes are common histological features in biliary atresia (BA), as well as in neonatal hepatitis. To date, however, no reports have examined how those findings correlate with the prognosis of BA. We clarified the clinical implications of hepatitis-related changes in BA on histological analysis. METHODS: We retrospectively reviewed 34 cases of BA treated over the past 30 years at Ibaraki Children's Hospital. Liver biopsy specimens during Kasai procedures were evaluated for hepatocyte multinuclear change, ballooning, and acidophilic body, hereby defined as hepatitis-like findings (HLF). Each finding was semi-quantitatively scored as 0-2, and their sum was defined as the HLF score, ranging from 0 to 6. We examined the correlation between HLF score and total bilirubin (T-Bil), direct bilirubin (D-Bil), and other liver function test results at the Kasai procedure, as well as 1 week, and 1, 3, and 6 months after the Kasai procedure. Subsequently, HLF score was compared between native liver survivors (NLS; n = 16) and non-NLS (n = 18) for long-term analyses. RESULTS: Hepatitis-like findings score except for aspartate aminotransferase (AST), had no correlation with the preoperative data. HLF score was positively correlated, however, with T-Bil, D-Bil, and AST at 1 week and 1 month after the Kasai procedure (1 week: P = 0.009, 0.023, and 0.019; 1 month: 0.022, 0.019, and 0.013, respectively). HLF score was not significantly different between the NLS and non-NLS groups. CONCLUSION: Higher HLF score at Kasai procedure is an indicator of poor liver function at short-term follow up.

Microvascular proliferation of the portal vein branches in the liver of biliary atresia patients at Kasai operation is associated with a better long-term clinical outcome.

AIM OF THE STUDY: We previously showed an increased number of smaller portal vein (PV) branches in the portal areas of liver biopsy specimens of biliary atresia (BA) patients. We evaluated the correlation between this histopathological feature and the prognosis. PATIENTS AND METHODS: Twenty-five consecutive patients with BA encountered between 2000 and 2012 were classified into three prognostic groups based on their postoperative outcomes: Excellent (n = 11) for native-liver survivors with a normal liver function, Good (n = 6) for native-liver survivors with liver dysfunction, and Poor (n = 8) for survivors after liver transplant or on a waiting list. Data from morphometrical analyses, including the fibrotic portal area, numbers of PVs, diameter and total area of PV branches, were statistically compared among the three groups. MAIN RESULTS: The number of PV branches per unit area of the whole-liver specimen in the poor prognostic group was significantly lower than that in the excellent group (3.1 ± 0.6 vs. 5.2 ± 2.0/mm2, p = 0.03). There were no significant differences in the other parameters. CONCLUSIONS: This is the first report on the relationships between morphometrically analyzed PV branches and the postoperative course in BA patients. The portal venous system is involved as the primary lesion in BA.

Morphometric demonstration of portal vein stenosis and hepatic arterial medial hypertrophy in patients with biliary atresia.

PURPOSE: Portal hypertension in patients with biliary atresia (BA) is generally thought to result from portal vein (PV) narrowing secondary to hepatic fibrosis. To test the hypothesis, we morphometrically analyzed the PVs and hepatic arteries (HAs). METHODS: Morphometrical analyses of 25 BA and 26 non-BA liver biopsy specimens from patients treated from 2000 to 2014. The total specimen area, the fibrotic portal area, vessel diameter and medial thickness of the HAs were measured. RESULTS: The PV diameter in BA patients was significantly smaller than that in non-BA patients. In BA, the numbers of normal-sized PVs and capillaries were decreased and increased, respectively. The PV diameter was not significantly correlated with the degree of fibrosis. We newly found that medial hypertrophy and the HA diameter increased with the number of endothelial cells in BA. The PV diameter was not significantly correlated with the medial thickness and was positively correlated with the HA diameter in BA. CONCLUSIONS: The narrowing of the PV is unlikely to occur secondarily to liver fibrosis. The medial hypertrophy of the HA is not correlated with the decrease in the PV blood flow. These findings seem to be unique to the primary vascular lesions of BA.

Primary meningeal myxoid liposarcoma with aggressive behavior after recurrence: case report.

Although liposarcomas are the most common soft tissue sarcomas, their intracranial variants are extremely rare. Here, we present a case of a primary intracranial myxoid liposarcoma in a 23-year-old Japanese man who presented with generalized seizures and a mass in the left frontal lobe. The tumor was totally removed, and histological analyses pointed to liposarcoma. Thirteen years after his initial treatment, the patient presented with right-side weakness and local recurrence of tumor was discovered. Histology from the second resection confirmed the diagnosis of myxoid liposarcoma. Shortly after the second resection, progressive, new intracranial lesions were observed and despite a third resection, extensive intracerebral invasion by the tumor proved fatal. The histological features of myxoid liposarcoma were essentially similar with each recurrence, but the aggressive tumor behavior after the second operation did not align with expectations based on histological classification.

The accumulation of regulatory T cells in the hepatic hilar lymph nodes in biliary atresia.

PURPOSE: A proposed etiopathogenesis of biliary atresia (BA) involves T-cell-mediated inflammatory bile duct damage and progressive hepatic fibrosis. Pediatric surgeons often observe swelling of the hepatic hilar lymph nodes during the Kasai procedure. Given the importance of regulatory mechanisms in immune responses, the present study was designed to analyze the quantitative changes of regulatory T cells (T reg cells) in the hepatic hilar lymph nodes (hepatic hilar LNs) and peripheral blood (PB) in BA. METHODS: The hepatic hilar LNs and PB obtained during the Kasai procedure were analyzed by flow cytometry. The ratios of total and active Tregs to the total CD4+ cells in the PB and the hepatic hilar LNs were compared. RESULTS: In patients with BA, the ratios of both the total and active T reg cells in the hepatic hilar LNs were higher than those in the PB (total T reg cells: PB vs. LN; P < 0.001; active T reg cells: PB vs. LN; P = 0.001). In BA patients, the increase in the ratio of active T reg cells to the CD4 + cells in the LNs in comparison to the PB was greater than that in control patients. The ratio observed in the BA patients was almost double the ratio observed in the control patients. The median LN/PB ratio in the BA patients was 3.1, while that in controls was 1.6 (P = 0.03). CONCLUSION: The present study showed that the ratios of both total T reg cells and active T reg cells were higher in the hepatic hilar lymph nodes of BA patients. This finding could shed light on the pathogenesis of BA.

Unique manifestations of biliary atresia provide new immunological insight into its etiopathogenesis.

Biliary atresia (BA) is a unique cholestatic disease of newborns with a background of exaggerated immune response in the liver of unknown mechanism. Three hypotheses have been proposed; autoimmune type of cholangiopathy triggered by virus infection, graft-versus-host disease type of immune-mediated disease associated with maternal microchimerism and ductal plate malformation theory. Researchers on virus infection theory have experimentally explored immune process causing cholangiopathy on murine models of this disease, while in maternal microchimerism hypothesis were detected maternal cells in the BA patients' liver, of which roles are yet to be determined. Ductal plate malformation theory is an intriguing hypothesis in the sense that it suggests the onset of this disease is in the first trimester. This theory can be secondary to either one of these two immune-related insults. In this review, four unique points are focused; (1) the timing of onset, (2) hepatitis-like pathological picture, (3) heterogenous atrophy of the liver segments when advanced, and (4) swollen lymph nodes at the porta hepatis. These unique clinicopahtological aspects of this disease should be well explained by these hypotheses.

Reactive swelling of the regional lymph nodes in patients with stage II colorectal cancer as a prognostic factor.

The aim of this study was to examine the relationship between reactive swelling of regional lymph node (LN) and survival in colorectal carcinoma. We retrospectively studied 170 patients with surgically resected colorectal carcinoma histopathologically diagnosed as stage II (pStage II). These patients were classified into two groups:a) a "reactive LN swelling" group (clinically diagnosed as positive for LN metastasis, but pathologically negative) and b) a "no LN swelling" group. Survival analyses of the two groups showed that overall survival (OS) and disease-specific survival (DSS) were longer in the reactive LN swelling group than in the no LN swelling group in patients with total colorectal and right-sided colon cancer. Multivariate analyses revealed that reactive LN swelling was an independent prognostic factor in OS and DSS in patients with right-sided colon cancer. Reactive swelling of regional LN is regarded as an expression of local immune responses, which could explain the present results.

Defining lymphocyte-predominant breast cancer by the proportion of lymphocyte-rich stroma and its significance in routine histopathological diagnosis.

Lymphocyte-predominant breast cancer (LPBC) defined by the density of stromal lymphocytes shows favorable behavior. However, considerable distribution heterogeneity of lymphocytes is a major problem. The present study defined LPBC by the proportion of lymphocyte-rich stroma with the cut-off values of 30, 50, and 75%, and clinicopathologically analyzed mainly LPBC (area > 30%) defined by the cut-off value of 30%. LPBCs (area > 30%), 39 cases in total, were composed mainly of triple-negative and HER2(+) /ER(-) subtypes, without any luminal A-like subtype. LPBCs were composed predominantly of histological grade 3 tumors, without any grade 1 lesions. Multivariate analyses on 477 consecutive tumors revealed that ER-negativity and grade 3 status associated significantly with LPBC. LPBC (area > 30%) showed better disease-free survival than grade-matched controls, and it was a good indicator of complete pathological remission after pre-operative chemotherapy. Patients with LPBC with the cut-off value of 50% and that of 75% showed 100% disease-free survival. These results demonstrated the validity of our definition of LPBC. Our data also suggest that de-differentiated cancers without TILs could be regarded as high-grade cancer without lymphocyte-mediated responses. In conclusion, the definition of LPBC by the proportion of lymphoid stroma is useful for prognostication of high grade breast cancer in routine diagnosis.

Non-papillary serous cystadenoma of the epididymis associated with infected hydrocele of the testis: A case report.

A 50-year-old Japanese man with enlargement of the right scrotum was presented to our hospital. Preoperative examination confirmed a multilocular cyst with septa attached to the testis. Radical orchiectomy was performed. Pathological examination revealed closely-located two cysts; larger one was infected hydrocele testis, and smaller one was epithelial cyst, which were immunohistochemically positive widely for estrogen receptor (ER) and partly for progesterone receptor (PR). We concluded that the smaller cyst was serous cystadenoma of the epididymis.

C-C Chemokine 21-Expressing T-cell Zone Fibroblastic Reticular Cells, Abundant in Lymph Nodes, Are Absent in Cancer Lymphoid Stroma.

Cancer tissue generally possesses an immunosuppressive microenvironment. However, some cancers are associated with lymphoid stroma (i.e., a widely developed tertiary lymphoid structure). The T-cell zone (paracortex) of secondary lymphoid organs, particularly lymph nodes, is characterized by an abundance of T-cell zone fibroblastic reticular cells (TCZ-FRCs) that express C-C motif chemokine ligand 21 (CCL21) and smooth muscle actin (SMA). We analyzed the presence of TCZ-FRCs in 30 cases of carcinomas with lymphoid stroma of the breast, stomach, colon, tongue, and skin. Immunohistochemistry corroborated the abundance of CCL21+ SMA+ TCZ-FRCs in the normal lymph nodes. In sharp contrast, all 30 carcinomas with lymphoid stroma displayed no CCL21+ SMA+ TCZ-FRCs despite the affluence of T cells. Real-time reverse transcription polymerase chain reaction confirmed a marked decrease in the messenger ribonucleic acid expression of CCL21 and its receptor C-C motif chemokine receptor 7 in cancer lymphoid stroma compared to that in lymph nodes. Next, we analyzed the T cell phenotypes. The cancer lymphoid stroma demonstrated an abundance of CD3+ CD62L- memory-type T cells, in contrast to the presence of CD3+ CD62L+ naïve- and central memory T cells in the T cell zone of lymphoid tissues. Our data demonstrated the following: 1) Cancer lymphoid stroma lacked TCZ-FRCs with abundance of more activated T cells than in lymph nodes and 2) these were common phenomena in cancer lymphoid stroma irrespective of the histological types and organs involved.

High levels of FOXP3⁺ regulatory T cells in gastric MALT lymphoma predict responsiveness to Helicobacter pylori eradication.

BACKGROUND: Although Helicobacter pylori eradication is a first-line treatment of gastric MALT lymphoma, roughly 25% of patients do not respond to treatment. CD4⁺ FOXP3⁺ regulatory T (Treg) cells regulate immune responses in physiological conditions and various inflammatory conditions, including H. pylori-associated diseases. Our goal was to determine how Treg cells affect responsiveness to H. pylori eradication therapy. MATERIALS AND METHODS: We performed dual immunohistochemistry for CD4 and FOXP3 to evaluate the prevalence of FOXP3⁺ Treg cells in the stomach of 63 patients with MALT lymphoma and 55 patients with chronic active gastritis. Receiver operating characteristic analysis was carried out to determine the best cut-off point in differentiating H. pylori eradication responders from nonresponders. RESULTS: Both the FOXP3⁺/CD4⁺ cell ratio and the absolute number of FOXP3⁺ cells per high-power field in MALT lymphoma were significantly greater in H. pylori eradication responders compared with nonresponders, suggesting that Treg cells function in regression mechanisms of MALT lymphomas. Cut-off points with good sensitivities and specificities were obtained to predict eradication outcome. CONCLUSIONS: A high number of Treg cells or a high ratio of Treg cells to the total number of CD4⁺ T cells in gastric MALT lymphoma could predict responsiveness to eradication therapy.

Granuloma cells in chronic inflammation express CD205 (DEC205) antigen and harbor proliferating T lymphocytes: similarity to antigen-presenting cells.

Granulomas are classified as immune or foreign body granulomas. Of these, the immune granulomas, a hallmark of granulomatous inflammation, are closely related to cell-mediated immune responses. The aim of the present study is to characterize immune granuloma cells in 33 patients with granulomatous inflammation focusing on the expression of CD205 (DEC205), a cell surface marker of antigen presenting cells, and their spatial relationship to T cells. CD205 was frequently expressed by immune granuloma cells, in contrast to foreign body granuloma cells that lacked CD205 expression. T cells were not only distributed in a lymphocyte collar around the granuloma, but also present among the granuloma cells (termed 'intra-granuloma T cells'). Intra-granuloma T cells stained positive for Ki-67 (median positivity = 9.4%) by double immunostaining for CD3 and Ki-67. This indicated the presence of proliferative stimuli within the granuloma that could activate the intra-granuloma T cells. The labeling index of Ki-67 in intra-granuloma T cells was significantly higher than that of T cells in the lymphocyte collar (P < 0.0001) or T cells in the T cell zone (paracortex) of chronic tonsillitis or reactive lymphadenitis (P = 0.002). These data indicate a close similarity between immune granulomas and antigen presenting cells.

Malignant Pleural Mesothelioma (MPM) Presenting as Hydropneumothorax.

An 86-year-old man presented with bilateral lower limb edema and was found to have hydropneumothorax on chest radiography. CT revealed a substantial pleural effusion and plaques. The patient had a history of working in a stone workshop, but the extent of asbestos exposure remained unknown. Thoracic drainage and subsequent thoracoscopic surgery confirmed the presence of biphasic malignant mesothelioma through pathological examination. Hydropneumothorax as a presentation of malignant pleural mesothelioma (MPM) is rare, with only a few similar cases reported. Remarkably, despite the coexistence of plural effusion and pneumothorax, the patient did not experience dyspnea. The examination also revealed tumor rupture and disruption of the pleura. Considering the possibility of MPM in patients with asymptomatic hydropneumothorax is essential for early diagnosis and appropriate management.

Molecular comparison of concurrent components of high-grade dysplasia, adenocarcinoma, and sarcomatoid carcinoma in a case of sarcomatoid carcinoma of the gallbladder.

Detailed genetic and immunohistochemical features of a sarcomatoid carcinoma of the gallbladder were reported. Studied was a resected gallbladder tumor involving the transverse colon, which was consisted of 3 histopathological neoplastic components, i.e., high-grade dysplasia, adenocarcinoma, and sarcomatoid carcinoma. The targeted amplicon sequencing showed somatic mutations in TP53 (p.S90fs) and ARID1A (c.4993 + 1G > T) in all of the 3 components. Copy numbers of CDKN2A and SMAD4 were decreased in the adenocarcinoma and the sarcomatoid component. Immunohistochemistry showed loss of expression of p53 and ARID1A in all components. p16 expression was lost in the adenocarcinoma and the sarcomatoid component, while SMAD4 expression was lost only in the latter. These results suggest that this sarcomatoid carcinoma may have developed by progression from high-grade dysplasia via adenocarcinoma with sequential accumulation of molecular aberrations involving p53, ARID1A, p16, and SMAD4. This information should serve to understand the molecular mechanism of this very intractable tumor.

In situ expression of the CCL20-CCR6 axis in lymphocyte-rich gastric cancer and its potential role in the formation of lymphoid stroma.

Lymphocyte-rich gastric cancer (Ly-rich GC) is characterized by lymphoid stroma. To understand its formation, we studied the expression of a chemokine ligand (CCL)20 and its receptor CCR6 in 36 and 37 cases of Ly-rich- and conventional GC, respectively. Lymphoid tissues in the alimentary tract were studied in parallel. By quantitative polymerase chain reaction, Ly-rich GC contained CCL20 and CCR6 mRNAs at higher levels than conventional GC. By immunohistochemistry, CCL20 was expressed by cancer cells more frequently in Ly-rich GC than in conventional GC. This was comparable with its expression in epithelial cells of the alimentary tract lymphoid tissues. CCR6 was mostly expressed by dendritic cells (DC) and B cells in Ly-rich GC, which was also comparable with its expression in the alimentary tract lymphoid tissues. Cancer cells also expressed CCR6. However, its expression did not differ between Ly-rich- and conventional GC, nor was it related to the stage of cancer. Given that the CCL20-CCR6 axis is involved in the formation of alimentary tract lymphoid tissue, the similarity between the lymphoid stroma of Ly-rich GC and the alimentary tract lymphoid tissues supports the notion that it plays a significant role in the formation of lymphoid stroma in Ly-rich GC.

Autoimmune pancreatitis and biliary intraepithelial neoplasia of the common bile duct: a case with diagnostically challenging but pathogenetically significant association.

Autoimmune pancreatitis (AIP) (also called IgG4-related sclerosing pancreatitis (IgG4-SP)) and IgG4-related sclerosing cholangitis (IgG4-SC) are frequently associated with each other. It is generally believed that association of these diseases with pancreatobiliary malignancy is, however, rare. Here, we report on the case of a patient with AIP whose biliary cytology revealed severely atypical cells. Surgically resected specimens from this patient showed typical AIP with IgG4-SC, as well as a mildly elevated lesion in the common bile duct with varying degrees of cellular atypia. In addition, the atypical cells tested positive for the mucin-core protein, MUC5AC and p53 overexpression. These findings led us to diagnose the common bile duct lesion as biliary intraepithelial neoplasia (BilIN, mainly BilIN-1/2). Recently, associations between K-ras mutations and pancreatobiliary carcinoma have been reported in patients with AIP. This case, therefore, provides important new insight into the potential association of AIP and/or IgG4-SC with malignancy (or precursor lesions) of the pancreatobiliary system.