Sachiko Minamiguchi

Impact of recipient age on outcome of ABO-incompatible living-donor liver transplantation.

Background. Transplantation of hepatic grafts from ABO-incompatible donors is controversial because of the risk of hyperacute rejection mediated by preformed anti-ABO antibodies. The aim of the present study was to evaluate the outcome of liver transplants performed with ABO-incompatible living-donor livers and to detect risk factors for development of complications. Methods. From June 1990 to February 2000, 66 patients, 10 months to 55 years old (median, 2 years old), received 68 ABO-incompatible living-donor liver grafts. The antibody titer and clinical course were followed prospectively during a period ranging from 3 to 11 years. Results. The 5-year patient survival was 59%, 76%, and 80% for ABO-incompatible, ABO-compatible, and ABO-identical grafts, respectively (P <0.01). In patients <1 year old, ≥1 to <8, ≥8 to <16, and and ≥16 years old, 5-year survival was 76%, 68%, 53%, and 22%, respectively. The incidence of intrahepatic biliary complications and hepatic necrosis in ABO-incompatible living-related grafts (18% and 8%, respectively) was significantly (P <0.0001) greater than in ABO-compatible and ABO-identical grafts (both 0.6% and 0%, respectively). Predictive risk factors for increased mortality and morbidity were age greater than 1 year and elevated anti-ABO titers before transplantation. Conclusions. ABO-incompatible liver transplantation was carried out with relative safety in infants <1 year old but was not satisfactory in children >1 year in long-term follow-up. Patients aged >8 years remain at considerable risk of early fatal outcome because of hepatic necrosis, and new strategies to prevent antibody-mediated rejection are required.

Noninvasive evaluation of graft steatosis in living donor liver transplantation

Background. Hepatic steatosis affects graft function as well as postoperative recovery of donors in living donor liver transplantation. Liver macrovesicular steatosis in living donors was assessed using quantitative X-ray computed tomography (CT) analysis and histological examination of intraoperative liver biopsy. Methods. A total of 266 living donors with complete pretransplant CT data and intraoperative “time 0” biopsy were included in the study. Liver biopsy specimen obtained during donor operation was examined for macrovesicular steatosis and was classified as none; mild (<30%); moderate (30%–60%); or severe (>60%). Liver-to-spleen CT attenuation values ratio (L/S ratio) on noncontrast-CT was evaluated for its usefulness as an index of hepatic steatosis in comparison with other parameters including body mass index (BMI) and serum liver function tests (gamma-glutamyl transpeptidase, alanine aminotransferase, aspartate aminotransferase, cholinesterase, and total cholesterol) using receiver operating characteristic (ROC) analysis. Results. Histological grade of macrovesicular steatosis was none in 198 patients (74.4%), mild in 50 (18.8%), moderate in 15 (5.7%), and severe in 3 (1.1%). The median L/S ratios for the respective histological grades were 1.20 (range: 1.00–1.46), 1.12 (0.83–1.37), 1.01 (0.74–1.21), and 0.90 (0.70–0.99) (P<0.0001). The ROC curve for L/S ratio was located closest to the upper left corner, and the area under the curve of L/S ratio was significantly larger than that of any other preoperative variables. Conclusion. L/S ratio calculated from preoperative CT can be a useful tool to discriminate hepatic macrovesicular steatosis. Based on the present results, the optimal cut-off value for L/S ratio to exclude more than moderate steatosis would be 1.1.

Interobserver and intraobserver variability in the diagnosis of hydatidiform mole.

Surgical pathologists often encounter hydropic villi in products of conception at the first trimester and must determine whether the villi represent complete hydatidiform mole (CM), partial hydatidiform mole (PM), or hydropic abortion (HA). The distinction between these is important for determining the appropriate treatment of patients. This study assessed interobserver and intraobserver variability in the histologic diagnosis of hydatidiform mole among 5 placental pathologists. To evaluate interobserver variability, one representative slide from each of 50 mixed cases of PM, CM, and HA of the first trimester were circulated among 5 placental pathologists. All pathologists used the same histologic criteria by Szulman and Surti. For the second round, the same cases were submitted with DNA ploidy data. For the third round, the slides were recoded and distributed to assess intraobserver agreement. Kappa (κ) value was calculated for the interobserver agreement in the first and second rounds. There was agreement among 4 or 5 pathologists for only 30 of 50 cases in the first round. There were problems in differentiating between PM and HA in most of the remaining 20 cases. The κ values varied from poor (κ = −0.104) to excellent (κ = 0.761) in the first round. In the second round, there was agreement in 39 of 50 cases and the level of agreement remarkably increased, ranging from fair to good (κ = 0.552) to excellent (κ = 0.851). The number of discrepant cases, PM versus HA, was reduced to 4. In 7 cases, there were difficulties in distinguishing CM from HA. The intraobserver agreement ranged from 50% to 90%. Poor interobserver agreement was demonstrated when histology alone was used for diagnosis. Discordance was most frequently seen in PM versus HA and resulted from difficulty in evaluating trophoblastic hyperplasia. Polar trophoblastic growth seen in HA could also be observed in PM. The addition of ploidy data resulted in a significant improvement in concordance. Ploidy study is useful in equivocal cases. Significant interobserver and intraobserver variability was observed even among placental pathologists. New histologic criteria adaptable to differentiation of early lesions are needed.

Progressive graft fibrosis and donor‐specific human leukocyte antigen antibodies in pediatric late liver allografts

The role of donor‐specific anti‐human leukocyte antigen antibodies (DSAs) that develop late after living donor liver transplantation is unknown. Seventy‐nine pediatric recipients who had good graft function and underwent protocol liver biopsy more than 5 years after transplantation (median = 11 years, range = 5‐20 years) were reviewed. DSAs were determined with the Luminex single‐antigen bead assay at the time of the last biopsy, and complement component 4d (C4d) immunostaining was assessed at the times of the last biopsy and the previous biopsy. The donor specificity of antibodies could be identified in 67 patients: DSAs were detected in 32 patients (48%), and they were usually against human leukocyte antigen class II (30 cases) but were rarely against class I (2 cases). These patients had a higher frequency of bridging fibrosis or cirrhosis (28/32 or 88%) than DSA‐negative patients (6/35 or 17%, P < 0.001). Fibrosis was likely to be centrilobular‐based. DSA‐positive patients, in comparison with DSA‐negative patients, had higher frequencies of diffuse/focal endothelial C4d staining (P < 0.001) and mild/indeterminate acute rejection [15/32 (47%) versus 5/35 (14%), P = 0.004]. Four DSA‐negative patients were off immunosuppression, whereas no patients in the DSA‐positive group were (P = 0.048). In conclusion, the high prevalence of graft fibrosis and anti–class II DSAs in late protocol biopsy samples suggests that humoral alloreactivity may contribute to the process of unexplained graft fibrosis late after liver transplantation. Liver Transpl 18:1333–1342, 2012.

Outcome and risk factors of de novo autoimmune hepatitis in living-donor liver transplantation.

Background. Graft dysfunction mimicking autoimmune hepatitis (AIH) develops only rarely after liver transplantation for nonautoimmune liver disease. The long-term prognosis and risk factors of de novo AIH after living-donor liver transplantation (LDLT) are unknown. Methods. We review our LDLT series to investigate the incidence and outcome of this form of graft dysfunction, focusing on follow-up histology. Results. Of 633 patients who underwent LDLT at Kyoto University from 1990 to 2002, 13 (2.1%) developed graft dysfunction with interface hepatitis resembling AIH (2 males, 11 females). The median age at LDLT of these 13 patients was 10 years (8 months to 26 years). All received tacrolimus-based immunosuppression. The dysfunction presented at a median interval of 3.1 (0.7–9.5) years after LDLT. Nine had definite AIH, and four had probable AIH at the onset of hepatitis. Patients were followed after a median of 3.5 (0.1–8) years from the onset of de novo AIH. Of 11 patients who underwent follow-up histologic evaluation, 3 underwent retransplantation, and 8 continued to have similar findings on subsequent biopsies, with fluctuations in the amount of necroinflammatory activity and an increase in fibrosis despite treatment. In a multivariate analysis, acute rejection episodes and recipient age between 11 and 15 years at LDLT independently had predictive value for the development of de novo AIH. Human leukocyte antigen-A, B, and DR mismatches and sex mismatch did not influence the occurrence of de novo AIH. Conclusion. This series highlights the more severe histologic outcome of de novo AIH with longer follow-up despite immunosuppressive treatment. De novo AIH may arise from alloimmunologic injury, marked by clinically obvious episodes of acute rejection.

Periportal edema and necrosis as diagnostic histological features of early humoral rejection in ABO‐incompatible liver transplantation

Humoral rejection caused by antidonor blood group A/B antibodies is one of the most important obstacles for successful ABO‐incompatible liver transplantation. However, no specific morphologic features of liver biopsies to distinguish humoral rejection from other conditions such as ischemia or sepsis have been satisfactorily documented. To histologically clarify the early changes in humoral rejection, we studied 41 cases of living donor ABO‐incompatible liver transplantation whose allograft biopsies during the first episode of suspected acute rejection were available within the first postoperative month. Postoperative isohemagglutinin IgM titers were ×64 or more in 21 patients (51%; high‐titer group) and less than ×64 in 20 cases (49%; low‐titer group). In the high‐titer group, elevation of postoperative titers ×64 or more occurred within postoperative days 5.7 ± 4.1 (range: 1–17). An increase in the incidence of cholangitis was observed in the high‐titer group (90% vs. 30%, P < .0001), as well as poorer overall graft survival than in the low‐titer group (38% vs. 70%, P < .05). Seven biopsies obtained from the high‐titer group within 3 days after the onset of elevation of the antibody titers and one biopsy obtained at the peak of the antibody titers demonstrated periportal edema and necrosis, neither of which was found in the low‐titer group. All grafts of these patients caused massive hepatocyte necrosis or severe biliary complications. In conclusion, a high morbidity rate of ABO‐incompatible liver transplantation is associated with high postoperative levels of antibody titers. Periportal edema and necrosis observed during elevation of antibody titers can be regarded as histological indications of early changes in severe humoral rejection. (Liver Transpl 2004;10:16–27.)

Living related liver transplantation: Histopathologic analysis of graft dysfunction in 304 patients

Between June 1990 and August 1997, 304 mainly pediatric patients underwent a total of 311 orthotopic living related liver transplantations (LRLTs) under tacrolimus immunosuppression at Kyoto University Hospital. Congenital biliary atresia was the most common underlying disease. The donor was a parent, and the left lateral segments were used as grafts in most cases. The average number of loci of HLA-A, -B, and -DR mismatches between the donor and the recipient were 2.1. Forty-three transplants were ABO-incompatible. Liver histology at the time of abnormal liver function after transplantation was analyzed. Preservation injury was rare and mild. Acute cellular rejection (ACR) occurred in 36% of transplants during the first 6 months. Average rejection activity index (the Banff schema) was 4.2 and severe rejection was rarely seen. The number of mismatching HLA loci and immunosuppression regimens affected the incidence of ACR. Chronic rejection (CR) occurred in 2% of transplants. Concerning humoral rejection, no hyperacute rejection was seen. However, hepatic artery thrombosis (delayed hyperacute rejection) was seen in an ABO-incompatible transplant. Acute hepatitis, including those related to cytomegalovirus and Epstein-Barr virus, occurred in 17% of transplants. Chronic hepatitis, including hepatitis B and C, developed in 3%. Acute or chronic cholangitis occurred in 16%, and a significantly higher incidence of cholangitis was found in ABO-incompatible transplants. Posttransplantation lymphoproliferative disease developed in 2%. In LRLT, milder preservation injury and less frequent ACR and CR were suggested, probably because of the short cold-ischemia time and the advantages of HLA histocompatibility, respectively.

Loss of SMAD4 Promotes Colorectal Cancer Progression by Accumulation of Myeloid-Derived Suppressor Cells through the CCL15–CCR1 Chemokine Axis

Purpose: We previously reported that loss of SMAD4 promotes chemokine CCL15 expression to recruit CCR1+ myeloid cells via the CCL15–CCR1 axis, which facilitates metastasis of colorectal cancer to the liver. The purposes of this study were to investigate whether essentially the same mechanism works in tumor invasion of the primary colorectal cancer and to evaluate the clinical importance of CCL15 expression and CCR1+ cell accumulation. Experimental Design: Using human colorectal cancer cell lines with reduced expression of SMAD4 or CCL15, we investigated tumor growth activities in vivo. We used immunohistochemistry (IHC) to investigate expression of SMAD4, CCL15, and CCR1 with 333 clinical specimens of primary colorectal cancer. We next characterized the CCR1+ cells using double immunofluorescence staining with several specific cell-type markers. Finally, we determined the serum CCL15 levels in 132 colorectal cancer patients. Results: In an orthotopic xenograft model, CCL15 secreted from SMAD4-deficient colorectal cancer cells recruited CCR1+ cells, resulting in aggressive tumor growth. IHC indicated that loss of SMAD4 was significantly associated with CCL15 expression, and that CCL15-positive primary colorectal cancers recruited approximately 2.2 times more numbers of CCR1+ cells at their invasion front than CCL15-negative colorectal cancers. Importantly, these CCR1+ cells were of the myeloid-derived suppressor cell (MDSC) phenotype (CD11b+, CD33+, and HLA-DR−). Most CCR1+ cells showed the granulocytic-MDSC phenotype (CD15+), whereas some showed the monocytic-MDSC phenotype (CD14+). Serum CCL15 levels in colorectal cancer patients were significantly higher than in controls. Conclusions: Blocking the recruitment of CCR1+ MDSCs may represent a novel molecular-targeted therapy, and serum CCL15 concentration can be a novel biomarker for colorectal cancer. Clin Cancer Res; 22(2); 492–501. ©2015 AACR.

Sclerosing peritonitis associated with luteinized thecoma of the ovary

A unique case of bilateral Iuteinized the comas of the ovary associated with sclerosing peritonitis is reported and the clinical and pathological features of this and previously reported cases are reviewed. The patient, 52 years of age, presented with abdominal distension and diarrhea. Pelvic imaging studies revealed bilateral ovarian tumors with ascltes. Total abdominal hysterectomy and bilateral salpingo‐oophorectomy with adhesiotomy of the small bowel were performed. Histologically, the ovarian tumor was composed of closely packed spindle to round‐shaped cells, and within the spindle cell population, lutein‐like cells were scattered singly or in clusters. Mitotic counts of spindle cells revealed 12 mitotic figures (MF) per 10 high‐power fields (HPF) in one part of the left ovarian tumor, but other areas of the tumor showed less than 3 MF/10 HPF on average. The lesion from the resected small bowel showed prominent fibrosis confined to the serosa with no evidence of metastasis from the ovarian tumor. The patient has undergone adhesiotomy with parttal resection of the small bowel seven times since the first laparotomy because of the recurrent small bowel obstruction. The patient has survived with complications due to short bowel syndrome for 7 years after the initial surgery and so far no recurrence or metastasis of the ovarian tumor has been Identified. The case reported here also supports the idea that lutefnlzed thecoma of the ovary associated with sclerosing peritonitis may be a distinct clinicopathologic entity, in terms of the unique association and of the unique features of thecoma; that is, bilateral, hormonally inactive and apparently benign in spite of its highly mitotic activity. Additional attention should be paid to the patients quality of life, which is often degraded by peritoneal flbrosis and small bowel obstruction.

Application of complement component 4d immunohistochemistry to ABO‐compatible and ABO‐incompatible liver transplantation

Antibody‐mediated rejection (AMR) is difficult to diagnose after ABO‐compatible or ABO‐identical (ABO‐C) liver transplantation. To determine whether complement component 4d (C4d) immunostaining would be useful for diagnosing AMR, we compared the results of C4d immunohistochemistry for allograft biopsy samples with assays for anti‐donor antibodies performed at the time of biopsy. One hundred fourteen patients with ABO‐C grafts and 29 patients with ABO‐incompatible (ABO‐I) grafts were included. Linear C4d endothelial staining (identifiable with a 4× objective lens) or staining seen in 50% or more of the portal tracts was considered positive. Five of the 114 patients (4%) with ABO‐C grafts and 15 of the 29 patients (52%) with ABO‐I grafts showed C4d positivity. In the ABO‐C cases, C4d positivity in late biopsy samples (≥30 days after transplantation) was associated with stage 2 or higher fibrosis (METAVIR score; P = 0.01) and with the presence of donor‐specific anti–human leukocyte antigen DR antibodies (HLA‐DR DSAs) with a mean fluorescence intensity > 5000 according to the Luminex single‐antigen bead assay (P = 0.04). Conversely, the presence of HLA‐DR DSAs was associated with the presence of stage 2 or higher fibrosis, acute cellular rejection, and C4d positivity. During the 2‐year follow‐up, neither C4d positivity nor HLA‐DR DSAs were related to graft loss. Among ABO‐I patients, C4d positivity was not associated with allograft dysfunction or fibrosis. Only 3 of the 15 C4d‐positive patients (20%) showed periportal hemorrhagic edema, which could be a histological sign of AMR in ABO‐I grafts, and they were the only cases associated with elevations in anti‐donor A/B antibody titers. In conclusion, C4d endothelial positivity among ABO‐C patients is an uncommon event that could be associated with chronic graft damage with or without clinical AMR. C4d positivity is common among ABO‐I patients and may not be associated with allograft dysfunction if alloantibody titers are not elevated. Liver Transpl 20:200‐209, 2014.