Feasibility and mid- to long-term results of endovascular treatment for portal vein thrombosis after living-donor liver transplantation

PURPOSEWe aimed to evaluate mid- to long-term results of endovascular treatment for portal vein thrombosis (PVT) after living-donor liver transplantation (LDLT).METHODSThirty cases (14 males, 16 females; age range, 0.67–65 years) who underwent endovascular treatment including thrombolysis, angioplasty, stent placement, and/or collateral embolization for PVT after LDLT from 2001 to 2017 were retrospectively reviewed. Clinical and procedural data were collected and analyzed regarding the patency of the PVT site at the last follow-up date (PVT-free persistency) using Log-rank test. Results were considered statistically significant at p < 0.05.RESULTSMedian follow-up was 120 months. The technical success rate was 80% (n=24). Patency rates at 1 week and 1, 3, 6, 12, 36, and 60 months were 73%, 59%, 55%, 51%, 51%, 51%, and 51% for primary patency and 80%, 70%, 66%, 66%, 66%, 61%, and 61% for assisted patency after secondary endovascular treatment. PVT-free persistency rates regarding the subgroups were as follows: children under 12 years vs. adults, 50% vs. 68% (p = 0.42); acute vs. nonacute, 76% vs. 46% (p = 0.10); localized vs. extensive, 90% vs. 50% (p = 0.035); transileocolic approach vs. percutaneous-transhepatic approach, 71% vs. 54% (p = 0.39); and thrombolysis-based treatment vs. non-thrombolysis-based treatment, 71% vs. 44% (p = 0.12), respectively. Among technically successful cases, PVT-free persistency rate was 94% for those with hepatopetal flow in the peripheral portal vein vs. 17% for those without hepatopetal flow (p < 0.001). The only major complication occurring was pleural hemorrhage (n=1). Minor complications (i.e., fever) occurred in 18 patients (60%).CONCLUSIONIn conclusion, mid- to long-term portal patency following endovascular treatment was approximately 50%–60% in PVT patients after LDLT. PVT site patency over three months after the first endovascular treatment, localized PVT, and hepatopetal flow in the peripheral portal vein were identified as key prognostic factors for mid- to long-term portal patency.

Portal vein thrombosis (PVT) is a vascular complication of living-donor liver transplantation (LDLT), with an estimated incidence of up to 4% (1, 2). The risk of vascular complications, including PVT, is higher in LDLT compared with conventional deceased-donor liver transplantation, because of the smaller vessels, insufficient vessel length for reconstruction, neointimal proliferation, and higher risk of twisting and kinking of the vascular pedicle (3) due to smaller graft size than in deceased-donor liver transplantation. PVT after LDLT can lead to graft failure and the need for retransplantation or death (2), making immediate treatment crucial.Endovascular-based treatment is one option for treating PVT. The utility of target-focused thrombolysis, balloon angioplasty, and stent placement to restore portal flow has been reported previously (4–10). However, the efficacy of endovascular treatment after LDLT has only been presented in some case reports (11, 12) and the mid- to long-term outcomes remain unclear.The purpose of this study was to evaluate the technical success, feasibility, and mid- to long-term results of endovascular treatment for PVT after LDLT in our institution.     

Ascending contraction and descending relaxation in the distal colon of mice lacking interstitial cells of Cajal.

Recently an essential role of interstitial cells of Cajal (ICC) within myenteric plexus (ICC-MY) was suggested in ascending contraction and descending relaxation in the mouse ileum. The role of ICC in these neural reflexes was examined in the distal colonic segments prepared from the wild type and c-kit mutant, W/W(V) mice, in the present study. Localized distension of the segments from the wild type mice by using a small balloon resulted in ascending contraction and descending relaxation. In the segments from the mutant mice, localized distension also induced these neural reflexes similar to those observed in the wild type mice. Immunohistochemical examination demonstrated that ICC-MY and ICC present in muscle layers (ICC-IM) were severely disrupted in the mutant mouse, but only ICC, present within submucosal plexus (ICC-SMP), remained unchanged. In the small strips with ICC-SMP absent prepared from the mutant mouse, electrical field stimulation induced contraction or relaxation in the absence or presence of atropine, respectively. It was suggested that ICC have no important role in the ascending and descending neural reflexes in the mouse distal colon, this is in direct contrast to the role of ICC-MY in the ileum.     

Identification of testicular atypical germ cells by an immunohistochemical technique for placental alkaline phosphatase

The identification of atypical testicular germ cells is often difficult by by routine histologic examination. By immunohistochemical detection of placental alkaline phosphatase (PLAP) and by periodic acid Schiff staining of glycogen, atypical germ cells were easily identified in testicular samples. Forty-one fetal and adult testes were used for a preliminary study, and 121 testes from infants and adults with either cryptorchidism or germ cell tumors were studied for the presence of atypical germ cells. Two types of clear germ cells were differentiated histochemically, and one with PLAP-positive cell surfaces and glycogen-rich cytoplasm was considered to be atypical. The alkaline phosphatase of atypical germ cells appeared to be similar to that found in a few germ cells of early fetal testes. The atypical germ cells seemed to be multi-potential malignant cells capable of developing not only into seminoma but also into other germ cell tumors. Only in yolk sac tumor of infants were the atypical germ cells absent from tumor-adjacent seminiferous tubules.     

Regeneration of the hamstring tendons after harvesting for arthroscopic anterior cruciate ligament reconstruction: a histological study in 11 patients

The purpose of our study is to evaluate whether the hamstring tendons can regrow after harvesting for anterior cruciate ligament (ACL) reconstruction and whether the regenerate tissue can be histologically characterized as tendinous. Eleven of the patients (eight female and three male; mean age, 23 years; range 17–37 years) consented to participate in this study. One year after the ACL reconstruction, surgical biopsy was done. Regeneration of the tendon was detected macroscopically in 9 of the 11 patients. Histologically and immunohistochemically, the regenerated tendons closely resembled normal ones. The results of this study show the hamstring tendons can regenerate after harvesting for the ACL reconstruction.     

Sudden death from metastatic esophageal cancer to the ventricular septum.

A 67-year-old man was admitted to our hospital due to esophageal cancer. Cancer existed at the lower esophagus and subtotal esophagectomy and lymphadenectomy was performed. The postoperative course was uneventful. Pathological findings revealed moderately differentiated squamous cell carcinoma that metastasized to the abdominal lymph nodes which include the paraaortic lymph nodes. He complained of anorexia three months after the operation and was found to have multiple liver and mediastinal lymph node metastases. He was admitted for chemotherapy. Before starting chemotherapy, he suddenly died without any sign of hemorrhage or respiratory disorder. Autopsy showed metastatic lesions to the heart and mediastinal lymph nodes, liver, thoracic vertebrae, kidney, adrenal gland and heart. Metastatic nodules in the heart were on the ventricular septum where the conducting system exists. No direct invasion from the pericardium was observed. Blockade of the conducting system of the heart was considered to have caused the severe arrhythmia and sudden cardiac arrest.     

MOLECULAR GENETICS OF THE SA GENE

1. We have recently identified a candidate gene for rat genetic hypertension, termed S_a, by identifying an mRN A species that shows markedly higher expression in the kidneys of spontaneously hypertensive rats (SHR) than in those of Wistar-Kyoto rats (WKY). 2. Subsequent genetic co-segregation analyses by ourselves and others indicated that the S_a gene locus did indeed influence blood pressure. Moreover, in a preliminary association study, we found an association of a polymorphism of the human S_a gene with essential hypertension. 3. Further studies to identify functions of the Sa gene products are required before reaching a definite conclusion.