Morten Hagness

Liver transplantation for nonresectable liver metastases from colorectal cancer.

Objective:The objective of this pilot study was to investigate the potential for long-term overall survival (OS) after liver transplantation for colorectal liver metastases (CLMs). Background:Patients with nonresectable CLMs have poor prognosis, and few survive beyond 5 years. CLMs are currently considered an absolute contraindication for liver transplantation, although liver transplantation for primary and some secondary liver malignancies shows excellent outcome in selected patients. Before 1995, several liver transplantations for CLMs were performed, but outcome was poor (5-year survival rate: 18%) and liver transplantation for CLMs was abandoned. Since then, the survival rate after liver transplantation in general has improved by almost 30%. On the basis of this, a 5-year survival rate of about 50% after liver transplantation for CLMs could be anticipated. Methods:In a prospective pilot study, liver transplantation for nonresectable CLMs was performed (n = 21). Main inclusion criteria were liver-only CLMs, excised primary tumors, and at least 6 weeks of chemotherapy. Results:Kaplan-Meier estimates of the OS rate at 1, 3, and 5 years were 95%, 68%, and 60%, respectively. Metastatic recurrence of disease was common (mainly pulmonary). However, a significant proportion of the recurrences were accessible for surgery, and at follow-up (after median of 27 months; range, 8–60), 33% had no evidence of disease. Hepatic tumor load before liver transplantation, time from primary surgery to liver transplantation, and progressive disease on chemotherapy were identified as significant prognostic factors. Conclusions:OS exceeds by far reported outcome for chemotherapy, which is the only treatment option available for this patient group. Furthermore, OS is comparable with liver resection for resectable CLMs and survival after repeat liver transplantation for nonmalignant diseases. Selection strategies based on prognostic factors may further improve the outcome (ClinicalTrials.gov: NCT01311453).

Chemotherapy or Liver Transplantation for Nonresectable Liver Metastases from Colorectal Cancer

OBJECTIVE The primary objective was to compare overall survival (OS) in patients with colorectal cancer (CRC) with nonresectable liver-only metastases treated by liver transplantation or chemotherapy. BACKGROUND CRC is the third most common cancer worldwide. About 50% of patients will develop metastatic disease primarily to the liver and the lung. The majority of patients with liver metastases receive palliative chemotherapy, with a median OS of trial patients of about 2 years, and less than 10% are alive at 5 years. METHODS Patients with nonresectable liver-only CRC metastases underwent liver transplantation in the SECA study (n = 21). Disease-free survival (DFS) and OS of patients included in the SECA study were compared with progression-free survival (PFS) and OS in a similar cohort of CRC patients with liver-only disease included in a first-line chemotherapy study, the NORDIC VII study (n = 47). PFS/DFS and OS were estimated by the Kaplan-Meier method. RESULTS DFS/PFS in both groups were 8 to 10 months. However, a dramatic difference in OS was observed. The 5-year OS rate was 56% in patients undergoing liver transplantation compared with 9% in patients starting first-line chemotherapy. The reason for the large difference in OS despite similar DFS/PFS is likely different metastatic patterns at relapse/progression. Relapse in the liver transplantation group was often detected as small, slowly growing lung metastases, whereas progression of nonresectable liver metastases was observed in the chemotherapy group. CONCLUSIONS Compared with chemotherapy, liver transplantation resulted in a marked increased OS in CRC patients with nonresectable liver-only metastases.

A Novel Concept for Partial Liver Transplantation in Nonresectable Colorectal Liver Metastases: The RAPID Concept.

OBJECTIVE Selected patients with nonresectable colorectal liver metastases benefit from liver transplantation and have acceptable 5-year survival rates. However, allocating full-sized grafts to this group of patients is difficult due to the scarcity of grafts. This could be improved by utilizing small partial grafts, which mandates effective strategies to overcome the problems regarding insufficient functional liver mass. METHODS We have developed a protocol incorporating previously reported experiences from living donor transplantation and recent developments in liver surgery, facilitating transplantation of very small liver grafts. At the time of transplantation, segments 1 to 3 are resected in the recipient and orthotopically replaced by a segment 2 to 3 allograft. Portal inflow is modulated by redirecting the portal flow to the graft with concomitant focus on keeping the portal vein pressure below 20 mm Hg. A second-stage hepatectomy is performed as soon as the graft has regenerated to a sufficient volume. RESULTS A graft weighing 330 g was transplanted to a 50-year-old man weighing 92 kg, and the portal vein to the right remnant liver was closed. The volume of the liver graft was doubled 2 weeks after the first procedure, and it increased further after the second procedure, with extended right hepatectomy performed at day 23 after transplantation. There were no signs of liver failure or small-for-size syndrome. CONCLUSIONS The current protocol and ongoing study could represent a possible strategy to increase the availability of liver transplantation to patients with nonresectable liver tumors such as hepatocellular carcinoma and colorectal liver metastases.

Kinetics and Activation Requirements of Contact-Dependent Immune Suppression by Human Regulatory T Cells

Naturally occurring regulatory T cells (Tregs) maintain self tolerance by dominant suppression of potentially self-reactive T cells in peripheral tissues. However, the activation requirements, the temporal aspects of the suppressive activity, and mode of action of human Tregs are subjects of controversy. In this study, we show that Tregs display significant variability in the suppressive activity ex vivo as 54% of healthy blood donors examined had fully suppressive Tregs spontaneously, whereas in the remaining donors, anti-CD3/CD2/CD28 stimulation was required for Treg suppressive activity. Furthermore, anti-CD3/CD2/CD28 stimulation for 6 h and subsequent fixation in paraformaldehyde rendered the Tregs fully suppressive in all donors. The fixation-resistant suppressive activity of Tregs operated in a contact-dependent manner that was not dependent on APCs, but could be fully obliterated by trypsin treatment, indicating that a cell surface protein is directly involved. By add-back of active, fixed Tregs at different time points after activation of responding T cells, the responder cells were susceptible to Treg-mediated immune suppression up to 24 h after stimulation. This defines a time window in which effector T cells are susceptible to Treg-mediated immune suppression. Lastly, we examined the effect of a set of signaling inhibitors that perturb effector T cell activation and found that none of the examined inhibitors affected Treg activation, indicating pathway redundancy or that Treg activation proceeds by signaling mechanisms distinct from those of effector T cells.

Regulatory T cells that co-express RORγt and FOXP3 are pro-inflammatory and immunosuppressive and expand in human pancreatic cancer

ABSTRACT Pancreatic ductal adenocarcinoma (PDAC) is highly infiltrated by CD4+T cells that express RORγt and IL-17 (TH17). Compelling evidence from the tumor microenvironment suggest that regulatory T cells (Treg) contribute to TH17 mediated inflammation. Concurrently, PDAC patients have elevated levels of pro-inflammatory cytokines that may lead to TH17 associated functional plasticity in Treg. In this study, we investigated the phenotype and functional properties of Treg in patients with PDAC. We report that PDAC patients have elevated frequency of FOXP3+Treg, which exclusively occurred within the FOXP3+RORγt+Treg compartment. The FOXP3+RORγt+Treg retained FOXP3+Treg markers and represented an activated subset. The expression of RORγt in Treg may indicate a phenotypic switch toward TH17 cells. However, the FOXP3+RORγt+Treg produced both TH17 and TH2 associated pro-inflammatory cytokines, which corresponded with elevated TH17 and TH2 immune responses in PDAC patients. Both the FOXP3+Treg and FOXP3+RORγt+Treg from PDAC patients strongly suppressed T cell immune responses, but they had impaired anti-inflammatory properties. We conclude that FOXP3+RORγt+Treg have a dual phenotype with combined pro-inflammatory and immunosuppressive activity, which may be involved in the pathogenesis of PDAC.

Human regulatory T cells control TCR signaling and susceptibility to suppression in CD4+ T cells.

Human CD4+CD25hiFOXP3+ regulatory T cells maintain immunologic tolerance and prevent autoimmune and inflammatory immune responses. Regulatory T cells undergo a similar activation cycle as conventional CD4+ T cells upon antigen stimulation. Here, we demonstrate that T cell receptors and costimulation are required to activate the regulatory T cell suppressive function. Regulatory T cells suppressed the T cell receptor signaling in effector T cells in a time‐dependent manner that corresponded with inhibition of cytokine production and proliferation. Modulation of the activation level and thereby the suppressive capacity of regulatory T cells imposed distinct T cell receptor signaling signatures and hyporesponsiveness in suppressed and proliferating effector T cells and established a threshold for effector T cell proliferation. The immune suppression of effector T cells was completely reversible upon removal of regulatory T cells. However, the strength of prior immune suppression by regulatory T cells and corresponding T cell receptor signaling in effector T cells determined the susceptibility to suppression upon later reexposure to regulatory T cells. These findings demonstrate how the strength of the regulatory T cell suppressive function determines intracellular signaling, immune responsiveness, and the later susceptibility of effector T cells to immune suppression and contribute to unveiling the complex interactions between regulatory T cells and effector T cells.

Survival following liver transplantation for liver-only colorectal metastases compared with hepatocellular carcinoma

Liver transplantation is considered the standard of care for patients with hepatocellular carcinoma (HCC) within the Milan criteria. Liver transplantation in patients with unresectable colorectal cancer with liver‐only disease has been shown to be associated with a 5‐year overall survival rate of 56 per cent, compared with 9 per cent in patients receiving standard palliative chemotherapy. The aim of the present study was to compare disease‐free (DFS) and overall (OS) survival after liver transplantation in patients with HCC and those with colorectal metastases.

Liver transplantation in treatment of colorectal liver metastases

Surgical resection is the only curative modality for colorectal liver metastases (CLM) and 5-year overall survival after resection is about 40%. Nonresectable CLM is not curable and 5-year overall survival is currently about 10%. Before 1995, several liver transplantations for CLMs were performed, but outcome was poor (5-year survival rate: 18%). Liver transplantation for CLMs was abandoned and CLMs were even considered a contraindication to the procedure. Since then, the survival rate after liver transplantation in general has improved by almost 30%. In a prospective pilot study of liver transplantation for nonresectable CLM, a 5-year overall survival rate of 60% was demonstrated, however 19 of 21 patients experienced recurrence of disease. Here, current knowledge and ongoing research in this field is reviewed, and the potential role for liver transplantation as one of several treatment modalities for CLM discussed.

Donor-derived strongyloidiasis after organ transplantation in Norway

Strongyloides stercoralis is an intestinal helminth which in humans can cause asymptomatic chronic infection maintained for decades through its auto‐infective cycle. During solid organ transplantation, recipients may unintentionally receive an organ infected with strongyloides. This is a very rare complication but may have deadly outcome if not detected. We hereby report two transplant recipients whom developed Strongyloides hyperinfection syndrome after organ transplantation from the same deceased donor. Recipient 1 was kidney transplanted and presented at day 65 post engraftment with diarrhea and subsequent septicemia and gastric retention. Larvae were detected in gastric aspirate. Recipient 2 was simultaneously kidney and pancreas transplanted and presented at day 90 post engraftment also with gastric retention and septicemia. Larvae were demonstrated on duodenal biopsy and stool sample. The clinical course was complicated with severe duodenal bleedings, gastric retention, meningitis, and prolonged hospitalization. Retrospective testing of pre‐transplant donor serum was positive for Strongyloides stercoralis antibodies. As a result of disease severity and gastric retention albenazole was administered via a jejunal tube and ivermectin subcutaneously in both recipients. S stercoralis was successfully eradicated and the transplants ended up with unaffected graft function. Following these two cases, we started systematic screening of all deceased donors for serum Strongyloides IgG in October 2016. After having screened 150 utilized donors one tested positive for Strongyloides, which initiated prophylactic ivermectin treatment to organ recipients. No symptoms or disease developed. Our center will continue to screen all donors as prophylactic treatment may avert this potentially lethal complication in cases of donor‐derived Strongyloides infection.

The Potential Role of Liver Transplantation as a Treatment Option in Colorectal Liver Metastases

Liver resection is the only potentially curative treatment option in patients with liver metastases from colorectal cancer, but only about 20% of the patients are resectable. Liver transplantation of patients with unresectable liver metastases was attempted in the early era but it was abandoned due to poor survival. During the last decade, several case reports, a controlled pilot study, and a retrospective cohort study indicated that prolonged disease-free survival and overall survival can be obtained in a proportion of these patients. Strict selection criteria have not yet been well defined, but tumor load, response to chemotherapy, pretransplant carcinoembryonic antigen level, and time interval from resection of the primary tumor to transplant are all factors related to outcome. Carefully selected patients may obtain 5-year overall survival that approaches conventional indications for liver transplant. The scarcity of liver grafts is a significant problem, but this can possibly to some extent be addressed by use of extended criteria grafts and novel surgical techniques. There is an increasing interest in liver transplantation in these patients in the transplant community, and currently 4 clinical trials are active and are recruiting.