Withdrawal of immunosuppression in liver transplantation and the mechanism of tolerance

Comparison of the characteristics of adult liver transplant recipients with prope (almost) tolerance and full immunosuppression regimen

BACKGROUND

The liver transplant recipients are often subjected to excessive therapy by immunosuppressive drugs which produce several complications. Consequently, the minimization or even withdrawal of immunosuppression in selected patients is an attractive alternative. We investigated the frequency and characteristics of these near (or prope from Latin) tolerance in liver transplant recipients in Shiraz Organ Transplant Center.

MATERIAL AND METHODS

We reviewed the medical records of over 3800 adult liver transplant recipients to select a group treated with a low-dose tacrolimus monotherapy (n = 90) between 1994 and 2017 in our transplant center. The patients with the best liver function parameters were selected; then, the clinician arbitrarily decided to withdraw steroids first and then mycophenolate mofetil and maintain each patient on a low dose tacrolimus. We compared the characteristics of prope tolerant recipients on a low-dose tacrolimus with those on standard immunosuppression, namely full-dose tacrolimus plus steroids and mycophenolate mofetil (n = 233). Data were analyzed by t-test, chi-square test using SPSS software version 16.

RESULTS

Out of over 3800 liver transplant patients, 90 (2.34%) recipients were treated with a minimum dose of tacrolimus monotherapy. These recipients were compared to a selected group of 233 (6.1%) recipients treated with full-dose tacrolimus plus steroids and mycophenolate mofetil. In a prope tolerant group, there were 55 males (61.1%) and 35 females (38.9%) recipients. Mean age at the time of transplant was 39.92 ± (SD = 13.40) years with an average time from the transplantation time to completed weaning from triple immunosuppression to low-dose monotherapy of 41.35 months (SD = 17.27). The most common etiology of liver disease among both groups was viral hepatitis.

CONCLUSION

The achievement of prope (almost) immune tolerance was possible only in some liver transplant recipients with a relatively low risk of rejection. Our analysis suggests that there is a difference in the underlying diseases and recipients' age and the number of rejections between the two groups.

Thoracic vertebral metastasis from progressive hepatocellular carcinoma following liver transplantation combined with resection of mesenteric and colonic metastases: A case report

RATIONALE

Surgical treatment of spinal hepatocellular carcinoma metastasis after Liver transplantation (LT) is a clinical challenge. We herein report the clinical outcomes of the first case of a patient with T11 from hepatocellular carcinoma metastasis after systemic chemotherapy following LT combined with mesenteric resection and colectomy, who was successfully treated with En Bloc spondylectomy.

PATIENT CONCERNS

The patient with HCC was a 40-year-old man, who had received LT combined with mesenteric resection and colectomy 15 months before. His main symptom was progressive back pain because of T11 metastasis. PET examinations showed a solitary metastasis at T11 without recurrence in the liver and metastasis in the other organs.

DIAGNOSIS

The patient was diagnosed with the T11 vertebra HCC metastasis after LT combined with resection of HCC mesenteric metastasis and colon metastasis.

INTERVENTIONS

Five cycles of systemic chemotherapy following LT were performed for preventing HCC metastases. However, the right abdominal wall metastasis was found 9 months after LT, followed by T11 metastases thereafter. Immediate resection of the right abdominal wall metastasis was achieved. En Bloc spondylectomy of T11 vertebra was chosen as a treatment for metastasis to T11. After T11 surgery, the patient showed obvious pain relief. However, At 3 months after T11 surgery, a grafted liver metastasis and multiple nodules metastasis in the greater omentum region were revealed with CT imaging, At 5 months after T11 surgery, multiple lung metastases were discovered by MRI. The patient was performed 5 cycles of chemotherapy, 3 times of infusion of iodine [131I] meximab and 3 times of TACE after T11 surgery. Multiple bone metastases were treated with radiotherapy.

OUTCOMES

The patient died 29 months after LT combined with mesenteric resection and colectomy because of recurrence in the liver and metastasis in the lung.

LESSONS

En Bloc spondylectomy may be a therapeutic choice for patients with progression after systemic chemotherapy for the solitary spinal metastases after LT combined with mesenteric resection and colectomy, which has a survival benefit without local recurrence at the surgical site. immunosuppressant after LT may result in worse immune function, which leads to HCC more prone to recurrence and bone metastasis.

En Bloc lumpectomy of T12 vertebra for progressive hepatocellular carcinoma metastases following liver transplantation: A case report

RATIONALE

Liver transplantation (LT) is the preferred surgical option for the treatment of early hepatocellular carcinoma (HCC). In contrast, surgical treatment of progressive HCC metastasized to the spine following LT constitutes a considerable challenge. Here, we report the first case of progressive HCC metastasized to the T12 vertebra after local radiotherapy, treated successfully with en bloc lumpectomy following LT for HCC.

PATIENT CONCERNS

A 40-year-old man who had undergone LT for the treatment of HCC 2 months prior presented to our clinic with symptoms of progressive back pain. Magnetic resonance imagining (MRI) and positron emission tomography (PET) examinations showed a solitary metastasis at T12 without recurrence in the liver or metastasis to other organs.

DIAGNOSES

The patient was diagnosed with HCC metastasized to the T12 vertebra after liver transplantation.

INTERVENTIONS

Local radiation therapy of the T12 vertebra was performed; however, the lesion continued to grow one month after irradiation. Accordingly, the patient was treated with en bloc lumpectomy of the T12 vertebra. After surgery, the patient reported significant pain relief. At 11 months post-surgery, a C4 metastasis with spinal cord compression was revealed by MRI. Multiple grafted liver metastases were also detected by ultrasound along with several lung metastases, which were discovered by X-ray. The patient was treated with a pedicle screw system and a mesh cage filled with frozen autografts for C4 metastasis.

OUTCOMES

The patient died 15 months after liver transplantation due to recurrence in the liver and metastasis to the lung.

LESSONS

En bloc lumpectomy may be a viable therapeutic option for patients with progressive solitary spinal metastases after LT refractory to radiotherapy. Use of immunosuppressive therapy after LT may significantly inhibit immune function, making patients more susceptible to HCC recurrence and bone metastasis.

Mechanisms of liver-induced tolerance

PURPOSE OF REVIEW

To highlight the results of the ongoing research on the mechanisms of liver-induced tolerance focusing on results from the last year.

RECENT FINDINGS

The liver is exposed to a massive antigenic burden of dietary and commensal products from the gastrointestinal tract via portal vein, most of which are necessary for survival. To prevent the immune system from destroying these foreign yet beneficial elements, the liver has developed unique mechanisms to suppress immune responses. It is thought that these mechanisms of acquired tolerance may also underlie the spontaneous acceptance of liver allografts observed after transplantation in many species. The fact that isolated hepatocyte transplants are acutely rejected, suggests that nonparenchymal liver cells play a critical role in spontaneous liver allograft acceptance. IFN-γ, a key inflammatory cytokine produced by T effector (Tef) cells, is paradoxically compulsory for spontaneous liver allograft acceptance. Analysis of IFN-γ signaling points to liver mesenchymal nonparenchymal liver cell that eliminate infiltrating Tef cells via expression of B7-H1, IL-10, and tumor growth factor-β, as well as the enhancement of Tregs and MDSCs. Thus, liver mesenchymal cells are thought to promote tolerance by eliminating alloreactive Tef cells and enhancing suppressor cells (T and B).

SUMMARY

The research during last year offered some key insights into the mechanisms of liver-induced tolerance. Through interactions with activated T cells and B cells via IFN-γ/B7-H1 pathways, liver mesenchymal cells have been shown to be critical components of liver-specific tolerance induction.

Bone metastases from hepatocellular carcinoma: clinical features and prognostic factors

BACKGROUND

Bone metastases (BMs) from hepatocellular carcinoma (HCC) is an increasingly common disease in Asia. We assessed the clinical features, prognostic factors, and differences in outcomes related to BMs among patients with different treatments for HCC.

METHODS

Forty-three consecutive patients who were diagnosed with BMs from HCC between January 2010 and December 2014 were retrospectively enrolled. The clinical features were identified, the impacts of prognostic factors on survival were statistically analyzed, and clinical data were compared.

RESULTS

The median patient age was 54 years; 38 patients were male and 5 female. The most common site for BMs was the trunk (69.3%). BMs with extension to the soft tissue were found in 14 patients (32.5%). Most (90.7%) of the lesions were mixed osteolytic and osteoblastic, and most (69.8%) patients presented with multiple BMs. The median survival after BMs diagnosis was 11 months. In multivariate analyses, survival after BM diagnosis was correlated with Karnofsky performance status (P=0.008) and the Child-Pugh classification (P<0.001); BM-free survival was correlated with progression beyond the University of California San Francisco criteria (P<0.001) and treatment of primary tumors (P<0.001). BMs with extension to soft tissue were less common in liver transplantation patients. During metastasis, the control of intrahepatic tumors was improved in liver transplantation and hepatectomy patients, compared to conservatively treated patients.

CONCLUSIONS

The independent prognostic factors of survival after diagnosis of BMs were the Karnofsky performance status and Child-Pugh classification. HCC patients developed BMs may also benefit from liver transplantation or hepatectomy.