Immunological Basis of Genesis of Hepatocellular Carcinoma: Unique Challenges and Potential Opportunities through Immunomodulation

A majority of hepatocellular carcinoma (HCC) develops in the setting of persistent chronic inflammation as immunological mechanisms have been shown to play a vital role in the initiation, growth and progression of tumours. The index review has been intended to highlight ongoing immunological changes in the hepatic parenchyma responsible for the genesis and progression of HCC. The in-situ vaccine effect of radiofrequency (RF) is through generation tumour-associated antigens (TAAs), following necrosis and apoptosis of tumour cells, which not only re-activates the antitumour immune response but can also act in synergism with checkpoint inhibitors to generate a superlative effect with intent to treat primary cancer and distant metastasis. An improved understanding of oncogenic responses of immune cells and their integration into signaling pathways of the tumour microenvironment will help in modulating the antitumour immune response. Finally, we analyzed contemporary literature and summarised the recent advances made in the field of targeted immunotherapy involving checkpoint inhibitors along with RF application with the intent to reinstate antitumour immunity and outline future directives in very early and early stages of HCC.

A Systematic Review and Meta-Analysis Comparing Liver Resection with the Rf-Based Device Habib™-4X with the Clamp-Crush Technique

Liver cancer is the sixth most common cancer and third most common cause of cancer-related mortality. Presently, indications for liver resections for liver cancers are widening, but the response is varied owing to the multitude of factors including excess intraoperative bleeding, increased blood transfusion requirement, post-hepatectomy liver failure and morbidity. The advent of the radiofrequency energy-based bipolar device Habib™-4X has made bloodless hepatic resection possible. The radiofrequency-generated coagulative necrosis on normal liver parenchyma provides a firm underpinning for the bloodless liver resection. This meta-analysis was undertaken to analyse the available data on the clinical effectiveness or outcomes of liver resection with Habib™-4X in comparison to the clamp-crush technique. The RF-assisted device Habib™-4X is considered a safe and feasible modality for liver resection compared to the clamp-crush technique owing to the multitude of benefits and mounting clinical evidence supporting its role as a superior liver resection device. The most intriguing advantage of the RF-device is its ability to induce systemic and local immunomodulatory changes that further expand the boundaries of survival outcomes following liver resection.

Case report on the role of radiofrequency-assisted spleen-preserving surgery for splenic metastasis in the era of check-point inhibitors

RATIONALE

An isolated splenic metastasis is a rare phenomenon noted in advanced stage melanoma. We report the role of radiofrequency (RF) -based splenic-preserving splenectomy in a patient with a solitary splenic metastasis from advanced stage melanoma that was managed with checkpoint inhibitors.

PATIENT CONCERNS

We report a case of a 60-year-old man who presented with multiple lung metastases and a solitary splenic metastasis with advanced stage melanoma following excision of primary from his trunk 2.3 years back.

DIAGNOSIS

Considering the diagnosis of advanced stage melanoma with multiple lung metastases and a solitary splenic metastasis, and its ongoing progressive nature. This case was discussed in the tumour board meeting.

INTERVENTIONS

A decision was made to commence treatment with immunotherapy in the form of PD-1 inhibitor (programmed cell death 1 receptor) pembrolizumab. Follow-up restaging computer tomography (CT) scan of the abdomen and chest showed a significant reduction in the lung and chest wall lesions, but the splenic lesion remained unchanged. Given the lack of response to treatment in the splenic metastasis and the significant decrease in lung metastases, the multidisciplinary team decided that a partial splenectomy combined with continued immunotherapy treatment would be appropriate as the success of immunotherapy was imminent within the splenic preservation.

OUTCOMES

The postoperative recovery was smooth and the patient was discharged from hospital on the sixth postoperative day with normal platelets and white blood cells. The histopathological analysis of the resected specimen showed a metastatic melanoma with negative margins.At 10-month follow-up after the splenic resection the patient had not experienced further tumour recurrences.

LESSONS

Spleen-preserving resection for an isolated, solitary splenic metastasis of melanoma is a feasible approach as it not only preserves the ongoing efficacy of checkpoint inhibitors by preserving the physiological T cell milieu, but the immunomodulation properties of RF can produce potentially additional therapeutic benefit.

Recent Advances: The Imbalance of Immune Cells and Cytokines in the Pathogenesis of Hepatocellular Carcinoma

Recent advancement in the immunological understanding of genesis of hepatocellular carcinoma (HCC) has implicated a decline in anti-tumour immunity on the background of chronic inflammatory state of liver parenchyma. The development of HCC involves a network of immunological activity in the tumour microenvironment involving continuous interaction between tumour and stromal cells. The reduction in anti-tumour immunity is secondary to changes in various immune cells and cytokines, and the tumour microenvironment plays a critical role in modulating the process of liver fibrosis, hepatocarcinogenesis, epithelial-mesenchymal transition (EMT), tumor invasion and metastasis. Thus, it is considered as one of primary factor behind the despicable tumour behavior and observed poor survival; along with increased risk of recurrence following treatment in HCC. The primary intent of the present review is to facilitate the understanding of the complex network of immunological interactions of various immune cells, cytokines and tumour cells associated with the development and progression of HCC.

Systemic meta-analysis assessing the short term applicability of early conversion to mammalian target of rapamycin inhibitors in kidney transplant

AIM

To consolidate the present evidence of effectiveness in renal functioning and graft survival following early introduction of mammalian target of rapamycin (mTOR) inhibitors with or without calcineurin inhibitors (CNIs) in renal transplant recipients.

METHODS

We analysed the current literature following PROSPERO approval describing the role of immunosuppressive agent, mTOR inhibitors as an alternative to CNI within six months of renal transplant by searching the PubMed, EMBASE, Cochrane, Crossref, and Scopus using MeSH terms.

RESULTS

Six articles of early withdrawal of CNI and introduction of mTOR-inhibitors within six months of renal transplantation were sought. Glomerular filtration rate (GFR) and serum creatinine were significantly better in mTOR inhibitor group with equivalent survival at 12 mo, even though Biopsy Proven Acute rejection was significantly higher in mTOR-inhibitor group.

CONCLUSION

The evidence reviewed in this meta-analysis suggests that early introduction mTOR-inhibitors substantial CNI minimization. The mTOR inhibitors such as everolimus and sirolimus, due to their complementary mechanism of action and favourable nephrotoxicity profile; better glomerular filtration, lower serum creatinine with equivalent survival. Having said that, due to the higher rejection rate, may influence the use of these regimens to patients with moderate to high immunological risk patients.