The role of neo-adjuvant therapy in cholangiocarcinoma: A systematic review

Introduction

Cholangiocarcinoma (CCA) is the most common malignancy affecting the biliary tree. The only curative treatment is surgical resection, aiming for negative margins (R0). For those who have locally advanced disease, which is borderline resectable, neoadjuvant chemoradiation presents an opportunity to reduce tumour size and allow for surgical resection. The aim of this review is to establish the role of neoadjuvant therapy in each subtype of CCA and establish its impact on survival.

Methods

Search terms such as 'neoadjuvant therapy' and 'cholangiocarcinoma' were searched on multiple databases, including Pubmed, Ovid and Embase. They were then reviewed separately by two reviewers for inclusion criteria. 978 studies were initially identified from the search strategy, with 21 being included in this review.

Results

5,009 patients were included across 21 studies. 1,173 underwent neoadjuvant therapy, 3,818 had surgical resection alone. 359 patients received Gemcitabine based regimes, making it the most commonly utilised regimen for patients CCA and Biliary Tract Cancer (BTC). Data on tolerability of regimes was limited. All included papers were found to have low risk of bias when assessed using The Newcastle Ottawa Scale. Patients who underwent neoadjuvant therapy had a similar median overall survival compared to those who underwent upfront surgery (38.4 versus 35.1 months respectively). Pre-operative CA19-9, microvascular invasion, perineurial invasion and positive lymph nodes were of prognostic significance across BTC and CCA subtypes.

Conclusion

Neoadjuvant therapy and surgical resection is associated with improved patient outcomes and longer median overall survival compared to therapy and upfront surgery, however heterogeneity between research papers limited the ability to further analyse the significance of these results. Although initial studies are promising, further research is required in order to define suitable treatment protocols and tolerability of neoadjuvant regimes.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42020164781.

Consensus Report From the Miami Liver Proton Therapy Conference

An international group of 22 liver cancer experts from 18 institutions met in Miami, Florida to discuss the optimal utilization of proton beam therapy (PBT) for primary and metastatic liver cancer. There was consensus that PBT may be preferred for liver cancer patients expected to have a suboptimal therapeutic ratio from XRT, but that PBT should not be preferred for all patients. Various clinical scenarios demonstrating appropriateness of PBT vs. XRT were reviewed.

Systemic therapy for unresectable, mixed hepatocellular-cholangiocarcinoma: treatment of a rare malignancy

BACKGROUND

Combined hepatocellular-cholangiocarcinoma (HCC-CC) has a reported incidence of less than 5% of primary hepatic malignancies. The treatment approach to this malignancy is undefined. Our objective of this case series is to provide some insight into chemotherapy and/or targeted therapy in this setting.

METHODS

Pathologic and radiographic review confirmed seven combined HCC-CC patients during a 5-year time frame [2009-2014]. Data points were demographics, chemotherapy and/or targeted therapy given in the first and second-line setting, localized treatment if given, first radiographic result, progression-free survival (PFS), and overall survival (OS).

RESULTS

Seven patients were identified. Front-line treatment showed a median PFS of 3.4 months. Total median OS was 8.3 months. Regimens given included gemcitabine alone +/- bevacizumab, gemcitabine + platinum (GP) +/- bevacizumab, and sorafenib. Front-line treatment with these regimens showed progressive disease in 71% (5 patients) on first radiographic scan with all patients who received sorafenib front-line progressing at that restaging. Disease-control (complete response + partial response + stable disease) was seen in 29% of patients (2 patients) with 1 patient receiving GP and 1 patient receiving gemcitabine + bevacizumab. Of note, 2 patients that received GP +/- bevacizumab in the second-line setting had disease control on first radiographic scan.

CONCLUSIONS

Our retrospective review speaks to the rarity of this malignancy and challenges that are associated with its diagnosis and treatment. GP +/- bevacizumab showed disease control in first or second-line treatment in 3 patients. Treatment with this regimen in this rare malignancy subgroup warrants further investigation.

Radiation therapy for hepatobiliary malignancies

Hepatobiliary malignancies represent a heterogeneous group of diseases, which often arise in a background of underlying hepatic dysfunction complicating their local management. Surgical resection continues to be the standard of care for hepatocellular carcinoma (HCC) and cholangiocarcinoma (CC); unfortunately the majority of patients are inoperable at presentation. The aggressiveness of these lesions makes locoregional control of particular importance. Historical experience with less sophisticated radiotherapy resulted in underwhelming efficacy and oftentimes prohibitive liver toxicity. However, with the advent of extremely conformal and precise radiotherapy delivery, dose escalation to the tumor with sparing of surrounding normal tissue has yielded notable improvements in efficacy for this modality of treatment. Dose escalation has come in a variety of forms most notably as stereotactic body radiation therapy (SBRT) and hypofractionated proton therapy. As radiation techniques continue to improve, their proper incorporation into the local management of hepatobiliary malignancies will be paramount in improving the prognosis of what is a grave diagnosis.

A genetic database can be utilized to identify potential biomarkers for biphenotypic hepatocellular carcinoma-cholangiocarcinoma

BACKGROUND

Biphenotypic hepatocellular carcinoma-cholangiocarcinoma (HCC-CC) is an uncommon primary liver neoplasm. Due to limitations in radiologic imaging for the diagnosis of this condition, biopsy is a common method for diagnosis, which is invasive and holds potential complications. To identify alternative means for obtaining the diagnosis and assessing the prognosis of this condition, we evaluated biomarkers for biphenotypic HCC-CC using a genetic database.

METHODS

To evaluate the genetic associations with each variable we utilized GeneCards(®), The Human Gene Compendium (http://www.genecards.org). The results of our search were entered into the Pathway Interaction Database from the National Cancer Institute (PID-NCI) (http://pid.nci.nih.gov), to generate a biomolecule interaction map.

RESULTS

The results of our query yielded 690 genes for HCC, 98 genes for CC and 50 genes for HCC-CC. Genes depicted in this analysis demonstrate the role of hormonal regulation, embryonic development, cell surface adhesion, cytokeratin stability, mucin production, metalloproteinase regulation, Ras signaling, metabolism and apoptosis. Examples of previously described markers included hepatocyte growth factor (HGF), mesenchymal epithelial transition (MET) and Kirsten rat sarcoma viral oncogene homolog (KRAS). Novel markers included phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha (PIK3CA), GPC3, choline kinase alpha (CHKA), prostaglandin-endoperoxide synthase 2 (PTGS2), telomerase reverse transcriptase (TERT), myeloid cell leukemia 1 (MCL1) and N-acetyltransferase 2 (NAT2).

CONCLUSIONS

GeneCards is a useful research tool in the genetic analysis of low frequency malignancies. Utilizing this tool we identified several biomarkers are methods for diagnosing HCC-CC. Finally, utilizing these methods, HCC-CC was found to be predominantly a subtype of CC.

Advances in loco-regional palliation of unresectable cholangiocarcinomas

Cholangiocarcinoma (CC) represents the second most common primary hepatic malignancy after hepatocellular carcinoma, accounting for 10% to 15% of primary liver tumors. Its prognosis is often poor due to its late presentation and its relative resistance to current chemotherapy and radiotherapy regimens. At the time of diagnosis, more than half of the patients are not candidates for surgical therapy due to either invasion of vascular structures or distant metastases. Therefore, for a large proportion of patients, palliation remains the only option for better quality of life and, in some circumstances, longer survival. The main goals of palliative interventions for CC are: restoration of the biliary drainage and resolution of pruritis caused by obstructive jaundice, improvement of the nutritional status and reduction of pain. During the last decades, novel therapies have been introduced to optimize the management of patients with unresectable CC. These therapies can be resource intensive and have some adverse effects; therefore patient selection is crucial. This article discusses the current options for palliation of CC.

Von Hippel-Lindau status influences phenotype of liver cancers arising from PTEN loss

BACKGROUND

PTEN loss contributes to the development of liver diseases including hepatic steatosis and both hepatocellular carcinoma (HCC) and cholangiocarcinoma (CC). The factors that influence the penetrance of these conditions are unclear. We explored the influence of sustained hypoxia signaling through co-deletion of Pten and Vhl in a murine model.

METHODS

We used a CreER-linked Keratin 18 mouse model to conditionally delete Pten, Vhl or both in somatic cells of adult mice, evaluating the resultant tumors by histology and gene expression microarray. Existing sets of gene expression data for human HCC and CC were examined for pathways related to those observed in the murine tumors, and a cohort of human CC samples was evaluated for relationships between HIF-1α expression and clinical outcomes.

RESULTS

Both Pten deletion genotypes developed liver tumors, but with differing phenotypes. Pten deletion alone led to large hepatic tumors with widespread hepatosteatosis. Co-deletion of Pten and Vhl with the Keratin 18 promoter resulted in reduced steatosis and a reduced tumor burden that was characterized by a trabecular architecture similar to CC. Genes associated with hepatic steatosis were coordinately expressed in the human HCC dataset, while genes involved in hypoxia response were upregulated in tumors from the human CC dataset. HIF-1α expression and overall survival were examined in an independent cohort of human CC tumors with no statistical differences uncovered.

CONCLUSION

Pten deletion in Keratin 18 expressing cells leads to aggressive tumor formation and widespread steatosis in mouse livers. Co-deletion of Vhl and Pten results in lower tumor burden with gene expression profiling suggesting a switch from a profile of lipid deposition to an expression profile more consistent with upregulation of the hypoxia response pathway. A relationship between tumor hypoxia signaling and altered hepatic steatotic response suggests that competing influences may alter tumor phenotypes.