The Role of HER2 Status in the Biliary Tract Cancers

Exploring Zanidatamab's efficacy across HER2-positive Malignancies: a narrative review

BACKGROUND

HER2-positive cancers involve amplification or overexpression of the HER2 gene, leading to aggressive tumor growth across several cancer types, including breast, gastric, ovarian, and pancreatic cancers. Detection methods such as immunohistochemistry, next-generation sequencing, and fluorescence in situ hybridization are used, with new advancements like biosensors and circulating tumor DNA offering improved diagnostic potential. Treatment strategies have evolved, including anti-HER2 drugs like trastuzumab and newer agents like zanidatamab, which show promise against HER2-positive malignancies.

METHODS

A comprehensive search of the following academic databases was performed including PubMed, Cochrane Library, and clinicaltrials.gov. A detailed search string was made. Studies were selected based on whether they contained the keywords and if they reported the details of treatment for zanidatamab. A total of 16 studies were selected. Abstracts were independently examined by one author and critically reviewed by another and if there were any conflicting viewpoints they were discussed until consensus was reached.

DISCUSSION

Zanidatamab has shown promising clinical outcomes in several HER2-positive cancers, including biliary tract, breast, gastric, and lung cancers, with high disease control rates and progression-free survival. Although it is not yet FDA-approved, it has received priority review for HER2-positive biliary tract cancer, with an FDA decision expected in November 2024. The safety profile of zanidatamab has been well-studied. The most common side effects include diarrhea, infusion reactions, and other mild to moderate treatment-related adverse events. In combination with Palbociclib for HER2-positive breast cancer, more severe side effects were observed, resulting in some patients discontinuing treatment. However, no treatment-related deaths have been reported across trials. While its anticancer efficacy and manageable safety profile are promising, long-term safety and efficacy data are still needed. Early clinical trials demonstrate strong efficacy, though some side effects, such as diarrhea and decreased ejection fraction, were noted. Future research should focus on understanding potential resistance mechanisms and establishing zanidatamab's broader role in the treatment landscape of HER2-positive cancers.

CONCLUSION

In summary, zanidatamab has shown significant tumor response, progression-free survival, disease control, and improved quality of life in early trials, however, the lack of long-term safety and efficacy data remains a key limitation, requiring further research.

Antibody-Drug Conjugates and Their Potential in the Treatment of Patients with Biliary Tract Cancer

Background: Biliary tract cancers (BTCs) are aggressive in nature, often presenting asymptomatically until they are diagnosed at an advanced stage. Surgical resection or liver transplantation are potential curative options. However, a large proportion of patients present with incurable locally advanced or metastatic disease and most of these patients are only eligible for palliative chemotherapy or best supportive care. More recently, targeted therapies have proven beneficial in a molecularly selected subgroup of patients with cholangiocarcinoma who have progressed on previous lines of systemic treatment. However, only a minority of patients with BTCs whose tumours harbour specific molecular alterations can access these therapies. Methods: In relation to ADCs, studies regarding use of antibody-drug conjugates in cancer, particularly in BTCs, were searched in Embase (1974 to 2024) and Ovid MEDLINE(R) (1946 to 2024) to obtain relevant articles. Examples of current clinical trials utilising ADC treatment in BTCs were extracted from the ClinicalTrials.gov trial registry. Conclusions: Overall, this review has highlighted that ADCs have shown encouraging outcomes in cancer therapy, and this should lead to further research including in BTCs, where treatment options are often limited. The promising results observed with ADCs in various cancers underscore their potential as a transformative approach in oncology, warranting continued exploration and development and the need for education on the management of their specific toxicities. By addressing current challenges and optimising ADC design and application, future studies could potentially improve treatment outcomes for patients with BTCs and beyond, potentially in both early and advanced stage settings.

Prognostic Significance of EGFR, HER2, and c-Met Overexpression in Surgically Treated Patients with Adenocarcinoma of the Ampulla of Vater

Adenocarcinoma of the ampulla of Vater (AAC) is a rare malignancy with heterogeneous tumors arising from various histologic subtypes, necessitating new therapeutic strategies. This study examines epidermal growth factor receptor (EGFR), human epidermal growth factor receptor 2 (HER2), and c-Met expression in AAC, given their potential as druggable targets. Among 87 patients who underwent curative resection, EGFR overexpression was found in 87.4%, HER2 in 11.5%, and c-Met in 50%. EGFR overexpression was more common in the pancreatobiliary subtype (p = 0.018) and associated with a higher histologic grade (p = 0.008). HER2 did not correlate with clinicopathological features, while c-Met was more common in node-negative groups (p = 0.004) and often co-expressed with EGFR (p = 0.049). EGFR-positive patients had worse disease-free (HR = 2.89; 95% CI, 1.35-6.20; p = 0.061) and overall survival (HR = 6.89; 95% CI, 2.94-16.2; p = 0.026) than EGFR-negative patients. HER2-positive AAC showed a trend towards shorter survival, although not statistically significant, and c-Met had no impact on survival outcomes. In the context of systemic disease, survival outcomes did not vary according to EGFR, HER2, and c-Met expression, but the HER2-positive group showed a trend towards inferior progression-free survival (HR = 1.90; 95% CI, 0.56-6.41; p = 0.166). This study underscores the potential of EGFR, HER2, and c-Met as targets for personalized therapy in AAC, warranting further research to evaluate targeted treatments.

Emerging targeted therapies and strategies to overcome resistance in biliary tract cancers

In the last decade, targeted therapies have shown rapid advancement in biliary tract cancer (BTC). Today, many targeted agents are available and under investigation for patients with BTC. More recently, immune checkpoint inhibitors (ICI) such as durvalumab and pembrolizumab in combination with gemcitabine plus cisplatin (gem/cis) have resulted in improved overall survival and progression-free survival in the first-line setting. However, the efficacy benefit of these novel therapeutics is often short-lived, with literature outlining concerns about both primary and secondary resistance to these agents. Investigators also need to consider toxicity profiles that can emerge using this strategy. There have been efforts to reduce evolving resistance through combinatory approaches, both pre-clinically and in early clinical settings. This review summarizes the emerging targeted therapies in BTC, evolving biomarkers of resistance, strategies to overcome them, and an analysis of ongoing clinical trials of patients with advanced BTC.

The Current Role of Radiation in the Management of Cholangiocarcinoma-A Narrative Review

Cholangiocarcinoma (CCA) is a rare cancer of bile ducts. It is associated with a poor prognosis. The incidence of CCA is rising worldwide. Anatomical subgroups have been used to classify patients for treatment and prognosis. There is a growing understanding of clinically important distinctions based on underlying genetic differences that lead to different treatment options and outcomes. Its management is further complicated by a heterogeneous population and relative rarity, which limits the conduct of large trials to guide management. Surgery has been the primary method of therapy for localized disease; however, recurrence and death remain high with or without surgery. Therefore, there have been concerted efforts to investigate new treatment options, such as the use of neoadjuvant treatments to optimize surgical outcomes, targeted therapy, leveraging a new understanding of immunobiology and stereotactic radiation. In this narrative review, we address the evidence to improve suboptimal outcomes in unresectable CCA with radiation, as well as the role of radiation in neoadjuvant and postoperative treatment. We also briefly discuss the recent developments in systemic treatment with targeted therapies and immune checkpoint inhibitors.

Impact of Medicaid expansion on the multimodal treatment of biliary tract cancer

INTRODUCTION

The impact of Medicaid expansion (ME) on the treatment of patients with cancer remains controversial, especially individuals requiring complex multidisciplinary care. We sought to evaluate the impact of Medicaid expansion (ME) on receipt of multimodal care, including surgical resection, for Stage I-III biliary tract cancer (BTC).

METHODS

Patients diagnosed with BTC between 40 and 65 years of age were identified from the National Cancer Database and divided into pre- (2008-2012) and post- (2015-2018) ME cohorts. Difference-in-difference (DID) analysis was used to determine the impact of ME on the utilization of surgery and multimodal chemotherapy and/or radiotherapy treatment for BTC.

RESULTS

Among 12,415 patients with BTC (extrahepatic, n = 5622, 45.3%; intrahepatic, n = 4352, 35.1%; gallbladder, n = 1944, 15.7%; overlapping, n = 497, 4.0%), 5835 (47.0%) and 6580 (53.0%) patients were diagnosed before versus after ME, respectively. Overall utilization of surgery (OR 1.13, 95% CI 1.02-1.26) and multimodality therapy (OR 1.13, 95% CI 1.01-1.27) increased in states that adopted ME. Utilization of surgery among uninsured/Medicaid patients in ME states increased relative to patients living in non-ME states (∆+10.1%, p = 0.01). Similarly, the use of multimodal treatment increased among uninsured/Medicaid patients living in ME versus non-ME states (∆+6.4%, p = 0.04); in contrast, there were no difference among patients with other insurance statuses (overall: ∆+1.5%, private: ∆-2.0%, other: ∆+3.9%, all p > 0.5). Uninsured/Medicaid patients with BTC who lived in a ME state had a lower risk of long-term death in the post-ME era (HR 0.81, 95% CI 0.67-0.98; p = 0.03).

CONCLUSIONS

Implementation of ME positively impacted survival among patients who underwent surgical and multimodal treatment for Stage I-III BTC.

Molecular Profile of Intrahepatic Cholangiocarcinoma

Intrahepatic cholangiocarcinoma (ICC) is a relatively uncommon but highly aggressive primary liver cancer that originates within the liver. The aim of this study is to review the molecular profile of intrahepatic cholangiocarcinoma and its implications for prognostication and decision-making. This comprehensive characterization of ICC tumors sheds light on the disease's underlying biology and offers a foundation for more personalized treatment strategies. This is a narrative review of the prognostic and therapeutic role of the molecular profile of ICC. Knowing the molecular profile of tumors helps determine prognosis and support certain target therapies. The molecular panel in ICC helps to select patients for specific therapies, predict treatment responses, and monitor treatment responses. Precision medicine in ICC can promote improvement in prognosis and reduce unnecessary toxicity and might have a significant role in the management of ICC in the following years. The main mutations in ICC are in tumor protein p53 (TP53), Kirsten rat sarcoma virus (KRAS), isocitrate dehydrogenase 1 (IDH1), and AT-rich interactive domain-containing protein 1A (ARID1A). The rate of mutations varies significantly for each population. Targeting TP53 and KRAS is challenging due to the natural characteristics of these genes. Different stages of clinical studies have shown encouraging results with inhibitors of mutated IDH1 and target therapy for ARID1A downstream effectors. Fibroblast growth factor receptor 2 (FGFR2) fusions are an important target in patients with ICC. Immune checkpoint blockade can be applied to a small percentage of ICC patients. Molecular profiling in ICC represents a groundbreaking approach to understanding and managing this complex liver cancer. As our comprehension of ICC's molecular intricacies continues to expand, so does the potential for offering patients more precise and effective treatments. The integration of molecular profiling into clinical practice signifies the dawn of a new era in ICC care, emphasizing personalized medicine in the ongoing battle against this malignancy.

[Assessment of HER2 status of carcinomas of various localizations]

A detailed description of the methodological aspects of the evaluation of HER2-status in carcinomas of such localizations as the mammary gland, pancreas, salivary glands, stomach, colon, endometrium, bladder, lungs is presented. Approaches and criteria for assessing HER2 status from methodological and clinical points of view are analyzed. The data are systematized in tables for use in practical diagnostic work.