Investigation of Liver-directed Therapies for Cancer Patients throughout the United States

Elisa Thomas^*
*Correspondence: Elisa Thomas, Department of Endocrinology and Diabetology, University of Louisville, Louisville, KY 40202, USA, Email:

Description

Cancer remains one of the most challenging and prevalent diseases worldwide, causing millions of deaths annually. Liver-directed therapies have emerged as a promising approach in the treatment of cancer patients, particularly those with liver metastases. The United States has been at the forefront of medical research and innovation, and this article explores the investigation of liver-directed therapies for cancer patients throughout the country. It will provide an in-depth look into the types of therapies, their applications, the challenges they present, and the advancements that have been made in recent years. The liver is a common site for metastases in many types of cancer, including colorectal, breast, and lung cancer. Liver metastases can significantly impact a patient's prognosis and quality of life. Traditional treatment options for liver metastases include surgery, chemotherapy, and radiation therapy. However, these treatments may not always be effective, and they can be associated with significant side effects [1].

Liver-directed therapies, also known as loco regional therapies, have gained attention due to their ability to directly target cancer cells in the liver while sparing healthy surrounding tissue. These therapies offer a valuable alternative for patients with liver metastases, often in combination with systemic treatments. Hepatic resection, or surgical removal of the tumor, is a well-established treatment for liver metastases. In the United States, this approach is often used for patients with limited metastatic disease. Advances in surgical techniques, including laparoscopic and robotic-assisted procedures, have made hepatic resection more accessible and less invasive [2]. Liver transplantation is another surgical option for select patients with unrespectable liver metastases. However, strict criteria must be met, and donor organs are in limited supply. The United Network for Organ Sharing (UNOS) oversees the allocation of donor livers, and many transplant centers in the U.S. perform liver transplants as a part of their liver-directed cancer therapy programs.

Radiofrequency Ablation (RFA) is a minimally invasive procedure that uses heat to destroy cancer cells. It is a common liver-directed therapy in the United States for patients who are not candidates for surgery. RFA is often used for smaller liver tumors and can be performed percutaneously, laparoscopically, or during an open surgical procedure. Microwave ablation is a newer technique that uses microwave energy to heat and destroy cancer cells. While it is similar in concept to RFA, microwave ablation may have advantages in terms of larger ablation zones and shorter procedure times. Several healthcare facilities in the United States have adopted this method. Cryoablation, or cryotherapy, involves freezing and thawing cancer cells to induce cell death. It is often considered for patients with small liver tumors. Cryoablation is less common than RFA or microwave ablation but is still utilized in certain cases [3].

Transarterial Chemoembolization (TACE) is a widely used liver-directed therapy in the United States for patients with Hepatocellular Carcinoma (HCC) or liver metastases from colorectal cancer. This procedure involves the administration of chemotherapy directly into the hepatic artery, followed by the embolization of blood vessels supplying the tumor. TACE can effectively treat liver lesions and may be used in conjunction with other therapies. Selective Internal Radiation Therapy (SIRT), also known as radio embolization, is a treatment that delivers radioactive microspheres directly to liver tumors. It is primarily used for patients with liver-dominant metastases from colorectal cancer. SIRT is offered at specialized centers across the United States and has shown promising results in extending the survival of patients.

The clinical applications of liver-directed therapies are broad, and their effectiveness depends on various factors, including the type of cancer, the stage of disease, and the patient's overall health. Several clinical trials and studies in the United States have investigated the efficacy of these therapies. Colorectal cancer frequently spreads to the liver, and liver-directed therapies play a significant role in managing the disease. A multi-center study published in the Journal of Clinical Oncology in 2017 demonstrated that adding liverdirected therapies to systemic chemotherapy significantly improved the survival of patients with metastatic colorectal cancer.

Hepatocellular Carcinoma (HCC), the most common type of liver cancer, has also seen significant advancements in treatment. A study published in the New England Journal of Medicine in 2017 showed that SIRT with yttrium-90 resin microspheres improved overall survival and reduced tumor-related symptoms in patients with unrespectable HCC. While liver metastases are more common in colorectal and HCC, they can occur in other types of cancer, including breast and lung cancer. Several clinical trials in the United States have explored the use of liver-directed therapies for these patients, with varying degrees of success [4].

Selecting the right patients for these therapies is crucial. It requires careful evaluation of factors such as tumor size, location, and overall health. Inappropriate patient selection can lead to suboptimal outcomes. In many cases, liver-directed therapies are used in combination with systemic treatments, such as chemotherapy or immunotherapy. Coordination of care and timing of treatments are essential to ensure the best outcomes. The cost of liver-directed therapies can be significant. Insurance coverage and reimbursement for these treatments vary, and some patients may face financial barriers to accessing these therapies. While liver-directed therapies can offer excellent short-term results, long-term outcomes and potential side effects need further investigation. Close monitoring of patients is essential to assess the durability of these treatments. Advances in imaging and technology, such as the development of more precise ablation techniques and better radiation delivery, continue to drive improvements in liver-directed therapies. Not all healthcare facilities in the United States offer liver-directed therapies. Patients may need to travel to specialized centers, potentially causing logistical and financial challenges [5].

Acknowledgement

None.

Conflict of Interest

There are no conflicts of interest by author.

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