Liver Metastases

Liver Metastases Therapy - Chances of Recovery And Life Expectancy

By far, the most frequent malignant neoplasms in the liver are liver metastases. These are cancerous metastases that originate from tumors that are distant from the liver.

The following tumors most frequently metastasize to the liver in decreasing order:

• Carcinomas of the lung ( lung cancer)
• Colon cancer (colon cancer and rectal cancer)
• Pancreatic cancer (carcinoma of the pancreas)
• Breast cancer (breast carcinoma)
• Cancer of the esophagus (esophageal cancer)
• Gastric cancer

What Are Liver Metastases And How Do They Develop?

Liver metastases are so-called malignant secondary tumors, as they have emigrated from other primary tumors. Tumors that originate directly from liver cells are primary tumors of the liver, such as liver cancer (hepatocellular carcinoma). The tumor cells are spread partly via the bloodstream (haematogenic spread) and partly via the lymphatic system (lymphogenic spread).

Tumors of the digestive organs, such as colon cancer, stomach cancer, or pancreatic cancer, spread mainly hematogenous (via the bloodstream) via the portal vein to the liver, the central metabolic organ of humans. Liver metastases are usually already multiplied at diagnosis. The number, appearance, size, and location of the tumor metastases are decisive for planning further treatment.

Healing of Liver Metastases Usually Only by Complete Removal of the Tumor

The therapy of tumor diseases of the liver is usually carried out by an interdisciplinary team of specialists. These include abdominal surgeons (visceral surgeons) specializing in liver surgery, radiotherapists (radiologists), cancer specialists (oncologists), and pathologists.

Malignant neoplasms of the liver can usually only be cured by liver surgery with complete removal of the tumor tissue, which is often, especially in the case of metastases, no longer possible due to an advanced stage of the disease. There are, however, various therapeutic approaches that can help patients regain quality of life and lifetime.

Particularly in the case of metastases, it should be ensured before attempting surgical removal that the primary tumor, e.g., colon cancer, has healed, and no further tumor seeds are in the body.

An attempt of surgical removal even of a large number of liver metastases, for example, colorectal carcinomas (colon cancer), is possible in otherwise healthy patients. Since the liver has a very rapid regenerative capacity, removal of tumor metastases can be carried out in several stages (stage resection) in cases of severe organ damage.

If metastases cannot be eradicated, because of their large number or size, chemotherapy can help to restore the option to resect (complete removal of the tumor) or partial removal. Chemotherapy carried out before tumor removal to reduce the size of the tumor and make surgery easier is called "neoadjuvant chemotherapy."

Therapy Concepts for Inoperable Liver Metastases

Metastases that cannot be removed by surgery are usually treated palliatively (not curatively) with chemotherapy. Besides, there are thermal ablation procedures, such as radiofrequency ablation (RFA), which uses local heat to reduce the size of the tumor.

In "transarterial chemoembolization" (TACE), a chemotherapeutic agent is injected directly, locally, into the tumor tissue via a catheter system in the blood vessels, which allows maximum effect at the site of action with minimum side effects for the surrounding tissue and the patient.

Another treatment method that directly attacks the liver via a catheter is selective internal radiotherapy (SIRT), which involves the targeted injection of radioactive particles into the tumor tissue to act as locally as possible with minimal collateral damage.

A state-of-the-art method for reducing liver metastases is HIFU therapy (ultrasound-guided high-intensity focused ultrasound), in which the tumor cells are heated to the extent that they "coagulate," causing the tumor to shrink. This procedure is still in the early stages, but numerous studies have already shown that HIFU therapy is a successful therapeutic approach with only minor side effects.

According to the current state of knowledge, multimodal therapy concepts are particularly promising, in which liver surgery, chemotherapy, and heat therapy are combined.

Life Expectancy - Survival With Liver Metastases

Without surgical removal, the average survival time at diagnosis depends on the primary tumor (source of metastasis) and is about 4-8 months. With the complete surgical removal of liver metastases from colorectal cancer, 5-year survival rates of up to 45% are found in the literature, i.e., five years after surgery, 45% of cancer patients are still alive.

Sources:

• Innere Medizin, Gerd Herold und Mitarbeiter, 2014
• Chirurgie, Siewert/Stein, 9. Auflage, Springer Verlag
• www.krebsinformationsdienst.de/tumorarten/metastasen/lebermetastasen-grundlagen.php(22.08.2016)