The latest cancer report released by the National Cancer Center of China revealed the incidence and mortality rates of cancer in China in 2016. According to the report, in 2016, there were 2.4135 million deaths from cancer in China, with nearly 6,600 people losing their lives to cancer every day on average. Lung cancer, liver cancer, gastric cancer, colorectal cancer, and esophageal cancer accounted for 69.3% of all cancer deaths.
In fact, cancer is often not a single disease. Metastatic spread is one of the manifestations of many advanced cancers, and the liver is one of the most common target organs for cancer cell metastasis.
March 18th is National Liver Care Day in China. When people are advocating for liver health, the liver also wants to ask:
Why do so many cancers love me?
Why Does Cancer Favor the Liver?
The primary reason the liver is so "beloved" is because it's just too excellent!
There's a saying, "A good bird chooses a good tree to nest in." Cell growth and development depend on nutrients and blood. With its two blood supply systems, the liver is like a cuisine to cancer cells.
Moreover, the liver is just too kind.
A study published in the journal Nature in 2019 showed that liver cells provide a normal living environment for cancer cells and even tailor-made growth beds for them:
Liver cells react to inflammation by activating the protein STAT3, which then increases the production of other proteins called SAA. These SAA proteins then remodel the liver and create the "soil" needed for cancer cell "seeding."
Which cancers prefer to metastasize to the liver?
Clinically, colorectal cancer, breast cancer, pancreatic cancer, and lung cancer have a higher probability of liver metastasis.
Data shows that 20%-30% of colorectal cancer patients already have distant metastases at the time of diagnosis, 15% of colorectal cancer patients have liver metastases at the time of diagnosis of the primary tumor, and approximately 20% of patients develop liver metastases after colorectal cancer surgery.
The early symptoms of metastatic liver cancer are characterized by primary extraliver tumors, and its own symptoms are not obvious, usually found during preoperative examination, postoperative follow-up, or exploratory laparotomy.
As the disease progresses and the tumor grows, symptoms of the liver gradually appear, including clinical features of primary tumors, liver cancer, and changes in overall condition. Typical symptoms include liver area pain, fatigue, weight loss, fever, loss of appetite, and upper abdominal mass.
Metastatic liver cancer may be accompanied by jaundice, ascites, cachexia (extreme weight loss), etc.
Is metastatic liver cancer more difficult to treat?
Clinical studies have shown that patients with cancer cells spreading to the liver often have a worse prognosis.
In 2021, a study of 718 cancer patients conducted by the University of Michigan in the United States showed that compared with patients with cancer cells spreading but not to the liver, patients with cancer cells spreading to the liver had a poorer response to immunotherapy.
What's even more surprising is that researchers found that the prognosis of patients with liver metastases receiving chemotherapy or targeted therapy was no worse than that of patients with other types of metastases. This suggests that patients with cancer cell liver metastases are only insensitive to immunotherapy.
In other words, although current immunotherapy is minimally effective for patients with liver metastases, there are still many methods available to achieve an ideal prognosis for patients.
However, it is important to note that liver metastatic cancer is not primary liver cancer. Although they share the same space, the biological activity of metastatic cancer is still the same as that of the tumor in the primary site, so it is necessary to first identify the primary cancer organ before coordinating local liver treatment.
