Understanding Breast Cancer Metastasis

This is the 4364th article of Da Yi Xiao Hu

In 2015, young singer Yao Beina passed away due to breast cancer recurrence and multi-organ metastasis. Breast cancer is one of the most common malignant tumors in women. In recent years, with the rapid improvement of diagnosis and treatment technology, the survival of breast cancer patients has been continuously extended, but recurrence and metastasis still seriously affect the prognosis of patients. This article will introduce you to breast cancer metastasis from three aspects: metastasis pathway, clinical manifestations, and post-metastasis treatment.

Transfer pathways

① Local expansion

Cancer cells can spread along the duct or fascial space and then invade Cooper's ligament and skin;

② Lymphatic metastasis

There are two main pathways. The first is that cancer cells invade the ipsilateral axillary lymph nodes through the lymphatic vessels at the lateral edge of the pectoralis major muscle, then invade the subclavian lymph nodes and even the supraclavicular lymph nodes, and then invade the venous blood flow through the thoracic duct or right lymphatic vessels to metastasize to distant sites. The second is that cancer cells drain to the parasternal lymph nodes along the intercostal perforators of the internal mammary vessels to the medial lymphatic vessels, and then reach the supraclavicular lymph nodes, and can invade the blood flow through the same pathway.

③ Blood transfer

Breast cancer is a systemic disease. Most studies have found that early breast cancer can also metastasize through the blood. Cancer cells can enter the veins through the lymphatic pathway, or directly invade the blood circulation to cause distant metastasis. Common distant metastasis sites include bones, lungs, liver, etc.

Clinical manifestations

① Cooper's ligament and skin

Involvement of the Cooper ligament can shorten it and cause depression of the skin on the surface of the tumor, the so-called "dimple sign". When the skin is involved, skin edema may occur, presenting an "orange peel-like" or ulcerative changes.

② Lymph nodes

When breast cancer first metastasizes to the lymph nodes, it is more common in the axillary lymph nodes. The swollen lymph nodes are hard, painless, and can be moved. Later, their number increases and they fuse into clumps, and they may even adhere to the skin or deep tissues and become difficult to move.

③ Distant metastasis

When breast cancer metastasizes to the lungs, chest pain, shortness of breath, and difficulty breathing may occur; when it metastasizes to the liver, hepatomegaly, jaundice, and persistent pain in the liver area may occur, and some patients may have digestive dysfunction; when it metastasizes to the bones, persistent pain in the bones and joints and pathological fractures may occur; when it metastasizes to the brain, persistent headaches, blurred vision, nausea and vomiting may occur.

Post-metastasis treatment

Endocrine therapy, chemotherapy, and anti-Her-2 drug therapy are the basic treatments for recurrent and metastatic breast cancer. Combined with reasonable local treatment, they can better control the related symptoms of distant metastasis of breast cancer and improve the patient's prognosis.

Endocrine therapy should be given priority for patients with hormone receptor-positive disease, relatively slow disease progression, no visceral metastasis, and non-endocrine primary resistance;

Chemotherapy should be given priority for patients with negative hormone receptors, short postoperative disease-free interval, visceral metastasis, and no response to endocrine therapy;

Patients with Her-2-positive breast cancer should be treated with anti-Her-2 therapy;

Commonly used methods of local treatment include surgical resection of lesions, stereotactic radiotherapy, and arterial interventional treatment for patients with liver metastases.

In summary, breast cancer cells metastasize mainly through three pathways, which can affect distant organs such as bones, lungs, and liver, but research on treatment options for breast cancer metastasis is also ongoing. Breast cancer metastasis is not terrible, and it is more important to have a correct understanding and actively prevent and treat it. To reduce the adverse effects of breast cancer metastasis, regular physical examinations should be performed before surgery to achieve early detection, early diagnosis, and early treatment of breast cancer. This is the fundamental reason for the prognosis and efficacy. Tumor treatment should be standardized and timely, with regular follow-up. These can detect any signs of breast cancer early, allowing us to intervene in time, which will have a similar effect to early diagnosis.

Author: Wang Yaru

Reviewer: Qian Mingping