How Does Cancer Travel Through The Body: A Comprehensive Guide?

Are you curious about how cancer spreads throughout the body? At SIXT.VN, we understand the importance of accessible and reliable health information, especially when planning your travels to Vietnam. This article will comprehensively explain cancer metastasis, providing insights into how cancer cells travel and form new tumors. Whether you’re exploring the vibrant streets of Hanoi or relaxing on the beaches of Phu Quoc, understanding health topics empowers you to travel with greater peace of mind.

1. What is Cancer Metastasis and How Does It Begin?

Metastasis is how cancer travels throughout the body; cancer cells break away from the primary tumor, travel through the bloodstream or lymphatic system, and form new tumors in distant organs.

Cancer metastasis is a complex process involving multiple steps that allow cancer cells to spread from the primary tumor to other parts of the body. Understanding how this process works is crucial for developing effective treatments and improving patient outcomes. According to research from the National Cancer Institute (NCI) in 2023, metastasis is responsible for approximately 90% of cancer-related deaths.

1.1. Detachment from the Primary Tumor

The initial stage of metastasis involves cancer cells detaching from the primary tumor. This process is facilitated by changes in cell adhesion molecules, which normally hold cells together. Cancer cells downregulate these molecules, allowing them to separate from the tumor mass.

1.2. Intravasation

After detaching, cancer cells need to enter the bloodstream or lymphatic system to travel to distant sites. This process, known as intravasation, involves cancer cells penetrating the walls of blood vessels or lymphatic vessels. Cancer cells secrete enzymes that degrade the extracellular matrix (ECM), a network of proteins and molecules surrounding cells, allowing them to invade the vessels.

1.3. Survival in Circulation

Once inside the bloodstream or lymphatic system, cancer cells face a hostile environment. They are exposed to shear stress from blood flow and immune cells that can recognize and destroy them. To survive in circulation, cancer cells employ several strategies:

• Clustering: Cancer cells can aggregate with each other or with platelets to form clusters, which may protect them from immune attack and enhance their ability to adhere to blood vessel walls.
• Epithelial-Mesenchymal Transition (EMT): EMT is a process in which cancer cells undergo a phenotypic change, losing their epithelial characteristics and gaining mesenchymal traits. This transition enhances their migratory and invasive properties, as well as their resistance to apoptosis (programmed cell death).

1.4. Extravasation

To form new tumors in distant organs, cancer cells need to exit the bloodstream or lymphatic system and invade the surrounding tissue. This process, known as extravasation, is the reverse of intravasation. Cancer cells adhere to the inner lining of blood vessels (endothelium) and then migrate through the vessel wall into the adjacent tissue.

1.5. Colonization

The final and often rate-limiting step in metastasis is colonization, which involves cancer cells establishing themselves in the new microenvironment and forming a new tumor. This process requires cancer cells to adapt to the local conditions, including the availability of nutrients, growth factors, and interactions with other cells.

• Metastatic Niche: Cancer cells often colonize specific sites in the body that provide a favorable microenvironment for their growth and survival. These sites, known as metastatic niches, are often pre-conditioned by the primary tumor through the release of signaling molecules that attract cancer cells and promote their colonization.
• Angiogenesis: To support their growth, metastatic tumors need to develop their own blood supply through a process called angiogenesis. Cancer cells secrete factors that stimulate the formation of new blood vessels from pre-existing vessels, providing the tumor with oxygen and nutrients.

Alt text: Microscopic view of cancer cells traveling in the bloodstream during metastasis.

2. What Organs Are Most Commonly Affected by Cancer Spread?

Cancer can spread to almost any part of the body, but some organs are more commonly affected than others; this is influenced by blood flow patterns, organ-specific microenvironments, and the type of primary cancer.

Metastasis is a complex process, and the patterns of cancer spread can vary depending on several factors, including the type of primary cancer, the individual patient’s characteristics, and the specific microenvironment of the target organ. According to the American Cancer Society in 2023, understanding these patterns is crucial for developing effective strategies to prevent and treat metastatic disease.

2.1. Bones

Bones are a common site for cancer metastasis, particularly for cancers of the breast, prostate, lung, thyroid, and kidney. Bone metastases can cause pain, fractures, spinal cord compression, and hypercalcemia (high levels of calcium in the blood).

• Mechanism: Cancer cells can reach the bones through the bloodstream or lymphatic system. Once in the bone marrow, they can disrupt the normal balance of bone remodeling, leading to either excessive bone breakdown (osteolysis) or excessive bone formation (osteosclerosis).
• Symptoms: Bone pain is the most common symptom of bone metastases. It can be constant or intermittent and may worsen with activity. Fractures can occur when the bone is weakened by the tumor. Spinal cord compression can cause neurological symptoms such as weakness, numbness, or bowel and bladder dysfunction.

2.2. Liver

The liver is another frequent site of cancer metastasis, particularly for cancers of the colon, rectum, stomach, pancreas, and breast. Liver metastases can cause jaundice (yellowing of the skin and eyes), abdominal pain, weight loss, and liver failure.

• Mechanism: The liver receives a large blood supply from the gastrointestinal tract, making it a prime target for cancer cells that have spread from these organs. Cancer cells can also reach the liver through the hepatic artery, which carries blood from the heart.
• Symptoms: Liver metastases may not cause any symptoms in the early stages. As the tumors grow, they can cause abdominal pain, particularly in the upper right quadrant. Jaundice can occur if the tumors block the bile ducts. Weight loss and fatigue are also common symptoms.

2.3. Lungs

The lungs are a common site for cancer metastasis, as they are the first major organ that blood from other parts of the body passes through. Cancers that commonly spread to the lungs include breast, colon, prostate, bladder, and melanoma. Lung metastases can cause cough, shortness of breath, chest pain, and hemoptysis (coughing up blood).

• Mechanism: Cancer cells can reach the lungs through the bloodstream or lymphatic system. Once in the lungs, they can form nodules or masses that can interfere with breathing.
• Symptoms: Lung metastases may not cause any symptoms in the early stages. As the tumors grow, they can cause cough, shortness of breath, and chest pain. Hemoptysis can occur if the tumors erode into blood vessels.

2.4. Brain

Brain metastases are less common than bone, liver, or lung metastases, but they can have a significant impact on a patient’s quality of life. Cancers that commonly spread to the brain include lung, breast, melanoma, kidney, and colon. Brain metastases can cause headaches, seizures, neurological deficits (weakness, numbness, speech difficulties), and cognitive changes.

• Mechanism: Cancer cells can reach the brain through the bloodstream. Once in the brain, they can form tumors that can compress or invade brain tissue.
• Symptoms: Headaches are the most common symptom of brain metastases. They can be constant or intermittent and may be accompanied by nausea and vomiting. Seizures can occur if the tumors irritate the brain tissue. Neurological deficits can occur depending on the location of the tumors.

2.5. Lymph Nodes

Lymph nodes are part of the lymphatic system, which plays a role in the immune system. Cancer cells can spread to lymph nodes through the lymphatic vessels. Lymph node metastases can cause swelling, pain, and may indicate a higher risk of cancer recurrence.

• Mechanism: Cancer cells can travel through the lymphatic vessels to reach the lymph nodes. Once in the lymph nodes, they can form tumors that can block the flow of lymph fluid.
• Symptoms: Swollen lymph nodes are the most common symptom of lymph node metastases. The swollen nodes may be tender to the touch. In some cases, the swollen nodes can compress nearby structures, causing pain or other symptoms.

Alt text: Lymph node showing metastasis from malignant melanoma.

3. How Do Doctors Determine if Cancer Has Spread?

Doctors use a variety of methods to determine if cancer has spread, including imaging tests, biopsies, and blood tests; determining whether cancer has spread is crucial for staging the cancer and determining the appropriate treatment plan.

Diagnosing cancer metastasis involves a comprehensive approach that combines various diagnostic tools and techniques. According to the National Comprehensive Cancer Network (NCCN) in 2023, accurate detection and staging of metastasis are essential for guiding treatment decisions and improving patient outcomes.

3.1. Imaging Tests

Imaging tests are the primary method for detecting cancer metastasis. These tests can visualize tumors in different parts of the body and help determine the extent of cancer spread.

• CT Scan (Computed Tomography): CT scans use X-rays to create detailed images of the body. They can detect tumors in the lungs, liver, bones, and other organs.
• MRI (Magnetic Resonance Imaging): MRI uses magnetic fields and radio waves to create images of the body. It is particularly useful for detecting tumors in the brain, spinal cord, and soft tissues.
• PET Scan (Positron Emission Tomography): PET scans use radioactive tracers to detect areas of high metabolic activity, which can indicate the presence of cancer cells. PET scans are often combined with CT scans (PET/CT) to provide both anatomical and functional information.
• Bone Scan: Bone scans use radioactive tracers to detect areas of increased bone activity, which can indicate the presence of bone metastases.
• Ultrasound: Ultrasound uses sound waves to create images of the body. It is often used to evaluate the liver, kidneys, and other abdominal organs.

3.2. Biopsies

A biopsy involves removing a small sample of tissue from a suspicious area for examination under a microscope. Biopsies can confirm the presence of cancer cells and help determine the type of cancer.

• Needle Biopsy: A needle biopsy uses a thin needle to remove a sample of tissue. It can be performed under the guidance of imaging tests such as CT scan or ultrasound.
• Surgical Biopsy: A surgical biopsy involves making an incision to remove a larger sample of tissue. It may be necessary if a needle biopsy cannot provide enough tissue for diagnosis.
• Lymph Node Biopsy: A lymph node biopsy involves removing one or more lymph nodes to check for cancer cells. It can be performed as a sentinel lymph node biopsy, which involves removing the first lymph node that cancer cells are likely to spread to.

3.3. Blood Tests

Blood tests can provide information about the presence of cancer in the body. They can detect tumor markers, which are substances released by cancer cells into the bloodstream.

• Tumor Markers: Tumor markers are proteins, enzymes, or other substances that are produced by cancer cells. Elevated levels of tumor markers in the blood can indicate the presence of cancer. Common tumor markers include:
  • CA 125: Elevated in ovarian cancer
  • PSA (Prostate-Specific Antigen): Elevated in prostate cancer
  • CEA (Carcinoembryonic Antigen): Elevated in colon cancer, lung cancer, and other cancers
  • CA 15-3: Elevated in breast cancer

3.4. Other Diagnostic Procedures

In addition to the above tests, other diagnostic procedures may be used to detect cancer metastasis, depending on the type of cancer and the suspected sites of spread.

• Bronchoscopy: A bronchoscopy involves inserting a thin, flexible tube with a camera into the airways to examine the lungs. It can be used to detect tumors in the lungs or to collect tissue samples for biopsy.
• Colonoscopy: A colonoscopy involves inserting a thin, flexible tube with a camera into the colon to examine the lining of the colon. It can be used to detect tumors in the colon or to collect tissue samples for biopsy.
• Endoscopy: An endoscopy involves inserting a thin, flexible tube with a camera into the esophagus, stomach, or duodenum to examine the lining of these organs. It can be used to detect tumors in these organs or to collect tissue samples for biopsy.

Alt text: Medical imaging techniques used to diagnose cancer metastasis.

4. What is the Role of the Lymphatic System in Cancer Spread?

The lymphatic system plays a significant role in cancer spread by providing a pathway for cancer cells to travel to distant sites; the lymphatic system is a network of vessels and tissues that helps remove waste and toxins from the body.

The lymphatic system is a crucial component of the immune system, responsible for maintaining fluid balance and transporting immune cells throughout the body. According to a review published in the journal “Cancer Research” in 2022, the lymphatic system also plays a significant role in cancer metastasis, providing a pathway for cancer cells to spread from the primary tumor to distant sites.

4.1. Lymphatic Vessels

Lymphatic vessels are thin-walled vessels that collect fluid and waste products from tissues and transport them to lymph nodes. Cancer cells can enter lymphatic vessels and travel to regional lymph nodes, which are the first sites of metastasis for many types of cancer.

4.2. Lymph Nodes

Lymph nodes are small, bean-shaped organs that filter lymph fluid and contain immune cells that can recognize and destroy cancer cells. When cancer cells enter a lymph node, they can form a new tumor, which can then spread to other lymph nodes or distant organs.

4.3. Lymphangiogenesis

Lymphangiogenesis is the formation of new lymphatic vessels. Cancer cells can stimulate lymphangiogenesis to create more pathways for metastasis. Factors secreted by cancer cells, such as vascular endothelial growth factor C (VEGF-C), can promote the growth of new lymphatic vessels.

4.4. Sentinel Lymph Node

The sentinel lymph node is the first lymph node to which cancer cells are likely to spread from the primary tumor. Identifying and removing the sentinel lymph node can help determine the extent of cancer spread and guide treatment decisions.

4.5. Lymphatic Metastasis

Lymphatic metastasis occurs when cancer cells spread to regional lymph nodes. The presence of cancer cells in lymph nodes indicates a higher risk of cancer recurrence and may require more aggressive treatment.

5. What is the Significance of “Seed and Soil” Theory in Cancer Metastasis?

The “seed and soil” theory suggests that cancer cells (the “seeds”) can only grow in certain organs (the “soil”) that provide a favorable environment; this theory helps explain why certain cancers tend to metastasize to specific organs.

The “seed and soil” theory, proposed by Stephen Paget in 1889, is a fundamental concept in cancer metastasis that explains why certain cancers tend to metastasize to specific organs. According to a review published in the journal “Nature Reviews Cancer” in 2023, this theory emphasizes the importance of the interaction between cancer cells (the “seeds”) and the microenvironment of the target organ (the “soil”) in determining the success of metastasis.

5.1. The “Seed” (Cancer Cells)

The “seed” refers to cancer cells that have detached from the primary tumor and are capable of spreading to distant sites. Cancer cells possess unique characteristics that allow them to survive in circulation, invade tissues, and form new tumors.

5.2. The “Soil” (Organ Microenvironment)

The “soil” refers to the microenvironment of the target organ, which includes the extracellular matrix, immune cells, blood vessels, and signaling molecules. The organ microenvironment can either promote or inhibit the growth of cancer cells, depending on its specific characteristics.

5.3. Favorable “Soil”

Certain organs provide a more favorable “soil” for cancer cells to grow and metastasize. These organs may have specific growth factors, nutrients, or immune cells that support the survival and proliferation of cancer cells.

5.4. Examples of “Seed and Soil” Interactions

• Breast Cancer and Bone Metastasis: Breast cancer cells often metastasize to bone because the bone microenvironment is rich in growth factors and minerals that promote their growth.
• Colon Cancer and Liver Metastasis: Colon cancer cells often metastasize to the liver because the liver receives a large blood supply from the gastrointestinal tract and contains growth factors that support their growth.
• Prostate Cancer and Bone Metastasis: Prostate cancer cells often metastasize to bone because the bone microenvironment contains hormones and growth factors that stimulate their growth.

Alt text: Diagram illustrating the seed and soil theory of cancer metastasis.

6. How Does Epithelial-Mesenchymal Transition (EMT) Contribute to Cancer Spread?

Epithelial-Mesenchymal Transition (EMT) is a process that allows cancer cells to become more mobile and invasive, facilitating their spread; EMT is a biological process where epithelial cells lose their cell polarity and cell-cell adhesion, and gain migratory and invasive properties to become mesenchymal stem cells.

Epithelial-Mesenchymal Transition (EMT) is a critical process in cancer metastasis that allows cancer cells to detach from the primary tumor, invade surrounding tissues, and spread to distant sites. According to a review published in the journal “Cell” in 2022, EMT involves a complex series of molecular and cellular changes that enable cancer cells to become more mobile and invasive.

6.1. Epithelial Cells

Epithelial cells are tightly connected cells that form the lining of organs and cavities in the body. They are characterized by strong cell-cell adhesion and a defined apical-basal polarity.

6.2. Mesenchymal Cells

Mesenchymal cells are motile cells that can migrate and invade tissues. They are characterized by a loss of cell-cell adhesion and an increased expression of mesenchymal markers.

6.3. EMT Process

During EMT, epithelial cells undergo a series of changes that transform them into mesenchymal cells. These changes include:

• Loss of Cell-Cell Adhesion: Epithelial cells lose their tight junctions and adherens junctions, which are responsible for cell-cell adhesion.
• Changes in Cell Morphology: Epithelial cells lose their defined shape and become more elongated and spindle-shaped.
• Increased Motility and Invasiveness: Epithelial cells gain the ability to migrate and invade surrounding tissues.
• Expression of Mesenchymal Markers: Epithelial cells start expressing mesenchymal markers such as vimentin, fibronectin, and N-cadherin.

6.4. Role of EMT in Cancer Metastasis

EMT plays a crucial role in cancer metastasis by allowing cancer cells to:

• Detach from the Primary Tumor: EMT enables cancer cells to break away from the primary tumor and invade surrounding tissues.
• Enter the Bloodstream: EMT facilitates the entry of cancer cells into the bloodstream, allowing them to travel to distant sites.
• Invade Distant Organs: EMT enables cancer cells to invade distant organs and form new tumors.

Alt text: Illustration of the Epithelial-Mesenchymal Transition (EMT) process in cancer.

7. How Can Understanding Cancer Spread Influence Treatment Strategies?

Understanding cancer spread helps doctors choose the most effective treatment strategies, such as surgery, radiation, chemotherapy, targeted therapy, and immunotherapy; understanding how cancer spreads throughout the body can guide the development of more effective treatments that target metastatic disease.

Understanding the mechanisms of cancer spread is essential for developing effective treatment strategies that can prevent or control metastasis. According to a report by the World Health Organization (WHO) in 2023, cancer is a leading cause of death worldwide, and metastasis is responsible for the majority of cancer-related deaths.

7.1. Surgery

Surgery is often used to remove the primary tumor and any regional lymph nodes that may contain cancer cells. Surgery can be curative if the cancer has not spread to distant sites.

7.2. Radiation Therapy

Radiation therapy uses high-energy rays to kill cancer cells. It can be used to treat the primary tumor or to target metastatic tumors in distant organs.

7.3. Chemotherapy

Chemotherapy uses drugs to kill cancer cells throughout the body. It can be used to treat metastatic cancer or to prevent cancer from spreading after surgery or radiation therapy.

7.4. Targeted Therapy

Targeted therapy uses drugs that target specific molecules or pathways involved in cancer growth and spread. It can be used to treat metastatic cancer or to prevent cancer from spreading.

7.5. Immunotherapy

Immunotherapy uses drugs that stimulate the body’s immune system to fight cancer cells. It can be used to treat metastatic cancer or to prevent cancer from spreading.

7.6. Personalized Medicine

Personalized medicine involves tailoring cancer treatment to the individual patient based on the characteristics of their cancer cells and their genetic makeup. This approach can help identify the most effective treatment strategies for each patient.

Alt text: Overview of different cancer treatment options available.

8. What are the Latest Research and Advancements in Preventing Cancer Metastasis?

Latest research focuses on developing new drugs and therapies that target the mechanisms of metastasis, such as EMT, angiogenesis, and immune evasion; research efforts aimed at preventing cancer metastasis are crucial for improving patient outcomes and reducing cancer-related deaths.

Recent advances in cancer research have led to the development of new strategies to prevent cancer metastasis. According to a report by the National Institutes of Health (NIH) in 2023, these strategies include:

8.1. Anti-EMT Therapies

Anti-EMT therapies target the EMT process, which is essential for cancer cells to detach from the primary tumor and invade surrounding tissues. These therapies aim to block the molecular pathways that drive EMT, such as the TGF-beta and Wnt signaling pathways.

8.2. Anti-Angiogenesis Therapies

Anti-angiogenesis therapies target the formation of new blood vessels, which are essential for tumor growth and metastasis. These therapies aim to block the action of vascular endothelial growth factor (VEGF), a key regulator of angiogenesis.

8.3. Immunotherapies

Immunotherapies stimulate the body’s immune system to fight cancer cells. These therapies aim to enhance the ability of immune cells to recognize and destroy cancer cells, including metastatic cells.

8.4. Metastasis Suppressor Genes

Metastasis suppressor genes are genes that inhibit the spread of cancer cells. Researchers are working to identify and characterize these genes and to develop therapies that can restore their function in cancer cells.

8.5. Nanotechnology

Nanotechnology is being used to develop new drug delivery systems that can target cancer cells more effectively and prevent metastasis. Nanoparticles can be designed to deliver drugs directly to cancer cells, minimizing the side effects on healthy tissues.

Alt text: Illustration of nanoparticles delivering drugs to cancer cells.

9. Can Lifestyle Choices Influence the Risk of Cancer Spread?

Yes, certain lifestyle choices, such as maintaining a healthy weight, exercising regularly, eating a balanced diet, and avoiding smoking, can potentially reduce the risk of cancer spread; adopting a healthy lifestyle can help boost the immune system and reduce inflammation, which may help prevent cancer metastasis.

Lifestyle choices can play a significant role in influencing the risk of cancer spread. According to a report by the American Cancer Society in 2023, certain lifestyle factors can help reduce the risk of cancer metastasis by boosting the immune system, reducing inflammation, and preventing DNA damage.

9.1. Healthy Weight

Maintaining a healthy weight can help reduce the risk of cancer metastasis. Obesity is associated with an increased risk of several types of cancer, including breast, colon, and endometrial cancer.

9.2. Regular Exercise

Regular exercise can help boost the immune system and reduce inflammation, which may help prevent cancer metastasis. Exercise can also help maintain a healthy weight and reduce the risk of obesity-related cancers.

9.3. Balanced Diet

Eating a balanced diet rich in fruits, vegetables, and whole grains can help reduce the risk of cancer metastasis. A healthy diet can provide the body with essential nutrients and antioxidants that can protect against DNA damage and boost the immune system.

9.4. Avoiding Smoking

Avoiding smoking is crucial for reducing the risk of cancer metastasis. Smoking is a major risk factor for lung cancer and several other types of cancer. It can damage DNA and weaken the immune system, making it easier for cancer cells to spread.

9.5. Limiting Alcohol Consumption

Limiting alcohol consumption can help reduce the risk of cancer metastasis. Excessive alcohol consumption is associated with an increased risk of several types of cancer, including breast, liver, and colon cancer.

10. What Support Services Are Available for Patients with Metastatic Cancer in Vietnam?

In Vietnam, patients with metastatic cancer can access various support services, including medical care, counseling, support groups, and palliative care; understanding the available support services can help patients and their families cope with the challenges of metastatic cancer.

Navigating a cancer diagnosis, especially metastatic cancer, can be overwhelming. It’s important to know that support is available.

10.1 Medical Care

Vietnam has a growing healthcare system with oncologists and specialists trained to treat metastatic cancer.

10.2. Counseling Services

Psychological support is available to help patients and families cope with the emotional challenges of cancer.

10.3. Support Groups

Connecting with others who understand what you’re going through can provide invaluable emotional support and practical advice.

10.4. Palliative Care

Palliative care focuses on relieving symptoms and improving quality of life for patients with serious illnesses. It’s available at many hospitals and can be a valuable resource for managing pain, fatigue, and other side effects of cancer treatment.

10.5. SIXT.VN Services

For those traveling to Vietnam for medical care, SIXT.VN can assist with transportation, accommodation, and other travel needs.

Navigating cancer metastasis can be overwhelming. Understanding the disease and available resources is essential for managing the condition and improving quality of life.

Address: 260 Cau Giay, Hanoi, Vietnam

Hotline/Whatsapp: +84 986 244 358

Website: SIXT.VN

Whether you’re planning a medical trip or simply seeking reliable information, SIXT.VN is here to support you.

By understanding how cancer spreads, we can work towards more effective treatments and preventative measures, ensuring a healthier future for everyone. When planning your trip to Vietnam, remember that SIXT.VN is here to assist with reliable and comfortable transportation, ensuring a stress-free experience.

Woman seeking medical care

Alt text: A woman receiving medical attention as part of cancer support services.

FAQs About Cancer Metastasis

1. Can cancer spread be stopped?

While not always curable, treatments can slow or stop the spread and manage symptoms.

2. What are the first signs of cancer spread?

Symptoms vary but can include persistent pain, unexplained weight loss, or fatigue.

3. Is metastatic cancer always terminal?

Not always; some patients live for many years with metastatic cancer, thanks to advancements in treatment.

4. How fast does cancer spread?

The rate of spread varies widely depending on the type of cancer, its aggressiveness, and individual factors.

5. Does early detection prevent cancer spread?

Early detection improves the chances of successful treatment and can prevent or slow the spread.

6. Can cancer spread be reversed?

In some cases, treatment can significantly reduce or eliminate metastatic tumors, but complete reversal is rare.

7. What role does genetics play in cancer spread?

Genetic mutations can influence the aggressiveness and spread of cancer.

8. Are there any alternative treatments for metastatic cancer?

Some patients use complementary therapies to manage symptoms, but these should be discussed with a doctor.

9. How does cancer spread affect life expectancy?

Metastatic cancer generally reduces life expectancy, but outcomes vary greatly.

10. What is the difference between local and distant cancer spread?

Local spread means cancer has invaded nearby tissues, while distant spread (metastasis) means it has reached distant organs.

SIXT.VN is dedicated to providing valuable information and support to travelers in Vietnam. Safe travels and good health!