Healing Now


It’s so transforming. Cancer patients & survivors can feel better and live longer using powerful strategies. Explore how I help as a Cancer Coach, writer, consultant & speaker.

Get my Top 10 Integrative Cancer Care Strategies e-book, 
inspired articles, and insights delivered to your inbox.

Home  /  Integrative Cancer Care  /  Body  /  Whole Body Cancer Care and Cancer Prevention  /  Immune System and Cancer

Immune System and Cancer

By Jeannine Walston


What is the immune system? What is the relationship between the immune system and cancer?

The immune system is a body wide integrated network of cells, tissues, and organs that works to safeguard health. At the core of the immune system is the ability to differentiate between self and non-self. The immune system is designed to defend the body against attacks by foreign or non-self invaders. However, the immune system does not always recognize cancer cells as foreign antigens or non-self. Therefore, cancer may develop when the immune system breaks down or does not function adequately in the recognition of foreign antigen invaders.

“A healthy immune system can quickly and easily identify foreign cells. In the case of cancer, a cell that is dividing abnormally and showing other unnatural signs can be identified and tagged just like a genuinely foreign cell. Theoretically, a healthy immune system can destroy cancerous cells before they get a chance to multiply and become dangerous. We all have cancer cells circulating in our bodies all the time, and yet not everyone develops cancer. When cancer does not develop, it is because the cancer cells are disorganized, uncoordinated, and spread out, making them easily defeated by a strong, organized, well-fed, and well-rested immune army. Sometimes, however, the cancer is stronger and more organized than the immune system and can evade the immune response.

Not that long ago, cancer was thought to be simply an immune deficiency. If a person got cancer, it was believed to be caused by a weakened immune system that allowed the cancer to develop and spread. While decreased immunity is certainly a contributing factor, we now know that cancer is not merely the result of immune deficiency. In fact, a fast-growing cancer can coexist with a strong immune system. As cancerous tumors grow, they can develop features that camouflage them from the immune system’s surveillance. Cancer can also scramble the messages between immune cells and even send out its own messages in the form of cytokines that confuse the immune system and prevent it from responding effectively. However, despite these cunning tactics, the influence and the power that a healthy immune system has on cancer cannot be underestimated.”
-Lise Alschuler, ND, and Karolyn Gazella, The Definitive Guide to Cancer

What are some of the major immune system organs and cells?

Major Immune System Organs

Bone Marrow—soft tissue in the hollow center of bones that is the ultimate source of all blood cells. Bone marrow-derived stem cells undergo a process of differentiation into either mature cells of the immune system or precursors of cells that leave the bone marrow to mature elsewhere.

Thymus—master gland of immunity that receives cells from the bone marrow, filter unhealthy cells, and produce mature T cells that are released into the bloodstream.

Spleen—a central command center for the immune response filtering the blood and lymphatic system of cell debris, microorganisms, and old or damaged cells. The spleen manufactures lymphocytes and traps foreign antigens to initiate the B cells response.

Lymphatic System and Lymph Nodes—organs of the immune system are connected with one another and with other organs of the body by a network of lymphatic vessels carrying lymph, a clear fluid that bathes the body’s tissues. Small, bean-shaped lymph nodes sit along the lymphatic vessels with clusters in the neck, armpits, abdomen, and groin. Each lymph node contains specialized compartments where immune cells congregate and encounter antigens. Immune cells and foreign particles enter the lymph nodes through incoming lymphatic vessels or the lymph nodes’ tiny blood vessels. All lymphocytes exit lymph nodes through outgoing lymphatic vessels.

Once in the bloodstream, they are transported to tissues throughout the body patrolling everywhere for foreign antigens and then gradually drifting back into the lymphatic system to begin the cycle again.

Major Immune System Cells

T Cells—orchestrate immune response through many types of T cells with specialized functions. Studies suggest that low T cells correlate with lower survival in people with cancer.

B Cells—produce antibodies matched to specific antigens with the goal of identifying and marking the antigens for action by other immune cells throughout the body.

Natural Killer Cells—destroy cancer cells and cells infected with viruses through releasing toxic substances directly into cells.

Phagocytes—including monocytes, macrophages, dendritic cells, and neutrophils, help identify antigens to organize a body wide defense as well as engulf and consume foreign invaders.

What strengthens the immune system?

Many integrative cancer care components strengthen the immune system. Some immune support strategies include nutrition, anti-inflammationdetoxification, sleep, approaches within our section Integrative Cancer Medicine Systems such as functional medicineherbal medicine, naturopathy, and Traditional Chinese Medicine, specific cancer vitamins, supplements and herbs, acupuncture, mind-body practices, spiritual support, social connections, clean non-toxic products, as well as many other strategies, approaches, and therapies.

What are the potential benefits of therapies to strengthen the immune system?

  • Supports anti-cancer activity
  • Reduces side effects from other cancer treatments
  • Improves quality of life

What weakens the immune system?

Infectious organisms such as bacteria, viruses, toxins, fungi, and parasites attack and compromise the immune system. Some other factors that weaken the immune system include cancer cells, poor diet, no exercise, stress, inadequate sleep, overweight or obesity, pollution and other environmental toxins, some medications, alcohol, smoking, trauma, aging, radiation, and some conventional cancer treatments.