One of the most difficult diseases to treat is the all-encompassing category of Cancer. Heart disease, diabetes, pulmonary defects, vitamin deficiencies, even some auto-immune diseases have given up some or most of their secrets: their causes and their chemical, metabolic, or physiologic derangements. And specific therapies can address or correct these abnormalities. But cancer defies description. Without an understanding of its cause or basic cellular or metabolic derangement, specific therapies cannot be designed to target the causes or specific derangements.
Therefore, the treatment of cancer has been pragmatic: cut it out if it’s a solid tumor, stamp it out with chemicals if it’s a blood cancer, or poison it with chemicals or burn it with radiation if it’s inoperable.
Operations have to be very carefully delineated to remove only the tumor but not healthy tissue. However, cancer can be enmeshed in the healthy tissue (like pancreatic cancer) or hidden in deep recesses of the body (like brain tumors and eye tumors) making surgical removal impossible.
Because cancer cells are so similar to healthy tissue, finding chemotherapies that destroy cancerous cells but not healthy cells is extremely difficult. Because cancers grow rapidly, chemotherapies are designed to target rapidly growing cells. But many cells of the body rapidly grow: red cells of the blood, white cells of bone marrow and other immune system organs (i.e., spleen, liver, lung), the hair/nails of the skin, and the lining of the gut. Therefore, these chemotherapies cause all too familiar side effects that become the common experience of cancer patients undergoing chemotherapy – and their families.
Radiation that destroys the cellular structure of cancer cells, also destroys cells of other tissues through which the radiation passes getting to cancer cells. When radiation is focused on a cancer target from several directions, the damage to cancer cells can be much greater with lesser damage to surrounding healthy tissue. But damage is still a major limiting effect of radiation.
In the last 40 years, advancements have been made fighting against the elusive monster of cancer. White cells – the soldiers of the body – are designed to find and destroy foreign invaders: bacteria, viruses, fungi, and cancers. These invaders have proteins on the surface of their cells not usually found in the human body. White B-cells attach chemicals called antibodies to the
foreign proteins to form antigens that attract white T-cells The T-cells, using these antigens as
“handles,” attach to these “marked” cancer cells and destroy them.
But cancer cells being so similar to healthy cells, white cells have difficulty in recognizing cancer cells as invaders. Advances in immunology – recognizing how “invader-ism” works – have given rise to more targeted immune markers that have been extremely effective in some blood cancers.
One of the newest therapies is Chimeric Antigen Receptor-T cell – CAR-T cell therapy. Basically, the patient’s T-cells are collected and subjected to genetic modification by adding a gene to the T-cell’s DNA. These modified CAR-T cells now recognize the “foreign” proteins on the cancer cell surface, attach to these “handles,” and destroy them. This modality has been especially effective in chronic lymphocytic leukemia, B-cell non-Hodgkin lymphoma, and multiple myeloma. This therapy is currently being adapted to other blood cancers and other easy-to-reach solid tumors.
Theranostics (or theragnostics) – another field of advancing cancer therapy – pairs two tools of diagnosis and treatment into a team therapy approach. The growing field of diagnostic imaging, like CT, MRI, PET scans, SPECT scans, creates pictures and 3-D images that determine the specific size, shape, and location of cancers. Then, radiation “seeds” are placed next to the cancer on multiple sides that irradiate the tumor but cause minimal damage to surrounding tissues. Or, external ionizing radiation of various types are more accurately focused from multiple directions from outside the body (exposing “pass through” tissues to much less radiation) to target cancer cells with high levels of radiation. This therapy is especially effective in cancers inside an organ – like the prostate – before the cancer metastasizes into the rest of the body.
A third cancer treatment especially for hard-to-treat brain cancer is Boron Neutron Capture Therapy (BNCT). For 75 years, this therapy has been only theoretical, specifically to place the element boron inside cancerous brain cells. Boron loves to collect stray neutrons into its atomic structure. This modified boron breaks down into helium and lithium which destroys the cancer cell. Investigative chemists are making advances in how best to insert boron into the cancerous brain cells only, not into healthy cells. When a stream of neutron radiation is aimed at the brain, the neutrons are taken up only in the cancer cells and they are destroyed. Not yet practical, this is the new horizon of brain cancer treatment.
If you should develop the need for cancer therapy, ask your physician if any of these therapies is applicable to your case. You could become part of a study or trial that could save your life.
