The fight against cancer: what treatments and advances do we currently have?

In the past week we saw how cancer attacks different organs and tissues of the body. When a cancer, replaces the space occupied by healthy cells with cancer cells, and by continuing to multiply, it causes serious disorders, and can also proliferate and mutate. For this reason, one of the most important advances in its treatment is early detection, which allows cancer cells to be attacked before they spread and become more difficult to combat.

Remarkable progress has recently been made in the early detection of cancerespecially in the identification of markers in blood, urine and stool tests, and the genetic analysis of biopsies. There are hundreds of clinical trials underway around the world testing new therapies, seeking to improve the standard of care and the ideal combination of treatments.

Success is not always defined as curing the patient, that is, leaving no trace of cancer cells. There are tumors that are inoperable, but in some cases, with treatment, their progress can be stopped. When the growth of a tumor stops, it is possible to live with cancer for many years. In those cases, success is defined not only in survival, but in the quality of life of the patient.

Treatments

Radiation, chemotherapy, surgery, and hormonal treatments are considered standard treatmentsthat is, scientifically verified as effective through rigorous experimentation, and whose side effects are known and acceptable.

The experimental ones are those that are undergoing medical experimentation, whose efficacy and side effects have not yet been tested in enough patients or diverse segments of the population to be clear about the possible results. All standard treatments were previously experimental and there was a lot of debate about when and how they should be applied, so experimentation always follows.

Adjuvant treatments are those that, added to the main one, enhance its effect. For example, Surgery may be followed by radiation or chemotherapy, to prevent cells that were not removed by surgery from growing back. A neoadjuvant treatment precedes the main therapy, and seeks to improve its efficacy. For example, by subjecting a tumor to radiation before removing it.

“Today [la radioterapia] uses instruments of a precision unthinkable when they began their use a century ago”.

In radiation therapy, ionizing radiation is used to kill tumor cells. Today it uses instruments of a precision unthinkable when they began their use a century ago.

The first use of radiation to cure cancer it was documented just 4 years after the discovery of X-rays by WK Röntgen (1895), and a year after Marie Curie discovered the radioactive elements radium and polonium. It was an extremely expensive system, until the discoveries made in developing the atomic bomb during World War II made the production of radioactive isotopes possible.

In the 1980s, radiotherapy relied on simple X-rays to locate the tumor, using 3D conformal radiotherapy (3DRT) and computed tomography (CAT), which made it possible to locate tumors more accurately. More techniques followed: magnetic resonance imaging (MRI), ultrasound (PET), and intensity-modulated radiation therapy (IMRT), which uses computer programs to control the intensity and focus of radiation. In this century, 4D radiotherapy, which protects healthy tissues by anticipating movement, and therapies with radioactive elements in the body to irradiate the tumor directly, are being perfected.

Advances and limitations

Chemotherapy to treat cancer It started around 1940. Although any drug can be named for using chemical substances for medicinal purposes, chemotherapy is the use of antineoplastic drugs administered orally or intravenously – more than 100 natural or synthetic substances – that stop the development of malignant tumors.

The design of targeted therapies or immunotherapy mitigated the problem of not distinguishing between healthy and cancerous cells, and their side effects.

Immunotherapy uses the body’s immune system to fight cancer cells. Activating the immune system dates back to the 19th century, when the physician William Coley (USA, 1862-1936), the father of immunotherapy, infected his patients with the virus ‘Streptococcus pyogenes’ to wake up your defenses and fight incurable sarcomas.

It was only in the 1960s and 1970s that it was discovered that Cytokines, small proteins responsible for intercellular communication in the immune system, can activate immune responses to attack cancer cells. Cancer cells have surface molecules (antigens) that can be recognized and used as targets for therapies.

In immune therapy, dendritic cell therapy, the patient’s blood cells are incubated with tumor antigens, activated, and reintroduced into the patient, inducing an immune response that attacks the tumor. There are therapies with antibodies and others with cytokines.

Complementary therapies are non-invasive treatments, which in combination with cancer treatment contribute to the physical, emotional and mental well-being of the patient. They are part of a comprehensive treatment, which includes them to allow the patient to cope with the treatments, reducing pain, nausea, anxiety and fatigue. There are also alternative therapies that reject and claim to replace traditional medicine. These can be very dangerous, as there is little or no scientific evidence of benefit, as has been the case with some supposed treatments against COVID-19.

The rush to find new treatments and cures is understandable, since even the accepted ones do not offer a guarantee and are not always available. Medicine advances at an impressive speed, but discoveries can take years to make results available to everyone.