Cancer: innovations in prevention and treatment improving patients’ chances – BBC News Brasil

Dr. José Cláudio Casali da Rocha, head of oncogenetics at the ACCamargo Cancer Center, explains that genetic studies focused on cancer are divided into prevention and treatment, diagnosis and follow-up.

“The first (analysis) is called germline and is performed on the DNA of the person himself. The objective is to define the characteristics of individuals, detect a possible greater sensitivity of some genes to cancerous mutations and also genetic markers, for example. The analysis somatica is a genomic analysis of the tumor, done to evaluate the biological behavior of its cells and understand, among other factors, what are the chances that it will spread».

These genomic studies, according to Casali, require the creation of a therapeutic consensus among different specialists.

“Today, it is no longer a single doctor who defines the treatment. This decision is shared and discussed with the patient”.

The treatment is carried out with substances that have been developed to identify and attack specific characteristics of cancer cells, stopping the growth of the tumor and allowing the patient’s body to recover the conditions to defeat it.

The discovery of immunotherapy is what earned Japanese immunologists Tasuku Honjo and American James Allison the 2018 Nobel Prize in Physiology or Medicine.

Tests with these drugs have shown positive results for cancers such as breast, ovarian, lung, head and neck, bladder, melanoma, among others.

Even therapies using immunotherapy are proving increasingly effective, and this is good news for the coming years: the expectation is that the technique will become more popular in terms of knowledge and application, as well as cheaper.

In the Unified Health System (SUS), the first immunotherapy freely available to Brazilians was approved in 2020, benefiting patients with advanced melanoma.

Although many treatment options already exist, our public health system still faces obstacles due to financial problems.

Considered a type of immunotherapy, treatment with monoclonal antibodies, also called targeted therapy, helps the body identify cancer cells.

They are made in the laboratory to bind to a specific target on cancer cells and can trigger an immune response that destroys cancer cells or mark them, making them easier for the immune system to identify.

Antibody therapies can be combined with chemotherapy.

“What happens, in these cases, is that the combination will bring the chemotherapy directly to the cancer cell, focusing the treatment only on it, which reduces the toxicity to the body, while increasing the effectiveness of the treatment.” , says Carlos Barrios, an oncologist at Oncoclínicas and a hematology specialist at the University of Washington, USA.

According to him it is important to underline that, in order to obtain good results with these therapies, one factor is fundamental: knowing in depth the type of cancer and the characteristics of each patient and of each cell, in order to arrive at the disease more precisely.

“You need to be equipped with technology that identifies genetic alterations in detail. There are not many places that offer this type of treatment,” he says.

Fever, chills, weakness, headache, nausea, vomiting, diarrhea, low blood pressure, and skin rashes are some possible adverse effects of the technique.

A liquid biopsy is a test that uses primarily blood (although it can also use urine or other body fluids, such as saliva and cerebrospinal fluid) to look for cells from a malignant tumor or fragments of DNA from cancer cells.

“The test receives this name to differentiate it from the solid biopsy, in which a fragment of the tumor is taken and analyzed under the microscope, a more invasive technique,” explains Héber Salvador, oncological surgeon and president of the Brazilian Society of Surgical Oncology (SBC) .

For example, it is possible to evaluate the effectiveness of a treatment (such as chemotherapy), and the possibility of recurrence (return of the cancer) in a patient already in remission by analyzing the presence of cancer cells after the end of a treatment.

Although it is already used for other types of cancer, its most frequent current use is in patients with colorectal and lung cancer, as these are the diseases with the most research reinforcing the benefits of the technique.

A new therapeutic option for hematological cancers – such as lymphoma and leukemia – also applied through gene therapy, is the so-called CAR-T cell.

It consists of using the patient’s own cells (T lymphocytes, defense cells) and genetically modifying them in the laboratory to fight cancer.

With the technique it was possible to equip the body’s defense cells with receptors capable of recognizing the tumor and attacking it in a continuous and specific way.

The treatment’s high manufacturing cost is a cause for concern, but its progress has been encouraging since it gained popularity in Brazil in the second half of 2019.

At the time, a patient with advanced non-Hodgkins lymphoma at USP’s Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto, in the interior of São Paulo, was considered the first patient in Latin America to achieve disease remission with the use of CAR -T cells.

The strategy used for the treatment opens the door to its use not only in hematologic cancers – such as lymphoma – and can be used for any type of cancer.

“The methodology already includes research for acute myeloid leukemia and multiple myeloma protocols. It is expected that in the near future it will be possible to use CAR-T Cells in solid tumors, such as pancreatic cancer, just to name one of the possibilities that are already under discussion,” explains hematologist Renato Cunha, doctor at the Faculty of Medicine of the University of São Paulo (USP).