Four good news in cancer treatment – 06/08/2023 – Health

Every year, tens of thousands of physicians gather in Chicago, United States, to learn about the latest in cancer diagnosis and treatment.

It is in this city that the Annual Meeting of the American Society of Clinical Oncology (Asco) takes place — and, after three years of virtual or hybrid panels due to the covid-19 pandemic, the sessions were once again face-to-face in 2023.

In this year’s edition, the scientific conference brought a series of good news and advances in the way medicine deals with different types of cancer.

Below, BBC News Brasil details the four main studies released during the event. They bring good news for the fight against lung, brain and rectum tumors and Hodgkin’s lymphoma – a type of cancer that affects cells of the defense system.

According to doctors who were at Asco 2023, these new studies have the potential to change the way patients affected by these diseases are treated.

LUNG CANCER: TARGETED THERAPY TO IMPROVE SURVIVAL

The drug osimertinib, from the pharmaceutical company AstraZeneca, has already been used for individuals with a specific type of lung cancer for three years.

But, at Asco 2023, researchers from the Yale Cancer Center, in the USA, were able to demonstrate that this drug is capable of extending the survival of patients who underwent surgery to remove the tumor.

According to the results, it reduces the risk of death by half when compared to a placebo (a substance with no therapeutic effect).

The authors of the study believe that the data reinforce the use of osimertinib as a standard treatment for these cases.

Oncologist William Nassib William Jr., leader of the thoracic tumors specialty at Grupo Oncoclínicas, explains that this medication is indicated for patients with non-small cell lung cancer —the most common type of disease in this organ— who have a mutation in a gene called EGFR.

When this tumor is diagnosed in its early stages, doctors usually do surgery to remove the affected lung tissue. But then there is always the question: is there any cancerous cell left at the site?

This is one of the main problems after the operation, as these microscopic tumor units can grow over time and reactivate the disease.

It is precisely to avoid this scenario that oncologists prescribe so-called adjuvant treatments. They try to eliminate these diseased cells, which cannot be removed surgically.

In the past, the main method used to make this kind of fine-tooth comb was chemotherapy. More recently, targeted therapies have emerged – such as osimertinib -which work like guided missiles and attack only specific tumor molecules.

The use of these more modern therapies, however, requires an examination that analyzes the genetic profile of the cancer and the mutations that occur there.

Osimertinib, for example, only works in individuals who carry the altered EGFR gene —which represents between 15% and 20% of all individuals with non-small cell lung cancer.

Results on this drug presented at Asco 2023 and published in scientific journals showed that 85% of patients who fit these criteria and took osimertinib survived for up to five years. In the placebo group, this rate was 73%.

“This reinforces the notion that this drug prevents those microscopic cancer cells from growing again, or perhaps even manages to eliminate them completely, which extends the survival time of patients”, analyzes William Jr.

The doctor observes that the most modern oncology drugs —such as targeted therapies and immunotherapies— are gradually starting to be tested (and approved) for the initial and less aggressive stages of the disease. Before, they were restricted to the advanced and complicated stages of the disease.

“With this, we will talk more and more not only about controlling these tumors, but even about curing them”, he anticipates.

Osimertinib is approved for use in Brazil by the National Health Surveillance Agency (Anvisa).

It is funded by health plans only for the most advanced cases of lung cancer. In the public network, the medication is not yet available.

GLIOMA: A NEW STRATEGY THAT DELAYS CHEMION

The brain is not just made of neurons: the organ responsible for memory and reasoning has glial cells, which are essential for the functioning and protection of the central nervous system.

The problem is that these units can also mutate and turn into a cancer. In that case, the disease is known as glioma.

And there is a type of it that has very particular characteristics. Low-grade glioma tends to be slow-moving and less aggressive—the patient often lives years or decades after diagnosis.

“Even so, it has a great impact due to the fact that it affects younger people, as it usually appears around the age of 20”, estimates physician Clarissa Baldotto, from the Committee on Tumors of the Central Nervous System of the Brazilian Society of Clinical Oncology ( SBOC).

This area of ​​medicine had not seen anything new for years – and the fact that the tumor develops in the brain, such a sensitive region, made it difficult to develop safe and effective therapies.

But that changed at Asco 2023 with the presentation of a study that evaluated vorasidenib, from the Servier laboratory, which is also a target therapy.

Researchers at Memorial Sloan Kettering Cancer Center, in the USA, showed that this drug reduces the risk of disease progression or death by 61%.

In addition, the new treatment still brings a second benefit. He postpones the need to resort to other more toxic resources (such as chemo and radiotherapy) to control the proliferation of cancer cells in the brain.

Avoiding this toxicity is even more relevant in the case of low-grade gliomas, since those most affected by the disease are young adults, who would suffer the side effects of these therapeutic resources for many decades.

Baldotto calls the study results “impressive”.

“The clinical trial further showed that this drug, taken once a day in pill form, is very well tolerated and has a low rate of side effects,” she adds.

As in the previous case of non-small cell lung cancer, the patient with glioma needs to undergo a test to assess which mutations the tumor has.

Vorasidenib works specifically when there is a change in the IDH1 and IDH2 genes.

For now, this drug is not yet available in Brazil for individuals affected by low-grade glioma.

RECTAL CANCER: THERE IS MORE THAN ONE WAY TO CURE

Within the universe of colorectal cancer (which affects the final stretch of the digestive system), tumors that originate in the rectum represent about a third of all cases.

“And, in recent years, we have made great advances in the treatment of this disease”, points out oncologist Virgílio Souza e Silva, from the ACCamargo Cancer Center, in São Paulo.

The latest big news in this area was announced during Asco 2023.

Scientists at Memorial Sloan Kettering Cancer Center have shown that two different therapeutic strategies are capable of achieving a similar result: a high survival rate and even cure after five years of starting treatment.

In the study, a portion of the volunteers with this locally advanced tumor, but without metastasis (when the diseased cells have spread to other parts of the body), underwent chemo and radiotherapy sessions. Another portion that had the same characteristics was submitted only to chemo.

Their results were then compared and showed a very similar positive effect: about 80% of participants in both groups were alive and disease-free within five years.

According to the authors, the possibility of offering more than one therapeutic path empowers patients, who can help in choosing the most comfortable and convenient option for them.

For Silva, the data presented “break paradigms established 20 years ago”, but do not mean that radiotherapy will be completely abandoned in these cases.

“Rectum cancer has a very complex treatment and we are increasingly able to have an individualized approach according to the case”, he says.

“Some individuals will continue to benefit from radiotherapy. For others, chemo alone will be enough”, he reinforces.

The oncologist believes that, among the main highlights of Asco 2023, this research is the one that has the most immediate impact on Brazilian public health.

After all, we are not talking here about incorporating new technologies. “This study tested therapies already available [sessões de químio e radioterapia]”, observes Silva.

And, as some individuals with rectal tumors will no longer need radiotherapy, this may even represent savings for the Unified Health System and a relief in the queues to use this resource.

HODGKIN’S LYMPHOMA: A STANDARDIZED TREATMENT FOR ALL AGES

This type of cancer affects some cells of the defense system and mainly affects young people, in the second or third decade of life.

In the more advanced stages of the disease, standard treatment involved chemotherapy sessions and a drug called brentuximab vedotin, from the pharmaceutical company Takeda.

Specialists from the City of Hope Medical Center, also in the USA, decided to propose a replacement for this scheme.

They tested whether brentuximab vedotin could be replaced by nivolumab (Bristol Myers Squibb), a type of immunotherapy, a pharmacological class that stimulates the patient’s own immune system to recognize and attack cancer cells.

Preliminary data from this study reveal that 94% of patients who received the new therapeutic regimen (nivolumab + chemo) were still alive within 12 months. Among those who followed the previous combination (brentuximab vedotin + chemo), this rate was 86%.

Another advantage of nivolumab was the greater tolerance of patients to side effects.

The authors themselves point out that it is necessary to observe the two groups for a longer period of time, but believe that the results obtained serve as a basis for modifying the way Hodgkin’s lymphoma is treated today.

Hematologist Guilherme Perini, from Hospital Israelita Albert Einstein, in São Paulo, classifies the study as “historical” and draws attention to another aspect: the work included younger volunteers, from 12 years of age.

“The research involved pediatric and adult patients. So far, the treatment of this disease was different according to age group”, he says.

“From now on, the tendency is for therapeutic protocols to be harmonized”, he adds.

Nivolumab is already approved by Anvisa and is used for the treatment of some types of tumors. It is funded by health plans and is available on the public network only for some specific indications, such as melanoma (a more aggressive type of skin cancer).

This text was originally published here.