At the 55th edition of ASCO (American Society of Clinical Oncology), held in Chicago in early June, nearly 5,000 papers were presented. Here are the most significant medical advances in advanced or aggressive forms of cancer.
Breast cancer: promising innovative treatments
The number of women affected by breast cancer is increasing. the hormone-dependent cancer (that is, sensitive to hormones) is one of the most common. Patients usually receive treatment aimed at blocking the production of estrogen. The MONALEESA-7 study tested in a metastatic situation a ttargeted therapy, the ribociclib (Kisqali), in women under 59 years of age whose disease began before or during menopause. This molecule, less toxic than chemotherapy, specifically targets cancer cells and prevents them from multiplying. Coupled with standard treatment, it has made it possible, at an advanced stage of cancer, to improve the survival rate by up to 70% after a follow-up of 3 and a half years.
Another result: this time it concerns so-called “triple negative” breast cancers (15% of breast cancers in France) whose treatment is complex, because they are not sensitive to anti-hormonal treatments or targeted therapies. “Their management, beyond surgery, is based on chemotherapy protocols, but resistance mechanisms are an obstacle to lasting remission”, underlines Dr Olivier Tredan, oncologist at the Léon Bérard center in Lyon. Immunotherapy, which aims to boost the patient’s immune system to allow it to destroy cancer cells, raises new hopes. The IMpassion 130 study showed thatatezolizumab (Tecentriq), in combination with paclitaxel-based chemotherapy increases patient survival whose tumor significantly expresses the PD-L1 protein, involved in the weakening of their immune system.
Lung cancer: lasting results with immunotherapy
It is now cancer that causes the most deaths in men and also in women. “In the absence of organized screening, 60 to 70% of patients are diagnosed at an advanced stage, underlines Pr Nicolas Girard, thoracic oncologist at the Institut Curie (Paris), specifying that the National Cancer Institute (INCa) works with learned societies on its deployment. At metastatic stage, chemotherapy only works in a third of patients. For others, in a situationtherapeutic dead end, the’arrival of immunotherapy, which helps patients’ immune systems fight cancer, was a game-changer. “
” Thanks to the’immunotherapy, some patients are now living longer. It is also given as the first line of treatment, as a replacement for chemotherapy, provided that the cancer cells strongly express the PD-L1 protein, which represents approximately a third of the cases ”, continues the professor.
The Keynote-001 study presented to ASCO showed that nearly a quarter of patients with a, who took pembrolizumab (Keytruda), without having undergone chemotherapy before, were alive after five years. Results never achieved before. “The fact that patients participating in this trial are still alive after 7 years is quite remarkable,” said Edward B. Garon, professor of medicine at the University of California, responsible for the study.
Pancreatic cancer: finally a new therapy for some patients
Due to an often late diagnosis, the prognosis for pancreatic cancer is one of the bleakest. Currently, there are around 14,000 new cases per year. A new targeted therapeutic approach appears promising: in the POLO clinical trial, patients had metastatic cancer that had not progressed after 16 weeks of platinum-based chemotherapy and carriers of a constitutional mutation of the BRCA gene. “After chemotherapy, they took olaparib (Lynparza), a targeted treatment which exploits a weakness in the capacity of cancer cells carrying BRCA mutations to repair DNA damage, ”explains Dr Cindy Neuzillet, digestive oncologist at the Institut Curie in Saint-Cloud.
After 2 years, 22.1% of patients receiving olaparib had no disease progression compared to 9.6% of those treated with placebo.
“This is the first time thattargeted therapy has effects on pancreatic cancer and helps control the disease. Admittedly, these results concern only patients carrying a particular genetic mutation, but they are encouraging, estimates Dr. Neuzillet. The duration of response to treatment can be up to two years, which has never been seen before. “
Childhood cancers: the first targeted therapies in solid tumors
Today, more than 80% of children with cancer can be cured. “A lot of progress was made between the 1970s and 1990s, but since then progress has been slower,” underlines Professor François Doz, pediatric oncologist at the Institut Curie in Paris. If we have succeeded in reducing the toxicity of treatments, our challenge is toincrease the chances of recovery from rare pediatric cancers, but with a poor prognosis. “
Two clinical trials presented to ASCO are hopeful: for the first time, targeted therapies, targeting genomic alterations that can occur in cancers, have been tested in children and adolescents with encouraging results. “This is theentrectinib and larotrectinib that target an alteration found in a wide range of types of solid tumors (the NTRK fusion), regardless of their location in the body, ”says Prof. Doz. The first molecule was given for tumrecurring solid owers and refractory to treatment or central nervous system cancers, the second for ssoft tissue arcomas rdrug resistant.
“In the United States, the larotrectinib is already authorized in adults and children for the treatment of tumors with NTRK fusion. In France, pending marketing authorization, the drug is available as part of a temporary authorization for cohort use, ”explains Prof. Gilles Vassal, director of clinical research at Gustave Roussy, in Villejuif. These first efficacy results only concern a minority of sick children since pediatric cancers with such an alteration are rare.
“But they pave the way for so-called“ precision ”medicine in children. This therapeutic approach, requiring characterize tumors by genetic sequencing, makes it possible to offer targeted therapies in a situation of therapeutic failure, ”says Professor Vassal.