June 15, 2023 – Sometimes less is more, and researchers are increasingly on the lookout for ways to securely “de-escalate” cancer therapy, that's, make a patient's treatment less aggressive without compromising their probabilities of survival. A recent study shows that girls with early-stage HER2-positive breast cancer might be successfully treated without Chemotherapy and thus avoiding its serious unwanted side effects.
HER2-positive breast cancer just isn't as common, being diagnosed in about 1 in 5 breast cancer patients. This implies that the cancer cells have extra copies of the gene that produces the HER2 protein, and such a cancer tends to be more aggressive than others.
However, a treatment has been developed that specifically targets HER2-positive breast cancer. Trastuzumab and pertuzumab goal the HER2 protein, and these two drugs are generally used together with conventional chemotherapy before and after surgery.
However, the present study, recently presented on the annual meeting of the American Society of Clinical Oncology in Chicago, showed that some women can forgo chemotherapy.
Better quality of life
“The introduction of anti-HER2-based therapy has dramatically changed the prognosis not only of HER2-positive metastatic breast cancer, but also of HER2-positive early-stage breast cancer,” said study creator Javier Cortés, MD, PhD, of the Ramón y Cajal University Hospital in Madrid, Spain. “And this has opened the possibility of investigating different de-escalation strategies.”
In this study, Cortes and his team divided 356 patients over 18 years of age with operable HER2+ early-stage breast cancer into two groups, A and B.
The women in group A received a mix of chemotherapy and trastuzumab and pertuzumab. In contrast, the treatment in group B was designed in order that chemotherapy might be disbursed with depending on individual progress.
After participants in group B received two cycles of pertuzumab and trastuzumab, they underwent positron emission tomography (PET) scans. If the scan showed that they'd responded to treatment, they underwent further rounds of treatment, but without chemotherapy.
Both groups underwent surgery after their initial therapy. After surgery, the patients who showed no signs of cancer continued their treatment without chemotherapy. The remaining patients received chemotherapy.
All of the patients within the study responded thoroughly to treatment. About 95% of patients were cancer-free after three years, and that number was even higher within the group that didn't receive chemotherapy. Cortes found that in those 30% of patients, principally one in three patients who didn't receive chemotherapy, the three-year relapse-free survival rate was excellent at almost 99%.
“In my opinion, this study could identify 30 percent of patients who may be cured without chemotherapy and only need to be treated with a combination of trastuzumab, pertuzumab and, if appropriate, endocrine therapy,” Cortes said.
He also identified that the speed of significant unwanted side effects was significantly lower in patients who were capable of avoid chemotherapy.
“What we saw in this study was that there was clearly a benefit in terms of side effects,” said Justin M. Balko, PharmD, PhD, of Vanderbilt University Medical Center in Nashville, Tennessee, who commented on the study in the course of the meeting. “As someone who studies immune-related side effects in his own lab, I thought that while this was not unexpected, it was really impressive to see the data showing how much more likely the quality of life was for these patients who were rescued or spared from chemotherapy.”