Women with triple-negative breast cancer and high levels of immune cells in their tumors have a lower risk of recurrence after surgery, even without chemotherapy. This shows a study involving research at the University of Gothenburg.
Triple-negative breast cancer accounts for approximately 15% of all breast cancer diagnoses worldwide. Compared to other breast cancers, those affected are younger and more often of African-American, Hispanic, and Indian descent. In Sweden, about a thousand cases are diagnosed each year.
This type of cancer involves the absence of three so-called receptors, which reduces treatment options. Triple-negative breast cancer also grows faster and is more likely to spread, and recurrences occur more often than for other breast cancers after treatment.
The current study, published in the journal Jama, involves 12 research teams from three continents. Barbro Linderholm, Associate Professor of Oncology at the University of Gothenburg and Senior Physician at Sahlgrenska University Hospital, is in charge of the Swedish part.
Differences in survival rates
The study includes data from a total of 1,966 participants worldwide with triple-negative early-stage breast cancer. This means the tumors were small and had not spread. The patients had been treated with various combinations of surgery and radiation, but not chemotherapy.
The results show that the level of immune cells, tumor-infiltrating lymphocytes that can recognize and destroy cancer cells, was a strong prognostic biomarker, even when cytostatics were not part of the treatment. An important finding.
Five years after surgery, 95% of study participants whose tumor tissue samples from the breast tumor showed high levels of immune cells were alive. The survival rate in the group with low levels of immune cells was 82%.
Currently, the level of immune cells in tissue samples is not routinely measured or reported in triple-negative or other breast cancers, and highly demanding cytostatics are usually part of standard therapy.
Very good prognosis
According to the current health care program, the vast majority of patients with triple-negative breast cancer receive cytostatics, combined with surgery and radiation, even for small tumors, but our results show a very good prognosis for this group, even and without cytostatics. that have naturally increased levels of immune cells in tumors’.
Barbro Linderholm, Associate Professor of Oncology, University of Gothenburg
The study authors call for further research and clinical studies to investigate whether patients with a favorable prognosis, i.e. high levels of tumor-infiltrating lymphocytes in tumor tissue samples, could avoid intensive cytostatic therapy.
The method for assessing the ratio of immune cells is quick and cheap as it can be done in a regular pathology laboratory and it is not necessary to send samples for analysis.
“The findings from the study are not sufficient to translate into clinical practice, but this will now be investigated in an international prospective study where we will compare the prognosis of patients with high levels of immune cells in the breast tumor with and without cytostatics.” concludes Barbro Linderholm.
Source:
Journal Reference:
Leon-Ferre, RA, et al. (2024). Tumor-infiltrating lymphocytes in triple-negative breast cancer. GLASS. doi.org/10.1001/jama.2024.3056.