Breast cancer is one of the most prevalent and devastating diseases affecting women worldwide. Thanks to advances in medicine, it is now possible to diagnose and treat it more effectively, but there are still significant challenges in its management and in improving the quality of life of patients. To better understand the current situation, we spoke with Dr. Yann Izarzugazaan expert in Medical Oncology at the Jiménez Díaz Foundation University Hospital, who gives us a detailed overview of the types of breast cancer, advances in treatments, and the crucial importance of early diagnostic.
Dr. Izarzugaza explains how different types of breast cancer are classified according to the expression of certain proteins, and highlights recent advances in personalized treatments, which have significantly improved survival rates and reduced relapses in several subtypes of the disease. Furthermore, he provides us with insight into Innovations in diagnostic tests and surgical treatments available today, as well as the evolution of techniques to evaluate lymph node involvement.
Finally, we address the emotional impact that breast cancer has on patients and the importance of psychological support throughout the process. The combination of technological advances and a comprehensive approach to patient care is key to effectively confronting this disease.
Question: What are the most common types of breast cancer and how are they classified based on their origin and characteristics?
Answer: Within breast cancer, we study the expression of certain proteins, specifically estrogen receptors (both the estrogen and progesterone receptors) and the expression of the HER2 protein. Based on this, we classify tumors as tumors that are luminal, if they express hormone receptors, tumors of the HER2 subtype (which constitute more or less 20% of tumors) or triple negative tumors if they do not express even the estrogen receptor, neither that of progestrone, nor that of HER2. This classification allows us to make therapeutic decisions.
We also have molecular classifications, which arise from somewhat more complex studies at the laboratory level that allow us to have what we call the “intrinsic subtype”, with which we classify tumors into 4 groups: as Luminal A (less aggressive), Luminal B (more aggressive than luminal A), enriched in HER2 and basal tumors that usually correspond to the triple negative lineage by common pathological anatomy techniques.
Q: And what recent advances have been made in the treatment of breast cancer that we can highlight?
A: Well, in breast cancer, although unfortunately we still have relapse rates in patients with localized tumors that can reach up to 30%, great progress is being made in each of the subtypes.
In localized triple-negative tumors, combinations of chemotherapy associated with immunotherapy have significantly improved results. The appearance of PARP inhibitors has also allowed us to reduce relapses for a subgroup of tumors that have mutations in the BRCA genes.
There are also advances for those patients who have high-risk luminal tumors; We have seen that adding a drug, Abemaciclib, improves results to standard hormonal treatment.
And finally, for patients with HER2 tumors, in recent years we have the possibility of rescuing those patients who had residual disease from treatments that we call neoadjuvant (prior to surgery) with therapies directed at this target.
Dr. Yann Izarzugaza Perón, expert in Medical Oncology at the Jiménez Díaz Foundation University Hospital.
Q: Why is early diagnosis so important in breast cancer?
A: Early diagnosis of breast cancer is essential, because detecting a tumor when it is small and when there is no lymph node involvement is the most important thing when it comes to reducing the risk of a future recurrence.
Tumor staging, that is, tumor size and whether or not lymph nodes are affected, continues to be the main prognostic factor in breast cancer and in the majority of tumors.
Q:Are there any symptoms that could lead a person to suspect that they have breast cancer? Are there different symptoms depending on the types of tumor that you have explained to us?
A: When diagnosing localized breast cancer, the most common thing the patient may notice is a lump in the breast, or changes in the appearance of one breast in relation to the other: nipple retractions, asymmetries that were not there before, sometimes bleeding through the nipple can also be suggestive that there may be a problem in the breast. The main thing that patients usually see is a lump, a new nodularity in the breast.
Q: And what are the main or most important tests to diagnose breast cancer?
A: Today, the primary test continues to be mammography, which allows us to make very early diagnoses. It allows detecting microcalcifications and often tumors that are not yet infiltrating. These mammograms have been improving and now we have options to do digital mammograms, with newer radiodiagnostic equipment and even do mammograms with contrast.
We have other imaging techniques such as breast ultrasound, which usually provides support to mammography when we have very dense breasts, which usually occurs in young women. And finally, we have MRI, which is a test that is very sensitive but not very specific. That is to say, many images can be suspicious in MRI, so we usually reserve it for those cases in which we have a high suspicion or in which we already have a confirmed diagnosis and when we want, before operating, to make sure that there are no more injuries.
Q: Speaking of operations, what types of surgical treatments are there today and how have they changed in recent years?
A: As for surgery, we basically have two options. Either conservative surgery (and associated radiotherapy), in which we remove only the tumor and take more space to ensure that the edges are not affected. And the other alternative is to perform a more radical mastectomy and remove the entire breast. This has to be done when there is multicentricity, multiple foci in the breast, or when the tumor is very large. We choose this mastectomy technique if there are other genetic risk factors that indicate a high risk of a new tumor during the patient’s life.
There have been many improvements in the study of the sentinel node. In the past, we used to do a lot of axillary dissections (removing all the lymph nodes in the armpit), and now, with sentinel node techniques and with the adoption of new molecular biology tools and genomic tests, we often have enough information by only removing one sentinel node. We reserve axillary dissection for specific cases.
Q:How does treatment affect patients emotionally and what support is offered?
A: In breast cancer, when both surgery and systemic treatments, whether chemotherapy or hormones, have to be used, there is an impact both psychologically and socially. At multiple levels. In this problem, at the hospital level, we still have a long way to go. Hospitals usually have support from psycho-oncology clinics that provide support to patients both individually and in groups. In addition, there is also a lot of support from patient associations, but it is clear that this help is in great demand and we must strive to improve it.