He has professional interests in the field of solid tumor treatment according to modern international recommendations, using targeted and immunotherapy, as well as individualizing the medical approach to each individual patient and providing a multidisciplinary approach in their complex treatment. We are talking to Dr. Elise Tazimova about the current and concerning topic - new, gentle and effective cancer treatment.
Dr. Tazimova, what is neoadjuvant therapy in breast cancer?
- Neoadjuvant therapy is a drug therapeutic approach in patients with locally advanced malignant tumors. Medicines are applied as the first therapeutic strategy in order to reduce the size of the tumor, reduce the risk of distant metastasis and conduct subsequent organ-preserving surgical treatment to remove the tumor.
In diagnosed breast cancer, neoadjuvant therapy is recommended for tumors that are larger than 2 cm or have regional lymph nodes (axillary, intramammary, sub- and supraclavicular) involved by the process. The goal is to reduce the volume of the tumor, and it is even possible to achieve a complete impact on the tumor process.
When and in which patients is this type of therapy applied?
- This type of therapy has become established in recent years as a standard and recommended strategy, especially in patients diagnosed with locally advanced breast cancer, including a large primary tumor size and/or involved regional lymph nodes. It is also used in other solid tumors, such as urothelial carcinoma, stomach cancer, etc. Neoadjuvant therapy does not cancel the surgical removal of the tumor, but places it as a subsequent modality in the complex treatment of breast cancer patients.
Before conducting neoadjuvant drug therapy, several criteria must be met. These include a biopsy for histological verification, determination of hormonal and HER2 receptor status, determination of the proliferative activity index Ki67 and mandatory clarification of the final stage of the disease with imaging studies. With this information, the most recommended sequence of therapeutic modalities can be determined. And when it is judged that neoadjuvant therapy is necessary, it can be determined exactly what medicinal drugs to choose.
By what specialist and for what indications is this type of therapy prescribed?
- Modern local and international recommendations impose the need to draw up therapeutic strategies for patients with oncological diseases by a multidisciplinary team, including specialists from every field of medicine - from diagnosis to their treatment (medical oncologist, radiation therapist, surgeon, pathologist, imaging diagnostician, nuclear medicine physician, psychologist, social worker). Each of them is important in determining the most correct steps in the treatment process, since in most cases it is multi-level.
After discussing the characteristics of the disease in the respective patient – stage, receptor status, general condition, co-morbidities and preferences, the sequence of individual therapeutic modalities is determined. The neoadjuvant drug treatment itself is administered and monitored by a medical oncologist familiar with and following international standards for the treatment of this socially significant disease.
What is the duration of this type of therapy and what are the side effects for patients?
- Preoperative neoadjuvant drug therapy is administered for a period of 4 to 6 months. After a subsequent reassessment of the achieved effect, patients are referred for surgical treatment. Their strict follow-up is necessary, including regular physical local examinations. In case of imaging data showing that the neoadjuvant therapy does not affect the tumor process, a decision can be made to stop it prematurely and refer the patient to a surgeon.
The side effects of the medicinal drugs used - hormonal, chemotherapy, anti-HER2 therapy, do not differ in type, frequency and degree of manifestation from whether they are applied as neoadjuvant therapy, after surgical removal of the tumor or in metastatic stage. The drugs have a predictable and controllable toxicity profile in the hands of an experienced medical oncologist. Considering that with neoadjuvant therapy, one of our goals is to cure the patient and reduce the risk of distant metastasis, taking the supposed side effects is a worthwhile price.
What is the role of immunohistochemistry and its relation to the appointment of neoadjuvant therapy?
- Immunohistochemistry is an important and mandatory element in the diagnosis of breast cancer. It determines the expression of the hormone receptors for estrogen and progesterone and the overexpression of the HER2 receptor. These tumor characteristics define four main types: hormone-positive, HER2-positive (hormone-positive or negative, respectively), and triple-negative breast cancer. This determines the different aggressiveness of the tumor.
Like HER2 positive and triple negative, they have a more aggressive biology compared to hormone-positive breast cancer, with a different prognosis and corresponding use of different drug groups. The presence of aggressive characteristics of the tumor determines the need to apply neoadjuvant therapy to an even higher degree. In triple-negative breast cancer, chemotherapy is mainly used as drug therapy, including in the neoadjuvant aspect.
In HER2 positive disease, a whole drug group has been developed targeting this receptor in the form of monoclonal target molecules, drug conjugates and tyrosine kinase inhibitors, in combination with or without cytostatic treatment. While for hormone-positive variants we rely on endocrine/hormonal therapy and chemotherapy.
It is the knowledge of the immunohistochemical characteristics of breast cancer that gives us the basis for the most correct therapeutic and medicinal approach, from which we can demand and expect the greatest effectiveness and long-term benefit for the patient.
What does tumor clip marking, which is used in breast cancer, mean?
- Clip-marking is an approach in which, after the diagnosis of breast cancer, a marker is placed, which serves to mark the tumor formation and monitor the response from the neoadjuvant treatment. Clips should be placed immediately after histological confirmation of malignancy and before the first course of neoadjuvant therapy.
In patients with a significant reduction in size or complete effect and the absence of tumor from follow-up examinations, the initially placed clip helps the surgeon to determine the correct limits and volumes of the subsequent organ-sparing surgery and thus eliminates the need for a total mastectomy.
What are the advantages of neoadjuvant therapy?
- With neoadjuvant therapy, we have several goals. First of all, reduction of the tumor volume, which can help to carry out an organ-preserving operation afterwards, removing part of the breast, rather than the whole. Accordingly, the cosmetic defect is also improved.
With neoadjuvant therapy, the sensitivity of the tumor to the applied drugs and their effectiveness is tested. This also imposed a new end point in clinical trials, namely, the degree of pathological response after neoadjuvant therapy, which significantly determines the patient's long-term prognosis.
Last but not least, the aim is to prevent far spread, i.e. metastasis of the disease.
Timely applied, with correct and optimal drug regimens, neoadjuvant therapy can significantly improve the long-term prognosis of patients diagnosed with breast cancer and minimize the likelihood of recurrence and distant spread.