Adjuvant therapy is referred to as supportive therapy. This treatment is a therapeutic measure that takes place following the surgical removal of the tumor. After the surgery, in most cases, tumor residual cells, known as circulating tumor cells (CTCs), remain in the body, as well as yet undetectable tumor nests or settlements (micro-metastases). Adjuvant therapy enhances the long-term prospects of healing.
Whether the number of CTCs remaining in the blood increases or decreases can be assessed and monitored using maintrac®. In addition to assessing the success of the therapy, pre-therapy medication tests can determine whether the medications planned for treatment actually affect the CTCs present in the blood or whether there are other substances that demonstrate a higher killing rate for CTCs.
The fundamental rule in an adjuvant therapy is:
- Decreasing cell count, the therapy is effective.
- Increasing cell count during therapy, consideration should be given to adjusting the therapy.
Behavior of CTCs in Adjuvant Therapy
Adjuvant chemotherapy typically consists of several treatment cycles at intervals of two to three weeks. The initial maintrac® cell count should take place approximately 2-3 weeks after surgery or just before the start of chemotherapy. A following CTC determination should be assessment after the second treatment cycle or just before the third cycle.
The initial measurement of the maintrac® cell count represents the baseline value, which alone has limited significance but the trend of cell counts from subsequent measurements can be interpreted.
Decreasing Cell Count
After the first 1-3 cycles, the number of CTCs in the blood decreases with a positive response to adjuvant therapy. If the cell count continues to decrease or remains low until the end of chemotherapy, this indicates a favorable disease course. Studies in non-metastatic breast cancer patients have shown that if the cell count decreases by a factor of ten, 90-95% of patients remain recurrence-free (without new tumors) after 4-5 years.
Even if CTCs in the blood have completely disappeared with a positive response, the therapy should still be completed. There might still be cells hiding in the tissue that could potentially be eliminated during the course of further treatment.
Steady Cell Count
The CTCs appear to have minimal response to chemotherapy. Furthermore, they seem to have only a slight growth tendency. In most cases, this is favorable for the disease course.
Increasing Cell Count
If the cell count continuously increases during adjuvant therapy or if it rises again after an initial drop in cell count at the beginning of treatment, the therapy is not effective or no longer effective. Unfortunately, the tumor cells are still active. The therapy should be adjusted in this case, as the prognosis for the further disease course is rather unfavorable. In this situation, maintrac® can test other medications that might be more effective. If non-metastatic breast cancer patients experience a continuous increase in cell count or a tenfold increase in cell count, 65-70% of patients experience a relapse within the first 4-5 years.