Histological grading
Apart from important prognostic factors such as lymph node involvement and receptor status of the tumor, histological grading also plays an important role. Under the microscope, the cells of the tumour are assessed from a tissue sample of the breast and the grading is determined on the basis of this. Tumours whose cells closely resemble the tissue of origin are called G1 tumours.
A strong similarity to healthy breast tissue is prognostically favourable. Such tumours can be classified in the low-risk group if they meet further favourable criteria. They do not require particularly aggressive tumour therapy and have better chances of survival and healing.
The probability of a relapse is also lower than for tumours in the high-risk group. A G2-grading means that the tumour is already less differentiated and differs more in its structure from the original breast tissue. Such tumours are usually more aggressive and malignant.
They are therefore associated with a higher risk of metastasis. Such tumours are classified in a higher risk group than G1 tumours. However, a tumour with a G2-grading does not necessarily have to be associated with worse survival and healing chances than a tumour with a G1 differentiation.
Other factors such as lymph node metastases and the receptor status of the tumour are decisive. The grading of breast cancer plays, among other factors, an important role in the prognosis of women. A breast tumour that receives G3 grading shows poorly differentiated tissue under the microscope.
This means that the tissue of the tumour is very different from the original tissue of the breast. G3 grading is therefore considered to have an unfavourable prognosis. The chances of healing therefore appear to be worse at first than with a tumour of a better grading.
However, this is not always the case. Much more important than tumor grading are factors such as response to therapy or metastasis. Tumours that are not metastasised have a better prognosis even with a higher grade than those that have a low grade and are metastasised. Therefore, the chances of cure cannot be determined on the basis of the grading alone.
Hormone dependence increases chances of cure
The hormone dependence of breast cancer can also be decisive for the prognosis of the disease. Hormone dependence means that the cancer is stimulated to grow by female sex hormones (estrogens). With specially developed drugs it is possible to suppress the effect of oestrogen on the cancer cells and thus prevent the disease from progressing.
A hormone dependence of breast cancer can therefore have a positive effect on the survival rate and chance of recovery through this further therapeutic option. In addition, hormone-dependent tumours rarely form metastases. However, the relapse rate (recurrence rate) is significantly higher in women who develop breast cancer before the age of 35, i.e. they develop breast cancer again more frequently in their later life.
Although hormone-independent breast cancer grows more aggressively, if it is completely removed, relapses are less frequent. The prognosis therefore depends on the individual case. At a higher age, however, the prognosis for hormone-dependent breast cancer is better than for hormone-independent breast cancer.
