Investigations in confirmed breast cancer
If it is certain that a woman has breast cancer, further investigations will follow. They should show if and if so, how far the cancer has spread in the body. For example, an X-ray examination of the chest (chest X-ray ) can detect secondary tumors in the lungs (lung metastases). Deposits in the liver can often be detected by means of ultrasound. A nuclear medicine examination of the bones ( bone scintigraphy ) can show whether cancer cells have settled in the skeleton. A computed tomography (CT) can be helpful in finding metastases.
The pathological finding
On the basis of the different examination results a pathological result is created. In it, the characteristics of breast cancer are recorded as accurately as possible, usually in the form of abbreviations.
For example, the TNM name indicates …
… how big the tumor is (T1 to T4),
whether adjacent (regional) lymph nodes are affected (N0 to N3) and
whether the breast cancer has already formed (distant) metastases in other body regions (yes = M1, no = M0).
For example: T4N3M0 indicates a large tumor that has invaded surrounding tissue (T4), scattered cancer cells (N3) in many lymph nodes, but has not yet formed distant metastases (M0).
Further abbreviations before the TNM designation provide additional information. For example, a prefixed “c” indicates that the TNM classification is based on the results of the imaging study. By contrast, in the case of a prefixed “p” , the classification is based on the findings of the histological examination of the tissue sample.
Also important for the classification of breast cancer stages is the “grading” – the degree of degeneration of the tumor. It comprises four stages: from G1 (tumor still well differentiated, slow-growing, less aggressive) to G4 (undifferentiated tumor, fast-growing, tends to grow aggressively into surrounding tissue).
The pathological findings also indicate the hormone receptor status of the tumor , ie whether the patient’s breast cancer has many docking sites for estrogen (ER + or ER-positive) and / or progesterone (PgR + or PgR-positive). This is important for therapy planning: In a tumor with many hormone receptors, a corresponding hormone withdrawal can slow down tumor growth.
Also recorded is the HER2 receptor status , ie whether the tumor cells have many docking sites for growth factors on their surface. If so (HER2 positive), the disease usually takes a more aggressive course. With special therapies that block the HER2 receptors, one can try to prevent breast cancer from growing.
Unsuitable for diagnosis: tumor marker
Breast cancer can not be diagnosed by tumor markers in the blood , as previously hoped . Tumor markers are proteins whose concentration in the blood or tissue may be elevated in cancer – either because they are produced by the tumor itself or by healthy cells in response to the tumor in larger quantities.
However, other diseases can often increase the concentration of such tumor markers. Therefore, they are usually not suitable for diagnosing cancer. With their help, however, one can assess the course of a cancer and the success of the therapy . This also applies to breast cancer: The most important tumor marker in breast cancer is the CA 15-3 ; Also CEA plays a role. Both tumor markers are repeatedly measured in breast cancer patients to examine how the tumor develops and how well the treatment works.