Tumor stage and spread
Tumors tend to spread and form further metastases. They spread to the surrounding lymph nodes or via the blood to distant organs. In patients with lung cancer, metastases are mainly found in the surrounding lymph nodes of the thorax as well as in the liver, brain, adrenal glands and skeleton, especially in the spine.
Based on the existing or non-existing infestation, different stages (=staging) can be determined, all of which have a different prognosis and are also treated differently. Small cell lung cancer can be divided into 2 stages: Since the tumor grows faster and more aggressively than a non-small cell lung tumor, this type of lung cancer has the worse prognosis. It grows very quickly, which makes early detection difficult.
Furthermore, the prognosis is worsened by an early spread with the formation of metastases. However, if the tumor is discovered in its limited stage, chemotherapy can bring about a cure in 5-10% of cases. These metastases often develop before the lung tumor is discovered.
For this reason, many tumors are often already outside the limited stage at the time of diagnosis and cannot be treated with the aim of cure. Possible therapies can only be applied with the aim of prolonging life and maintaining quality of life.Non-small cell lung tumors usually grow more slowly and later develop metastases. Their prognosis is therefore significantly better than that of small cell lung tumors.
The different stages are distinguished and determined on the basis of 3 parameters. The corresponding classification is the so-called TNM classification. This classification provides information on the prognosis and also determines the therapy.
In general, the prognosis worsens as the tumor progresses, i.e. when the numerical value of the TNM classification increases. For a tumor without lymph node involvement and distant metastasis (T0M0N0), the 5-year survival rate is given as 60%. If the tumor continues to grow (T2N0M0) the survival rate decreases to 40% after 5 years.
As soon as an affected lymph node on the same side as the lung tumor is added (T1/2N1M0) this chance decreases to 20%.
- Limited and
- Unlimited/extended (=unlimited) stage (=disease).
- Tmeans the size and extent of the tumor of the lung. Numbers are assigned from T1 (tumor <3cm) to T4 (tumor with infiltration of other surrounding structures).
- Nnumbers the extension to the surrounding lymph nodes. N0 (no lymph nodes affected) to N3 (various lymph node areas in the chest affected).
- The M gives information about the presence of distant metastases (mainly brain, liver, adrenal glands, skeleton). A distinction is made here between M0 (no distant metastases) and M1 (distant metastases present).
