TNM system

All information given here is only of a general nature, tumor therapy always belongs in the hands of an experienced oncologist!

Synonyms

TMN classification

English: TNM Classifications of malignent tumors

introduction

The TNM system, also TNM classification (engl. TNM Classifications of malignent tumors) is used for classification malignant tumors. (Cancer diseases). With the help of this classification, the various cancers can be uniformly classified worldwide according to their severity and assigned to corresponding treatment guidelines.

history

The TNM system was founded between 1943 and 1952 by the French Pierre Denoix developed. Since 1950 it has been owned by the international union international contre le cancer (UICC for short) further developed. Today the TNM system is recognized and used by most countries in the world, and the cancer registry also uses the TNM system. It is based on studies and statistical data on behavior and the Malignant Cancer Forecast. Accordingly, it is used in most countries for the prognosis and therapy of the disease.

General

The Abbreviation TNM (TNM system) describes the spread of the tumor in the body. This is where it stands "T" for the Primary tumor and its Size, spread and invasiveness. The letter "N" denotes the Number of lymph nodes involved (engl = nodes). With the letter "M" will the Metastases designated. This is all about the presence or absence of distant metastases, not their number or which organs are affected.
Basically, a number is added after each letter. It stands 0 usually for one Absence of the corresponding tumor infestation, while increasing numbers represent an increasingly dangerous tumor condition. If the tumor has been examined histologically by a pathologist, a "P" marked before classification. Is the tumor classified clinically or surgically a "C" placed in front of the TNM classification (TNM system). It can thus be distinguished whether the classification is only secured macroscopically or microscopically. More details are explained below under the individual components of the TNM system.

T = tumor

T0:
This means that no primary tumor is visible. At first glance, that doesn't make much sense. This term is used, however, when a tumor is before an operation chemotherapy and has receded to such an extent that it is no longer macroscopically visible. However, there are usually still tumor cells in the tissue that have to be surgically removed. In other cases the primary tumor is unknown. This can happen if there are too many metastases and the primary tumor has not yet been precisely determined. Such a clinical picture is called CUP syndrome designated (Cancer of unknown primary).
Tis / Ta:
These are tumors rolled into one very early stage of the disease. They have not yet infiltrated the basement membrane, so they have not yet penetrated far into the tissue. Your prognosis is usually favorable. However, due to the very low spread, it is difficult to diagnose. Usually these are incidental findings during routine examinations. Ta tumors only exist in certain organs (urethra, Renal pelvis, ureter, bladder and penis). There Ta tumors can have a better prognosis than Tis tumors.
T 1,2,3 or 4:
The increasing number indicates the increase in size of the primary tumor and the infestation of the neighboring organs. Since the ways in which the individual types of tumor spread differ, the increase in size and invasiveness is illustrated here using the example of breast cancer:

• T1: largest tumor extension no more than 2 cm
• T2: Tumor extension at least 2 cm, but not more than 5 cm
• T3: largest tumor extension more than 5 cm, but no spread to the neighboring organs.
• T4: All tumors larger than 5 cm with spread to the chest wall or skin.
• Tx: No statement can be made about the primary tumor.

N = nodes = lymph nodes

The discovery of lymph node metastases (TNM system) depends largely on the search for them. For this reason there are guidelines for the various tumor diseases about how many lymph nodes must be examined in order to be able to rule out an infestation with a relatively high degree of certainty. In colorectal cancer, for example, at least 12 lymph nodes must be removed and examined histologically. As a rule, the number of lymph nodes removed is also given. Example: N0 (0/15). In the case of other tumor diseases, for example breast cancer, it is sufficient to take it from the sentinel lymph node (sn). This is the first lymph node in a drainage area. If this is not affected, it can be assumed with a high degree of probability that the downstream lymph nodes are also free of metastases. A detailed examination is all the more important if the sentinel lymph node is affected. This is also specified in the TNM system. Example: pN1 (sn) = histologically confirmed involvement of the sentinel lymph node.

• N0: No infection of the regional lymph nodes with tumor tissue.
• N1,2 or 3: This indicates an increasing number of affected regional lymph nodes depending on the primary tumor. A further distinction is made between lymph node metastases on the tumor side (ipsilateral) and affected lymph nodes on the opposite side (contralateral) of the primary tumor. As well as their mobility and localization in relation to the primary tumor.
• Nx: It is not possible to make any statements about the lymph node involvement.

M = metastases

This describes the presence of tumor cells that have been carried by the bloodstream to other organs and have formed further tumors there. No distinction is made between how many metastases are present or in which organ they are located. In order to specify the exact organ location, various abbreviations from the English are added at the end (TNM system) (OSS = bone, PUL = lung, HEP = liver, BRA = brain, MAR = Bone marrow, PLE = Pleura, PER = peritoneum (Peritoneum), ADR = Adrenal gland, SKI = skin, OTH = other organs)

• M0: no signs of distant metastases
• M1: Distant metastases are present
• Mx:The designation Mx (no statement about distant metastases possible) is no longer common these days. If the pathologist cannot make a statement about this, the name will be used "M" omitted (e.g. T1N0). The designation M0 is actually not histologically correct. The safe exclusion of distant metastases can only be provided by an autopsy after the patient's death, since not all tissues and organs are examined in the diagnosis. According to studies and statistics, however, there are preferred metastatic routes for the individual types of cancer. Used in these usually affected organs no metastasis discovered, the pathologist calls this M0.

C factor

With the C system describes how the tumor classification was diagnosed (TNM system).

• C1: General clinical examination and routine examinations such as classic ones X-rays.
• C2: Special examinations like Computed Tomography (CT) or ERCP.
• C3: Results of the Cytology, biopsy or other surgical diagnostics.
• C4: Results after surgery and histological examination by a pathologist. C4 is synonymous with the pTNM classification (TNM system).
  
• C5: Macroscopic and microscopic examination of all organs after the death of a patient (autopsy).

a symbol

Only became a tumor after death found during the autopsy, the TNM classification (TNM system) can be prefixed with an “a”.

y symbol

If a tumor is particularly large, it will in some cases be treated with chemotherapy or radiation before the operation.This should reduce the size and spread of the tumor and make the operation easier or even possible in the first place. In order to differentiate between the spread of the tumor before the start of treatment and before the operation, the TNM classification (TNM system) after chemotherapy "Y" added.

r symbol

Was a The tumor was initially treated successfully, but occurs again after a while, it is a Relapse. In order to be able to differentiate between the original tumor disease and the relapse, this TNM classification (TNM system) an "r" added.

Residual tumor

Of the Residual tumor indicates whether or not tumor tissue has remained in the body after an operation and removal of the primary tumor.
R0 is usually the desired end state of an operation. In the event of R1 is often resected and the cut edges are freed from the remaining tumor cells. In the event of R2 It is often about palliative operations, which are supposed to improve the quality of life of the patient, but have no prospect of a cure. In such cases the tumor disease is very advanced.

• R0: no detectable residual tumor in the tissue
• R1: microscopic detection of tumor cells at the cut edges
• R2: leave macroscopically visible tumor or metastases in the body.

Grading

• G1: Well differentiated tissue, which is still very similar to the original organ tissue.
• G2 / 3: increasingly poorly differentiated tissue.
• G4: very poorly differentiated tissue, which no longer has any similarities with the actual organ tissue.