TNM Classification

The letters T-N-M are abbreviations and stand for:

T = tumour, in the sense of primary tumour;

N = Nodus lymphaticus (lymph node), in the sense of regional lymph node metastases;

M = metastasis, in the sense of haematogenic distant metastases; T = primary tumor

Tis or Cis: tumour in situ, carcinoma in situ; T1, T2, T3, T4: indicates the size of the primary tumour (T1=small, T4=large)

N = Regional lymph node metastases N0: no indication for lymph node metastases N1, N2, N3, N4: indicates the extent of regional lymph node metastasis

M = distant metastases M0: no indication for distant metastases M1: distant metastases detected

If the primary TNM formula must be changed due to later findings (surgical treatment, histological examination), this is indicated by special additives. A prefixed ″p″ means, for example, that the stadium division was carried out taking into account a pathohistological OP finding (pTNM former).

Other tumor characteristics:

Typing (cell type): histological classification of a tumor according to its original tissue. Example: adenocarcinoma. Squamous cell carcinoma, leiomyosarcoma; important for further treatment because the individual cell types respond very differently to radiation treatment or chemotherapy.

Grading (cell differentiation): The term means the degree of histological malignancy.

G1 means high differentiation (good prognosis, because highly differentiated tumors with a low degree of malignancy (in practice: bronchial carcinoids, rarely also squamous epithelial or azinic (berry-shaped) adenocarcinomas))

G2 mean differentiation, mean highly differentiated tumors with mean malignancy (in practice: mostly bronchial wall gland carcinomas, rarely also squamous epithelial or papillary adenocarcinomas)

G3 weitgehende Entdifferenzierung (schlechte Prognose, weil wenig differenzierte Tumoren mit hohem Malignitätsgrad (in praxi: abhängig vom Staging) alle fortgeschrittenen nichtkleinzelligen Lungenkarzinome).

G4 undifferenzierte Tumoren mit sehr hohem Malignitätsgrad (in praxi: abhängig vom Staging alle kleinzelligen Lungenkarzinome).

R-Klassifikation: Für die Prognose nach einer Op. ist entscheidend, ob Tumorreste im Körper verblieben sind.

R0-Resektion: kein Resttumor

R1-Resektion: mikroskopischer Tumorrest

R2-Resektion: makroskopischer Tumorrest, infiltrationstiefe histologisch nachweisbare Tiefenausdehnung. Die Frage ist nun, ob bei nachgewiesenen Gefäßeinbrüchen der Primärtumor bereits Metastasen auf dem Lymph- oder Blutweg gesetzt hat (wahrscheinlich).