TNM classification


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TNM classification

Oncology An international system for staging malignancy which measures 3 major parameters of a cancer: T–size or extent of the primary tumor, as determined by clinical exam, endoscopy, laparoscopy, biopsy or resective procedures, categorized as being 1-4 and a-d depending upon site, size, and spread; N–number of involved lymph nodes, categorized as X–unknown status, 0–none identified, 1–one to several, 2–a whole bunch of positive LNs; M-X, unknown presence or absence of metastases. See Staging.
TNM classification for staging malignancy
T Tumor
Tis    Carcinoma in situ
Ta  Non-invasive
Tx   Cannot be evaluated for nonspecified reasons
T0  Localized tumor
T1  Lesion extends to muscle–bladder, colon, breast
      T1a < 0.5 cm in greatest dimension
  T1b < 1.0 cm in greatest dimension
  T1c < 2.0 cm in greatest dimension
T2  Invasion into muscle
T3  Persistent induration of organ after resection
   T3a Invasion to deep muscle
   T3b Invasion through the organ
T4  Tumor invasion or fixation
   T4a Adjacent organ invasion
   T4b Fixation to bladder or colonic wall; in breast, edema
N Nodes
N0  No lymph node metastasis
N1  One regional lymph node metastasis
N2  Multiple, mobile regional lymph node metastases
N3  Fixed regional lymph node metastases
N4  Beyond regional lymph node involvement
NX  Lymph nodes, not evaluable
M Metastasis
M0 No evidence of metastases
M1  Distant metastases are present
MX Distant metastases not evaluable  

TNM classification

A method of classifying malignant tumors with respect to primary tumor, involvement of regional lymph nodes, and presence or absence of metastases.
See also: classification
References in periodicals archive ?
In contrast to TNM classifications of other organs, the T stage for TET did not consider size of the tumor because it was thought that the malignant potential of thymoma was due to its invasiveness and its tendency to disseminate rather than its size.
The expression pattern of CD55 did not correlate with age or sex of the patients but was associated with the grade of tumor differentiation and the TNM classification of the colon cancers (Figures 3 and 4; Table 2).
Central nervous system tumors are difficult to report with a universal synoptic report designed for another organ system for which the TNM classification system is used.
They present recent proposals for a TNM classification, as well as guidelines for the management of patients with appendiceal endocrine tumors.
As the structure of TNM classification of CRC is basically quantitative (pT1 to pT4 according to the involved layers of the intestinal wall and pN1 or pN2 according to the number of metastatic lymph nodes), the insertion of qualitative features related to either the pT or pN category could alter the inherent essence of this classification approach.
(12,13,22) Interestingly, the TNM classification proposed by the European Neuroendocrine Tumor Society for AET allows distinguishing minimal ([less than or equal to] 3 mm) from deep mesoappendiceal invasion.
The TNM classification does not discriminate between multiple independent primary tumors, tumor satellite nodules, or intrahepatic metastasis from a single primary carcinoma.
The IASLC lung cancer staging project: proposals for the revisions of the T descriptors in the forthcoming eighth edition of the TNM classification for lung cancer.
(40-44) There is insufficient evidence from which to derive robust guidance on the management of these malignancies and neither UICC nor AJCC provide a separate TNM classification. The authors suggest, pragmatically, that pathologists encountering primary tracheal malignancies should report them by using the data set for hypopharyngeal carcinomas.
The neoplasia was completely staged as squamous cell carcinoma of the lung, stage IV cT2b-N2M1b (mediastinal and left hilar lymph nodes and liver metastases) according to the 7th edition of TNM classification (1).
However TNM classification does not provide enough information about treatment response, prognosis, or biological aggressiveness of HNC.