TNMF versus TNM in staging of colorectal cancer

• TNM staging of colorectal cancer has undergone minimal changes during the past 20 years despite their impact on the prognosis.
• In this Paper we drew the attention to several risk factors of colorectal cancer that are not included in the TNM system.
• We suggest the addition of ‘F’ to the TNM system to include the continuous expanding list of risk factors of colorectal cancer.

AimTNM staging and histological grading of rectal cancer has undergone no or minimal changes during the past 20 years despite their major impact on planning, reporting and outcome of the disease. The addition of category ‘F’ to the ‘TNM’ staging of colorectal cancer, which becomes TNMF will accommodate the expanding list of risk factors that may affect the management and thus avoid squeezing them into the TNM categories.MethodsReporting of the following risk factors was traced in 730 (664 retrospective and 66 prospective) cases of colorectal cancer: age, Tumor location, preoperative CEA, intraoperative tumor perforation and blood transfusion, quality of TME, tumor grade, non nodal T.Ds, Lymphovascular invasion, lymph node ratio, circumferential tumor margins, apical lymph nodes, infiltrating or pushing and K-ras gene mutation.ResultsThe reporting of most risk factors was inadequate; also there is marked improvement in reporting in the prospective cases in preoperative CEA, intra operative blood transfusion and tumor perforation, quality of TME, tumor grade and non-nodal T.Ds (P-value <0.0001).ConclusionThe addition of category ‘F’ to the TNM staging system to become TNMF may avoid ignoring already established risk factors due to our inability to accommodate them in the inhospitable TNM categories.