Improvement of staging by combining tumor and treatment parameters: the value for prognostication in rectal cancer.
OBJECTIVE
Staging of cancer is based on the TNM system. This valuable system takes only tumor-related parameters into account, but in the era of refined surgery and preoperative therapy treatment-related factors are of equal importance. By using rectal cancer as a model we explored the hypothesis that a combination of tumor- and treatment-related parameters will result in improved prognostication.


METHODS
Standardized clinicopathologic and histologic factors considered predictive for survival were studied in eligible patients treated in a trial for rectal cancer (n = 1324). These factors were analyzed in relation to survival using log-rank tests, Kaplan-Meier curves, and Cox regression both individually and in combination, the latter including TNM staging. A second data set from an independent trial (n = 316) was used for data validation.


RESULTS
Multivariate analysis identified nodal status (P = .001) and circumferential margin (P = .001) involvement as the most important prognostic factors for survival. The combination of these factors formed an improved staging system (node status and circumferential margin [NCRM]) compared with the present TNM staging with respect to 5-year cancer-specific survival. The results were confirmed in our independent patient population.


CONCLUSIONS
NCRM staging of rectal cancer results in a broad range of survival rates and favorable patient grouping. Our data give strong evidence that a staging system combing tumor- and treatment-related factors provides better prognostic information than the classic TNM system, which is based solely on tumor-related factors. Similar results might be obtained in other types of cancer in which quality of treatment is important for outcome.
Gosens
Marleen J E M
MJ
Department of Pathology, Radboud University Medical Center, Nijmegen, The Netherlands.
van Krieken
J Han J M
JH
Marijnen
Corrie A M
CA
Meershoek-Klein Kranenbarg
Elma
E
Putter
Hein
H
Rutten
Harm J
HJ
Bujko
Krzysztof
K
van de Velde
Cornelis J H
CJ
Nagtegaal
Iris D
ID
D003082:Colectomy / Q000379:methods*; D003113:Colonoscopy; D003718:Denmark / Q000453:epidemiology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009367:Neoplasm Staging / Q000379:methods*; D011379:Prognosis; D018714:Radiotherapy, Adjuvant; D012004:Rectal Neoplasms / Q000401:mortality / Q000473:pathology* / Q000628:therapy; D012720:Severity of Illness Index; D015996:Survival Rate