Z Gastroenterol 2015; 53 - P35
DOI: 10.1055/s-0035-1551723

Grading lymph node metastasis – a feasible approach for prognostication of stage III colorectal cancer patients

A Resch 1, L Harbaum 2, MJ Pollheimer 1, P Kornprat 3, RA Lindtner 4, C Langner 1
  • 1Institute of Pathology, Medical University of Graz, Graz, Austria
  • 2Department of Oncology, Haematology, BMT with Section Pneumology, University Medical Center Hamburg-Eppendorf/, Hamburg, Germany
  • 3Department of Surgery, Medical University of Graz, Graz, Austria
  • 4Department of Surgery, Medical University of Innsbruck, Innsbruck, Austria

Background:

The identification of parameters, which are associated with disease progression or, on the contrary, favorable outcome is an important aspect of current cancer research, since these parameters might influence patient management, in particular guide therapeutic decisions. This study aimed to assess the clinicopathological significance of tumor differentiation of metastatic lymph node tissue in AJCC/UICC stage III colorectal cancer patients.

Material and Methods:

The study cohort comprised 145 patients, 92 males (63%) and 53 females (37%) (ratio: 1.7: 1) with a mean age of 68.8 (median 68.4, range 40.4 – 92.3) years. All slides were retrospectively evaluated by two independent investigators who were blinded to clinical data. Grading was performed separately for primary tumors and corresponding lymph node metastases, according to WHO guidelines, assessing the extent of glandular appearance.

Results:

Lymph node grades were G1 in 77 (53.1%), G2 in 41 (28.3%), and G3 in 27 (18.6%) cases, respectively. Despite differences in 77 (53.1%) cases, primary tumor and lymph node grade were largely concordant (Somer's D = 0.639; p < 0.001). Lymph node grade was significantly associated with N classification (p = 0.009), tumor size (p = 0.024), and lymphovascular invasion (p = 0.004). Patients with lymph node grade G1 had better progression-free survival (p = 0.031) and cancer-specific survival (p = 0.008). Cox's multivariable regression analysis proved lymph node grade to be superior to primary tumor grade in predicting outcome of affected patients and identified lymph node grade as predictor of cancer-specific survival (but not of progression-free survival),

independent of T classification, lymphovascular invasion, as well as patient age and gender.

Conclusion:

Survival analysis proved lymph node grade to be a significant novel prognostic parameter for patients with AJCC/UICC stage III disease, which appeared superior to primary tumor grade. Additional studies are warranted to validate this new finding.