© 2007 Foundation for Promotion of Cancer Research
Which is the Better Pathological Prognostic Factor, the Nottingham Histological Grade or the Japanese Nuclear Grade? A Large Scale Study with a Long-term Follow-up
1 Departments of Pathology
2 Breast Surgery, Seirei Hamamatsu General Hospital, Hamamatsu, Shizuoka
3 Kanzaki Clinic, Hamamatsu, Shizuoka, Japan
For reprints and all correspondence: Hiroshi Kobayashi, Department of Pathology, Seirei Hamamatsu General Hospital, 2-12-12 Sumiyoshi, Hamamatsu, 430-8558, Japan. E-mail: kobayashi{at}sis.seirei.or.jp
Received October 3, 2006; accepted November 13, 2006
Background: We compared the Nottingham histological grade (H-grade) and the Japanese nuclear grade (N-grade) to select the better prognostic factor for breast cancers.
Methods: The series included 1786 patients with breast cancers with the exception of non-invasive and stage 4 cancers. They were classified according to the H- and N-grade. We analyzed their survival curves and also performed multivariate Cox regression analyses.
Results: According to the H-grade classification, 476 cases were grade 1, 647 cases were grade 2 and 663 cases were grade 3. According to the N-grade, 381 cases were grade 1, 215 cases were grade 2, and 1129 cases were grade 3. In the survival curves of those cases with lymph node metastases (N(+)) and recurrent cases, there were statistically significant differences in different categories of the H-grades, but not in the N-grades. The survival curves of all the cases and those cases without lymph node metastases (N(–)) always exhibited statistically significant differences. According to the 2003 St Gallen consensus, the N(–) group was classified as a minimal risk and an average risk groups. Both H- and N-grade exhibited statistically significant differences between the minimal risk and the average risk groups in the disease-free survival. The multivariate analyses proved that the H-grade was a statistically significant prognostic factor in all the cases and N(+) group, but the N-grade was not significant in any of the studies.
Conclusions: The H-grade is clearly proved to be a more significant prognostic factor for wider stage cases than the N-grade.
Key Words: breast cancer • histological grade • pathological grade • prognostic factor