Background: Numerous grading systems have been proposed for invasive ovarian epithelial carcinoma. But, conflicting reports have been published addressing the value of grade as an independent prognostic factor.
Design: The present study investigated the consistency, reproducibility and prognostic value of four different grading systems in a series of 100 homogeneously treated (cytoreductive surgery & platinum based chemotherapy) patient. All the slides were reviewed in a double-blind manner by 3 pathologists, typed according to the WHO and graded. Multivariate assessment of survival time was performed with the Cox model.
Results: Population parameters - mean age: 60 years, - stage (FIGO) III & IV 85% - survival: 5 years OS: stage III & IV=22,5%. No significant difference for survival was observed when the patients were classified with any of the 4 grades evaluated. Prognostic factors: age<60 (p<0,001), optimal surgery (p<0,01), n+(p<0,02), necrosis>50% (p<0,04), mitotic count<15MF/10HPF (p<0,03) and vascular invasion (p<0,03). Those 3 parameters were assigned to a new highly relevant grade. At multivariate analysis, it was significantly associated with DFS and OS (p<0,01).
Conclusion: Our grade is simple, useful for all histologic types, non subjective and reproducible. Further studies are warranted to confirm its clinical utility.