Abstract
Background Tumor grade is one of the more controversial factors, and the data regarding its prognostic impact in squamous cell carcinoma (SCC) of the uterine cervix are controversial. Methods The histological slides of 467 surgically treated FIGO stage IB1 to IIB cervical SCC were re-examined regarding the prognostic impact of the histological tumor grade based on the degree of keratinization (conventional tumor grade) according to the WHO recommendation on recurrence-free and overall survival as well as on the prediction of pelvic lymph node involvement. Results 46.0% presented with well-differentiated tumors (G1, n = 215), 30.6% with moderate (G2, n = 143) and 23.3% with poor differentiation (G3, n = 109). The recurrence-free survival was significantly reduced in patients with poorly differentiated tumors (G1: 81.4%, G2: 70.6%, G3: 64.2%; p = 0.008). There was no impact on overall survival. Because of the lack of survival differences between G1- and G2-tumors, they were merged into low-grade tumors, and their prognostic outcome was compared to the high-grade group (G3-tumors). Based on this binary conventional grading system there was a significantly longer recurrence-free (low-grade: 77.1% vs. high-grade: 64.2%; p = 0.008) and overall survival (low-grade: 76.0% vs. high-grade: 65.1%; p = 0.031) in the low-grade group. However, both the conventional three-tiered and the binary grading systems (separating tumors into a low- and high-grade group) failed to predict pelvic lymph node involvement (p = 0.9 and 0.76, respectively). Conclusion A binary grading model for the conventional tumor grade (based on the degree of keratinization) in SCC of the uterine cervix may be suitable for the prognostic survival evaluation but failed to predict pelvic lymph node involvement.