Tumor Budding Grade and T Stage as Recurrence Predictors of High-risk Stage II Colorectal Cancer.

BACKGROUND/AIM: High-risk features for recurrence in patients with pathological stage II colorectal cancer (pStage II-CRC) remain controversial. T4 stage (T4) is a strong prognostic factor. The SACURA trial showed that the high tumor budding group (BD3) had a significantly lower 5-year relapse-free survival (RFS) than the low and middle budding groups, although the BD3 group had a higher proportion of patients with T4. This study aimed to investigate the association between T4 and BD3 as a prognostic factor for pStage II-CRC.

PATIENTS AND

METHODS

We retrospectively examined 448 consecutive patients with pStage II-CRC at our institution between January 2013 and March 2019. First, we identified prognostic factors affecting RFS among high-risk features, including: <12 lymph nodes examined, lymphatic, vascular, or perineural invasion, T4, BD3, and poorly differentiated/mucinous histology. Next, we compared 5-year RFS among three groups: patients with only BD3 (Group A), patients with only T4 (Group B), and patients with both T4 and BD3 (Group C).

RESULTS

The characteristics of the 448 patients were as follows: T4, 10%; BD3, 52%; <12 lymph nodes, 15%; poorly differentiated or mucinous adenocarcinoma, 6%; lymph/vascular/perineural invasion, 78/70/22%. The median follow-up duration was 63 months. Multivariate analysis identified T4 and BD3 as independent prognostic factors affecting RFS. The 5-year RFS in group C (23 patients: 55.3%) was significantly lower than those of groups A (215 patients: 84.0%) and B (20 patients: 73.7%) [A vs. C: hazard ratio (HR)=3.85, 95% confidence interval (CI)=1.95-7.62; B vs. C: HR=2.34, 95%CI=0.85-6.42, p=0.002].

CONCLUSION

Patients with high-risk pStage II-CRC who have T4 and BD3 factors have poor RFS.