A STUDY OF CLINICOPATHOLOGICAL SIGNIFICANCE OF TUMOUR BUDDING IN BREAST CARCINOMA

Abstract

Introduction: Tumour budding (TB) is a new prognostic marker whose role in breast cancer is still under evaluation. Our aim was to study TB in breast carcinoma and correlate it with other prognostic markers.

Methods: A descriptive cross-sectional study was conducted over 2 years on 75 invasive breast carcinoma specimens and biopsies. Hematoxylin and Eosin sections were examined for tumour grade, stage, molecular subtype, necrosis, lymphovascular invasion (LVI), inflammation and counting TB. Lymph node (LN) metastasis was studied only in mastectomies. TB was defined as cluster of 1-5 tumour cells and counted in 10 consecutive 400X fields. The cut-off for high grade TB was taken as ≥10 per 10 HPFs. Immunohistochemical staining was done for molecular subtyping and differentiating TB from mimickers. Statistical analysis was done using chi square test and Fischer’s exact test.

Results: TB was present in 66/75 cases; 53% (n=35) were high grade. Among these, majority were of T2 (74%, n= 26), grade 2 (52%, n= 18), luminal A (34%, n= 12), had 3+ inflammation (46%, n= 16) and peripheral tumour buds (54%). Necrosis and lymphovascular invasion were absent in 77% and 71%, respectively. LN metastasis was seen in 63% (n= 25/28) cases. Statistically significant association (p= 0.016) was observed between degree of inflammation and TB grade. However, no significant association was observed between TB and other prognostic markers.

Conclusions: In our study, association of TB with different prognostic markers was appreciated but was not statistically significant. However, it highlights need for standardization of TB reporting.