# Evaluation of histomorphological changes in breast cancer following neoadjuvant therapy at a tertiary care centre, Jharkhand

## TL;DR

This study shows that neoadjuvant therapy significantly changes breast cancer tissue, helping predict treatment response and outcomes.

## Contribution

The study provides empirical evidence of histomorphological changes in breast cancer after neoadjuvant therapy in a specific regional population.

## Key findings

- Neoadjuvant therapy significantly reduced tumor cellularity and increased fibrosis in breast cancer patients.
- Pathological complete response rates were highest in triple-negative and HER2-positive breast cancer subtypes.
- High post-treatment tumor-infiltrating lymphocytes strongly correlated with better treatment response.

## Abstract

Breast cancer remains a major cause of cancer-related mortality among women worldwide, with treatment response prediction posing a
persistent challenge. Neoadjuvant therapy (NAT) offers tumor downstaging and assessment of histopathological response. In this
prospective study of 125 patients, NAT led to a significant reduction in tumor cellularity (82.4% ± 12.3% to 31.7% ±
18.9%, p < 0.001) and increased fibrosis (15.2% ± 8.7% to 48.6% ± 15.4%, p < 0.001). Pathological complete response
(pCR) occurred in 32% of patients, with higher rates in triple-negative (42.1%) and HER2-positive (38.5%) subtypes. High post-NAT
tumor-infiltrating lymphocytes correlated strongly with pCR (r = 0.67, p < 0.001). Thus, we show that NAT induces significant
histomorphological changes, which can serve as key prognostic indicators for therapeutic response and patient outcomes.