Decrease in Calcifications After Neoadjuvant Treatment Predicts Invasive Tumor Response but Not Complete DCIS Eradication: Systematic Review and Meta-Analysis

Changes in calcifications after neoadjuvant treatment and their relationship with pathological complete response in breast cancer remain unclear. We conducted a systematic review and meta-analysis to evaluate this association. A PubMed and EMBASE search was conducted for English-language studies assessing changes in calcification size or number before and after neoadjuvant treatment and their correlation with post-treatment histology. Pooled odds ratios and 95% confidence intervals were calculated using a random-effects model. Study heterogeneity, publication bias, and quality were assessed using the Cochrane Q test, I² statistic, funnel plot, and Slim's method. Of 2261 records screened, 8 studies comprising 707 patients were eligible. Decreased calcifications after neoadjuvant treatment were associated with higher odds of achieving pathologic complete response (pooled odds ratio of 1.691, p < 0.001). Subgroup analyses showed significance for decrease vs. no-decrease (odds ratio = 2.045; p = 0.004), a trend for decrease vs. increase, and no significance for no-increase vs. increase. Stratification by pathologic complete response definition demonstrated significance when residual DCIS was permitted (odds ratio of 2.196; p < 0.001) but not when complete absence of DCIS was required. Patients with a decrease in calcifications after neoadjuvant treatment are twice as likely to achieve pathologic complete response, particularly when residual DCIS is permitted within the pathologic complete response definition. Calcification changes may serve as an additional tool for guiding surgical planning after neoadjuvant treatment.