Strain wave elastography in response assessment to neo-adjuvant chemotherapy in patients with locally advanced breast cancer

Abstract

Objective: The study was conducted to study the role of strain wave elastography in evaluating the response to neo-adjuvant chemotherapy (NACT) in patients with locally advanced breast cancer (LABC). Methods: In this Institutional review board approved study, 86 patients of LABC were investigated with strain wave elastography. Females receiving NACT had the affected breast scanned by strain wave elastography before each cycle of chemotherapy and immediately before surgery by two independent observers. Changes in elastographic parameters (size ratio, strain ratio) were documented and then compared to clinical and pathologic tumor response as evaluated after mastectomy. Results: Elastographic strain ratio parameters demonstrated high sensitivity and moderate specificity for determining response even after the first cycle of neo-adjuvant chemotherapy [97.7% sensitivity (Sn), 68.7% specificity (Sp)]. Elastographic size ratio parameters showed moderate sensitivity and specificity for response detection after second and third cycle of neo-adjuvant chemotherapy (Sn, Sp: After second cycle of NACT Sn 83.3% Sp 80%; after third cycle of NACT Sn 77.8% Sp 100%). Conclusion: Strain ratio is the earliest predictor of treatment response in patients of LABC. Serial imaging with elastography has the potential to predict treatment response early during the course of NACT, which may prove vital in management of patients with breast cancer. Advances in knowledge: Strain wave elastography is a powerful tool to predict chemoresponse early during the course of management, thereby providing an optimal window to change treatment protocols.