Cumulative Sum Analysis for Learning Curve for Breast Mass Excision Using an Ultrasound-Guided Vacuum-Assisted Biopsy System

Abstract

Purpose: The aim of the study was to evaluate the existence of a learning curve for procedures using ultrasound-guided vacuum-assisted breast biopsy (VAB) system in terms of the cumulative sum (CUSUM). Methods: Data from a series of 54 consecutive patients who had undergone ultrasound-guided VAB were reviewed in the study. Patients’ characteristics, operative times, and complication rates were analyzed. The total operation time was analyzed by using the CUSUM method. Results: CUSUM analysis revealed three phases of the learning curve: phase 1 (the initial 15 cases), phase 2 (intermediate 23 cases), and phase 3 (subsequent cases). Operative times, including preparation time, procedure time, and total operation time, in phase 1 were significantly longer than those in phases 2 and 3. Surgical complications were the most frequent in the initial phase (26.7%); however, complication rates were not significantly different among the three groups. Conclusion: The current study showed the three different phases of the learning curve for ultrasound-guided VAB using CUSUM analysis. CUSUM analysis can be used to determine appropriate competency of various procedures in patients with breast diseases.