Preoperatively determining the margins of subcutaneous malignant soft tissue tumours using contrast-enhanced ultrasonography.

The purpose of this technical report is to demonstrate the feasibility of contrast-enhanced ultrasonography for preoperative evaluation of the lateral extent of subcutaneous malignant soft tissue tumours. Patients with subcutaneous malignant soft tissue tumours who underwent surgery between March 2016 and May 2016 were selected for inclusion. Contrast-enhanced ultrasonography using Sonazoid® was performed 1 day before the operation. The tumour margin was determined based on contrast-enhanced ultrasonography and marked on the skin using a permanent marker. After surgery, the extent of the tumour area was determined based on microscopic findings. The distance between the edge of the tumour and the skin markings was histologically measured. The mean distance between the extent of infiltrative tumour growth based on the microscopic findings and the skin marking was 1.3 ± 1.6 mm. The greatest distance between microscopically determined tumour invasion and the skin marking was 4 mm. Contrast-enhanced ultrasonography of subcutaneous malignant soft tissue tumours was not only feasible, but also highly accurate in estimating tumour margins as well as infiltrative tumour growth compared with macroscopic and microscopic analysis, respectively.