“Wagashi Sign” : Sonographic Signs to Categorize Breast Tumorous Lesions

Abstract

Objective : Specific imaging findings in sonography are known as “signs.” For example, the target sign is characteristic of intussusception. The bull's eye sign is the signature of metastatic liver cancer. This study aims to assess if “Wagashi signs”, a sonographic sign named after traditional Japanese confections may be useful for categorizing breast tumorous lesions for ultrasound trainees.

Methods : Ultrasound features of breast tumorous lesions were classified into three categories, and each category was denoted as a different type of Wagashi : a Daifuku mochi (small round cake) sign indicates category 3, Sataandagi (irregularly shaped fried bun) sign indicates category 4, and Konpeito (sugar candy covered in small nodules) sign indicates category 5. We taught this method to ultrasound trainees (7 ultrasound technicians, 3 doctors) for ten minutes and tested them for the accuracy and the timeliness with which they were able to classify breast tumorous lesions.

Results : The tests revealed that the participants accurately classified the lesions, and they did so quicker than when using the conventional flow chart to categorize tumorous lesions.

Conclusions : “Wagashi signs” are useful in assisting ultrasound trainees for categorizing breast tumorous lesions.