Ultrasound Biomicroscopy and High‐Frequency Ultrasound for Evaluating Extramammary Paget Disease With Pathologic Correlation.

Objectives: The purpose of this study was to investigate the performance of ultrasound biomicroscopy (UBM) and high‐frequency ultrasound (HFUS) in the assessment of extramammary Paget disease (EMPD) and to correlate the imaging features with pathologic findings. Methods: In this retrospective study, we described the imaging features from UBM and HFUS based on 17 pathologically proven EMPD cases. The performance for visualizing layer involvement by UBM and HFUS was compared. Additionally, we checked the consistency between layer involvement of the lesions on UBM images and the pathologic results. Additionally, blood flow and the status of lymph nodes were investigated with HFUS. Results: Ultrasound biomicroscopy revealed that all 17 lesions (100%) were hypoechoic and grew in a creeping form. The feature of layer involvement was shown in 10 lesions (58.8%) limited to the epidermis and 6 lesions (35.3%) involving the dermis, and the remaining lesion (5.9%) involved the full skin layers. Layer involvement was clearly displayed by UBM for all lesions (100%) but for only 5 lesions (29.4%) by HFUS (P < .001). Additionally, the layer involvement of 15 lesions (88.2%) on UBM was consistent with the pathologic results (κ = 0.746). High‐frequency ultrasound revealed profuse blood flow in most lesions (64.7% [11 of 17]), and 1 case showed inguinal lymph node metastasis. Conclusions: Combined use of UBM and HFUS can provide key information on EMPD based on ultrasound features. Comparatively, UBM provides clearer morphologic information, whereas HFUS provides information on lymph node metastasis and blood flow. [ABSTRACT FROM AUTHOR]