Multimodal ultrasound for preoperative evaluation of dermatofibrosarcoma protuberans: a series of 40 cases

Abstract

Background Dermatofibrosarcoma protuberans (DFSP) is a rare, low to intermediate-grade sarcoma, which needs imaging examination. Small series of ultrasound findings in DFSP have been published; however, the usefulness of elastography and contrast-enhanced ultrasound (CEUS) in DFSP has not been studied. We aim to study multimodal ultrasound findings and report the correlation between imagings and tiny extension in DFSP for preoperative evaluation. Methods Two-D ultrasound, 3-D color ultrasound, elastography, and CEUS findings were retrospectively evaluated. Forty histopathologically confirmed DFSPs were studied. Results On 2-D ultrasound, 26(65%) appeared as mostly hypoechoic lesions with occasional hyperechoic dots within the tumor matrix and lobulated lateral borders. Eight (20%) lesions were multilayered. Ninety-five percent of lesions showed increased vascularity. On 3-D ultrasound, DFSPs showed branch-shaped, striped, and wrapped color patterns. Power Doppler showed mainly artery of a moderate arterial peak systolic blood flow and low resistance index. DFSP is hard on elastography. On CEUS, DFSPs showed a long peak time, low peak and a small amount of perfusion around the tumor, 73.7% (14/19) of lesions showed a heterogeneous contrast enhancement and 89.5% (17/19) of lesions showed hyper-enhancement. CEUS showed better concordance than US with histology on the maximum diameter and depth (P < 0.05). Conclusions Multimodal ultrasound showed significant characteristics in DFSP, which would improve diagnostic accuracy. CEUS could be an effective tool to determine tiny tumor extension.

Integrating vascularity into the pattern classification of pilomatricomas on ultrasound provides a more competent approach for discriminative evaluation

“…Posterior acoustic shadowing is predominantly present in pilomatricomas and occasionally in dermatofibrosarcomas protuberans and epidermoid cysts, while posterior acoustic enhancement is predominantly present in epidermoid cysts and occasionally in pilomatricomas. These findings are consistent with previous studies 4–8,21–23 . Vascularity is typically absent in epidermoid cysts unless there is coexisting inflammation, while it is rich in dermatofibrosarcomas protuberans and frequently present in pilomatricomas 20,22,23 .…”

“…These findings are consistent with previous studies. [4][5][6][7][8][21][22][23] Vascularity is typically absent in epidermoid cysts unless there is coexisting inflammation, while it is rich in dermatofibrosarcomas protuberans and frequently present in pilomatricomas. 20,22,23 In our study, two epidermoid cysts were mistaken as pilomatricoma and inflammatory lesions.…”

Conventional and contrast-enhanced ultrasound in the differential diagnosis of recurrent dermatofibrosarcoma protuberans and postoperative scar

“…The principle of CEUS is the introduction of contrast agent through different pathways to increase contrast within the tissues and improve the imaging of tissues, organs, and lesions [ 27 ]. Furthermore, the use of preoperative CEUS to improve the precision of DFSP resection was reported by Ma and in our previous study [ 14 , 15 ]. The results of our study suggest that CEUS can provide valuable information distinguishing recurrent DFSP from post-resection scars; 30% of postoperative scars showed no entry of contrast agent, and recurrent DFSP was more likely to show heterogeneous and hyper-enhancement relative to normal peripheral soft tissue, which was possibly associated with the presence of necrosis or mucus components, and some vascularization, respectively, in the tumor.…”

“…There have been several reports on the US features of DFSP [ 7 – 13 ]. In addition, two reports [ 14 , 15 ] found that CEUS provided a new method for locating and predicting the size of DFSP tumors, and CEUS displayed higher concordance than US with histology regarding maximum diameter and depth [ 15 ].…”

Diagnostic accuracy of high-frequency ultrasound for cutaneous neoplasms: a narrative review of the literature

“…More recently, several studies have described DFSP as oval hypoechoic dermal and follicular induction indicated by hyperechoic epidermal areas with tentacle-like projections into the subcutaneous fat [ 115 , 116 ]. Hypoechoic areas with a storiform growth pattern on histology correlated with hyperechoic areas with a histologic honeycomb invasive pattern [ 114 , 115 , 117 , 118 ]. Of note, one case study reported a DFSP originally mistaken on ultrasound for a lipoma; [ 119 ] thus, high clinical suspicion should still be used in cases where DFSP is on the differential.…”