Diagnosis and differential diagnosis of dermatofibrosarcoma protuberans: Utility of high-resolution dynamic contrast-enhanced (DCE) MRI.

BACKGROUND: Dermatofibrosarcoma protuberans (DFSP) is a kind of low-grade malignant spindle cell neoplasm, the diagnosis, and treatment, which have markedly attracted clinicians' attention for its repeated recurrence. High-resolution magnetic resonance imaging (HR-MRI) has shown unique capabilities in diagnosis of various cutaneous tumors. MATERIALS AND METHODS: Data of 29 patients with clinically suspected DFSPs and undergoing dynamic contrast-enhanced (DCE) HR-MRI preoperatively were prospectively collected. The HR-MRI qualitative features were evaluated and compared. The DCE-associated quantitative parameters and the time-signal intensity curve (TIC) types were provided using DCE sequences. RESULTS: A total of 7 DFSPs, nine dermatofibromas (DF, including four cases of cellular variant [CDF]), 12 keloids, and one nodular fasciitis were enrolled. DFSP showed the largest major diameter and the deepest depth. Five DFSPs (71.4%) showed ill-defined margins as well as infiltration of peripheral adipose. All DFSPs showed irregular shape. Most DFSPs presented hyperintensity on T2 WI (71.4%) and iso-intensity on T1 WI (85.7%). Six cases (85.7%) had significant enhancement, and six cases (85.7%) had homogeneous enhancement. There were significant differences of Ktrans , Kep , Ve and iAUC values among DFSPs, DFs, and keloids, and DFSP had the highest values for these parameters. Six DFSPs (85.7%) and four CDFs (100%) showed type-III TICs, while the other lesions showed type-Ⅰor type-Ⅱ TICs. CONCLUSIONS: DCE-HR-MRI could show the growth characteristics of DFSPs, which was of great value for the diagnosis and differential diagnosis of DFSPs and was helpful for the determination of treatment options, thereby to improve the prognosis of patients.

The value of preoperative high-resolution MRI with microscopy coil for facial nonmelanoma skin cancers.

BACKGROUND: The extent and depth of facial nonmelanoma skin cancers and the involvement of adjacent structures are critical features for surgical planning, but they are difficult to assess clinically. High-resolution MRI (HR-MRI) with microscopy coil may facilitate detailed evaluation of skin lesions. The authors performed this prospective study to determine the value of high-resolution microscopy coil MRI in the preoperative evaluation of nonmelanoma skin cancer. MATERIALS AND METHODS: Between October 2018 and August 2019, 16 lesions from fifteen consecutive patients with facial nonmelanoma skin cancer were evaluated using high-resolution microscopy coil MRI about tumor extent, depth, margins, characteristic, and their spatial relationship with adjacent structures. The preoperative HR-MRI results were compared with the intraoperative findings and with the histopathology, with special note to the depth of invasion. RESULTS: Among the 16 lesions, HR-MRI imaging was found to provide accurate evaluation of tumor extent, depth, and margins and determine whether there was involvement of adjacent structures. The tumor depth measured on HR-MRI showed good correlation with histopathologic results (CCC: 0.973), and Bland-Altman analysis finding no significant bias existed between the two measurements. All lesions except one were completely resected with primary excision. Only one lesion required further excision. During follow-up for 3-15 months, no tumor recurrence was observed in any case. CONCLUSIONS: HR-MRI is an accurate, noninvasive imaging technique that can be used as preoperative evaluation tool for facial nonmelanoma skin cancer. It can accurate predict tumor depth, margins, and involvement of structure. The valuable information it provided facilitates surgeons optimize surgical planning.

Clinical value of high-resolution dynamic contrast-enhanced (DCE) MRI in diagnosis of cutaneous squamous cell carcinoma.

BACKGROUND: While uncomplicated cases of skin squamous cell carcinoma (cSCC) can be treated with surgery topical therapy alone, more objective and non-invasive examination methods are needed to guide clinicians to make more detailed biopsy and surgical plans for lesions with atypical or subcutaneous growth. High-resolution magnetic resonance imaging (HR-MRI) is a novel skin imaging method. MATERIALS AND METHODS: Prospective collection of 19 patients with clinically suspected cSCC. All patients underwent high-resolution DCE-MRI using a 70-mm microscopy coil before operation. The imaging features and results of surgical pathology were recorded. Ktrans , Kep , Ve values, and the time-signal curve (TIC) types were determined using DCE images. RESULTS: 16 cases of cSCC, 3 cases of acanthoma. The subcutaneous invasion of all lesions was clearly displayed, of which 8 lesions invaded the subcutaneous fat layer, 5 invaded the muscle layer, 1 invaded the periosteum, 2 invaded the cap fascia, and the layer of all lesions invasion judged by HR-MR imaging was consistent with the postoperative pathology. The main manifestations of cSCC were ill-defined margin, obvious inhomogeneous enhancement, higher perfusion parameters value and type-III TIC, while acanthoma showed well-defined and type-I TIC. Some imaging findings (such as boundary, enhancement) and DCE perfusion parameters of the two groups overlap. CONCLUSION: High-resolution DCE-MRI can fully and directly display the subcutaneous invasion of cSCC, and more work needs to be done to prove its value. Next, we will expand the sample size, and further explore its value in the differential diagnosis and prognosis evaluation of cSCC from acanthoma or other skin tumors.