Color Doppler Sonography of Extradigital Glomus Tumors

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

High-frequency ultrasound has been used to visualize depth and vascularization of cutaneous neoplasms, but little has been synthesized as a review for a robust level of evidence about the diagnostic accuracy of high-frequency ultrasound in dermatology. A narrative review of the PubMed database was performed to establish the correlation between ultrasound findings and histopathologic/dermoscopic findings for cutaneous neoplasms. Articles were divided into the following four categories: melanocytic, keratinocytic/epidermal, appendageal, and soft tissue/neural neoplasms. Review of the literature revealed that ultrasound findings and histopathology findings were strongly correlated regarding the depth of a cutaneous neoplasm. Morphological characteristics were correlated primarily in soft tissue/neural neoplasms. Overall, there is a paucity of literature on the correlation between high-frequency ultrasound and histopathology of cutaneous neoplasms. Further studies are needed to investigate this correlation in various dermatologic conditions.

High-frequency ultrasonography for subungual glomus tumor evaluation - imaging findings

OBJECTIVE

This article aimed to describe the common imaging features of subungual glomus tumors.

METHODS

The study involved data collected between January 2019 and December 2022. Twenty-three patients with a total of 31 glomus tumors underwent high-frequency ultrasound examinations with a 24-MHz probe. Two experienced radiologists independently evaluated the images, and only data from the more experienced radiologist were used for subsequent analyses.

RESULTS

The average size of the tumors was 4.6 mm, and most of them appeared homogeneously hypoechogenic (90.3%). Bone remodeling of the distal phalanx was observed in 87.1% of cases, with an average axial circumference loss of 0.8 mm, indicating the slow and expansive growth of glomus tumors. Intense vascularization was found in 54.8% of cases on Doppler images, and the stalk sign, reflecting the vascular origin of the tumor, was present in 64.5% of cases. The most common clinical feature was pain, reported in 84.6% of cases, with a mean pain scale score of 7.0, indicating a negative impact on patients' lives despite being benign tumors.

CONCLUSION

The study concludes that ultrasound evaluation is highly useful for diagnosing glomus tumors, especially when multiple findings, such as bone remodeling, hypervascularization, and the stalk sign, are present. This method allows for accurate diagnosis, observation of periungual structures, and proper surgical planning, ultimately reducing recurrence rates.

Practical approach to ultrasound of soft tissue tumors and the added value of MRI: how I do it

This review outlines a practical approach to the everyday assessment of both non-neoplastic and neoplastic soft tissue tumors, focusing on ultrasound examination, though emphasizing the added benefit of magnetic resonance imaging in certain instances. Ultrasound approach and assessment, practical scenarios, reporting, biopsy, and follow-up are covered, as well as the criteria used to distinguish benign from malignant tumors. The potential benefits and current limitations of elastography and contrast-enhanced ultrasound in assessment are also addressed. Examples of commonly encountered soft tissue tumors are shown. Ultrasound can characterize most soft tissue masses based on their ultrasound appearance alone. Following ultrasound examination, three potential scenarios usually exist in clinical practice: (a) confident regarding diagnosis, (b) indeterminate mass with no evidence of malignancy, and (c) indeterminate mass with possibility of malignancy. A diagnostic pathway for each of these scenarios is provided. Magnetic resonance imaging is generally not helpful in further characterizing masses which are indeterminate on ultrasound assessment, though it is helpful in addressing other issues such as exact tumor location and neurovascular bundle involvement that may not be fully resolved on ultrasound examination. In these situations, magnetic resonance imaging examination can be tailored to address those specific questions that have not been adequately addressed on ultrasound examination. In this sense, both examinations are highly complementary. Tips for undertaking magnetic resonance imaging examinations are provided.

Key Points to Select a Device for Dermatologic Ultrasound

What points to consider when selecting a device for practicing dermatologic ultrasound is an excellent question. After we met the requisites published in the guidelines for practicing dermatologic ultrasound, it is necessary to consider the main objective of the use because it is not the same to be focused mostly on the avoidance of the puncture of important facial vessels such as the case of injectors of cosmetic fillers in comparison to the use of operators that need to deal with the diagnosis and monitoring of a wide range of dermatologic pathologies. Currently, a broad variety of ultrasound devices meets the minimum requirements for practicing these examinations in the market. Thus, small, portable, and high-end devices may present advantages and limitations that must be balanced according to the primary purposes and the budget. Moreover, the shape and footprint of the probes can make difficult or facilitate a dermatologic procedure. Other points to consider are the type of storage and the need for technical service. In summary, there are key points that we need to consider when we select a dermatologic ultrasound device in dermatology or aesthetics.

Giant thigh glomus tumor of uncertain malignant potential: Case report with pathologic-radiologic correlation

INTRODUCTION

Glomus tumors (GT) are rare, benign tumors that arise from glomus bodies and usually develop in digital areas. Extradigital GT are exceptional and thigh location is infrequent.

CASE REPORT

We report a case of a GT of the thigh in a 79-year-old male patient that measured 9.5 cm in maximum size. The GT lay above the muscular fascia without infiltrating it. Internal hypervascularity was seen by spectral Doppler ultrasound. Magnetic resonance image showed a heterogeneous mass with hyperintense and hypointense components and internal lobes with liquid-liquid levels. Histopathology revealed a monotonous round-cell proliferation with central nuclei without atypia or mitotic figures, around small-caliber vessels. These cells expressed smooth muscle actin and pericellular collagen IV. GT of uncertain malignant potential was diagnosed. The mass was completely removed. The patient did not experience local relapse nor distant metastasis.

CONCLUSION

GT are rare soft tissue tumors whose diagnosis of unusual giant masses in uncommon locations may be delayed and misdiagnosed given the low suspicion.

Clinical, Dermoscopic, Ultrasonographic, and Histopathologic Correlations in Kaposi's Sarcoma Lesions and Their Differential Diagnoses: A Single-Center Prospective Study

(1) Background: Kaposi's sarcoma (KS) is an angioproliferative neoplasm typically appearing as angiomatous patches, plaques, and/or nodules on the skin. Dermoscopy and ultrasonography have been suggested as an aid in the diagnosis of KS, but there is little evidence in the literature, especially regarding its possible differential diagnoses. Our aim is to describe and compare the clinical, dermoscopic, and ultrasonographic features of KS and KS-like lesions. (2) Methods: we conducted a prospective study on 25 consecutive patients who were first referred to our tertiary care center from January to May 2021 for a possible KS. (3) Results: 41 cutaneous lesions were examined by means of dermoscopy, Doppler ultrasonography, and pathology, 32 of which were KS-related, while the remaining 9 were lesions with clinical resemblance to KS. On dermoscopy, a purplish-red pigmentation, scaly surface, and the collarette sign were the most common features among KS lesions (81.3%, 46.9%, and 28.1%, respectively). On US, all 9 KS plaques and 21 KS nodules presented a hypoechoic image. Dermoscopic and Doppler ultrasonographic findings of KS-like lesions, such as cherry angioma, venous lake, glomus tumor, pyogenic granuloma, and angiosarcoma were also analyzed. (4) Conclusions: dermoscopy and Doppler ultrasonography can be useful to better assess the features of KS lesions and in diagnosing equivocal KS-like lesions.

Extradigital Glomus Tumor of the Forearm Identified During Neuromuscular Ultrasound: A Case Report

Glomus tumors are rare benign soft tissue tumors that arise from the glomus body. They typically develop in the subungual region but may develop extradigitally anywhere, in the upper or lower limbs. Extradigital glomus tumors can be misdiagnosed for years because of their atypical position and presentation. Being aware of an extradigital glomus tumor is important because they can be encountered during imaging studies and may be the cause of the patient’s symptoms. This report presents a case of an extradigital glomus tumor, of the forearm, diagnosed during neuromuscular sonography, in a patient with chronic intractable neuropathic-like pain, along the medial side of the left forearm. Sonographic imaging of the nerves, muscles, and tendons did not reveal any abnormalities. However, meticulous imaging of all tissue layers detected a subcutaneous vascular nodule. Subsequent excision biopsy and histopathologic assessment revealed a glomus tumor. After surgery, the patient experienced dramatic relief of pain. This case report highlights the importance of careful sonographic examination of all the tissues, including skin and subcutaneous tissue layers, to avoid missing non-neuromuscular pathologies that impact patient’s management.

Concepts, Role, and Advances on Nail Imaging

This review discusses, from a practical point of view, the most common imaging techniques and their applications in nail pathologies with some technical considerations. There are several imaging techniques for studying the nail, and all of them require proper devices and trained operators. The highest axial resolution and a more extensive range of applications are provided by ultrasound, which currently is the first-choice imaging technique for evaluating nail conditions. A correlation of state-of-the-art clinical and imaging figures supports the review of this topic.

Diagnosis of Subungual Glomus Tumors with 18 MHz Ultrasound and CDFI

To evaluate the imaging features of subungual glomus tumors using 18 MHz high-frequency ultrasound with CDFI (Color Doppler Flow Imaging). 20 patients treated by surgical resection and examined by ultrasound between January 2008 and December 2019. All eligible cases are divided into two groups: Group A used the probe frequency of 9–14 MHz from January 2008 to December 2014, and Group B used the probe frequency of 18 MHz from January 2015 to December 2019. Patient demographics, clinical records, pathologic specimens and sonography features were reviewed. 50% of tumors in Group A and 100% of tumors in Group B showed clear boundary and regular shape. Blood flow signals were identified inside 50% tumors in Group A (3 in 6), all 14 cases with blood flow signals detected in Group B (14 in 14,100%). 2 cases were misdiagnosed and 1 case escaped diagnosis in Group A, no case was misdiagnosed in Group B. The accuracy of diagnosis rate of Group B is significantly higher than that of Group A. 18-MHz ultrasound combined with CDFI may be a practical useful tool for detecting subungual glomus tumors. More importantly 18-MHz ultrasound can obviously improve the diagnostic accuracy.

Ultrasound features of the subungual glomus tumor and squamous cell carcinomas

BACKGROUND

Nail tumors often pose a significant challenge for the clinician, as they are burdened by a high delay in diagnosis and paucity of clinical signs in the early stage. In most cases, the onset of pain or nail plate dystrophy leads to imaging investigations such as plain radiography, magnetic resonance imaging, and ultrasonography (US) when surgery is pending.

MATERIAL AND METHODS

A 2-year monocentric study evaluated the histologically confirmed cases of subungual glomus tumor (GT) and squamous cell carcinoma (SCC) with a pre-surgical US assessment, and reviewed their sonography features. A total of 7 digital GTs and 6 SCCs of the nail were collected.

RESULTS

GT and SCC are easily distinguishable on US. Compared to SCC, GT was positively associated with an ovoid shape, well-defined borders, bone cup-scalloping without cortical erosion, and a rich intralesional vascular pattern (P < 0.05). Vice versa, SCC was significantly correlated with irregular shape, ill-circumscribed margins, an infiltrative growth pattern with peripheral hypoechoic foci, posterior acoustic shadow, cortical erosion, and a highly vascular multipolar peripheral pattern (P < 0.05).

CONCLUSION

The rapid assessment of GT and SCC sonographic features may contribute to reduce diagnostic delay, expedite management, and decrease the risk of surgical relapse.

Accuracy of ultrasound in the characterization of superficial soft tissue tumors: a prospective study

OBJECTIVE

To prospectively evaluate the accuracy of ultrasound in defining the specific nature of superficial soft tissue masses as well as determining malignancy.

MATERIALS AND METHOD

Eight hundred twenty-three superficial soft tissue masses were prospectively evaluated with ultrasound by one of five experienced musculoskeletal radiologists. The radiologist at the time of examination provided one to three specific differential diagnoses and the perceived level of confidence with regard to each diagnosis. Clinical and ultrasound diagnoses were compared with the histological diagnosis to determine accuracy. Tumor malignancy was determined by histology or clinical/imaging follow-up.

RESULTS

Histological correlation was present for 219 (26.6%) of the 823 masses. Compared with histology, the accuracy of clinical and ultrasound examination for determining specific tumor type was 25.6% and 81.2% respectively considering all differential diagnoses provided. Radiologists were "fully confident" with the ultrasound diagnosis in 585 (71.1%) of 823 masses overall. In this setting, when compared with histology, the diagnostic accuracy of ultrasound was 95.5%. When the radiologist was "not fully confident," accuracy was 41.3% for the first differential diagnosis and 60.9% for all differential diagnoses. Diagnostic accuracy improved with increasing radiologist experience. Sensitivity, specificity, positive predictive value, and negative predictive value of ultrasound for identifying malignant tumor were 93.3%, 97.9%, 45.2%, and 99.9% respectively.

CONCLUSIONS

One can be "fully confident" at characterizing over two-thirds of superficial soft tissue masses based on ultrasound appearances and, in this setting, diagnostic accuracy is very high. Ultrasound examination is also highly accurate at discriminating benign from malignant superficial soft tissue masses.

High-Resolution Ultrasound Visualization of Pacinian Corpuscles

The aim of this study was to evaluate the possibility of visualizing Pacinian corpuscles in the palm of the hand with high-resolution ultrasound (HRUS). In this prospective study, HRUS with a high-frequency probe (22 MHz) was used. The palms of two fresh cadaveric hands were screened for potential Pacinian corpuscles. Still ultrasound images and dynamic video sequences were obtained. In five regions with large amounts of suspected Pacinian corpuscles, tissue blocks were excised and histologically processed, and corresponding slices were compared with ultrasound images. Further, the transverse diameters of five Pacinian corpuscles, at the level of the metacarpal heads in the palm, were assessed on both sides (in total 100) in healthy volunteers. On ultrasound, Pacinian corpuscles presented as echolucent dots in the subcutis, adjacent to digital nerves and vessels and located 2-3 mm beneath the surface. On histologic sections, these echolucent dots corresponded to Pacinian corpuscles with respect to their position and topographic relationships. The mean transverse diameter for all volunteers was 1.40 ± 0.23 mm (range: 0.8-2.2 mm). This study confirms the ability to reliably visualize Pacinian corpuscles with HRUS, which contributes to our basic understanding of ultrasonographically visible subcutaneous structures and may enhance the diagnosis of pathologies related to Pacinian corpuscles.

Hypervascular Pseudonodular Plaque-Like Ultrasound Morphology in Angiolymphoid Hyperplasia

Angiolymphoid hyperplasia with eosinophilia (ALHE) is a benign vascular proliferation characterized by solitary or multiple angiomatous lesions. It is most common in young or middle-aged women, and the lesions typically affect the head and neck, showing a particular predilection for the periauricular region. The differential diagnosis in patients with ALHE is broad and includes both benign and malignant conditions. We report on a series of cases of periauricular ALHE in which ultrasound imaging revealed an hypervascular, pseudonodular and plaque-like morphology with clinical and histologic correlations. It also evidenced vascular communication between lesions that appeared to be separate on clinical examination. Familiarity with such ultrasound presentations could help to improve diagnostic accuracy and facilitate disease monitoring in patients with ALHE.

Color Doppler Ultrasound Study of Glomuvenous Malformations with its Clinical and Histologic Correlations

Glomuvenous malformations are hamartomatous lesions characterized by the presence of glomus cells in the vascular smooth muscle. We present the clinical and color Doppler ultrasound features of a series of 13 cases of histologically confirmed glomuvenous malformations. In all cases, the ultrasound study revealed moderately delimited superficial dermal and hypodermal pseudonodular structures of mixed echogenicity, with hypoechoic and heterogeneous areas and anechoic, pseudocystic tubular and lacunar zones. Arterial and venous vessels, mainly with a low flow (≤ 15cm/s) were observed in 85% of patients, but no arteriovenous shunts were present. Deeper structures were not affected and no phleboliths were detected. The clinical and ultrasound findings could facilitate diagnosis, surgical planning, and noninvasive follow-up in these tumors.