Giant cell tumors of the tendon sheath may present radiologically as intrinsic osseous lesions

Diffuse-Type Tenosynovial Giant Cell Tumor: What Are the Important Findings on the Initial and Follow-Up MRI?

Tenosynovial giant cell tumor (TSGCT) is a rare soft tissue tumor that involves the synovial lining of joints, bursae, and tendon sheaths, primarily affecting young patients (usually in the fourth decade of life). The tumor comprises two subtypes: the localized type (L-TSGCT) and the diffuse type (D-TSGCT). Although these subtypes share histological and genetic similarities, they present a different prognosis. D-TSGCT tends to exhibit local aggressiveness and a higher recurrence rate compared to L-TSGCT. Magnetic resonance imaging (MRI) is the preferred diagnostic tool for both the initial diagnosis and for treatment planning. When interpreting the initial MRI of a suspected TSGCT, it is essential to consider: (i) the characteristic findings of TSGCT-evident as low to intermediate signal intensity on both T1- and T2-weighted images, with a blooming artifact on gradient-echo sequences due to hemosiderin deposition; (ii) the possibility of D-TSGCT-extensive involvement of the synovial membrane with infiltrative margin; and (iii) the resectability and extent-if resectable, synovectomy is performed; if not, a novel systemic therapy involving colony-stimulating factor 1 receptor inhibitors is administered. In the interpretation of follow-up MRIs of D-TSGCTs after treatment, it is crucial to consider both tumor recurrence and potential complications such as osteoarthritis after surgery as well as the treatment response after systemic treatment. Given its prevalence in young adult patents and significant impact on patients' quality of life, clinical trials exploring new agents targeting D-TSGCT are currently underway. Consequently, understanding the characteristic MRI findings of D-TSGCT before and after treatment is imperative.

Giant cell tumour of the tendon sheath of the spine: clinical features and imaging findings

Objectives

To review the clinical and imaging data of spinal giant cell tumour of the tendon sheath (GCTTS) to improve our understanding of the disease.

Methods

The imaging findings, clinicopathological features and clinical outcomes of 14 patients with pathologically confirmed spinal GCTTS were analysed retrospectively.

Results

All 14 patients had a single spinal lesion, including ten cervical vertebra lesions and four thoracic vertebra lesions. CT scan findings: The lesions showed osteolytic bone destruction and were centred on the facet joint, eroding the surrounding bone with a paravertebral soft tissue mass. MRI scan findings: all the lesions manifested predominantly as isointense or hypointense on T1-weighted imaging (T1WI). On T2-weighted imaging (T2WI), eight lesions were hypointense, and four were isointense. The remaining two lesions showed slight hyperintensity. The enhanced scans of eight lesions showed moderate to marked homogeneous or heterogeneous enhancement. PET/CT findings: Among the five patients who underwent PET/CT, three presented lesions with well-defined, sclerotic borders, and the uptake of ¹⁸F-FDG was markedly increased. One lesion showed an ill-defined border and an uneven increase in ¹⁸F-FDG uptake with an SUVmax value of 8.9. A recurrent lesion was only found on PET/CT 45 months after surgery and the SUVmax was 5.1.

Conclusions

Spinal GCTTS is extremely rare. Osteolytic bone destruction in the area of the facet joint with a soft tissue mass and hypointensity on T2WI images are indicative of the spinal GCTTS. GCTTS shows high uptake of ¹⁸F-FDG, and PET/CT is helpful in detecting recurrent lesions.

Tenosynovial Giant Cell Tumor in the Forefoot: Two Case Reports and Literature Review

Tenosynovial giant cell tumor is the common term used to describe a group of soft-tissue tumors that share a common etiologic link. These tumors are relatively infrequent in the foot and ankle, and occasionally they may be the cause of destruction of the adjacent bone structures. We report the imaging appearance and pathologic findings of two patients with localized tenosynovial giant cell tumor of the forefoot. Both of these patients underwent surgical gross total resection. However, one of the patients experienced a recurrence. Their clinical, radiologic, and pathologic features, with their treatment protocol, are summarized retrospectively, and related literature is reviewed in an attempt to enhance the understanding of these tumor lesions. Clinicians should perform a careful preoperative and postoperative examination and complete tumor surgical resection with the aim of reducing local recurrence.

Imaging of Soft Tissue Tumors

Differentiation of malignant from benign soft tissue tumors is challenging with imaging alone, including that by magnetic resonance imaging and computed tomography. However, the accuracy of this differentiation has increased owing to the development of novel imaging technology. Detailed patient history and physical examination remain essential for differentiation between benign and malignant soft tissue tumors. Moreover, measurement only of tumor size based on Response Evaluation Criteria In Solid Tumors criteria is insufficient for the evaluation of response to chemotherapy or radiotherapy. Change in metabolic activity measured by ¹⁸F-fluorodeoxyglucose positron emission tomography or dynamic contrast enhanced-derived quantitative endpoints can more accurately evaluate treatment response compared to change in tumor size. Magnetic resonance imaging can accurately evaluate essential factors in surgical planning such as vascular or bone invasion and "tail sign". Thus, imaging plays a critical role in the diagnosis and treatment of soft tissue tumors.

[Foot and ankle tumours : Part II: Malignant bone tumours and soft tissue tumours of the foot with differential diagnostic hints]

CLINICAL ISSUE

Both benign and malignant tumours are encountered in the foot and ankle. Due to their rarity, however, diagnosis is often uncertain. Usual criteria such as tumour size, invasiveness or pain fail to differentiate benign from malignant neoplasias.

STANDARD RADIOLOGICAL METHODS

Plain radiography and-due to the complex foot anatomy-CT are important in the diagnostic evaluation of primary bone tumours. In the case of soft tissue tumours, ultrasonography is used to identify ganglion cysts. Tumour evaluation and staging are then performed using MRI. Nuclear imaging comes into play when multifocal, metastatic or systemic spread of the disease is suspected or if a biopsy procedure is planned.

METHODICAL INNOVATIONS

For the role of dual-energy CT, please refer to part I. Whether dual-energy CT is suitable to assess bone marrow oedema patterns is still debated.

SPECIAL FEATURES OF FOOT AND ANKLE TUMOURS

Primary bone tumours generally present in the ankle or the hindfoot. Malignant bone tumours, e. g. chondrosarcoma, are primarily found in the latter. On the other hand, soft tissue tumours generally present in the mid- and forefoot regions.

ACHIEVEMENTS

While the radiologic diagnostic evaluation of pedal bone tumours is quite reliable, caution is urgently needed in the case of soft tissue tumours because there are many confusing differential diagnoses.

PRACTICAL RECOMMENDATIONS

Proper X‑ray examination of the foot (at least in two plains) or with special views according to bony pathology is needed. All soft tissue masses that are not cysts should be evaluated further. MRI remains the diagnostic modality of choice but never stands alone! Caution: Size and well-defined margins of pedal soft tissue tumours are not considered criteria regarding whether a tumour is malignant or not.

Coexistence of giant cell tumor of tendon sheath and enchondroma in the middle phalanx of the little finger mimicking a malignant tumor: A case report

Giant cell tumor of the tendon sheath is a type of slow-growing benign soft tissue tumor that typically arises from the synovium of the tendon sheath. Enchondroma is a benign bone tumor comprising of mature hyaline cartilage that centrally develops within the tubular bone. While giant cell tumor of the tendon sheath or enchondroma are common benign soft tissue and bone tumors, respectively the simultaneous occurrence of these tumors in the same region of the hand is exceedingly rare, and it can mimic a malignant tumor, thereby making the diagnosis more challenging. Herein, we report an unusual imaging presentation of the coexistence of these tumors in the middle phalanx of the little finger, which to the best of our knowledge has not been previously reported, and this initially present as a single intrinsic osseous lesion mimicking malignancy. The coexistence of these tumor types must be considered in the differential diagnosis of an intramedullary lytic lesion with a poor margin associated with a soft tissue mass of the fingers, and a meticulous preoperative magnetic resonance imaging investigation was required.

Characteristics, Management Techniques, and Outcomes of the Most Common Soft-Tissue Hand Tumors: A Literature Review and Our Experience

INTRODUCTION

Diagnosis of the hand's soft-tissue tumors is often difficult because of the different anatomic structures present in this region and yet clinicians must be able to distinguish typical benign entities from life-threatening or limb-threatening malignant diseases.

MATERIALS AND METHODS

At the Department of Plastic and Reconstructive Surgery at the University of Palermo, 629 patients with hand tumors were studied. Treatment was surgical for all of them; also radiotherapy and chemotherapy were necessary based on the histological diagnosis.

CONCLUSIONS

Our retrospective study with a literature review aims to present the most commonly observed soft-tissue hand lesions, analyzing their causes, their objective and instrumental evaluation, and their treatments.

[Giant cell tumors of the tendon sheaths of the hand: about 50 cases]

Giant cell tumors of the synovial tendon sheaths (GCTSTS) are a localized form of hemopigmented villonodular synovitis. They mainly affect the hands. This study aims to analyse the epidemiology, clinical and therapeutic characteristics of GCTSTS, to assess the results of surgical treatment and to identify risk factors for recurrences. We conducted a retrospective data collection from medical records of 50 patients with GCTSTS of the hand between 1992 and 2016 in the Department of Orthopaedics at the Hospital of Sahloul (Sousse-Tunisia). The clinical and epidemiological features of GCTSTS have been specified. The average age of patients was 33 years (9-69 years), the sex ratio was 0,6. Constant swelling (100%), joints inter-phalangeal mobilization trouble (6%) and digital pain (18%) were the most frequent reason for consultation. All tumors were located at the level of the digital region, especially at the level of the index (42%). It occurred on the palm of the hand in 66% of cases. All patients underwent surgery; macroscopically GCTTS appeared as an encapsulated polylobed and yellowish brown tumor, extending into the flexor tendons sheath(4 cases) and under the extensor tendon (2 cases). We noted a single case of recurrent cancer (2%) which was treated surgically. The functional results were good in all cases. The diagnosis of GCTTS should be evoked when there is evidence of digital swelling. Their management is based on surgery which is difficult and should be performed correctly to avoid recurrences.

Lung metastases of diffuse giant cell tumour of the fibular tendon sheath at the ankle: A case report

Diffuse giant cell tumours of the tendon sheaths are described in the literature as locally aggressive soft-tissue tumours. We report the case of a 56-year-old male with a history of multiple surgical procedures for a giant cell tumour of the fibular tendon sheath at the right ankle. The multiple recurrences prompted monitoring by positron-emission tomography, which showed lung tumours. Biopsies confirmed that the tumours were metastases from the giant cell tumour of the tendon sheath. In patients with recurrent and/or diffuse giant cell tumour, positron-emission tomography is an effective monitoring tool.

The clinical approach toward giant cell tumor of bone

We provide an overview of imaging, histopathology, genetics, and multidisciplinary treatment of giant cell tumor of bone (GCTB), an intermediate, locally aggressive but rarely metastasizing tumor. Overexpression of receptor activator of nuclear factor κB ligand (RANKL) by mononuclear neoplastic stromal cells promotes recruitment of numerous reactive multinucleated giant cells. Conventional radiographs show a typical eccentric lytic lesion, mostly located in the meta-epiphyseal area of long bones. GCTB may also arise in the axial skeleton and very occasionally in the small bones of hands and feet. Magnetic resonance imaging is necessary to evaluate the extent of GCTB within bone and surrounding soft tissues to plan a surgical approach. Curettage with local adjuvants is the preferred treatment. Recurrence rates after curettage with phenol and polymethylmethacrylate (PMMA; 8%-27%) or cryosurgery and PMMA (0%-20%) are comparable. Resection is indicated when joint salvage is not feasible (e.g., intra-articular fracture with soft tissue component). Denosumab (RANKL inhibitor) blocks and bisphosphonates inhibit GCTB-derived osteoclast resorption. With bisphosphonates, stabilization of local and metastatic disease has been reported, although level of evidence was low. Denosumab has been studied to a larger extent and seems to be effective in facilitating intralesional surgery after therapy. Denosumab was recently registered for unresectable disease. Moderate-dose radiotherapy (40-55 Gy) is restricted to rare cases in which surgery would lead to unacceptable morbidity and RANKL inhibitors are contraindicated or unavailable.

Giant cell tumor of the tendon sheath mimicking a primary intramedullary metatarsal tumor

Giant cell tumor of the tendon sheath (GCTTS) is one of the most common benign soft tissue tumors in the extremities, and is frequently associated with bone abnormalities. Although extrinsic bone erosion is the most common bone abnormality associated with GCTTS, intraosseous invasion of GCTTS occurs rarely and may mimic a primary bone tumor, making diagnosis more challenging. We report an unusual imaging presentation of GCTTS mimicking a primary intramedullary metatarsal tumor and review the literature on the frequency of bone involvement of GCTTS.

EXCISION OF GIANT CELL TUMOR OF TENDON SHEATH WITH BONE INVOLVEMENT BY MEANS OF DOUBLE ACCESS APPROACH: CASE REPORT

Giant cell tumors of the tendon sheath are common lesions and are the second most frequent tumors in the hand, after synovial cysts. They are diagnosed by means of clinical examination and complementary examinations (simple radiography and magnetic resonance). Erosion and invasion of the phalangeal bone affected may be seen on radiological examination. Magnetic resonance may show a "fluorescent or radiant effect" may be observed, caused by the high quantity of hemosiderin inside the tumor. Surgical treatment is the commonest practice, and complete excision is important for avoiding recurrence of the tumor, especially when bone invasion is observed on imaging examinations, which is generally related to greater tumor recurrence. In this paper, a case of a giant cell tumor of the tendon sheath in the middle phalanx of the third finger of a 45-year-old female patient is presented. This was successfully treated by means of surgery using a double access approach (dorsal and volar).

Imaging of giant cell tumour of the tendon sheath

Giant cell tumours of the tendon sheath (GCTTS) and pigmented villonodular synovitis (PVNS) are part of a spectrum of benign proliferative lesions of synovial origin that may affect the joints, bursae and tendon sheaths. This review article describes the clinicopathological features and imaging findings in patients with GCTTS. GCTTS usually presents as a soft tissue mass with pressure erosion of the underlying bone. Magnetic resonance (MR) imaging of GCTTS typically shows low to intermediate signal on T1- and T2-weighted spin-echo sequences due to the presence of haemosiderin, which exerts a paramagnetic effect. On gradient-echo sequences, the paramagnetic effect of haemosiderin is further exaggerated, resulting in areas of very low signal due to the blooming artefact. Ultrasonography shows a soft mass related to the tendon sheath that is hypervascular on colour or power Doppler imaging.

[Giant cell tumor of the tendon sheath: characteristic findings of the bone scintigraphy and correlation with MRI]

We report 3 cases of an unusual tumor, that is, the giant cell tumor of the tendon sheath. The patients consulted due to the appearance of a well-defined, painless, soft tissue mass with mild-to-moderate inflammation located in the thumbs or toes. These clinical data, together with the bone scan findings, oriented the diagnostic suspicion that was confirmed by a pathology study of the tumor after resection. This work has aimed to review the characteristics of the bone scan (BS) image of this tumor and its correlation with the conventional X-ray imaging and magnetic resonance imaging (MRI).