Campanacci Grade 2 or 3 Giant Cell Tumor of the Phalanges: En Bloc Resection and Matched Nonvascularized Toe Phalangeal Transfer.

PURPOSE: The goal of the study was to assess the result of en bloc resection and matched nonvascularized toe phalangeal transfer in Campanacci grade 2 or 3 giant cell tumors of the phalanges. METHODS: Seven patients with Campanacci grade 2 and 3 phalangeal giant cell tumors were treated by en bloc resection and matched nonvascularized toe phalangeal transfer between June 2004 and May 2021. The patients were followed up by X-rays, Patient-Rated Hand and Wrist scores, Foot Function Index, Quick Disabilities of the Arm, Shoulder, and Hand questionnaire, and total active motion measurements. RESULTS: The minimum follow-up was 18 months (range: 18-230 months; mean: 110 ± 81). There were three males and four females, with age ranging from 13 to 48 years (mean: 24.14 ± 11.74). The right:left hand ratio was 3:4. The thumb was involved in one patient, the index finger in two, the middle finger in one, and the ring finger in three patients. The mean total active motion was 201.70 (range: 190°-240°). The mean patient-rated hand and wrist score was 15.2 (range: 10-35). The mean quick disabilities of the arm, shoulder and hand questionnaire score was 1.3 (range: 0-9). The mean foot function index on follow-up was 2.86 (range: 2-3). There was no tumor recurrence. One patient had a pathological fracture with resultant shortening of the finger on follow-up. CONCLUSIONS: In our series en bloc resection and matched nonvascularized toe phalangeal transfer resulted in a functional tumor-free digit with a low complication rate and no recurrences. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic V.

The clinical significance of CD44v6 in malignant and benign primary bone tumors.

BACKGROUND: The objective of this study was to assess the expression profile of CD44v6, a potential cancer stem cell marker, and its diagnostic and predictive significance in three distinct types of primary bone tumors. METHODS: In this study, we utilized real-time qRT-PCR and immunohistochemistry to examine the gene and protein levels of CD44v6 in a total of 138 fresh bone tissues. This included 69 tumor tissues comprising osteosarcoma (N = 23), chondrosarcoma (N = 23), and GCT (N = 23), as well as 69 corresponding non-cancerous tumor margins. Furthermore, we investigated the circulating level of CD44v6 by isolating peripheral blood mononuclear cells from 92 blood samples. Among these, 69 samples were obtained from patients diagnosed with primary bone tumors, while the remaining 23 samples were from healthy donors. The primary objectives of our investigation were to assess the correlation between CD44v6 expression levels and clinic-pathological features of the patients, as well as to evaluate the diagnostic and predictive values of CD44v6 in this context. RESULTS: In patients with osteosarcoma and chondrosarcoma tumors, both the gene and protein expression of CD44v6 were found to be significantly higher compared to the GCT group. Furthermore, the circulating level of CD44v6 was notably elevated in patients diagnosed with osteosarcoma and chondrosarcoma in comparison to the GCT group and patients with malignant tumor characteristics. Additionally, we observed a strong correlation between the gene and protein levels of CD44v6 and important tumor indicators such as tumor grade, metastasis, recurrence, and size at the tumor site. CD44v6 shows potential in differentiating patients with bone tumors from both control groups and tumor groups with severe and invasive characteristics from those with non-severe features. Importantly, the expression level of CD44v6 also demonstrated predictive value for determining tumor grade and the likelihood of recurrence. CONCLUSION: CD44v6 is likely to play a role in the development of primary bone tumors and has the potential to serve as a diagnostic biomarker for bone cancer. However, to obtain more accurate and conclusive findings, further mechanistic investigations involving larger population samples are necessary.

Bone and soft tissue tumors: clinicoradiologic-pathologic molecular-genetic correlation of novel fusion spindled, targetable-ovoid, giant-cell-rich, and round cell sarcomas.

BACKGROUND: New entities in the classification of bone and soft tissue tumors have been identified by use of advanced molecular-genetic techniques, including next-generation sequencing. Clinicoradiologic and pathologic correlation supports diagnostic classification. METHODS: Tumors from four morphologically grouped areas are selected to enhance diagnosis and awareness among the multidisciplinary team. These include select round cell tumors, spindle cell tumors, targetable tyrosine kinase/RAS::MAPK pathway-ovoid (epithelioid to spindled) tumors, and giant-cell-rich tumors of bone and soft tissue. RESULTS: Round cell tumors of bone and soft tissue include prototypical Ewing sarcoma, newer sarcomas with BCOR genetic alteration and CIC-rearranged, as well as updates on FUS/EWSR1::NFATc2, an EWSR1 non-ETS tumor that is solid with additional amplified hybridization signal pattern of EWSR1. This FUS/EWSR1::NFATc2 fusion has now been observed in seemingly benign to low-grade intraosseous vascular-rich and simple (unicameral) bone cyst tumors. Select spindle cell tumors of bone and soft tissue include rhabdomyosarcoma with FUS/EWSR1::TFCP2, an intraosseous high-grade spindle cell tumor without matrix. Targetable tyrosine-kinase or RAS::MAPK pathway-tumors of bone and soft tissue include NTRK, ALK, BRAF, RAF1, RET, FGFR1, ABL1, EGFR, PDGFB, and MET with variable ovoid myopericytic to spindled pleomorphic features and reproducible clinicopathologic and radiologic clues to their diagnosis. Giant-cell-rich tumors of bone, joint, and soft tissue are now respectively characterized by H3F3A mutation, CSF1 rearrangement (targetable), and HMGA2::NCOR2 fusion. CONCLUSION: This article is an update for radiologists, oncologists, surgeons, and pathologists to recognize these novel ovoid, spindled, giant-cell-rich, and round cell tumors, for optimal diagnostic classification and multidisciplinary team patient care.

Giant cell tumor of soft tissue of the colon: a case report and review of the literature.

BACKGROUND: A giant cell tumor (GCT) is a benign neoplasm characterized by mixture of mononuclear cells and multinucleated cells. A GCT of soft tissue (GCT-ST) is developed in various extraosseous sites, but GCT-ST of the gastrointestinal tract is very rare. GCT-ST usually has a benign course, but rare cases reported malignant potential of the tumor. Therefore, complete resection is required to prevent local recurrence or distant metastasis. CASE PRESENTATION: A 53-year-old woman was admitted for follow-up colonoscopy who underwent the colorectal endoscopic submucosal dissection (ESD) of a laterally spreading tumor at the hepatic flexure 6 months ago. A colonoscopy showed a polypoid mass about 3.5 × 2.5 cm at the previous ESD site. As endoscopic finding showed a smooth multi-nodular tumor without submucosal invasion, we performed endoscopic mucosal resection. Based on pathological and immunohistochemical findings, the lesion was diagnosed as a GCT-ST in the colon. Follow-up colonoscopy performed 6 months later revealed no evidence of recurrence. CONCLUSION: This is the first report of a GCT-ST identified in the colon. Although GCT-ST generally has a benign clinical course, complete resection should be performed to prevent local recurrence and metastasis.

Up-regulation of matrix metalloproteinase-9 in primary bone tumors and its association with tumor aggressiveness.

BACKGROUND: Understanding the molecular mechanism underlying the pathophysiology of primary skeletal tumors is crucial due to the tumor-related complications, incidence at a young age, and tumor recurrence. METHODS AND RESULTS: The local expression pattern of MMP-9 as an active matrix-degrading protease was detected in 180 bone tissues, including 90 tumors and 90 noncancerous tissues, utilizing real-time qRT-PCR at the mRNA level and immunohistochemistry at the protein level. The correlation of the MMP-9 expression level with the patient's clinical pathological characteristics and the aggressiveness of the tumor was evaluated. The diagnostic significance of MMP-9 and the model of association of variables and MMP-9 expression and their predictive values were determined. Mean mRNA expression was higher in all types of primary bone tumors than their paired non-cancerous tissues. Osteosarcoma and Ewing's sarcoma expressed higher levels of MMP-9 compared to benign giant cell tumors, and the MMP-9 expression level was significantly correlated with the size, metastasis, and recurrence of the malignant tumor. A consistent expression pattern was demonstrated for MMP-9 protein levels in tissues. In addition, the MMP-9 gene and protein levels significantly discriminate between bone tumors and normal tissue, as well as benign and malignant tumors, and could predict potentially malignant traits such as tumor grade and metastasis. CONCLUSIONS: The data propose that MMP-9 may be involved in the proliferation and invasion of primary bone tumors and has the potential to monitor and treat the progression of malignant tumors.

Histone H3G34 Mutation in Brain and Bone Tumors.

H3G34 mutations occur in both pediatric non-brainstem high-grade gliomas (G34R/V) and giant cell tumors of bone (G34W/L). Glioblastoma patients with G34R/V mutation have a generally adverse prognosis, whereas giant cell tumors of bone are rarely metastatic benign tumors. G34 mutations possibly disrupt the epigenome by altering H3K36 modifications, which may involve attenuating the function of SETD2 at methyltransferase. H3K36 methylation change may further lead to genomic instability, dysregulated gene expression pattern, and more mutations. In this chapter, we summarize the pathological features of each mutation type in its respective cancer, as well as the potential mechanism of their disruption on the epigenome and genomic instability. Understanding each mutation type would provide a thorough background for a thorough understanding of the cancers and would bring new insights for future investigations and the development of new precise therapies.

Giant cell tumors of the mobile spine with invasion of adjacent vertebrae: an unusual imaging finding.

BACKGROUND: Giant cell tumors of the mobile spine invasion of the adjacent vertebrae are an ignored imaging finding. METHODS: Nine patients with giant cell tumors of the mobile spine with invasion of the adjacent vertebrae confirmed by pathology were enrolled. Eight patients had pure giant cell tumors (GCTs), while one patient also had an aneurysmal bone cyst. All patients underwent conventional computed tomography, three-dimensional reconstruction, and conventional magnetic resonance imaging, while seven patients also underwent post-contrast magnetic resonance imaging. RESULTS: All patients showed GCTs of the mobile spine that arose from the vertebral body and extended to the vertebral arch. The tumors showed soft-tissue attenuation with no evidence of a mineralized matrix. Pathological fracture was seen in five patients. The margin of the original tumor showed partial sclerosis in four patients and involved an adjacent vertebral body with a sclerotic rim in two patients. The tumors showed a homogeneous and similar signal intensity to the normal spinal cord on T1WI (T1-weighted image) in five patients. The cystic area of the tumors was hyperintense on T2WI in the remaining four patients, while one patient showed hemorrhage that was hyperintense on T1WI. The solid components of the GCTs show marked enhancement in all cases, while the cystic area of the tumors was observed without enhancement on contrast-enhanced images in four patients. Bone destruction of the adjacent vertebral body showed a homogeneous signal on T1WI and T2WI and marked enhancement on contrast-enhanced images. CONCLUSIONS: Giant cell tumors of the mobile spine with invasion into adjacent vertebrae are an unusual imaging finding. Radiologists should be familiar with this imaging characteristic.

18F-fluorodeoxyglucose positron emission tomography/computed tomography in the evaluation of spinal giant cell tumors.

OBJECTIVE: To investigate the value of 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) in the evaluation of spinal giant cell tumors (GCTs). MATERIALS AND METHODS: The PET/CT and clinical data of 16 patients with spinal GCTs were reviewed. The maximal standardized uptake value (SUVmax), longest diameter, and CT features of spinal GCTs were analyzed. The value of PET/CT and MRI in displaying the recurrent lesions was compared. PET Response Criteria in Solid Tumors were adopted to evaluate the response to radiotherapy. RESULTS: Data from 7 males and 9 females (median age 32.5 years) were analyzed. Eight patients had primary GCTs with a median SUVmax of 11.91 and a median length of 4.42 cm. Eight patients had relapsed GCTs with a median SUVmax of 10.34 and a median length of 6.23 cm. There was no statistical difference between the SUVmax of primary and relapsed GCTs. The SUVmax did not correlate with length. In 8 relapsed patients, 4 lesions invaded the vertebral canal, but 2 of which were not displayed on MRI. Metal prostheses showed extremely low signal intensity on MRI, even in the 3 cases with increased intra-prosthetic 18F-FDG concentration. Five relapsed patients with subsequent radiotherapy had a repeat PET/CT. A complete, partial, and stable metabolic response was observed in 1, 3, and 1 patient, respectively. CONCLUSIONS: Both the primary and recurrent spinal GCTs avidly accumulate 18F-FDG. For recurrent GCTs, PET/CT may provide incremental value in the assessment of the vertebral canal and intra-prosthetic involvement and the response to radiotherapy.

Wrist Arthrodesis and Osteoarticular Reconstruction in Giant Cell Tumor of the Distal Radius.

PURPOSE: The aim of this multi-institutional retrospective study was to compare osteoarticular graft reconstruction (OA) and wrist arthrodesis (WA) after distal radius resection for giant cell tumor. MATERIAL AND METHODS: Sixty-seven patients affected by giant cell tumor of the distal radius underwent resection and reconstruction with OA (47 patients) or WA (20 patients). The mean age was 40 years (range, 13-74 years). Grafts included fresh-frozen allograft or nonvascularized fibular autograft. Complications requiring surgical revision were recorded. Clinical outcome was assessed with the Musculoskeletal Tumour Society Score (MSTS) and Disabilities of the Arm, Shoulder, and Hand (DASH) score. RESULTS: Fifteen patients developed a local recurrence after a median of 12 months (range, 6-137 months). Sixteen patients required revision surgery for complications. Of these, 10 were graft-related complications (7 in the OA group and 3 in the WA group). Among OA, 2 patients with painful instabilities and 4 with severe arthritis required conversion into WA after a mean of 26 months (range, 13-38 months) At a median follow-up of 105 months (range, 12-395 months), similar functional outcome (MSTS and DASH score) was observed between OA and WA. CONCLUSIONS: Our results did not show any advantage of OA or WA over the other technique. A patient-by-patient decision should be taken both regarding the type of reconstruction (OA or WA) and the type of graft (allograft or autograft). The reconstructive choice should also consider the patient's functional expectations. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Massively parallel sequencing of tenosynovial giant cell tumors reveals novel CSF1 fusion transcripts and novel somatic CBL mutations.

Tenosynovial giant cell tumor (TSGCT) is a rare neoplasm. Although surgical resection is the widely accepted primary treatment for TSGCT, recurrences are frequent, and patients' joint function may be severely compromised. Previous studies reported that CSF1-COL6A3 fusion genes were identified in approximately 30% of TSGCTs. The aim of our study was to comprehensively clarify the genomic abnormalities in TSGCTs. We performed whole exome sequencing in combination with target sequence validation on 34 TSGCT samples. RNA sequencing was also performed on 18 samples. RNA sequencing revealed fusion transcripts involving CSF1, including novel CSF1-VCAM1, CSF1-FN1 and CSF1-CDH1 fusions, in 13/18 (72%) cases. These fusion genes were validated by chromogenic in situ hybridization. All CSF1 fusions resulted in the deletion of CSF1 exon 9, which was previously shown to be an important negative regulator of CSF1 expression. We also found that 12 (35%) of the 34 TSGCT samples harbored CBL missense mutations. All mutations were detected in exons 8 or 9, which encode the linker and RING finger domain. Among these mutations, C404Y, L380P and R420Q were recurrent. CBL-mutated cases showed higher JAK2 expression than wild-type CBL cases (p = 0.013). CSF1 fusion genes and CBL mutations were not mutually exclusive, and both alterations were detected in six of the 18 (33%) tumors. The frequent deletion of CSF1 exon 9 in the fusion transcripts suggested the importance of this event in the etiology of TSGCT. Our results may contribute to the development of new targeted therapies using JAK2 inhibitors for CBL-mutated TSGCT.

Magnetic resonance imaging features of fibromas and giant cell tumors of the tendon sheath: differential diagnosis.

PURPOSE: The clinical and imaging characteristics of fibromas of the tendon sheath (FTS) closely resemble those of giant cell tumors of the tendon sheath (GCTTS). We aimed to study MRI features of FTS and GCTTS to distinguish the two entities and improve their differential diagnosis. MATERIALS AND METHODS: We retrospectively analyzed data from 18 patients (9 men, 9 women; age, 17-62 years) and 24 patients (13 men, 11 women; age, 15-67 years) treated between May 2011 and May 2016, with histologically confirmed FTS and GCTTS, respectively. Specific MRI features of the two groups were compared using the independent sample t tests and chi-square tests. RESULTS: FTS exhibited round or oval shapes. Proton-weighted images (PDWI) showed heterogeneous hypointensity that appeared striped or disordered and was located in the lesion center. Enhanced scans demonstrated asymmetrical signal in the foci. GCTTS mostly exhibited a lobulated or casting mold pattern, with a hypointense ring on PDWI. The hypointense components appeared granular/flaky or separated, sometimes behaving as a uniform signal on PDWI. Significant differences in the following features were observed between the two groups: lesion morphology (p < 0.001); imaging features on PDWI, including whether the signal is homogeneous (p < 0.001); the presence of a hypointense ring (p = 0.006); the location and morphology of hypointensity (p < 0.001); bone absorption (p = 0.008); enhancing pattern (p = 0.008); and whether the tumor crossed the joint (p = 0.026). CONCLUSIONS: FTS and GCTTS demonstrate distinctive MRI features, which can be used for differential diagnosis with sensitivities, specificities, and diagnostic accuracies of 83-100%, 29-79%, and 60-89%, respectively. KEY POINTS: • Fibromas and giant cell tumors of the tendon sheath have distinct features on MRI, including differences in lesion morphology and intensity patterns, which can be used for differential diagnosis. • Among other signs, GCTTS are more uniform than FTS, and FTS have a striped or disordered pattern. • Tumors were classified with 90% accuracy into either FTS or GCTTS based on a combination of two features: homogenous signal and hypointensity shape on PDWI.

Denosumab: an Emerging Therapy in Pediatric Bone Disorders.

PURPOSE OF REVIEW: Denosumab is an inhibitor of receptor activator of nuclear factor kappa-B ligand (RANKL), and has emerged as an important novel therapy for skeletal disorders. This article examines the use of denosumab in children. RECENT FINDINGS: Considerable safety and efficacy data exists for denosumab treatment of adults with osteoporosis, bone metastases, and giant cell tumors. Pediatric data is limited; however, evidence suggests denosumab may be beneficial in decreasing bone turnover, increasing bone density, and preventing growth of certain skeletal neoplasms in children. Denosumab's effect on bone turnover is rapidly reversible after drug discontinuation, representing a key difference from bisphosphonates. Rebound increased bone turnover has led to severe hypercalcemia in several pediatric patients. Denosumab is a promising therapy for pediatric skeletal disorders. At present, safety concerns related to rebounding bone turnover and mineral homeostasis impact use of denosumab in children. Research is needed to determine if and how these effects can be mitigated.

Surgical treatment for diffused-type giant cell tumor (pigmented villonodular synovitis) about the ankle joint.

BACKGROUND: Diffused-type giant cell tumor(Dt-GCT) is a rare, aggressive disorder of the joint synovium, bursa and tendon sheaths. Osseous erosions and subchondral cysts may develop as the result of synovium infiltration in Dt-GCT. We present a retrospective study of a series of patients who are diagnosed with Dt-GCT about the ankle joint, there clinical outcome is evaluated in this study. MATERIAL AND METHOD: Fifteen patients with radiologically and histologically confirmed Dt-GCT about the ankle joint were identified in our foot and ankle department. Patients were managed with open synovectomy for the tumor tissue and bone grafting for bony erosions. X-rays and MRI scans were used for evaluation of the tumor and bony erosions pre- and post-operatively. Pre- and post-operative ankle function was assessed using the American Orthopedic Foot and Ankle Society -Ankle and Hindfoot (AOFAS-AH) score and the Muscularskeletal Tumor Society (MSTS) score. RESULTS: The mean follow-up duration was 37.4 months (range 25 to 50 months). There were 6 males and 9 females, with a mean age of 35 years old (range 18 to 65 years). All patients had talar erosion with the average size of 10.1*9.1*8.2 mm, distal tibia was affected in 5 patients with the average size of 6.2*5.6*5.8 mm. 7 patients had tendon involvement, 2 patients had recurrence and progression of ankle osteoarthritis. Both of them underwent ankle fusion. At the time of last follow-up, the mean AOFAS-AH score increased from 49 to 80 points (p < 0.05), the MSTS score increased from 12 to 22 points (p < 0.05). CONCLUSION: For Dt-GCT with bony erosions, open synovectomy combined with bone grafting seems to be a safe and effective operation for the salvage of ankle joint. Fusion is recommended for failed and severe cartilage destruction of the ankle joint.

[Benign tumours and tumour-like lesions of the bone : General treatment principles]. / Benigne Tumoren und tumorähnliche Läsionen des Knochens : Allgemeine Behandlungsprinzipien.

BACKGROUND: Benign bone lesions are much more common than malignant lesions. Some benign bone tumors have a characteristic and typical radiographic appearance, while others are more challenging. Therapy of benign bone tumors differs greatly. While the majority of benign bone tumors do not require surgical therapy, other specific lesions, e. g. aneurysmal bone cysts or giant cell tumors (GCT) of the bone require surgery due to their locally aggressive behavior. DIAGNOSTICS: The major challenge for the radiologist and/or pathologist is the differentiation between a benign and low-grade malignant lesion (e. g. enchondroma versus low-grade chondrosarcoma) for which all available clinical and radiographic information is mandatory. Therefore, surgical therapy is rather more often performed than necessary due to uncertainty in many cases. THERAPY: Novel systemic therapies are available for fibrous dysplasia and GCT of the bone: Fibrous dysplasia can be treated with bisphosphonates, and GCT responds to denosumab. In fact, denosumab has been approved for the treatment of irresectable GCT. Osteoid osteoma is fairly easy to recognize and also to treat given the characteristic clinical presentation and rapid and effective response to local therapy (possible as percutaneous thermo-/laser ablation). In summary, several therapeutic options exist for benign bone tumors, and the choice depends upon the tendency/risk of local recurrence, the rate of surgical complications, options for defect reconstruction, postoperative functional deficits, and specific patient characteristics.

[Tumor-like lesions of bone]. / Tumorähnliche Knochenläsionen.

Historically, tumor-like lesions of bone were defined as non-neoplastic bone lesions. Today, however, some of them are considered real neoplasms. They are among the most frequent bone lesions. They usually grow slowly, but occasionally they grow rapidly. Many of them can be diagnosed by plain films alone; in others, CT and MRI yield additional features for a correct diagnosis. Some lesions do not need treatment; others should be resected, and some may even recur. Non-ossifying fibroma, juvenile and aneurysmal bone cysts, fibrous and osteofibrous dysplasia and eosinophilic granuloma are presented.

Curettage with cement augmentation of large bone defects in giant cell tumors with pathological fractures in lower-extremity long bones.

BACKGROUND: Thorough curettage and cement augmentation is the procedure of choice for treating giant cell tumor lesions, particularly those associated with large defects. Its association with pathological fractures has not been studied to a great extent, although a pathological fracture following a giant cell tumor is not a contraindication to treatment by curettage and cementation. We present our experience of bone cementation following intralesional curettage for treatment of giant cell tumors of the long bones of lower limbs with associated pathological fractures. MATERIALS AND METHODS: A total of 38 patients who had undergone a procedure in the weight-bearing long bones of lower limbs were included in the study. The age of the patients ranged from 18-79 years with a mean age of 38.57 years. The average follow-up was 102.42 months (8.5 years) ranging from 60-186 months (5-15.5 years). Results were based on serial radiographs showing consolidation of the lesion along with a subjective clinical examination and Enneking functional evaluation noted in the patient's records. RESULTS: Approximately 76 % of the lesions occurred around the knee. The results were graded as excellent (72 %), good (12.82 %) fair (10.25 %) and poor (5.12 %). Four cases developed a recurrence. Apart from a few documented complications, the lesions showed good consolidation and healed well. CONCLUSION: Giant cell tumors of the long bones of lower limbs with an associated pathological fracture at diagnosis can be managed with thorough curettage and cement augmentation of the bone defect with a satisfactory outcome. LEVEL OF EVIDENCE: Level IV.

A Case Report of Diffuse-type Tenosynovial Giant Cell Tumor as a Calcaneus Mass: A Diagnostic Challenge.

INTRODUCTION: Diffuse-type tenosynovial giant cell tumor (D-TGCT) originates from synovial cells in tendon sheaths and bursae and rarely presents as a calcaneal mass. CASE REPORT: A 44-year-old female presented with left heel pain that had persisted for over a year and had worsened over the past six months. A mass was found on the Lateral radiograph of the calcaneus, which was diagnosed as an aneurysmal bone cyst. Non-contrast computed tomography (CT) and magnetic resonance imaging (MRI)diagnosed a benign tumor. Based on light microscopy, special stains, and immunohistochemistry, a final diagnosis of diffuse tenosynovial giant cell tumor (D-TGCT) was rendered. RESULTS: D-TGCT is a slow-growing, infiltrative tumor that can form single or multiple masses outside the joint, and can also involve adjacent jointsmainly affects weight-bearing joints such as the knee, hip, and ankle. However, D-TGCT presents as a calcaneal mass, which poses a diagnostic challenge for all radiologists. CONCLUSION: A calcaneal mass exhibiting well-defined borders, focal cortical destruction, a sclerotic rim, and T2WI hypointensity, the possibility of D-TGCT should be considered.

Unusual Multiple Recurrences of Soft Tissue Giant Cell Tumors in a Patient Above 60 Years.

Primary giant cell tumors of soft tissues (GCT-ST) are rare neoplasms that share histopathological and immunohistochemical characteristics with osseous giant cell tumors. While GCT-ST generally exhibits a benign progression and can affect individuals of various ages, older patients may face a higher risk of recurrence and aggressive disease progression. In this case report, we present the case of a 63-year-old woman who experienced recurrent GCT-ST nine months after the complete excision of an initially localized tumor. Despite the mainstay treatment of GCT-ST being tumor-free margin surgical excision, this case demonstrates the occurrence of recurrences. The etiology of recurrence in GCT-ST remains unclear, highlighting the need for further studies and careful patient follow-up to prevent potential complications such as lung metastasis or widespread metastasis. Thus, this report aims to raise awareness of these tumors and emphasize the importance of diligent patient follow-up to facilitate early identification and management, thereby preventing potential complications such as lung or widespread metastasis.

Integrating coaxial electrospinning and 3D printing technologies for the development of biphasic porous scaffolds enabling spatiotemporal control in tumor ablation and osteochondral regeneration.

The osteochondral defects (OCDs) resulting from the treatment of giant cell tumors of bone (GCTB) often present two challenges for clinicians: tumor residue leading to local recurrence and non-healing of OCDs. Therefore, this study focuses on developing a double-layer PGPC-PGPH scaffold using shell-core structure nanofibers to achieve "spatiotemporal control" for treating OCDs caused by GCTB. It addresses two key challenges: eliminating tumor residue after local excision and stimulating osteochondral regeneration in non-healing OCD cases. With a shell layer of protoporphyrin IX (PpIX)/gelatin (GT) and inner cores containing chondroitin sulfate (CS)/poly(lactic-co-glycolic acid) (PLGA) or hydroxyapatite (HA)/PLGA, coaxial electrospinning technology was used to create shell-core structured PpIX/GT-CS/PLGA and PpIX/GT-HA/PLGA nanofibers. These nanofibers were shattered into nano-scaled short fibers, and then combined with polyethylene oxide and hyaluronan to formulate distinct 3D printing inks. The upper layer consists of PpIX/GT-CS/PLGA ink, and the lower layer is made from PpIX/GT-HA/PLGA ink, allowing for the creation of a double-layer PGPC-PGPH scaffold using 3D printing technique. After GCTB lesion removal, the PGPC-PGPH scaffold is surgically implanted into the OCDs. The sonosensitizer PpIX in the shell layer undergoes sonodynamic therapy to selectively damage GCTB tissue, effectively eradicating residual tumors. Subsequently, the thermal effect of sonodynamic therapy accelerates the shell degradation and release of CS and HA within the core layer, promoting stem cell differentiation into cartilage and bone tissues at the OCD site in the correct anatomical position. This innovative scaffold provides temporal control for anti-tumor treatment followed by tissue repair and spatial control for precise osteochondral regeneration.

The effect of preoperative embolization on giant cell tumors of the bone localized in the iliosacral region of the pelvis.

INTRODUCTION: Giant cell tumors of the bone (GCTB) are aggressive neoplasms, with rare occurrences in the posterior pelvis and sacral area. Surgical challenges in this region include the inability to apply a tourniquet and limited cementation post-curettage due to proximity to neurovascular structures, leading to potential complications. This case-control study explores the impact of preoperative embolization on GCTB located in the iliosacral region. METHODS: Five surgeries (January-December 2021) for pelvic GCTB (3 sacrum, 2 posterior ilium) were performed on four patients. Diagnosis was confirmed through preoperative CT-guided biopsies. One surgery involved curettage with PMMA cement filling, while four surgeries had curettage without cavity filling. Preoperative embolization of the tumor feeding vessel occurred approximately 16 h before surgery in two cases. Denosumab treatment was not administered. RESULTS: Tumor volume, assessed by preoperative MRI, was comparable between patients with and without preoperative embolization (p = .14). Surgeries without embolization had a mean intraoperative blood loss of 3250 ml, erythrocyte transfusion volume of 1125 ml, and a mean surgical time of 114.5 min for two surgeries. Surgeries with preoperative embolization showed a mean intraoperative blood loss of 1850 ml, no erythrocyte transfusion requirement, and a mean surgical time of 68 min. CONCLUSION: Curettage of GCTB in the posterior pelvis and sacrum presents challenges, with significant intraoperative blood loss impacting surgical time and transfusion needs. Preoperative embolization may be beneficial in reducing blood loss during surgery in these cases.