Adamantinoma of the Ulnar Shaft Reconstructed With a Vascularized Free Fibula.

We describe a 36-year-old man with a long-standing diagnosis of ulnar fibrous dysplasia with associated fracture of the ulna. He presented with a growing and increasingly tender forearm mass and was diagnosed with adamantinoma of the ulna, for which he underwent wide resection of the ulnar diaphysis followed by reconstruction with a vascularized fibula autograft. This case serves to emphasize the importance of performing a stepwise workup for the diagnosis of osseous neoplasms even in cases with long-standing diagnoses. [Orthopedics. 2024;47(2):e102-e105.].

Adamantinoma-Like Ewing Sarcoma of the Mandible Evaluated on 18F-FDG PET/CT.

ABSTRACT: Ewing sarcoma is the second most common primary bone tumor in children. Typical Ewing sarcoma most frequently occurs in long bones and within the pelvis. ALES (adamantinoma-like Ewing sarcoma) is a rare subtype of Ewing sarcoma that is characterized by epithelial differentiation in addition to small round blue cells. Unlike typical Ewing sarcoma, ALES has been described in several cases in the head and neck. Herein, we describe a case of a 9-year-old boy with ALES of the mandible evaluated on 18F-FDG PET/CT with correlative MRI scans.

A unique case of adamantinoma-like Ewing sarcoma in the calcaneus, exhibiting prominent squamous differentiation and displaying EWSR1 gene rearrangement.

Adamantinoma-like Ewing sarcoma is uncommonly reported in the skeletal sites, including small bones of the feet.A 15-year-old girl presented with pain and swelling in her left foot, leading to difficulty in walking for 8 months. Plain radiograph revealed an ill-defined, lytic-sclerotic lesion without significant periosteal reaction in her left calcaneus. Magnetic resonance imaging (MRI) revealed an expansile lesion involving the anterior calcaneus, which was hypointense on T1 and heterogeneously hyperintense on T2-weighted sequences, infiltrating the adjacent bones and soft tissues. On imaging, the differential diagnoses considered were a giant cell tumor and other primary bone tumors.Histopathological examination revealed a tumor composed of small round cells, with interspersed keratin pearls. Immunohistochemically, the tumor cells were positive for CD99/MIC2, pan-cytokeratin (AE1/AE3), p40, p63, NKX2.2, and synaptophysin. Diagnosis of adamantinoma-like Ewing sarcoma was offered on the initial biopsy. Furthermore, the tumor cells revealed EWSR1 gene rearrangement by fluorescence in situ hybridization, confirming this diagnosis. The patient underwent neoadjuvant chemotherapy, had a poor response, and finally underwent below-knee amputation.This constitutes a rare case of adamantinoma-like Ewing sarcoma in the calcaneus. Ewing sarcoma may be considered as a differential diagnosis for intraosseous lytic-sclerotic lesions, even without significant periosteal reaction, at unusual sites, such as the bones of the foot. Awareness of this entity and application of ancillary techniques is recommended for its exact diagnosis and in differentiating this rare variant from its diagnostic mimics. This case also indicates a poor chemotherapy response in this unusual variant of Ewing sarcoma, occurring in the calcaneus.

Adamantinoma: An Updated Review.

Adamantinoma is a biphasic tumor, with a low potential for malignancy, characterized by clusters of epithelial cells surrounded by a relatively bland spindle-cell osteofibrous component. The aim of the present study was to review the updated data regarding epidemiology; pathogenesis; clinical presentation; radiological, histopathological and ultrastructural findings; and treatment options of adamantinoma. In X-ray, it is usually seen as an eccentric and sometimes central, lobular, lytic lesion with sclerotic margins of overlapping radiolucency, and a characteristic 'soap-bubble' appearance. Magnetic resonance imaging seems to be the most appropriate examination for differential diagnosis between adamantinoma and other skeletal tumors. Histologically, adamantinoma is identified as classic adamantinoma or osteofibrous-like adamantinoma. Classic adamantinoma is classified into four patterns of growth: Basaloid, tubular, spindle cell, and squamous. The preferable treatment of this tumor type is en bloc resection within wide operative margins, which may include suspicious regional lymph nodes, with limb reconstruction and limb salvage.

Skeletal EWSR1-NFATC2 sarcoma previously diagnosed as Ewing-like adamantinoma: A case report and literature review emphasizing its unique radiological features.

Ewing-like adamantinoma (EAD) is a rare bone tumor. It remains unclear whether EAD belongs to adamantinoma, Ewing sarcoma (ES), or an independent category. Herein, we present a case of femoral sarcoma previously diagnosed as EAD in a 26-year-old woman. We observed amplified EWSR1 and NFATC2 fusion signals using fluorescence in situ hybridization. Prompted by its unique radiological features, we reviewed the current literature on skeletal EWSR1-NFATC2 sarcoma (ENS) and EAD. In addition to the similar histological features, we found that both ENS and EAD displayed similar characteristic radiological features, such as the tendency to occur in the diaphysis of long bones, cortical expansion and buttressing-type thickening, and bone surface involvement with saucer-like erosion without cortical destruction. We believe that these unique radiological features were related to its indolent behavior. Altogether, it is possible that previously reported EAD cases may be neither ES nor the classic adamantinoma but ENS. Further studies are needed to clarify the relationship between EAD and ENS.

Adamantinoma: metastatic disease masquerading as a gynaecological malignancy.

Adamantinoma is a rare low-grade malignancy of the appendicular skeleton with unclear histogenesis. We present the case of a 65-year-old woman with known recurrent and metastatic right tibial disease despite clear resection margins. On further investigation, a positron emission tomography-CT scan identified a primary breast lesion and an 11 cm mass in the right iliac fossa of suspected ovarian malignancy amenable to surgical resection. The patient underwent total abdominal hysterectomy, bilateral salpingo-oophorectomy and resection of a retroperitoneal mass arising from the pelvic sidewall encompassing the iliac vasculature. The patient made an uneventful recovery with histology confirming disease metastasising to the pelvis. Currently, clinical management guidelines are not available. We present an overview of adamantinoma and highlight a previously undocumented gynaecological oncology surgical approach to this novel disease location. Regarding metastases, we acknowledge the challenges of investigation pertaining to disease site and origin as well as a paucity of recommendations for surveillance and follow-up.

Metastatic Adamantinoma of the Femur on FDG PET/CT: Atypical Presentation of a Rare Disease.

ABSTRACT: Adamantinomas are rare malignant primary bone tumors, which typically arise in young patients, are generally low-grade tumors, and classically arise from the anterior tibial diaphysis. We present the case of a 70-year-old woman who underwent repeat imaging with FDG PET for a pathologically proven case of femoral adamantinoma who experienced a relatively rapid development of metastatic disease with an atypical distribution of lesions.

Understanding The Rare Bone Tumor "ADAMANTINOMA".

Adamantinoma is a rare neoplastic bone tumor that has the potential to metastasize. The classic presentation is in the tibial region however; cases involving other bones of the body have been noticed. The tumour is very likely to be mistaken for other bone diseases and therefore it is important to investigate and study about its nature and thus differentiate it from other differentials. Nevertheless, literature on the presentation, findings, investigations and treatment options of adamantinomas are limited. In this case series, we report four cases from a local hospital in Karachi who were diagnosed, treated and followed up for adamantinoma. Studies regarding the disease will help us understand more about its features.

Recurrent adamantinoma of the mandible.

Adamantinoma is an extremely rare tumour originating from bone that can be divided into classical and osteofibrous dysplasia (OFD)-like adamantinoma. This low-grade malignancy almost exclusively occurs in long bones, and only few cases of mandibular adamantinoma have been reported. Here, we report the case of a 30-year-old female with a 2-year history of right mandible tenderness. Radiological examinations showed a lytic lesion involving the right mandible without a well-defined margin. Biopsy confirmed the diagnosis of adamantinoma. She underwent a segmental mandibulectomy and reconstruction with a fibula flap. The definitive diagnosis was OFD-like adamantinoma. However, the tumour recurred after 5 years. The residual mandible and fibula flap were widely involved. A total mandibulectomy was performed. Five years later, there is no evidence of recurrence or metastasis. We recommend that adamantinoma be treated by radical resection with clear margins, and long-term surveillance is necessary due to the likely high local recurrence rate and the potential for late tumour metastasis.

Outcome of osteofibrous dysplasia-like versus classic adamantinoma of long bones: a single-institution experience.

BACKGROUND: The clinical and molecular characteristics of osteofibrous dysplasia (OFD)-like adamantinoma (AD) differ from those of classic AD. Most reports about OFD-like AD are case reports or small case series. More cases from different centers are still warranted. METHODS: The orthopedic oncology database of our institution was searched to identify patients with AD. The cases of OFD-like and classic AD of the long bones were retrospectively analyzed. Between December 1999 and August 2016, 23 patients were treated for AD, comprising seven with OFD-like AD and 16 with classic AD. The outcomes were compared between AD subtypes. RESULTS: In the OFD-like AD group, four lesions were treated with extensive curettage, while three were treated with wide resection. The median follow-up duration in the OFD-like AD group was 66 months (range 43-131 months). At the end of follow-up, there was only one case of local recurrence (LR) in the OFD-like AD group, giving a LR rate of 14.3% (1/7). No distant metastasis or progression to classic AD was detected in the OFD-like AD group. In the classic AD group, the treatments were below-the-knee amputation in one patient with extensive tibial and fibular lesions, curettage with a bone graft in one patient who was diagnosed with OFD based on a core needle biopsy, hemi-cortical excision and reconstruction in two patients, and segmental resection and reconstruction in 12 patients. At the end of follow-up, there were three cases of LR in the classic AD group, giving a LR rate of 18.8% (3/16); two patients developed lung metastasis after LR and died of the disease at 88 and 126 months after the first surgery in our hospital, respectively. The classic AD group had a metastatic rate of 12.5% (2/16), a final limb salvage rate of 75%, and estimated 5- and 10-year survival rates of 88.9% and 77.1%, respectively. CONCLUSIONS: OFD-like AD has a better outcome than classic AD. For OFD-like AD, extensive curettage is suggested if the tumor extent allows. For classic AD, aggressive resection with wide margins is essential to achieve local control. A long-term follow-up is necessary due to the possibility of late complications.

Adamantinomatous tumors: Long-term follow-up study of 20 patients treated at a single institution.

BACKGROUND AND OBJECTIVES: Adamantinomas are primary, low-grade malignant tumors of the bone that have metastatic potential to the lungs, lymph nodes, and other regions. The rarity of this disease and its nonspecific symptoms complicate diagnosis. MATERIALS AND METHODS: Records for 20 patients who underwent treatment for adamantinoma from 1975 to 2018 were reviewed for demographic, clinical, and pathological data, treatment details, postoperative complications, and outcomes. RESULTS: Patients presented at a median age of 22 years (1-79 years): 14 patients had a localized primary tumor, three presented with local recurrence, and three with metastatic disease. Median tumor size was 5.7 cm (0.5-15.5 cm). Wide excision was performed primarily in 15 cases; the remaining five patients underwent intralesional curettage. At a median follow-up of 7.3 years, 14 patients had no evidence of disease; two patients were alive with disease, and four patients died from the disease. Local recurrence and distant metastasis occurred at a median of 11.4 years (6 month-19 years) and 15.8 years (4 month-23 years) after diagnosis. CONCLUSIONS: Adequate histopathological diagnosis is crucial to avoid misdiagnosis of this rare tumor. Local and distant recuAbs_Para_meprrence can occur more than 20 years after the initial diagnosis. Life-long follow-up with clinical examination and imaging is required.

[Pediatric adamantinoma. Case report]. / Adamantinoma en pediatría. Presentación de caso.

Adamantinoma is a primary tumor of long bones, which affects mainly the shaft of the tibia, and is extremely rare in pediatrics. It frequently presents during the second decade of life, with a slight predominance in males. It is a low grade tumor, with local aggressiveness and low rate of metastasis and recurrence once it is completely removed. Its diagnosis is difficult, not only because it is a rare disease in children, but also because of the difficulty in the differential diagnosis with other benign lesions. We report the case of a 15-year-old patient with a painless swelling of the distal tibia, whose diagnosis was confirmed with the piece of amputation, as imaging features and both initial biopsies were not enough to achieve diagnosis. Though most of the literature consists of case reports, and very few in pediatric patients, they all agree on the difficulty in achieving the diagnosis of adamantinoma.

Primary pulmonary synovial sarcoma requiring differentiation from pulmonary metastasis of tibial adamantinoma: a case report.

BACKGROUND: Primary pulmonary synovial sarcoma (PPSS) is rare. We describe a case of PPSS complicated by tibial adamantinoma that required differentiation from lung metastasis. CASE PRESENTATION: A 39-year-old Japanese woman presented with hemoptysis, dyspnea, and a well-defined tumor measuring 3.0 cm in greatest diameter in the right lower lobe on chest computed tomography (CT). Positron emission tomography/CT with fluorodeoxyglucose (FDG-PET/CT) showed mild uptake of FDG (maximum standardized uptake value of 2.0). Her past history included surgery for adamantinoma of the right tibia at age 25 years. We considered the possibility of pulmonary metastasis from the adamantinoma and performed fluoroscopy-assisted thoracoscopic resection of the tumor after CT-guided Lipiodol marking. Histologically, the tumor was composed mainly of a dense proliferation of spindle cells. Immunohistochemical studies were positive for epithelial membrane antigen, B cell lymphoma 2, and transducing-like enhancer of split 1. They were negative for CD34. The synovial sarcoma, X breakpoint 1 gene-fusion transcript was detected by reverse transcription-polymerase chain reaction. It is diagnostic of PPSS. Resection margins were negative. The patient was well without evidence of recurrence or metastasis of the PPSS or adamantinoma at the 30-month and 15-year follow-ups. CONCLUSION: Clinical and radiological manifestations of PPSS overlap with those of other lung tumors. The solitary pulmonary nodule in this case was indistinguishable from pulmonary metastases of the adamantinoma based on clinical symptoms, epidemiology, chest radiography, CT, and FDG-PET/CT. PPSS was diagnosed only after evaluating gross pathology, histology, immunohistochemistry, and cytogenetics. PPSS should be included in the differential diagnosis of a well-defined homogeneous round or oval lung mass. To our knowledge, this is the first report of PPSS complicated by adamantinoma.

Computer-assisted surgery in orthopedic oncology.

BACKGROUND AND PURPOSE: In orthopedic oncology, computer-assisted surgery (CAS) can be considered an alternative to fluoroscopy and direct measurement for orientation, planning, and margin control. However, only small case series reporting specific applications have been published. We therefore describe possible applications of CAS and report preliminary results in 130 procedures. PATIENTS AND METHODS: We conducted a retrospective cohort study of all oncological CAS procedures in a single institution from November 2006 to March 2013. Mean follow-up time was 32 months. We categorized and analyzed 130 procedures for clinical parameters. The categories were image-based intralesional treatment, image-based resection, image-based resection and reconstruction, and imageless resection and reconstruction. RESULTS: Application to intralesional treatment showed 1 inadequate curettage and 1 (other) recurrence in 63 cases. Image-based resections in 42 cases showed 40 R0 margins; 16 in 17 pelvic resections. Image-based reconstruction facilitated graft creation with a mean reconstruction accuracy of 0.9 mm in one case. Imageless CAS was helpful in resection planning and length- and joint line reconstruction for tumor prostheses. INTERPRETATION: CAS is a promising new development. Preliminary results show a high number of R0 resections and low short-term recurrence rates for curettage.

Adamantinoma.

A 73-year-old woman with no significant past medical history presents with a palpable lump in the midshaft of the left tibia and intermittent mild discomfort for the past 8 months.