Treatment trends of benign bone lesions in a suburban New York healthcare system.

Introduction: The management of benign bone lesions is controversial as it is dependent on a multitude of factors such as age, anatomic location, comorbidities, lesion metabolic activity, surgeon preferences, and goals of care, among others. Thus far, many studies have attempted to report on these lesions; however, most are heterogeneous compilations of benign and malignant lesions with nearly all failing to report patient treatment and none of which have originated from a suburban area of the United States. The goal of this study was to establish a modern database dedicated solely to benign bone tumors to reflect current diagnosis and treatment trends in suburban New York. Materials and Methods: This was a multicenter retrospective observational study with inclusion criteria limited to benign bone lesions of all ages. Malignant lesions were excluded. Patients were drawn from both primary care provider and surgeon records, with documentation of their associated management. Results: A total of 689 patients met inclusion criteria. The overall operative rate for this cohort was 71.6%. In agreement with current literature, aneurysmal bone cysts, giant cell tumors, and osteochondromas underwent surgery more frequently than enchondromas; older patients underwent surgery less frequently; benign bone lesions were more commonly found in younger males, and the distal femur and proximal tibia were the most common locations for lesions (P < .05 for all findings). Conclusion: This study demonstrates the management of a globally representative variety of benign bone lesions in a diverse suburban population of New York and should facilitate future research on how lesion type, location, management, and other factors relate to patient outcomes.

Did COVID-19 related delays in surgical management lead to patient morbidity in the orthopaedic oncological population?

AIMS: The aim of this study was to assess orthopaedic oncologic patient morbidity resulting from COVID-19 related institutional delays and surgical shutdowns during the first wave of the pandemic in New York, USA. METHODS: A single-centre retrospective observational study was conducted of all orthopaedic oncologic patients undergoing surgical evaluation from March to June 2020. Patients were prioritized as level 0-IV, 0 being elective and IV being emergent. Only priority levels 0 to III were included. Delay duration was measured in days and resulting morbidities were categorized into seven groups: prolonged pain/disability; unplanned preoperative radiation and/or chemotherapy; local tumour progression; increased systemic disease; missed opportunity for surgery due to progression of disease/lost to follow up; delay in diagnosis; and no morbidity. RESULTS: Overall, 25 patients met inclusion criteria. There were eight benign tumours, seven metastatic, seven primary sarcomas, one multiple myeloma, and two patients without a biopsy proven diagnosis. There was no priority level 0, two priority level I, six priority level II, and 17 priority level III cases. The mean duration of delay for priority level I was 114 days (84 to 143), priority level II was 88 days (63 to 133), and priority level III was 77 days (35 to 269). Prolonged pain/disability and delay in diagnosis, affecting 52% and 40%,respectively, represented the two most frequent morbidities. Local tumour progression and increased systemic disease affected 32% and 24% respectively. No patients tested positive for COVID-19. CONCLUSION: COVID-19 related delays in surgical management led to major morbidity in this studied orthopaedic oncologic patient population. By understanding these morbidities through clearer hindsight, a thoughtful approach can be developed to balance the risk of COVID-19 exposure versus delay in treatment, ensuring optimal care for orthopedic oncologic patients as the pandemic continues with intermittent calls for halting surgery. Cite this article: Bone Jt Open 2021;2(4):236-242.

Outcomes of press-fit uncemented versus cemented hip arthroplasty in the oncologic patient.

BACKGROUND AND OBJECTIVES: Cemented hip arthroplasty is considered the standard of care for treating both osteoporotic femoral neck fractures and pathologic disease of the proximal femur due to the ability to achieve strong fixation in poor quality bone. There is minimal literature evaluating uncemented arthroplasty for pathologic disease of the proximal femur. This objective of this study is to compare outcomes of patients undergoing cemented and uncemented arthroplasty of the proximal femur for an oncologic indication. METHODS: Patients who underwent hip arthroplasty procedures in one health system for an oncologic indication were identified. Demographics, cancer history, operative history, and complications were collected retrospectively. Harris Hip Scores (HHS) and Musculoskeletal Tumor Society Scores (MSTS) were prospectively collected via telephone. RESULTS: 41 patients met criteria for review. 18 underwent cemented and 23 underwent uncemented arthroplasty. There were no significant differences in age, demographics, complications, 30-day mortality, intraoperative blood loss, transfusion requirements, average HHS, or average MSTS. CONCLUSION: No significant differences were found for patients undergoing hip arthroplasty for an oncologic indication regardless of whether or not the femoral component was cemented. Our results suggest that cemented and uncemented techniques are both safe and effective methods to be used at the oncologic surgeon's discretion.

Synovial Sarcoma Mimicking Pleomorphic Hyalinizing Angiectatic Tumor of Soft Parts: A Case Report.

Synovial sarcoma is a high-grade sarcoma commonly affecting young adults. The sites of involvement include soft tissue near joints, lung, pleura, mediastinum, larynx, kidney, and buttocks. Histologic types include monophasic, biphasic, and undifferentiated. We report a unique case of synovial sarcoma with low-grade histologic features mimicking pleomorphic hyalinizing angiectatic tumor (PHAT) with indolent behavior for a period of 10 years. The tumor showed angiectatic blood vessels with fibrinous cuffing, hypocellular and hypercellular spindle cell areas with rare mitoses, and focal atypia in a myxoid background. TLE1 was positive with SYT gene translocation detected on fluorescent in situ hybridization. Cases of myxoinflammatory fibroblastic sarcoma and myxofibrosarcoma have been reported as exhibiting histologic features of PHAT. However, to the best of our knowledge, cases of synovial sarcoma mimicking PHAT have not been reported.

Epiphyseal Primary Diffuse Large B-Cell Lymphoma of Bone.

Primary lymphoma of bone (PLB) confined to the epiphysis has only been described in four other patients. Due to the rarity of this entity, diagnosis has often been delayed, leading to mismanagement with adverse clinical consequences. We report a fifth case of primary epiphyseal lymphoma of bone located in the left distal medial femoral epiphysis of a 13-year-old boy. Radiographic and histologic features of PLB are discussed, along with a review of the literature and pitfalls of misdiagnosis. The patient initially presented with six months of progressive left knee pain with an associated loss of passive range of motion. Imaging revealed a mixed radiolucent lesion within the left distal medial femoral epiphysis with cortical breakthrough. A core biopsy was performed revealing a blue round cell tumor. Thanks to modern immunohistochemistry techniques, a diagnosis of primary lymphoma of bone was quickly made. The patient thus avoided further surgical intervention and received the appropriate treatment of chemotherapy, with subsequent rapid resolution of the lesion. This case highlights the necessity of including primary lymphoma of bone in all epiphyseal lesion differential diagnoses, especially in the pediatric patient population when aggressive radiographic features are present.

Osteogenic melanoma: report of a case mimicking osteosarcoma and review of the literature.

A 32-year-old male presented with a right thumb lesion of 11-month duration. A clinical diagnosis of pyogenic granuloma was entertained but the lesion failed to respond to conservative therapy and eventually necessitated amputation of his thumb. MRI of the right thumb showed an ill-defined, heterogeneously enhancing, infiltrating mass within the dorsal soft tissues abutting the distal phalanx and measuring 4.2 × 2.4 × 0.7 cm. Histologically, the tumor was composed of a high-grade osteosarcoma with a chondrosarcomatous component localized within the underlying bone and a more superficial spindle cell component in the overlying soft tissue. The epidermis was focally ulcerated overlying the lesion. The key to the diagnosis was provided by intense staining of the spindle cell component for S100 protein indicative of a spindle cell melanoma. The presence of an associated osteogenic sarcomatous component established a final diagnosis of osteogenic melanoma. The localization of this element to phalangeal bone is distinctly unusual and resulted in the close resemblance to a primary osteogenic sarcoma.

Extraskeletal osteosarcoma arising in myositis ossificans: a case report and review of the literature.

We report a case of a 23-year-old female with pain and fullness in the right popliteal fossa. An MRI scan demonstrated an ossified enhancing soft tissue mass. Evaluation of the resected specimen showed a high-grade extraskeletal osteosarcoma juxtaposed to the three zones of myositis ossificans. At 1-year follow-up the patient is alive and disease free. A review of the literature purporting to document such an association failed to demonstrate a single case in which an osteosarcoma and MO with its zonal architecture co-existed.

BCOR upregulation in a poorly differentiated synovial sarcoma with SS18L1-SSX1 fusion-A pathologic and molecular pitfall.

The diagnosis of poorly differentiated synovial sarcoma (PD-SS) may be challenging due to overlapping morphologic features with other undifferentiated round cell sarcomas (URCS). Particularly relevant is the histologic overlap and shared BCOR overexpression between a subset of SS and URCS with various BCOR genetic abnormalities. Here, we report a case of PD-SS lacking the canonical SS18-SSX gene fusion, but showing strong BCOR immunoreactivity and BCOR gene abnormalities by FISH, which were misinterpreted as a URCS with BCOR gene rearrangements. The tumor had an unusual clinical presentation arising as an intraneural tumor in the ankle of a 29-year-old female. The tumor displayed a mixture of fascicular spindle cells and undifferentiated round cell components. FISH studies showed no SS18 gene abnormality; however, RNA sequencing identified a fusion transcript involving SS18L1 (a paralog gene of SS18 at 20q13.33) and SSX1. Further FISH testing validated rearrangements in SSX1 and SS18L1 genes, in addition to complex structural abnormalities of the Xp11.22-4 region. This is the second reported SS case harboring an SS18L1-SSX1 alternative fusion variant, similarly occurring in association with a large nerve. The lack of SS18 gene rearrangements by FISH corroborated with the BCOR overexpression at both mRNA and protein level may result in diagnostic pitfalls with URCS with BCOR gene abnormalities. Our results further suggest that BCOR upregulation is emerging as a common downstream pathway for SS with either typical SS18-SSX transcript or with rare fusion variants, such as SS18L1-SSX. © 2017 Wiley Periodicals, Inc.

Subcutaneous extraskeletal osteosarcoma of the forearm: a case report and review of the literature.

Extraskeletal osteosarcoma (ESOS) originating in the subcutaneous tissue is a rare occurrence, accounting for less than 10 % of ESOS cases. Osteosarcoma of extraskeletal origin accounts for approximately 2-4 % of all osteosarcomas, and 1 % of soft tissue sarcomas. We report a case of an 80-year-old female with an isolated primary subcutaneous tumor of the forearm. After imaging, surgical excision, and pathological analysis, the diagnosis of a subcutaneous osteosarcoma was made. This report documents the clinical and pathological findings of subcutaneous ESOS in this case, along with a review of previous cases of subcutaneous ESOS.

A rare case of pseudotumor formation associated with methyl methacrylate hypersensitivity in a patient following cemented total knee arthroplasty.

Hypersensitivity to orthopedic implant materials has been well documented with potential catastrophic consequences if not addressed pre-operatively. The spectrum of reactions is wide, from mild non-specific pain with localized erythema to severe periprosthetic inflammatory destruction and pseudotumor formation. It is therefore essential to identify patients who have or are at risk for implant-associated hypersensitivity. Although metal sensitivity is commonly cited as the cause of these reactions, methyl methacrylate (MMA) has rarely been implicated. To the best of our knowledge, methyl methacrylate-associated pseudotumor formation has not yet been described. The following is a case report of a 68-year-old female who, after undergoing a routine cemented right total knee arthroplasty, developed a painless, enlarging mass during a 13-year period. This mass was found to be a pseudotumor in association with methyl methacrylate hypersensitivity. A review of pseudotumor pathogenesis, methyl methacrylate hypersensitivity, and preoperative preventative care is discussed.

Primary perivascular epithelioid cell neoplasm (PEComa) of bone: report of two cases and review of the literature.

Primary perivascular epithelioid cell neoplasms (PEComas) of bone are rare mesenchymal tumors. Histologically, they are composed predominantly of perivascular epithelioid cells and have the capacity to metastasize. PEComas have been reported within intra-abdominal and intra-pelvic organs. To the best of our knowledge, only seven primary PEComas of bone have been described in the English literature. We present two cases of PEComa of bone, one arising from the distal fibula and one from the acetabulum. Both were treated by surgical excision and one also received adjuvant chemotherapy.

Total condylar unipolar expandable prosthesis for proximal tibia malignant bone tumors in early childhood.

Wide resection and reconstruction of tumors of the proximal tibia in the pediatric population are challenging procedures. The use of hinged, expandable prostheses may cause early closure of the distal femoral growth plate, which may increase the risk of limb discrepancy already present in this population. Between 1991 and 2001, 2 girls and 1 boy, aged 6, 6, and 4 years, respectively, were diagnosed with osteosarcoma of the proximal tibia and treated with wide resection and reconstruction with a condylar unipolar expandable tibial prosthesis. A press-fitted technique was used for component insertion. All patients received neoadjuvant and adjuvant chemotherapy. Radiographic and functional follow-up took place at least once a year for a minimum of 4 years. Adequate pain control, limb-length equality, and acceptable function were obtained in all patients. One patient presented with significant range of motion reduction (0°- 30°) in the affected knee. Limb lengthening was performed as needed to maintain balanced limb length. All patients had a good Musculoskeletal Tumor Society category score. No complications occurred in terms of component loosening or infection. One patient died shortly after 4-year follow-up because of doxorubicin-induced leukemia. Currently used hinged, expandable prostheses can jeopardize the unaffected distal femoral growth plate. This article describes a technique of reconstruction that spares the distal femoral growth plate. Adequate limb length can be expected with acceptable functional outcome. However, it is imperative to keep in perspective the expectations of the physician, the physician's team, the patient, and the patient's family.

Chondrosarcoma of the femur with histology-imaging correlation of tumor growth--preliminary observations concerning periosteal new bone formation and soft tissue extension.

UNLABELLED: The objective of this study was, in chondrosarcoma (CHS) of the femur, to evaluate by radiologic-pathologic correlation, the degree of tumor growth, cortical destruction, periosteal reaction, and soft tissue extension present. MATERIALS AND METHODS: Eight cases of histologically proven CHS of the femur were studied. All cases were resected, evaluated histologically with coronal slabs, and compared with radiographs and magnetic resonance imaging (MRI) scans. In two resected specimens, the tumors were studied in more detail; along with coronal slabs, axial sections of the remaining anterior and posterior halves of both tumors were taken, and the bone specimens were X-rayed and examined histologically. RESULTS: CHS initially involved the medullary cavity and subsequently destroyed the cortex; first, by endosteal scalloping and, second, by subsequent invasion and destruction of the cortex. During this process, there was periosteal new bone formation (PNBF), with increased cortical thickness, the degree of which often correlated with the degree of cortical destruction. In the areas of cortical thickening of three cases, a "grey line" was seen on MRI that separated the cortex from the periosteal new bone; the line, in reality,is a space between the two structures. The presence of this line suggests that the tumor does not extend beyond the cortex. PNBF occurred in all cases and varied in thickness. It frequently developed independent of direct periosteal tumor involvement. The periosteum of one case contained porotic bone with interposed marrow fat, which was easily misinterpreted as tumor extension on MRI. Expansion and remodeling of the femoral diaphysis in CHS, with widening of the medullary cavity, is usually due to extensive cortical destruction with PNBF. Soft tissue extension was present in five cases and apparently occurred by two different mechanisms: direct tumor destruction of the cortex and periosteum, with extension into the soft tissues; and subtle MRI occult tumor permeation through the periosteum. As far as we know, a first literature histologic description of the thickened CHS periosteum also was accomplished. CONCLUSION: PNBF is a common imaging manifestation of CHS of the femur, which correlated with the degree of cortical destruction. A grey line between the cortex and periosteum is an MRI finding described in this study and may facilitate the evaluation of periosteal thickening and tumor invasion in CHS. PNBF often occurs in the absence of direct periosteal involvement. Periosteal imaging abnormalities suggestive of tumor infiltration should be interpreted with caution on MRI, and early soft tissue extension in CHS may be difficult to determine on MRI.

Metastatic lesions of the proximal femur.

Skeletal metastases are common in the adult population. The proximal femur is a frequently affected bone in the appendicular skeleton. The orthopaedic surgeon may be the first to find a pathologic lesion of the proximal femur and appropriate diagnosis and nonoperative management is essential prior to surgical treatment. Bisphosphonates and radiation therapy are used in conjunction with surgical management to minimize pain and prevent further destruction. Surgical management may consist of internal fixation, with or without polymethylmethacrylate, or endoprosthesic replacement. The goal of treatment is to relieve pain and allow for function while minimizing systemic complications.

Digital intraosseous epidermoid inclusion cyst of the distal phalanx.

Epidermoid inclusion cysts (EIC) of the bone are exceedingly rare. We present a case of an atypical EIC originating at the base of the distal phalanx of the index finger following a remote history of crush injury to the finger. The differential diagnosis of expansile, lytic lesions of the phalanges remains broad, and definitive diagnosis requires tissue histopathological analysis. At latest follow-up, the patient was pain-free and obtained an excellent clinical and radiographic outcome following intra-lesional curettage and bone grafting. Differentiation of EIC from other radiolucent digital lesions remains challenging, especially when classic radiographic findings are not seen. We review the clinical, radiographic, and pathologic diagnostic features of this lesion, as well as our current treatment algorithm.

Conventional intramedullary chondrosarcoma with subarticular involvement.

A 78-year-old female patient with a lesion in the distal tibia is shown to have conventional intramedullary chondrosarcoma. Typical considerations for this end-of-bone neoplastic lesion are giant cell tumor, clear cell chondrosarcoma, and chondroblastoma. Salient clinical and radiographic features and behavior of this lesion broaden the typical view of conventional intramedullary chondrosarcoma.

Cortico-medullary continuity in bizarre parosteal osteochondromatous proliferation mimicking osteochondroma on imaging.

Bizarre parosteal osteochondromatous proliferation (BPOP), or Nora's lesion, is an unusual surface-based lesion of bone found most commonly in the hands and feet. In the original description of the lesion and in all publications that followed, one of the key imaging characteristics used to define this entity was the lack of cortico-medullary continuity with the underlying bone. The authors present 4 unique cases of pathologically proven BPOP in which cortico-medullary continuity with the underlying bone was demonstrated on imaging. It is believed that florid reactive periostitis, BPOP and turret osteochondroma may reflect points along the same continuum with trauma the likely inciting event. The authors suggest that, given this continuum, it may be possible to have BPOP lesions demonstrating overlapping imaging features with osteochondroma. If this is the case, strict adherence to the standard imaging criterion of lack of continuity between the lesion and the underlying bone may lead to misdiagnosis of these unusual cases of BPOP as osteochondromas.

Dedifferentiated high-grade osteosarcoma originating from low-grade central osteosarcoma of the fibula.

Low grade central osteosarcoma is a distinct, rare low grade malignant neoplasm characterized histologically by a spindle cell proliferation associated with trabecular bone formation. This tumor usually carries a good prognosis. However, it has the potential to recur, dedifferentiate, and metastasize subsequent to surgical treatment. In extremely rare occasions, LGCOS presents with areas of dedifferentiation upon initial patient evaluation. In this report we describe one such case affecting the fibula of a 39-year-old female, presenting with pain. Initial biopsy demonstrated a high-grade osteosarcoma. No areas of LGCOS were seen histologically. Following biopsy the patient received 3 months of chemotherapy at a different institution. However, the patient continued to exhibit symptoms. X-rays indicated a very aggressive tumor in the diaphysis of the proximal fibula, MRI revealed soft tissue involvement. The tumor and surrounding soft-tissues were excised en bloc at our institution. Microscopically, the lesion consisted of high-grade osteosarcoma as well as an underlying LGCOS that involved the cortex and medullary cavity of the fibula. The two histological components of the tumor were sharply delineated from one another. No chemotherapy effect was appreciated histologically or clinically. Eight months following the surgery, the patient died from lung metastases. This is the third documented case of dedifferentiated LGCOS at initial presentation. This case reveals that the low-grade component was also evident on preoperative radiographs.

Epidermal inclusion cyst of phalanx: a case report and review of the literature.

Epidermal cyst within a toe phalanx is an extremely rare condition. It is important to differentiate this benign lesion, which can be easily treated by curettage, from other benign and malignant lesions of the bone with a similar clinical presentation, and which may require amputation of the toe. This report describes one such lesion in the mid-phalanx of the fourth toe in a 48-year-old woman, and which was successfully identified by intra-operative frozen diagnosis and treated by curettage.