Hemophilic pseudotumor of the knee joint: Emphasizing prevention and early diagnosis in a rare disease.

Key Clinical Message: Hemophilic pseudotumors are rare complications occurring in individuals with severe hemophilia, characterized by progressive cystic swellings in muscles and/or bones due to recurrent bleeding. Timely initiation of factor VIII replacement is crucial. Abstract: Hemophilic pseudotumors are rare complications occurring in individuals with severe hemophilia, characterized by progressive cystic swellings in muscles and/or bones due to recurrent bleeding. Although their incidence has decreased with the advent of factor VIII replacement therapy, they still create challenges, particularly in regions with limited access to medical care. Here, we present a case report of a hemophilic pseudotumor of the knee joint in a 15-year-old male with hemophilia A. The patient presented with severe left knee pain, swelling, and restricted range of motion, prompting further investigation. Imaging studies revealed lytic lesions, and MRI bone signal changes consistent with hemophilic pseudotumors. Prompt initiation of factor VIII replacement therapy and supportive management led to a significant improvement in symptoms and joint functionality. Follow-up after 2 months showed that the swelling had significantly reduced in size, with marked improvement in the functionality of the knee joint. This case confirms what is already known in the hemophilia literature: how important it is to prevent, diagnose, and treat pseudotumors early in hemophilia. However, longer clinical and imaging follow-up of this case is necessary to determine whether the complaints associated with pseudotumors resolve with hematologic treatment or will require surgical treatment.

Osteosarcoma in a Teenage Athlete With a Swollen Knee Joint.

Osteosarcoma is a malignant mesenchymal tumour. This primarily manifests in the formation of immature osteoid cells by tumour cells. Osteosarcoma is the most common primary bone tumour in children and adolescents. It tends to occur in the metaphysis of long shafts, shows osteoblastic differentiation, and produces malignant osteoid material. We present the case of a 17-year-old male who presented to our clinic who had left knee pain for a few days. An initial radiograph of the knee joint revealed a lytic lesion in the proximal tibia and further imaging was advised. During a follow-up visit, the patient had worsening pain and had a computerized tomography scan of the left knee, confirming osteosarcoma on the lateral side of the left tibia. He was referred to the orthopaedic department, where a biopsy was performed, to confirm the diagnosis of osteosarcoma. The patient was commenced on chemotherapy due to metastatic disease and has so far tolerated therapy well.

Isolated calvarial aneurysmal bone cyst in a pediatric patient: illustrative case.

BACKGROUND: Aneurysmal bone cysts (ABCs) are benign, osteolytic lesions that can occur in long bones, vertebrae, or rarely, the skull. Here the authors present the case of a 15-year-old male with a primary ABC of the left frontoparietal skull along with a review of the literature to provide insight into the nature of this rare disease. OBSERVATIONS: An otherwise healthy 15-year-old male presented with a tense, painful lesion of the left frontoparietal scalp. He could not identify any inciting trauma, but first noted the lesion less than 2 weeks prior to presentation with progressive enlargement. Cranial imaging revealed a lytic skull lesion with fluid-fluid levels suggestive of ABC. Curative therapy was provided via wide excision of the lesion and calvarial reconstruction of the resultant skull defect. This was performed without complication, and histopathological evaluation confirmed the diagnosis of primary ABC. LESSONS: ABCs of the skull are rare entities and most often arise in the skull base versus the calvaria. Typically, these lesions are associated with an underlying bone pathology (secondary ABCs) but can be rarely seen as isolated lesions (primary ABCs). Clinical management consists of excision and adjuvant therapy for underlying pathology where appropriate.

Unifocal Tubercular Osteomyelitis of Ulna Diaphysis in a Child: A Case Report.

Introduction: Osteoarticular tuberculosis (OATB) contributes to around 10% of extrapulmonary tuberculosis of which the spine is the most common site. Isolated involvement of ulna diaphysis is extremely rare. We present a case of unifocal tuberculous osteomyelitis of ulna diaphysis in a 3 -year-old male child and highlight its resemblance with musculoskeletal tumors and stress the importance of GeneXpert mycobacterium tuberculosis (MTB)/resistance to rifampicin (RIF) in the diagnosis of OATB. Case Report: A mother of a 2-year-old male child incidentally noticed that her son complained of left forearm pain. She was not sure of any fall or trauma to the forearm. No history of fever or other constitutional symptoms was present. Clinical examination was uneventful except for local tenderness in over the dorsomedial aspect of the left mid forearm. A plain radiograph revealed an oval solitary lytic lesion over distal one-third ulna diaphysis. A needle biopsy was done after clinical, hematological, and radiological evaluation, and finally, GeneXpert detected tuberculosis without RIF. No further tests were required and the child was started on antitubercular therapy (ATT) which resulted in complete healing without any symptoms. Conclusion: The authors conclude that it is therefore essential to consider tuberculosis in the differential diagnosis while evaluating a lytic bone lesion. Where possible, all patients should have a biopsy of the lesion and provide a specimen for GeneXpert MTB/RIF to confirm the diagnosis and drug susceptibility testing.

Primary Bone Lymphoma Masquerading as Multiple Myeloma: Challenges in the Diagnostic Workup of Severe Hypercalcemia.

In this case, we explore the diagnostic workup of a patient presenting with symptomatic hypercalcemia. Initially suspected to have multiple myeloma, the diagnostic evaluation instead unveiled non-germinal center (non-GC) diffuse large B-cell lymphoma (DLBCL). DLBCL is the most common histologic subtype of non-Hodgkin lymphoma and is heterogeneous in terms of presentation, genetic drivers, and morphology. As primary bone DLBCL is exceedingly rare, the case presented proved to be a diagnostic challenge. The patient presented with one week of weakness, one to two days of nausea, and leg pain. On admission, hypercalcemia, renal failure, anemia, and lytic bone lesions were present and suggestive of multiple myeloma. However, serum protein electrophoresis and immunoglobulin levels did not fit the 2016 World Health Organization (WHO) diagnostic criteria for multiple myeloma. A negative bone marrow biopsy also argued against a diffuse plasma cell neoplasm. Finally, a biopsy from another bone lesion was diagnostic of DLBCL. This case discusses an unusual presentation of DLBCL.

Challenging Diagnosis of Lytic Bone Lesions Between Multiple Myeloma and Bone Metastasis of Primary Breast Cancer.

Lytic bone lesions include various differential diagnoses, such as bone metastasis of cancer, multiple myeloma, primary bone cancers, and infections. Here, we report a rare case of primary breast cancer complicated by lytic bone lesions mimicking bone metastasis, which was subsequently diagnosed as multiple myeloma. Despite the development of several imaging modalities, such as magnetic resonance imaging and positron emission tomography/computed tomography, diagnosing lytic bone lesions with either multiple myeloma or tumor metastasis is highly challenging. Urinalysis is a noninvasive diagnostic method that includes useful diagnostic information; thus, physicians should evaluate urine protein levels when lytic bone lesions are observed.

Multiple Myeloma and the Role of Bisphosphonates in Its Management.

An aberrant growth of plasma cells in the bone marrow characterizes the hematological neoplasm known as multiple myeloma, which is typically accompanied by increased bone pain and skeletal-related events such as pathological fractures and/or spinal cord compression. Changes in the bone marrow microenvironment brought on by increased osteoclastic activity and/or decreased osteoblastic activity as a result of myeloma bone disease have a detrimental effect on quality of life. Bone-modifying medications such as bisphosphonates or denosumab are used to treat myeloma bone disease. These substances can lessen bone pain and the chance of pathological fracture, but they do not stimulate the growth of new bone or heal already damaged bone. In order to conduct this study, we searched the PubMed, Google Scholar, and Cochrane databases for complete free papers published in English and studied people over the previous five years, starting in 2018. The search covered randomized clinical trials (RCT), observational studies, meta-analyses, systemic reviews, and conventional reviews. Twenty-five publications are picked after using quality evaluation techniques to determine the type of study. These papers' full-text articles are investigated, examined, and tallied. We spoke about the various treatments for bone damage in multiple myeloma. It was discovered that bisphosphonates lessen the frequency and severity of bone problems. However, we are unsure of their contribution to survival. Although these medicines enhance life quality, it is unknown if they also increase overall survival. The focus of this study is on several kinds of bone-modifying drugs, their processes of action, the point at which therapy is started, how long it lasts, and any possible mortality advantages.

Ollier Disease: A Case Report and Review of Treatment Options.

Ollier disease is a rare skeletal dysplasia characterized by the formation of multiple enchondromas (enchondromatosis), typically in the long bones of the extremities. These tumors are benign but can become complicated by the development of pathologic fractures, limb deformity, and malignant transformation to chondrosarcoma. Ollier disease has a highly variable presentation and is associated with a range of presenting findings; however, the most common presentation is a pathologic fracture. Surgical options include curettage and grafting of the enchondromas and, when displaced, fracture reduction and fixation. Of note, these fractures will heal without surgery. Regardless, all patients must be routinely monitored with yearly radiographs in order to detect malignant transformation as early as possible.  In this report, we describe the case of an 11-year-old female who presented to her physician with pain and swelling of her right ring and small fingers after playing in a swimming pool with no obvious mechanism of trauma. A routine, plain radiographic evaluation of her hand revealed the presence of multiple enchondromatosis. We hope to use this case to highlight the surgical management options for young patients with Ollier disease and discuss circumstances in which surgical management may not be indicated.

Posterior Mediastinal Hydatid Cyst with Spine and Chest Wall Involvement.

Hydatid cyst, which is caused by Echinococcus larvae, is a worldwide zoonotic disease which can affect virtually any organ in the body. Although the liver and lungs are the most commonly affected, it can occur in other parts of the body. Mediastinal hydatid cysts are incredibly rare, but imaging is crucial to diagnose and determine the extent of involvement and complications. In this article, we present a case of posterior Mediastinal hydatid cyst with adjacent chest wall and spinal involvement, diagnosed through chest CT and histopathology.

Anatomical Variant of Upper Humerus Notch in a Pediatric Case.

When a medical image is requested for a particular indication, and a bony lesion is seen in a child, it causes anxiety to caregivers, unnecessary imaging costs, and unneeded biopsy. We present a complicated course of a five-month-old child who initially presented to the emergency room for prolonged cough and underwent a chest x-ray demonstrating clear lungs; however, a right humerus lytic lesion was identified. The child underwent multiple diagnostic imaging work-ups, which revealed a normal bone variation. This case report will describe a benign upper humeral notch variant with the goal to familiarize radiologists and clinicians with this entity and encourage them to obtain contralateral view radiographs to confirm bilaterality, prevent unnecessary advanced imaging as well added cost and anxiety to the parents.

Bony Metastasis to the Radius as the Initial Presentation of a Lung Adenocarcinoma.

When considering tumors of the bone, metastatic disease from a distant primary is more common than primary tumors of the bone itself. The commonest sites to which skeletal metastasis occur are in the axial skeleton, and with regard to the appendicular skeleton, metastasis to the forearm bones is uncommon. Almost a third of patients who present with skeletal metastases do not have any evidence of their primary tumor at presentation. We report a case of a 68-year-old female diagnosed with lung adenocarcinoma after presenting with metastatic deposits involving the right radius as the first clinical manifestation of her disease. She presented initially complaining of painful swelling of her right forearm for a duration of one year. Imaging investigations of her right forearm showed an expansile mixed lytic and sclerotic lesion involving the full length of the right radius. A contrast-enhanced computed tomography scan of her chest to investigate the possible site of primary malignancy showed a peripherally located, well-defined, irregularly shaped mass lesion with enlarged mediastinal lymph nodes. A fluorodeoxyglucose positron emission tomography (FDG-PET) bone scan also noted oligometastatic disease in her right proximal humerus. She was started on palliative docetaxel for six cycles with palliative external beam radiotherapy. Although a variety of tumors metastasize to the bone, metastasis to the appendicular skeleton, and in particular the forearm bones, is a rare phenomenon that is poorly described in the existing literature. Skeletal metastasis may also be the primary presenting feature in a minority of cases. Lung cancer is among the more commonly associated primary sites, and further workup should include appropriate imaging to evaluate for a lung primary as well as an FDG-PET/CT or a bone scan to detect occult metastatic disease.

Isolated Hypoglossal Nerve Palsy Secondary to Oligosecretory Multiple Myeloma.

Isolated hypoglossal nerve (CN XII) palsy is rare. Neurological complications of multiple myeloma (MM) are quite common, most often due to hyperviscosity and paraprotein-related neuropathy. Direct compression of CN XII can be caused by plasmacytoma, yet direct invasion by MM is extremely rare. We are reporting a very unusual case of a 45-year-old man who presented with an isolated right CN XII palsy. The cause revealed by MRI is stenosis of the hypoglossal canal resulting from lytic bony erosion. Despite negative serum and urine protein electrophoresis tests, the final diagnosis of oligosecretory MM was confirmed by serum-free light chain test and bone marrow biopsy. The causes and diagnosis of isolated XII nerve palsy and oligosecretory MM are discussed.

Describing IgA Myeloma: An Immunophenotypic and Molecular Approach.

Plasma cell myeloma (PCM) is defined as a clonal disease of terminally differentiated plasma cells that secrete immunoglobulin. The biologic underpinnings of IgA-type multiple myeloma's (IgAMM) aggressive nature, including its increased morbidity and mortality, have not been elucidated. We describe the clinical, phenotypic, and cytogenetic characteristics of IgA-MM. Flow-cytometry analysis was performed to phenotype clonal plasma cell populations, and interface with fluorescent in situ hybridization (iFISH) to exploit cytogenetics to determine risk stratification; 68.1% of cases were of intermediate or high risk. On flow cytometry, samples from our IgA-PCM cohort revealed less frequent CD56 expression when compared to samples with other PCM subtypes. Our study demonstrated lower frequency of CD56 expression (52.8%). We hypothesize that loss of CD56 may play a significant role in the aggressive behavior of IgA-PCM due to the loss of cell-to-cell adhesion resulting in a higher propensity for extramedullary presentation.

Amyloidosis of the Femoral Neck: An Unusual Cause of Pathologic Fracture.

The deposition of amyloid within human tissue can be detrimental to the proper functioning of multiple organ systems. While the infiltration of the amyloid protein within the musculoskeletal soft tissues can lead to compressive neuropathies, tendon irritation or rupture, and joint stiffness, pathologic fracture as a result of amyloid deposition in bone is a rare manifestation of amyloidosis. We present a case of pathologic fracture of the femoral neck from amyloid deposition in a 59-year-old male on chronic hemodialysis who was found to have lytic lesions in his proximal femur. At the time of hemiarthroplasty, histopathologic analysis of a femoral head sample revealed apple-green birefringence of the deposits under polarized light, consistent with amyloid deposition. Clinicians should have a high index of suspicion for the atypical presentation of amyloidosis in a patient on chronic hemodialysis with lytic bone lesions.

A 5-Year-Old Female With an Aneurysmal Bone Cyst of the Proximal Humerus.

An aneurysmal bone cyst (ABC) is a non-malignant, skeletal tumor that is extremely rare and most commonly presents within the first two decades of life. Genetic mutation of the USP6 gene on chromosome 17 remains to be the most commonly accepted reasoning as ABC's etiology remains unknown. As the radiographic appearance of ABC is quite similar to other kinds of bone cysts, a histological diagnosis is often required to attain a definitive diagnosis. Curettage remains the gold standard treatment with high chances of local recurrence. Evidence has shown the beneficial applications of administering a sclerosing agent. Further trials would improve the level of evidence available for physicians to make a better management plan. We have demonstrated the treatment of an aneurysm bone cyst of the proximal humerus on a 5-year-old female in this report, which might be utilized as a reference for future procedures.

Light-Chain Multiple Myeloma: A Diagnostic Challenge.

Light-chain multiple myeloma (LCMM) is a less frequent type of multiple myeloma (MM), with a more aggressive course and poorer prognosis. It is characterized by the inability of the malignant plasma cells to produce heavy chains, resulting in the exclusive production of light chains. Therefore, no M-spike is visible in serum protein electrophoresis. We described the case of a 67-year-old female who presents to the emergency department with anemia, severe renal insufficiency, and multiple lytic bone lesions. After three days, the diagnosis of kappa light chain multiple myeloma was made in a patient with elevated serum and urinary kappa light chains and a bone marrow aspirate with 21.7% of atypical plasma cells. The rapid diagnosis allowed prompt referral to a specialized multiple myeloma center and early initiation of treatment.

Classic Hodgkin lymphoma with initial extranodal osseous presentation: a case report and literature review.

Initial extranodal osseous presentation of Classic Hodgkin lymphoma (CHL) is extremely rare. The present study describes a case of CHL in an 11-year-old male presenting with lower back and right hip pain. Radiologic imaging showed a solitary lytic lesion involving the L5 vertebrae and sacrum. Pathologic examination led to a diagnosis of extranodal osseous CHL and further workup proved bone marrow and nodal disease. Diagnosis of extranodal osseous CHL is challenging, especially in this age group and location. When confronted with a solitary lytic bone lesion in a young patient, more common benign and neoplastic entities enter the differential diagnosis and include osteomyelitis, Langerhans cell histiocytosis, epithelioid hemangioma of bone, leukemia, and anaplastic large cell lymphoma (ALCL) among others, with extranodal osseous CHL being one of the less common entities in the differential diagnosis. This case report raises the awareness of extranodal osseous CHL as one of the entities to consider when confronted with a solitary lytic bone lesion in a young patient.

About an aggressive bone lesion.

We report here a case of hyperparathyroidism with disseminated brown tumors mimicking malignancy. The important clinical teaching of our case is that hyperparathyroidism can take various aspects. Plasma parathyroid hormone concentration should be measured in all patients with multiple bone lesions.

KSHV-associated extracavitary primary effusion lymphoma in an HIV seronegative patient: a case report and review of the literature.

Primary effusion lymphoma (PEL) is a rare type of non-Hodgkin's lymphoma presenting as a lymphomatous effusion and absence of a solid tumor mass. Extracavitary PEL (EC-PEL) is a subtype of PEL with the absence of an effusion but presence of solid tumor. PEL and EC-PEL share the same histopathologic and immunophenotypic features. Kaposi sarcoma-associated herpesvirus (KSHV) positivity is seen universally in these malignancies and is a requisite for diagnosis. Most cases are seen to occur in HIV positive individuals. We present a unique case of a 21-year-old male who presented with ongoing chest pain and right hip pain found to have an extensive lytic lesion of the right iliac bone, a paratracheal mass and a large pelvic mass. All the involved sites were FDG (F-18 fluorodeoxyglucose)-avid on PET-CT scan. The patient was seronegative for HIV with no risk factors for immunosuppression. A biopsy of the pelvic mass and bone marrow showed large atypical cells with irregular multi-lobulated nuclei, prominent nucleoli, and abundant amphophilic cytoplasm. The cells were positive for MUM1, in situ hybridization for EBV-encoded RNA (EBER), and KSHV, while negative for B-cell and T-cell markers. The patient was treated with six cycles of DA-EPOCH with a follow up PET scan showing a decrease in size of the masses and bone lesion and conversion to non-FDG-avid status. To the best of our knowledge, our case is the first in published English literature with bone involvement with EC-PEL regardless of HIV status. We review the reported cases of EC-PEL including their presentation, diagnostic features, treatment and outcomes.