Bilateral osteonecrosis of the external auditory canal caused by bone-modifying agents for cancer bone metastases.

A 51-year-old woman with a 54-month history of treatment with bone-modifying agents for thyroid cancer bone metastases, namely zoledronic acid for three months and denosumab for 51 months, presented with jaw pain, trismus, and ear discharge. Physical examination, bacterial culture, and radiological findings led to a diagnosis of osteonecrosis of the external auditory canal. Since the discontinuation of denosumab did not improve the diagnosed condition, she underwent surgical reconstruction.

Epigenetic disruption of adipogenic gene enhancers in dedifferentiated liposarcomas and its therapeutic value.

Liposarcoma (LPS) is the most common soft-tissue sarcoma in adults, and well-differentiated liposarcoma (WDLPS) and dedifferentiated liposarcoma (DDLPS) are the most frequent subtypes. These LPSs are considered to develop due to disturbances in the adipogenic differentiation of mesenchymal stem cells. However, the molecular mechanisms underlying the disturbances remain unclear.

A Novel Technique of Hip Disarticulation with a Stump with Soft Tissue of the Proximal Thigh: A Case Report.

Case: Two women (aged 35 and 29 years) with intractable chronic knee infection of tumor prostheses opted for amputation. As only the trochanteric region could be preserved, we resected the remaining proximal femur and created a 15-cm long stump using unaffected proximal thigh soft tissue to avoid the drawbacks of ultra-high-thigh amputation and conventional hip disarticulation. Both had no contracture, could move their stump voluntarily, and ambulated using a standard transfemoral prosthesis without a pelvic belt at 4-year and 3-year follow-ups, respectively.

A Case of Chondroblastoma in the Medial Condyle of the Femur Treated With an Intra-Articular Approach via the Intercondylar Fossa.

Adequate bone curettage is crucial for treating epiphyseal chondroblastomas. However, achieving adequate curettage while minimizing damage to the articular cartilage is challenging. For lesions at the center of the distal femoral epiphysis, curettage using an intercondylar approach may have better oncological and functional outcomes than the conventional extra-articular approach from the wall of the epiphysis.

Clinical characteristics and outcomes of patients with chondroblastoma undergoing surgery with various adjuvant procedures: a retrospective study of 59 cases.

Background: Chondroblastoma is classified as a benign bone tumor. However, postoperative local recurrence remains a concern. We analyzed the factors contributing to chondroblastoma local recurrence and the clinical challenges associated with treating these patients.

Early separation and parallel clonal selection of dedifferentiated and well-differentiated components in dedifferentiated liposarcoma.

Dedifferentiated liposarcoma (DDLPS) comprises a high-grade dedifferentiated (DD) component and a juxtaposed well-differentiated (WD) component. The DD component is believed to originate from the WD component by acquiring additional genomic alterations. In this study, we performed multiregion genome, epigenome, and transcriptome analyses of three patients with DDLPS.

Development of an Artificial Intelligence System for Distinguishing Malignant from Benign Soft-Tissue Tumors Using Contrast-Enhanced MR Images.

Introduction: The integration of artificial intelligence (AI) into orthopedics has enhanced the diagnosis of various conditions; however, its use in diagnosing soft-tissue tumors remains limited owing to its complexity. This study aimed to develop and assess an AI-driven diagnostic support system for magnetic resonance imaging (MRI)-based soft-tissue tumor diagnosis, potentially improving accuracy and aiding radiologists and orthopedic surgeons.

Methods: An experienced orthopedic oncologist and radiologist annotated 720 images from 77 cases (41 benign and 36 malignant soft-tissue tumors).

Bilateral Upper Arm Granulomas Induced by Leuprorelin Acetate Injection Mimicking Malignant Soft Tissue Tumors: A Case Report.

Leuprorelin acetate is a common anticancer medication used for prostate cancer treatment. One of the local adverse reactions after leuprorelin injection is the development of reactive granulomas, typically presenting as subcutaneous nodules. In this case report, we describe a 73-year-old patient with prostate cancer who developed unusually large sized intramuscular reactive granulomas, which mimicked malignant soft tissue tumors.

Additional Wide Resection of Infantile Dermatofibrosarcoma Protuberans after Unplanned Excision: A Case Report.

Dermatofibrosarcoma protuberans (DFSP) is a locally aggressive intermediate soft tissue neoplasm that occurs in the dermis. DFSP generally occurs in young to middle-aged adults and rarely in infancy. Because of its extreme rarity, DFSP is difficult to diagnose and treat, especially when it occurs in infancy.

A validation study for the utility of serum microRNA as a diagnostic and prognostic marker in patients with osteosarcoma.

In our previous study, osteosarcoma advanced locally, and metastasis was promoted through the secretion of large number of small extracellular vesicles, followed by suppressing osteoclastogenesis via the upregulation of microRNA (miR)-146a-5p. An additional 12 miRNAs in small extracellular vesicles were also detected ≥6× as frequently in high-grade malignancy with the capacity to metastasize as in those with a low metastatic potential. However, the utility of these 13 miRNAs for determining the prognosis or diagnosis of osteosarcoma has not been validated in the clinical setting.

Prediction of tissue-of-origin of early stage cancers using serum miRNomes.

Background: Noninvasive detection of early stage cancers with accurate prediction of tumor tissue-of-origin could improve patient prognosis. Because miRNA profiles differ between organs, circulating miRNomics represent a promising method for early detection of cancers, but this has not been shown conclusively.

Methods: A serum miRNA profile (miRNomes)-based classifier was evaluated for its ability to discriminate cancer types using advanced machine learning.

Bilateral Osteotomy of Pedicles for En Bloc Resection of a Malignant Tumor of the Posterior Thoracic Spine: A Case Report.

Case: A 45-year-old woman had a grade II chondrosarcoma (T2N0M0G2) located at the spinous processes and laminas of T3-6 with the tumor extension into the spinal canal at T3-4. To perform en bloc tumor resection, we released or disarticulated bilateral costovertebral ligaments from T3-6 and cut the bilateral pedicles at T3-5 all from posteriorly. Then, we completed en bloc resection without violating the tumor capsule.

Intramedullary osteoid osteoma in the humerus of a toddler-A case report and review of the literature.

Osteoid osteoma (OO) is a benign osteoblastic tumor characterized by nocturnal pain that responds well to non-steroidal anti-inflammatory drugs. This condition commonly affects adolescents and young adults, and patients between 5 and 24 years of age account for 85% of all OO cases; it occurs very rarely in patients under 5 years old. Tumors often occur in the cortical bone in the diaphysis and metaphysis of the appendicular skeleton and are more common in the lower extremities than upper extremities.

Dedifferentiated Osteosarcoma of the Distal Ulna: A Case Report.

Osteosarcoma is the most common malignant primary bone tumor that occurs most frequently in the second decade of life but rarely in patients over 40 years of age. The most common primary sites of osteosarcoma are the distal femur followed by proximal tibia and proximal humerus, and involvement of the wrist is extremely rare. Moreover, dedifferentiated osteosarcoma is also a rare condition that progresses to high-grade osteosarcoma from low-grade osteosarcoma, usually central low-grade osteosarcoma or parosteal osteosarcoma that bears MDM2 and/or CDK4 gene amplifications.

Radiological changes in the formation of Brodie's abscess by sequential magnetic resonance imaging: a case report.

Brodie's abscess is a relatively rare subacute form of osteomyelitis. Early diagnosis is challenging because of its insidious onset and vague symptoms. Magnetic resonance imaging is helpful in the diagnosis of Brodie's abscess; however, to date, no study has described the imaging findings of this disease in the early stage.