Promotion of Bone Lesions Through the Myeloma Integrin α6-Mediated Osteolytic Signaling

Osteolytic destruction is a hallmark of multiple myeloma and impairs myeloma patients’ quality of life. However, the molecular mechanism underlying the pathogenesis of myeloma-associated bone disease remains unclear. In this study, we demonstrate the role of myeloma cell-expressed integrin α6 in bone. Integrin α6 binds to laminin 8 and epidermal growth factor receptor on mesenchymal stem cells (MSCs) to form a trimer complex and upregulates the secretion of osteolytic cytokines from both myeloma cells and MSCs, leading to enhanced bone resorption and reduced bone formation. Thus, this study elucidates an important mechanism for myeloma-induced bone lesions and implicates that targeting integrin α6 may be a viable approach for bone healing in myeloma patients.

Imaging Diagnosis and Differentiation of Desmoplastic Fibroma of Bone

Background: To analyze the imaging features of desmoplastic fibroma of bone (DFB) for correct diagnosis. Methods: The plain radiography, computed tomography (CT) and magnetic resonance imaging (MRI) of 20 patients with DFB were retrospectively analyzed. Results: Twenty patients with DFB were retrieved including eleven males and nine females with an age range of 2-52 years (median 27). The DFB involved the femur in six patients, ilium in five, tibia in four, humerus in two, lumbar vertebra in one, radius in one, and calcaneus in the remaining one. DFB was common in the metaphysis of long bones could involve the diaphysis and epiphysis. The imaging presentations were divided into four types: the cystic expansile destruction, osteolytic destruction, mixed destruction, and paraosseous destruction. CT value was 30 -60 Hu in the lesion area (6 cases CT value＞45Hu). MRI had low mixed signals on T1WI and high mixed signals on T2WI. Soft tissue masses might be present in DFB. Conclusions: DFB is a rare tumor with strong local aggressiveness, imaging presentation of cystic bone destruction, low signals on T1WI and T2WI in the lesion, which are helpful for diagnosis of the disease and differentiation from other ones.

A Talaromyces marneffei infection with osteolytic lesions in an HIV-negative patient at non-endemic areas: A case report

Talaromyces marneffei infection is an endemic opportunistic infection for immunodepression patients, especially HIV-positive patients. Our case describes an unendemic and HIV-negative patient who presented with fever, subcutaneous mass, osteolytic destruction of the skull and subcutaneous abscess penetrating the diseased skull. The growth of Talaromyces marneffei was identified by the culture of the frontal pus, sputum, blood and bone marrow. Due to severe nausea and vomiting during the use of amphotericin B, voriconazole was finally selected for treatment. Two weeks after intravenous infusion of voriconazole injection, the patient was given oral voriconazole tablets for 5 months. After the initial intravenous treatment of voriconazole, the patient developed increased dyspnea and required ventilator support with endotracheal intubation, and methylprednisolone was given intravenously for 5 days. All lesions absorbed and no obvious discomfort was found during the follow-up at the third month after discharge. At present, the patient has been followed up for more than 3 years without recurrence. The case aims to raise doctors’ awareness of this rare disease in non-endemic areas and HIV-negative patients.

Percutaneous restoration of bone continuity with screws and PMMA cement in an extensive destruction of the pelvis

We report a case of combined percutaneous screw placement and cementoplasty guided by CT and fluoroscopy in a 66-year-old man with extensive osteolytic destruction of the right iliac bone and sacral wing due to metastasic infiltrative vesical carcinoma. The medical condition was responsible for very limited and painful walking. Two perpendicular screws were inserted into the iliac bone and sacroiliac joint, and bone cement injection was used to anchor the screws and restore the mechanical continuity of the pelvis ring. This minimally invasive procedure allowed for significant and rapid resumption of painless walking.

Tuberculosis of the Temporomandibular Region

Objective: To describe a unique case of extrapulmonary tuberculosis (TB) of the temporomandibular area focusing on its insidious and destructive course over a 2-year period with insights into the diagnostic and therapeutic pitfalls encountered throughout its clinical development. Methods: Study Design: Case Report Setting: Tertiary Government Hospital Patient: One Results: A 33-year old man initially presented with right pre-auricular swelling and trismus that were unresponsive to antibiotic therapy. On subsequent follow-ups, initial symptoms were accompanied by a non-healing right pre-auricular wound, right ear discharge, trismus, and right facial paralysis (House-Brackmann III). Cranial and temporal bone computed tomography scans revealed osteolytic destruction of the right temporomandibular region extending to the auditory canal and of the right mastoid bone extending to the right mandibular condyle and parotid. Infected malignancy of the parotid, mandible and temporal bone were considered, but definitive diagnosis from an incision biopsy revealed caseating granulomatous inflammation consistent with tuberculosis. He was started on anti-tuberculosis medications with significant resolution of pre-auricular swelling, non-healing pre-auricular wound, facial paralysis and ear discharge but minimal improvement in mouth opening. Conclusion: Tuberculosis of temporomandibular region is rare and is associated with nonspecific manifestations. Delay in diagnosing and initiating appropriate treatment can lead to morbidity and serious complications involving destruction of the temporal bone, middle ear, mandible and parotid gland over its progression. A high index of suspicion by the physician and awareness of the patient’s health seeking behaviors could have aided in the early diagnosis and treatment of this extrapulmonary TB. Keywords: tuberculosis, temporomandibular region, pre-auricular swelling, trismus, antituberculosis therapy, facial paralysis, chronic mastoiditis, ear discharge

Malignant Transformation of Benign Intraosseous Schwannoma in the Cervical Spine: A Case Report with an Immunohistochemical Study

Although 3% to 30% of lesions in von Recklinghausen disease undergo malignant transformation, malignant transformation of benign solitary schwannoma is extremely rare. We reported a case of recurrence and malignant transformation in a benign intraosseous schwannoma arising in the cervical spine of a 44-year-old man. The patient presented giant tumor in the C3 vertebral body with aggressive, expansile, and osteolytic destruction and relapsed 2 years after surgical resection and spinal reconstruction. Clinical data, radiologic characteristics, surgical management, histopathologic and immunohistochemical features were noted in the duration of follow-up. The local recurrence, nuclear pleomorphism, epithelioid differentiation, a small number of positive S-100 protein-staining cells, and especially the high percentage of positive cells with p53 (80%) and Ki-67 (75%) proteins support the aggressive nature of the lesion in malignant transformation of benign intraosseous schwannoma in the cervical spine. Immunohistochemistry would be useful as an ancillary technique in diagnosis. It is our practice to suggest that such case has to be carefully resected and the patient followed up.