Osteochondromas are common and typically arise from the metaphyseal ends of long bones. An osteochondral neoplasm of the soft tissue, which is a lesion of uncertain pathogenesis, is uncommon and usually arises from the synovial tissue in joints and tendon sheaths. Rarely, extraskeletal osteochondromas also arise outside of synovial compartments. Most of the reported cases were presented in the hands and feet, especially in the fingers. Here we describe a 44-yr-old female patient who presented with a pain in the left buttock. A well-defined osseous mass was detected in the buttock. It consisted of sharply demarcated, mature hyaline cartilage that was covered with a fibrous capsule, which changed gradually into cancellous bone, more pronouncedly at the center. The diagnosis of an extraskeletal osteochondroma should be considered when a discrete, ossified mass is localized in the soft tissues. A case of pathologically proven extraskeletal osteochondroma of the buttock is presented with a literature review, magnetic resonance imaging, and radiological findings.
Accidental Falls ; Adult ; Buttocks* ; Diagnosis, Differential ; Female ; Human ; Myositis Ossificans/diagnosis ; Osteochondroma/complications ; Osteochondroma/diagnosis* ; Osteochondroma/radiography ; Osteochondroma/surgery ; Pain/etiology ; Sarcoma/diagnosis ; Soft Tissue Neoplasms/complications ; Soft Tissue Neoplasms/diagnosis* ; Soft Tissue Neoplasms/radiography ; Soft Tissue Neoplasms/surgery

Here, we describe a popliteal mass that was initially misdiagnosed as a simple popliteal cyst, which finally turned out to be osteochondrolipoma. A 63-year-old housewife presented with sustained knee pain in association with a palpable mass on the popliteal fossa. The mass was in the posteromedial area and soft, non-tender, non-movable in the posteromedial area. Using plain radiography, the mass appeared as a round, soft tissue density lesion containing bony fragments. We performed an ultrasound-guided needle biopsy in conjunction with magnetic resonance imaging, followed by an open excisional biopsy. Microscopically, histological sections showed a lipoma with cartilaginous and osseous differentiation, finally diagnosed as osteochondrolipoma. In conclusion, popliteal masses are not always simple cysts, and the evaluation of masses in the popliteal fossa is always necessary.
Female ; Humans ; Lipoma/complications/*diagnosis ; Middle Aged ; Osteochondroma/complications/*diagnosis ; Popliteal Cyst/etiology ; Soft Tissue Neoplasms/complications/*diagnosis

Any medical diagnosis should take a multimodal approach, especially those involving tumour-like conditions, as entities that mimic neoplasms have overlapping features and may present detrimental outcomes if they are underdiagnosed. These case reports present diagnostic pitfalls resulting from overdependence on a single diagnostic parameter for three musculoskeletal neoplasm mimics: brown tumour (BT) that was mistaken for giant cell tumour (GCT), methicillin-resistant Staphylococcus aureus osteomyelitis mistaken for osteosarcoma and a pseudoaneurysm mistaken for a soft tissue sarcoma. Literature reviews revealed five reports of BT simulating GCT, four reports of osteomyelitis mimicking osteosarcoma and five reports of a pseudoaneurysm imitating a soft tissue sarcoma. Our findings highlight the therapeutic dilemmas that arise with musculoskeletal mimics, as well as the importance of thorough investigation to distinguish mimickers from true neoplasms.
Adult ; Aneurysm, False ; diagnosis ; Biopsy ; Bone Diseases ; diagnosis ; Bone Diseases, Metabolic ; diagnosis ; Bone Neoplasms ; diagnosis ; Cell Proliferation ; Diagnosis, Differential ; Diagnostic Errors ; prevention & control ; Female ; Giant Cell Tumors ; diagnosis ; Humans ; Hyperparathyroidism ; complications ; Leukocytosis ; diagnosis ; Male ; Methicillin-Resistant Staphylococcus aureus ; Middle Aged ; Neoplasms ; diagnosis ; microbiology ; Osteomyelitis ; diagnosis ; microbiology ; Osteosarcoma ; diagnosis ; Sarcoma ; diagnosis ; Soft Tissue Neoplasms ; diagnosis ; Tibia ; pathology

Aged ; Carcinoma, Renal Cell ; pathology ; Carcinosarcoma ; pathology ; Chondroma ; pathology ; Chondrosarcoma ; complications ; metabolism ; pathology ; surgery ; Diagnosis, Differential ; Female ; Humans ; Kidney Neoplasms ; complications ; metabolism ; pathology ; secondary ; surgery ; Lung Neoplasms ; secondary ; Nephrectomy ; Pleural Effusion, Malignant ; etiology ; S100 Proteins ; metabolism ; Soft Tissue Neoplasms ; pathology ; Vimentin ; metabolism

Transcatheter arterial chemoembolization (TACE) has been used widely to treat patients with unresectable hepatocellular carcinoma. However, this method can induce various adverse events caused by necrosis of the tumor itself or damage to nontumor tissues. In particular, neurologic side effects such as cerebral infarction and paraplegia, although rare, may cause severe sequelae and permanent disability. Detailed information regarding the treatment process and prognosis associated with this procedure is not yet available. We experienced a case of paraplegia that occurred after conducting TACE through the intercostal artery to treat hepatocellular carcinoma that had metastasized to the rib. In this case, TACE was attempted to relieve severe bone pain, which had persisted even after palliative radiotherapy. A sudden impairment of sensory and motor functions after TACE developed in the trunk below the level of the sternum and in both lower extremities. The patient subsequently received steroid pulse therapy along with supportive care and continuous rehabilitation. At the time of discharge the patient had recovered sufficiently to enable him to walk by himself, although some paresthesia and spasticity remained.
Antiviral Agents/therapeutic use ; Bone Neoplasms/radiography/secondary ; Carcinoma, Hepatocellular/diagnosis/pathology/*therapy ; Catheter Ablation ; Chemoembolization, Therapeutic/*adverse effects ; Hepatitis B/complications/drug therapy ; Humans ; Liver Cirrhosis/etiology ; Liver Neoplasms/diagnosis/pathology/*therapy ; Male ; Middle Aged ; Positron-Emission Tomography ; Soft Tissue Neoplasms/secondary ; Spinal Cord Injuries/*etiology ; Tomography, X-Ray Computed