Synovial chondromatosis of the temporomandibular joint: CT and MRI findings.

We report a rare case of synovial chondromatosis of the temporomandibular joint (TMJ) in a 31-year-old man. CT examination showed a mixed soft tissue mass with small calcifications near the right TMJ joint space. MR images revealed a heterogeneous mass on the different sequences and, after contrast administration, originating in the right TMJ. Cytology showed chondroid cellularity. The lesion was surgically removed and final histological study demonstrated the diagnosis of a synovial chondromatosis. We highlight the importance of the complementary findings from CT and MR, especially the important specific feature described for TMJ synovial chondromatosis related to the mixed density within the mass, in order to perform an accurate preoperative diagnosis whenever there is an absence of ossified loose bodies.

Diagnóstico radiológico de la cavidad ósea de Stafne

La cavidad ósea de Stafne (COS) es un defecto óseo mandibular de evolución estable que constituye una lesión pseudoquística o pseudotumoral. Se describen tres pacientes con COS estudiados por TC. La lesión presenta unas características típicas: localización característica en ángulo mandibular debajo del canal mandibular sin patología asociada y con abertura a cara lingual mandibular. Si los datos de la ortopantomografía sugieren un COS se debe realizar una TC para confirmar el diagnóstico evitando la realización de procedimientos agresivos quirúrgicos (AU)

Massive crystal-storing histiocytosis associated with low-grade malignant B-cell lymphoma of MALT-type of the parotid gland.

Massive crystal deposition is unusual in lymphoproliferative disorders. In this report, a mucosa-associated lymphoid tissue (MALT) low-grade B-cell lymphoma of the parotid gland containing large numbers of crystal-storing histiocytes is described. The patient, an 81-yr-old female, presented with a history of long-standing left parotid gland enlargement. FNA cytology of the tumor showed a lymphoplasmacytic infiltrate and sheets of large benign histiocytes with abundant eosinophilic intracytoplasmic inclusions. Paraffinsection immunohistochemistry performed on the cell block demonstrated that the histiocytic cells were immunoreactive for the KP-1 (CD-68) antibody and monotypic for cytoplasmic IGM and L-light chain. The cytological diagnosis was consistent with a low-grade B-cell lymphoma with plasmacytic differentiation associated with crystal-storing histiosis. A periparotid lymph node was biopsied and showed involvement by a monocytoid B-cell lymphoma with plasmacytic differentiation and crystal-storing histiocytosis in the pericapsular region.

Plasma-cell tumours of the condyle.

Plasma cell tumours are a group of disorders which are characterized by neoplastic proliferation of atypical plasma cells involved in the production of monoclonal immunoglobulins. Bone pain, renal insufficiency and normocytic-normochromic anaemia are suggestive data for diagnosis. In 12-15% of cases of multiple myeloma, the first manifestation of the disease appears in the jaw bones and oral cavity. Two cases of multiple myeloma affecting the mandibular condyle are presented, and the incidence of oral and maxillofacial lesions is briefly reviewed.