ABSTRACT
Chondromyxoid fibroma (CMF) is a rare benign cartilaginous tumor that usually arises from the metaphysis of long bones. In rare cases, however, CMF presents in unusual locations, such as the facial bones and sinonasal tract. We present a case of a 60-year-old woman with a CMF of the nasal septum. The initial radiographic findings were suggestive of a vascular tumor or a malignancy, but microscopic examination revealed the typical pathologic features of CMF, and SOX9 immunostaining confirmed its cartilaginous origin. The tumor was successfully excised, and the patient was free of disease at 12-month follow-up. Recognizing CMF is important when it presents in unexpected locations, especially because of its histologic resemblance to chondrosarcoma. We believe that the use of SOX9 in our case assisted in the recognition of the chondroid nature of the lesion and facilitated the diagnosis of CMF.
Subject(s)
Chondroma/pathology , Fibroma/pathology , Nasal Septum/pathology , Paranasal Sinus Neoplasms/pathology , Chondroma/diagnostic imaging , Chondroma/surgery , Diagnosis, Differential , Female , Fibroma/diagnostic imaging , Fibroma/surgery , Humans , Immunohistochemistry , Middle Aged , Nasal Septum/diagnostic imaging , Nasal Septum/surgery , Paranasal Sinus Neoplasms/diagnostic imaging , Paranasal Sinus Neoplasms/surgery , SOX9 Transcription Factor/analysis , Tomography, X-Ray Computed , Treatment OutcomeABSTRACT
Mucoepidermoid carcinoma (MEC) comprises approximately 30% of all salivary gland malignancies, making it the most common malignant tumor of the salivary glands. Multiple histologic variants with a wide range of differentiation have been described. Sclerosing MEC (SMEC) is a rare subtype that may be misdiagnosed as a benign reactive condition or low-grade non-SMEC malignancy. We report 4 cases of SMEC and evaluated them with Her-2/neu and MIB-1 to determine whether an association exists between the histologic grade and immunohistochemical findings. In 3 cases, histologic examination demonstrated relatively well-circumscribed, nonencapsulated tumors composed of extensive central sclerosis with keloid-like stroma and scattered epithelial islands of low-grade MEC. In the fourth case, the tumor showed similar sclerotic stroma; but the epithelial component was of intermediate grade. In all 4 cases, eosinophils and neutrophils were part of the inflammatory infiltrate; and the edges were surrounded by lymphoid tissue, with germinal center formation and residual epithelial islands. A Mayer mucicarmine stain revealed abundant intracytoplasmic mucin. We found MIB-1 labeling indices of 5% or less in cases 1, 2, and 3 and 12% in case 4, suggesting an association between MIB-1 index and tumor grade. The tumors were negative for Her-2/neu in all 4 cases. The latter seems to bear no relationship to tumor grade.
