Giant Chondroid Syringoma Radiologically Mimicking Malignancy
A 59-year-old man presented with a painless mass on the anterior aspect of the upper thigh with a slow enlargement over the past 5 years []. Dermatological examination showed a relatively firm, mobile 5 × 3 cm nodule covered by normal skin. The patient was otherwise healthy. Laboratory studies including complete blood count, erythrocyte sedimentation rate (ESR), urine analysis, aspartate aminotransferase (AST), alanine aminotransferase (ALT), blood urea, creatinine were normal. The findings were suggestive of lipoma or liposarcoma. Sonographic examination revealed mixed, echogenic solid mass measuring approximately 4.5 × 3 × 2 cm. On Doppler ultrasound, there were vessels predominantly at the periphery of the mass. Magnetic resonance images (MRI) revealed a 4.7 × 2.9 × 2.2 cm, well-circumscribed, lobular mass that showed heterogeneous enhancement predominantly in the peripheral portion of the mass after intravenous contrast administration []. Diffusion-weighted imaging (DWI) showed areas of increased signal intensity that were indicative of a highly cellular tumor []. According to the MRI findings, we considered benign subcutaneous lipomatous tumors with cystic and solid components such as angiolipoma or fibrolipoma or well-circumscribed low-grade soft tissue liposarcoma without surrounding tissue extension in our differential diagnosis. Because the vascularity of the lesion and heterogeneous pattern with contrast enhancement on MRI examination, we excluded lipoma.\nWe decided to perform trucut biopsy. Histopathological examination revealed a group of cells, which have eosinophilic cytoplasm and regular small nuclei, exhibited epithelial-like pattern in the myxoid stroma. Many of the properties were lipomatous. However, as adipocytes were variable in size and focally showed a lipoblast-like appearance, some tumor areas were reminiscent of a well-differentiated lipoma-like liposarcoma [].\nThe patient underwent surgical excision of the mass. Histologically, the tumor was confined to the subcutaneous tissue. The adjacent tissue appeared normal. There were irregular epithelial nests and tubuloalveolar structures in a chondromyxoid stroma. There was also abundant fibrolipomatous stroma. There were foreign body reactions against the epidermoid cysts within the tumor and surrounding tissue. There were no atypical mitoses or necrosis [Figures and ].