Malignant chondroid syringoma: report of a case with lymph node metastasis 12 years after local excision.

A 46-year-old man noticed a nodule on his sole. The nodule was removed and the specimen showed a lobular proliferation of tumor cells with glandular differentiation embedded in mucinous stroma. A diagnosis of chondroid syringoma was made. Twelve years later, he noted a swelling in the right inguinal region. The mass was surgically removed. The histopathological findings of the lymph node showed the more atypical tumor cells in the mucoid stroma. Upon reexamination, the primary tumor contained malignant chondroid syringoma (MCS) cells; the tumor cells metastasized to lymph node. MCS is rare with 43 reported cases in the literature. The site of the primary tumor was the lower extremity in 35 percent, the head in 28 percent, and the upper extremity in 23 percent. The percentage of malignant cases with local recurrence, nodal metastasis, and distant metastasis was 49 percent, 42 percent, and 40 percent, respectively. In these cases, the average time period until disease recurrence was 23 months, 50 months, and 66 months for local recurrence, nodal metastasis, and distant metastasis, respectively. Of these, 23 percent of the cases succumbed. As MCS may progress very slowly and disease recurrence including metastasis occurs in a relatively high percentage of cases, long-term follow-up of MCS cases is required.