Spindle cell carcinoma as a locally recurrent malignancy after surgery for early lingual squamous cell carcinoma.

Spindle cell carcinoma (SpCC) of the tongue is a relatively rare malignancy. We treated a patient with metachronous early squamous cell carcinoma (SCC) in both margins of the tongue (right side first followed by left side). Eight years after treatment for the first SCC by surgery and radiotherapy, the second SCC occurred in the contralateral margin of the tongue. Surgical resection was performed for the second SCC, with local recurrence 8 months later associated with pathological change from SCC to SpCC. The SpCC was completely resected with wide surgical margins in combination with bilateral neck dissection. However, the patient developed pulmonary metastasis and died of respiratory failure 4 months after the final surgery. Postoperative inflammatory reaction followed by scar formation in the previously irradiated surgical site might have caused the transition from SCC to SpCC during the process of recurrence.