Abstract
Human T-cell leukemia virus type 1 (HTLV-1) is known to cause adult T-cell leukemia (ATL). Several cases of ATL in the oral cavity have so far been reported. In addition, because ATL has been frequently reported to be complicated with solid cancer, ATL should be ruled out in patients who are HTLV-1 carriers and who are suspected of having an oral malignant tumor.
A 44-year-old female who was an HTLV-1 carrier presented with a two-week history of a mass on her tongue. Our initial examination revealed a 30 × 20mm, indurated mass on the left side of the tongue. The laboratory data indicated anti HTLV-1 antibody to be positive and atypical lymphocytes were detected in 1% of the white blood cells in a blood smear preparation. The clinical-diagnosis was a malignant tumor in the tongue. A tongue biopsy revealed squamous cell carcinoma. Polyclonal integration of HTLV-1 proviral DNA was detected by Southern blotting of both a biopsy specimen and peripheral blood, thus ATL could be ruled out.
The preoperative diagnosis was tongue cancer (T2N2bM0). A tongue sub-total resection and left neck dissection and reconstruction were therefore performed. During adjuvant radiotherapy, right cervical lymph node metastasis appeared. As a result, a right neck dissection and adjuvant radiotherapy to the right neck were performed. Unfortunately, bone and lung metastasis occurred and the patient died 12 months after our initial examination.
These findings suggest that a chronic HTLV-1 infection may therefore compromise cellular immunity, thereby accelerating the progression of cancer.
