Adult T-cell leukemia/lymphoma in patients with head and neck cancer after S-1 chemotherapy.

OBJECTIVE: One in 1000-3000 carriers of human T-cell leukemia virus type 1 (HTLV-1) develops adult T-cell leukemia/lymphoma (ATLL) per year; however, the pathogenic mechanism is not completely clear. We have observed that some patients with squamous cell carcinoma (SCC) develop ATLL during treatment at our hospital. The aim of this study was to examine treatment factors associated with onset of ATLL through an evaluation of the therapeutic background of these patients.

METHODS: The impact of radiotherapy, chemotherapy and surgery on occurrence of ATLL was evaluated in 146 patients with head and neck SCC who were treated at our hospital between April 2010 and December 2013.

RESULTS: Of 146 patients, 17 were HTLV-1 positive and 6 developed ATLL. There was a significant relationship between ATLL development and administration of S-1 chemotherapy (p=0.0003), but not with use of radiotherapy, surgery or other drugs.

CONCLUSION: The involvement of S-1 chemotherapy in ATLL development suggests that a test for HTLV-1 antibody should be performed before treatment and that S-1 should not be administered in HTLV-1 positive patients with head and neck carcinoma.