Thyroid dysfunction after intra-arterial chemotherapy for hypopharyngeal and laryngeal cancer

Hypothyroidism is a late side effect after curative radiotherapy in the head and neck region. Superselective intra-arterial chemotherapy (SSIAC), when combined with radiation (SSIAC-R), shows higher control potential for locally advanced head and neck cancers, which is attributable to a delivery of higher concentrations of chemotherapeutic agents. However, it could enhance damages in the normal tissues. Hypothyroidism is a late adverse effect after curative radiotherapy in the head and neck region. This study focuses on the toxic effect of treatment modality for thyroid function.

A retrospective analysis was performed to examine patients' thyroid function after SSIAC-R for laryngeal and hypopharyngeal cancer.

Hypothyroidism was observed in 21 (77.8%) of 27 patients receiving SSIAC-R, 4 (33.3%) of 12 patients treated with radiation alone, and 7 (41.1%) of 17 who underwent systemic chemoradiotherapy. The number of administered vessels significantly correlated with the incidence of developing hypothyroidism among SSIAC-R treated patients (P=0.03).

Concurrent setting of SSIAC with radiation significantly raises the possibility of hypothyroidism. Therefore, monitoring late complications of therapeutic procedures is essential during follow-up visits.