Weight loss during concomitant chemo-radiation therapy for squamous cell head and neck cancer: Possible role of transient hyperthyroidism

Abstract

16531 Background: Concomitant Chemoradiotherapy (CRT) is a standard treatment modality for locally advanced squamous cell head and neck cancer (HNC). This treament is often associated with significant weight loss which is commonly attributed to nutritional depletion secondary to mucositis, pain and inadequate oral intake. We undertook an evaluation of thyroid function as measured by Thyroid Stimulating Hormone (TSH) levels during CRT to evaluate the possible role of a thyroid hormone flare during treatment that may account for part of this weight loss. Methods: Institutional Review Board approval was obtained to conduct this retrospective analyses. Patients treated at our institution during the past six months who were treated with CRT for HNC and had recorded TSH levels at baseline (when available), mid treatment (week 4 to 6 of CRT), and post CRT (6 to 9 weeks later), at least 5% weight loss during treatment, and feeding tube requirement data available were identified. Age, Gender, Stage and Primary site of disease, Radiation dose and fields, chemotherapy regimen, were recorded. Results: Twelve patients were identified. Mid treatment TSH levels were suppressed below normal reference range (0.49–4.67 mIU/L) in 7of 12 pts (58%). A decline in TSH levels was noted in all 8 of 8 pts (100%) that had recorded pre-CRT TSH levels and mid treatment levels. Improvement of TSH levels was noted in all 9 of 9 patients that had mid treatment and post treatment TSH levels recorded, although in three of these nine patients TSH levels remained below normal range. Four of twelve pts required PEG placements for nutritional support. Conclusions: Transient suppression of TSH levels suggesting a thyroid flare is frequently observed early during CRT for HNC and appears to improve by 6–9 weeks post treatment. This may contribute to weight loss in this nutritionally challanged population. Further studies evaluating more specialised thyroid function testing to exclude sick euthyroid states and other etiologies for suppressed TSH levels are warranted. In addtion, therapeutic methods to abbrogate this flare may reduce weight loss during aggressive CRT treatment protocols. No significant financial relationships to disclose.