Thyroid and Parathyroid Functions After Pharyngo-Laryngo-Esophagectomy for Cervical Esophageal Cancer

Background: Cervical esophageal cancer (CEC) patients whose larynx function cannot be preserved often undergo chemoradiotherapy, whereas those with residual or recurrent lesions undergo a pharyngo-laryngo-esophagectomy (PLE); however, some need to undergo a pharyngolaryngectomy with total esophagectomy (PLTE) for synchronous or metachronous esophageal cancer. We retrospectively evaluated the relationship between preoperative irradiation (or the extent of esophageal resection) and postoperative endocrine complications in CEC, including hypothyroidism and hypoparathyroidism. Methods: The cancers of 35 (5.4%) of 678 esophageal cancer patients with esophagectomy treated in 2000–2017 were CECs. We also analyzed the 17 cases of CEC patients who underwent PLE with thyroid lobectomy—11 with irradiation before PLE and 6 without irradiation. Seven patients underwent a PLTE. Results: Hypothyroidism and hypoparathyroidism occurred in 14 and 12 patients, respectively. The hypothyroidism rate was significantly higher in patients with irradiation versus those without irradiation (100% vs. 50%; p = 0.010), and the hypoparathyroidism rate was significantly higher in the PLTE versus non-PLTE patients (100% vs. 50%; p = 0.026). The mean levothyroxine dosage was 1.60 μg/kg/day in the PLE patients post-irradiation. Conclusions: Irradiation appears to be a risk factor for hypothyroidism after PLE with thyroid lobectomy, while PLTE might have some effect on hypoparathyroidism. Due to vocal function loss, PLE patients may experience symptoms from endocrine complications. Levothyroxine treatment soon after PLE for post-irradiation patients and patients requiring as-needed calcium or vitamin D supplementation based on biochemical hypocalcemia for PLE (especially PLTE), may be effective in preventing symptomatic endocrine complications.