ES15 *RECURRENT LARYNGEAL NERVE PARALYSIS AND DELAYED PRESENTATION OF THYROID CANCER

Abstract

Background: Recurrent laryngeal nerve paralysis (RLNP) is well recognized as a presenting symptom of thyroid malignancy, however RLNP is more commonly due to other aetiologies such as post‐viral paralysis. The onset of a hoarse voice in a patient with a presumed benign multinodular goiter can thus present diagnostic difficulties and may lead to significant delays in the diagnosis of thyroid cancer.Methods: Data were obtained from the University of Sydney Endocrine Surgical Unit database. The study group comprised all patients presenting with a pre‐operative diagnosis of RLNP prior to thyroid surgery in the 10 year period 1999 to 2008.Results: During the study period there were 44 thyroidectomies performed in cases of preoperative RNLP. 16 of these patients (36%) had cancer on final pathology with 14 having well differentiated thyroid cancer. In 3 (18%) of these patients the diagnosis was markedly delayed due to associated multinodular goiter. Mean delay from onset of RLNP to diagnosis of cancer in these 3 patients was 7 years (range 3 to 9 years). Each of these patients had normal neck CT, thyroid nodules of < 8 mm on initial imaging and initial benign FNA. In all 3 patients intra‐operative findings noted tumour posteriorly at the Tubercle of Zuckerkandl and histopathology confirmed invasion of the nerve by papillary carcinoma.Conclusion: RLNP may be a sign of occult malignancy in the Tubercle of Zuckerkandl. Small tumour size and posterior location on the gland make reliable imaging and FNA difficult. Patients in whom malignancy is initially excluded should have close follow up and reassessment as there is a significant false negative rate in this patient cohort.