The Incidence of Thyroid Cancer in Simple Multi-Nodular Goitre;
Evidence from a Single Centre
R J Egan, J E Coulston. J D Morgan.
Department of Endocrine Surgery, North Bristol NHS Trust, Bristol, BS10 5NS
Multi-nodular goitre has long been known to be associated with an increased risk of thyroid cancer. Recent work has suggested that up to 16.6% of multi-nodular goitres (MNG) are associated with incidental findings of thyroid cancer. It has also been stated that up to 50% of certain thyroid malignancies are found on the background of MNG. Our group feels that such data over-estimates the link between MNG and thyroid cancer.
To ascertain the incidence of thyroid cancer in patients treated in our centre with total thyroidectomy for suspected MNG.
We looked retrospectively at all patients who underwent total thyroidectomy in our tertiary referral centre, under a single endocrine surgeon. Of these, 102 patients with a primary pre-operative diagnosis of MNG were identified. Patients under 18 were excluded. In total 84 females, and 18 males, with a mean age of 55.2 years (range 19-85) were included for analysis. Pathology reports, clinical notes, and FNAC (fine needle aspiration cytology) reports for each were then reviewed.
Three patients were identified as having incidental thyroid cancer from our cohort; a rate of 2.9%. Two patients had micropapillary carcinomas and one a minimally invasive follicular carcinoma. None of these cancers were associated with a dominant or disproportionate nodule within a MNG. None of these patients had any suspicious features (clinically or radiologically) pre-operatively, and none had been investigated with FNAC.
Our results demonstrate that with accurate pre-operative assessment and imaging by a designated multi-disciplinary team, rates of incidental cancer in post-thyroidectomy specimens for simple multi-nodular goitre are very low.