Does autoimmune thyroid disease affect parathyroid autotransplantation and survival?

BACKGROUND: While the increased risk to parathyroid gland preservation has long been recognized during surgery for thyroid cancer, the effect of different benign pathological conditions on parathyroid preservation has not previously been reported. The aim of this study was to examine parathyroid viability in relation to autoimmune thyroid disease. METHODS: This is a retrospective cohort study including all patients having an initial total thyroidectomy (TT) performed by this unit during the period 2004-2005. RESULTS: A total of 628 patients underwent TT in the study period. For the Graves' disease cases, 45 (62.5%) required the autotransplantation of one or less parathyroid gland, whereas 27 (37.5%) required two or more glands to be autotransplanted. This was significantly higher than for the benign thyroid disease group in which the respective figures were 242 (77.6%) and 70 (22.4%) (P= 0.01). Of the lymphocytic thyroiditis cases, 61 (65.5%) required the autotransplantation of one or less gland, whereas 32 (34.4%) required the autotransplantation of two or more glands. This was also significantly higher (P= 0.03). Temporary hypocalcaemia was significantly higher when two or more glands were autotransplanted (23 out of 177, 13.2%) than one or less gland autotransplanted (18 out of 451, 4.0%, P < 0.01). However, the overall incidence of permanent hypoparathyroidism was 1.0%, and there was no significant difference between the groups. CONCLUSION: TT performed for Graves' disease and lymphocytic thyroiditis results in the autotransplantation of more parathyroid glands, leading to a higher incidence of temporary hypocalcaemia post-operatively. Despite this, the incidence of permanent hypoparathyroidism remains low at 1%.

The Delphian lymph node in thyroid cancer.

OBJECTIVE: To determine the significance of Delphian lymph node (DLN) involvement in thyroid cancer. SUMMARY BACKGROUND DATA: The DLN has long been regarded as a predictor of thyroid malignancy and indicator of advanced disease; however, there are no published data in relation to the thyroid. METHODS: A retrospective cohort study with data obtained from the University of Sydney Endocrine Surgery database and histopathology records. The study cohort comprised 1000 consecutive patients undergoing total thyroidectomy. RESULTS: The DLN was separately removed and identified as such in 263 of 1000 (26.3%) patients. Of 1000 patients 203 (20.3%) had a diagnosis of papillary/medullary cancer. Of this group 150 patients had surgery performed for suspected cancer, and in 53 the diagnosis of cancer was unsuspected. In only 1 case did the DLN operative appearance alert the surgeon to an otherwise unsuspected thyroid cancer. The DLN was separately identified in 103 patients with cancer and, in this group, 22 of 103 (21.4%) had DLN metastases. DLN involvement was associated with greater nodal disease (9.8 vs. 1.6 nodes; P < 0.001), larger tumor size (19.4 vs. 11.1 mm; P < 0.003) and younger age (41 vs. 47 years; P = 0.058). DLN involvement was highly predictive of further disease in the central compartment (sensitivity = 41%, specificity = 95%), moderately predictive of further disease in the lateral compartment (sensitivity = 50%, specificity = 88%), and strongly suggestive of further nodal disease in the neck (sensitivity = 64%, specificity = 100%). CONCLUSIONS: Although the clinical appearance of the DLN is not an accurate indicator of the presence of unsuspected thyroid cancer, metastatic involvement of the DLN is an adverse prognostic marker in papillary/medullary thyroid cancer. The presence of DLN metastasis in patients with thyroid cancer should alert the surgeon to the high probability of advanced disease and need for greater attention to the central and lateral lymph node compartments.

The University of Sydney Endocrine Surgery Database: 50 years of data accrual.

Surgical databases are now a fundamental part of clinical practice and research but have only been commonplace in the past decade or so. The University of Sydney Endocrine Surgery Database has now been in existence for more than 50 years since it was started by Tom Reeve in 1957. It includes comprehensive documentation of every aspect of every thyroid, parathyroid and adrenal procedure carried out by its surgeons while they were active members of the unit. During those 50 years, 17,466 such procedures have been documented. In the first year of data collection, only 20 thyroid procedures carried out by one surgeon in one hospital were entered, whereas in the most recent year, 1092 major endocrine procedures carried out by three surgeons in 10 separate hospitals required entry. As well as providing for surgical audit, the database has been integral to the writing of 130 published articles and articles in press on the topic of thyroid, parathyroid and adrenal surgery. The database has been instrumental to significant changes in the practice of endocrine surgery, including introduction of total thyroidectomy for benign bilateral multinodular goitre by this unit two decades ago, leading to changed practice in most countries around the globe. Data acquisition has also allowed documentation of the safety and efficacy of new minimally invasive endocrine procedures such as minimally invasive parathyroidectomy and minimally invasive thyroid surgery. Audit-based research with accumulation of data based on surgical outcomes, that is, evidence-based surgery, remains the fundamental basis of sound surgical practice with the potential to lead important changes in clinical practice.

Surgeon performed ultrasound facilitates minimally invasive parathyroidectomy by the focused lateral mini-incision approach.

BACKGROUND: Minimally invasive parathyroidectomy (MIP) is now widely accepted where a single adenoma can be localized preoperatively. In our unit, MIP is offered once a parathyroid adenoma is localized with a sestamibi (MIBI) scan, with or without a concordant neck ultrasound. The aim of this study was to compare the accuracy of surgeon performed ultrasound (SUS) with radiologist performed ultrasound (RUS) in the localization of a parathyroid adenoma in MIBI-positive primary hyperparathyroidism (PHPT). PATIENTS AND METHODS: This is a prospective study of patients undergoing parathyroidectomy for sporadic primary hyperparathyroidism (PHPT) from April 2005 to October 2006 at the University of Sydney Endocrine Surgical Unit. Patients were then divided into those who underwent preoperative RUS or SUS. RESULTS: Two-hundred eighteen patients formed the study group. One hundred forty-eight (66%) patients had RUS and 87 (39%) had SUS. Overall, RUS correctly localized the parathyroid adenomas in 121 of 148 (82%) patients. Surgeon performed ultrasound correctly localized the abnormal parathyroid adenoma in 72 of 87 (83%) of cases. There was no significant difference in the proportion of patients with single gland disease, double adenomas, or hyperplasia correctly localized by SUS or RUS. Incorrect interpretation of ultrasound imaging was due to cystic degeneration in thyroid nodules, lymph nodes, retro-esophageal location of adenomas and ectopic and small parathyroid glands. CONCLUSIONS: Surgeon performed ultrasound is a useful adjunctive tool to MIBI localization for facilitating MIP and when performed by experienced parathyroid surgeons, it can achieve accuracy rates equivalent to that of a dedicated parathyroid radiologist.