Fausto Palazzo

A multicenter cohort study of total thyroidectomy and routine central lymph node dissection for cN0 papillary thyroid cancer

BACKGROUND The role of routine central lymph node dissection (CLND) for papillary thyroid cancer (PTC) remains controversial. The aim of this study was to evaluate the impact of routine CLND after total thyroidectomy (TTx) in the management of patients with PTC who were clinically node negative at presentation with emphasis on stimulated thyroglobulin (Tg) levels and reoperation rates. METHODS This retrospective, multicenter, cohort study used pooled data from 3 international Endocrine Surgery units in Australia, the United States, and England. All study participants had PTC >1 cm without preoperative evidence of lymph node disease (cN0). Group A patients had TTx alone and group B had TTx with the addition of CLND. RESULTS There were 606 patients included in the study. Group A had 347 patients and group B 259 patients. Stimulated Tg values were lower in group B before initial radioiodine ablation (15.0 vs 6.6 ng/mL; P = .025). There was a trend toward a lower Tg at final follow-up in group B (1.9 vs 7.2 ng/mL; P = .11). The rate of reoperation in the central compartment was lower in group B (1.5 vs 6.1%; P = .004). The number of CLND procedures required to prevent 1 central compartment reoperation was calculated at 20. CONCLUSION The addition of routine CLND in cN0 papillary thyroid carcinoma is associated with lower postoperative Tg levels and reduces the need for reoperation in the central compartment.

18F-FDG Avidity of Pheochromocytomas and Paragangliomas: A New Molecular Imaging Signature?

Our objective was to evaluate 18F-FDG PET uptake in patients with nonmetastatic and metastatic chromaffin-derived tumors. Methods: Twenty-eight consecutive unrelated patients with chromaffin tumors, including 9 patients with genetically determined disease, were studied. A combination of preoperative imaging work-up, surgical findings, and pathologic analyses was used to classify the patients into 2 groups: those with nonmetastatic disease (presumed benign, n = 18) and those with metastatic tumors (n = 10). 18F-FDG PET was performed in all cases. Visual and quantitative analyses were individually graded for each tumor. Somatic mutations of the succinate dehydrogenase subunits B and D and Von-Hippel Lindau genes were also evaluated in 6 benign sporadic tumor samples. Results: All but 2 patients showed significantly increased 18F-FDG uptake on visual analysis. The maximum standardized uptake value (SUVmax) ranged from 1.9 to 42 (mean ± SD, 8.2 ± 9.7; median, 4.6) in nonmetastatic tumors and 2.3 to 29.3 (mean ± SD, 9.7 ± 8.4; median, 7.4) in metastatic tumors. No statistical difference was observed between the groups (P = 0.44), but succinate dehydrogenase–related tumors were notable in being the most 18F-FDG–avid tumors (SUVmax, 42, 29.3, 21, 17, and 5.3). Succinate dehydrogenase and Von-Hippel Lindau–related tumors had a significantly higher SUVmax than did neurofibromatosis type 1 and multiple endocrine neoplasia type 2A syndrome–related tumors (P = 0.02). 18F-FDG PET was superior to 131I-metaiodobenzylguanidine in all metastatic patients but one. By contrast, 18F-FDG PET underestimated the extent of the disease, compared with 6-18F-fluorodopa PET, in 5 patients with metastatic pheochromocytoma. However, succinate dehydrogenase mutations (germline and somatic) and functional dedifferentiation do not adequately explain 18F-FDG uptake since most tumors were highly avid for 18F-FDG. Conclusion: 18F-FDG PET positivity is almost a constant feature of pheochromocytomas and paragangliomas. It may be considered a molecular signature of such tumors, although which aspect of the plethora of molecular changes associated with dedifferentiation, germline genetic defects, or the adaptive response to hypoxia is responsible for this characteristic requires further elucidation.

AUSTRALIAN ENDOCRINE SURGEONS GUIDELINES AES06/01. POSTOPERATIVE PARATHYROID HORMONE MEASUREMENT AND EARLY DISCHARGE AFTER TOTAL THYROIDECTOMY: ANALYSIS OF AUSTRALIAN DATA AND MANAGEMENT RECOMMENDATIONS

Background:  The risk of hypocalcaemia after thyroidectomy has traditionally mandated inpatient monitoring for signs and symptoms as well as frequent measurement of serum calcium levels. In recent years there has been much interest in the published work about the use of intact parathyroid hormone (PTH) to better predict hypocalcaemia after thyroidectomy. Although generally accurate, the use of intact parathyroid hormone in Australia has not become widespread. On behalf of the Australian Endocrine Surgeons an analysis of Australian data on the use of PTH levels to predict hypocalcaemia after thyroidectomy was carried out. The data were analysed with a view to making recommendations about the use of this test in clinical practice and the feasibility of achieving safe early discharge for patients.

Endocrine surgical technique: endoscopic thyroidectomy via the lateral approach

BackgroundMinimal access approaches are increasingly used in endocrine surgery. Several minimal access approaches to the thyroid gland have been described, including a small-incision lateral approach and a video-assisted central approach, but to date no technique has been universally accepted.MethodsBenefiting from the experience of more than 500 endoscopic parathyroidectomies via a lateral neck approach, the authors developed an endoscopic thyroidectomy based on the same approach and principles. Patients with solitary nodules smaller than 3 cm in diameter and no history of neck surgery or irradiation were offered this operation. A detailed description of the surgical technique is provided.ResultsOf the 742 thyroidectomies performed in 2004, 38 (5.1%) were endoscopic thyroidectomies. The mean nodule size was 22-mm (range, 7–47-mm), and the mean operating time was 99 min (range, 64–150-min). In all cases, the recurrent laryngeal nerve was preserved intact, and the superior and inferior parathyroids were identified, respectively, in 36 and 33 of the 38 patients. Two patients required conversion to an open cervicotomy. All patients were discharged the day after surgery.ConclusionsThe described endoscopic lateral approach combines the coherence of the minimal access lateral approach and the benefits of fiberoptic magnification. It is a safe and effective technique in the hands of an appropriately trained surgeon.

Thyroid surgery: postoperative hematoma—prevention and treatment

Background and aimsPostoperative haematoma formation is a fortunately rare but potentially life-threatening complication of thyroid surgery. This paper aims to identify potential aetiological factors, describe surgical techniques and newer haemostatic agents that may be used to minimise the risk of haematoma formation and propose surgical strategies to deal with haematoma formation.Materials and methodsAn extensive literature search as well as own considerable experience in a tertiary referral centre endocrine surgical unit was drawn upon to review this topic.ConclusionsPostoperative haematoma may have a multifactorial aetiology. Numerous manoeuvres and surgical haemostatic agents may be employed to minimise the risk of haematoma formation but are no substitute for meticulous haemostasis. In the event of haematoma formation, early surgical re-intervention is strongly advocated with due care given to at risk structures.

The role of 18F‐FDOPA and 18F‐FDG–PET in the management of malignant and multifocal phaeochromocytomas

Background  18F‐DOPA has emerged as a promising tool in the localization of chromaffin‐tissue‐derived tumours. Interestingly, phaeochromocytomas (PHEO) are also FDG avid.

Limited Value of 18F-F-DOPA PET to Localize Pancreatic Insulin-Secreting Tumors in Adults with Hyperinsulinemic Hypoglycemia

CONTEXT Fluorine-18-L-dihydroxyphenylalanine positron emission tomography (18F-FDOPA PET) imaging is increasingly used in the workup of neuroendocrine tumors. It has been shown to be an accurate tool in the diagnosis of congenital hyperinsulinism, but limited information is available on its value in adult disease. OBJECTIVE, PATIENTS, AND DESIGN: The objective of this study was to review our experience with 18F-FDOPA PET imaging in six consecutive patients with hyperinsulinemic hypoglycemia (HH) (four solitary insulinomas, one diffuse beta-cell hyperplasia, one malignant insulinoma). 18F-FDOPA uptake was also evaluated in 37 patients (43 procedures) without HH or other pancreatic neuroendocrine tumors, which acted as a control group. RESULTS Using visual analysis, 18F-FDOPA-PET proved positive in only one case (a multiple endocrine neoplasia type 1 related insulinoma). In diffuse beta-cell hyperplasia, the pancreatic uptake was similar to controls. In the patient with liver metastases, the extent of disease was underestimated. The pancreatic uptake was not statistically different between controls and hyperinsulinemic patients. The main limitation for identifying insulinomas or beta-cell hyperplasia in adults appears to be to the 18F-FDOPA uptake and retention in the whole pancreas. This drawback is potentially circumvented in focal hyperplasia in newborns due to a lower aromatic amino acid decarboxylase expression in the extralesional pancreatic parenchyma. CONCLUSIONS 18F-FDOPA PET is of limited value in localizing pancreatic insulin secreting tumors in adult HH. Our results contrast with the referential study and require further analysis.

PARATHYROID HORMONE ASSAY PREDICTS HYPOCALCAEMIA AFTER TOTAL THYROIDECTOMY

Background:  Postoperative parathyroid gland function after total thyroidectomy (TT) has traditionally been monitored by the measurement of serum calcium concentrations. The purpose of this study is to determine whether measurement of parathyroid hormone (PTH) concentrations in the early postoperative period accurately predicts patients at risk of developing hypocalcaemia.

Long-term Outcome following Laparoscopic Adrenalectomy for Large Solid Adrenal Cortex Tumors

IntroductionLaparoscopic adrenalectomy (LA) is the procedure of choice for small benign adrenal tumors. In the absence of local invasion or metastases, the preoperative diagnosis of an adrenocortical carcinoma (ACC) is difficult, often leaving size as the principal predictor of malignancy. Large tumors are resectable laparoscopically, but the long-term outcome and therefore appropriateness of LA for cortical tumors > 6 cm is not known.MethodsWe reviewed the LA experience in our institution since its introduction in June 1994. Patients who underwent LA for solid cortical tumors ≥ 60 mm in diameter without preoperative or intraoperative evidence of malignancy were reviewed. Follow-up data, including clinical examination, biochemical analysis, and repeat scans, were reviewed for evidence of local or systemic recurrent disease.ResultsBetween 1994 and 2004 a total of 462 adrenalectomies were performed, 391 of which were done laparoscopically. Among them, 19 were solid cortical tumors ≥ 60 mm in diameter with no overt malignant preoperative or intraoperative characteristics: 9 nonsecreting tumors, 8 Cushing’s syndrome tumors (including 2 virilizing variants), 1 virilizing tumor, and 1 aldosteronoma. The mean age of the patients was 49.9 years (range 22–77 years), and the mean tumor size was 69.0 mm (range 60–80 mm). Histology confirmed a cortical adenoma in eight patients, malignant tumors in three, and indeterminate tumors in eight. The mean follow-up was 34 months (range 4–108 months). Two patients died of systemic recurrent disease (liver metastases) at 10 and 19 months, respectively, following surgery; two other patients died 12 and 21 months, respectively following surgery owing to unrelated cardiovascular and cerebrovascular pathology. One patient underwent surgery for local recurrence 54 months after primary surgery; the remaining 14 patients are well with no clinical or radiologic evidence of recurrent disease.ConclusionsLaparoscopic adrenalectomy for large solid cortical tumors without pre- or intraoperative evidence of malignancy is not contraindicated, and it is unlikely to have a deleterious effect on long-term outcome. Each case should be considered individually. We provide an algorithm for the approach to adrenocortical tumors ≥ 6 cm.

Systematic review and meta-analysis of retroperitoneoscopic versus laparoscopic adrenalectomy†

Laparoscopic adrenalectomy (LA) has replaced open adrenalectomy as the standard operation for non‐malignant adrenal tumours. Retroperitoneoscopic adrenalectomy (RA) is an increasingly popular alternative minimally invasive approach. Advocates of each technique claim its superiority, but the issue has yet to be resolved and conclusions are complicated by the existence of a lateral (LRA) and true posterior (PRA) RA.