Reoperative surgery for bilateral multinodular goitre in the era of total thyroidectomy.

BACKGROUND: Total thyroidectomy, rather than bilateral subtotal thyroidectomy, is now accepted as the preferred management for bilateral benign multinodular goitre (BMNG) in order to reduce the need for reoperative surgery. The aim of this study was to examine whether this approach has had an impact on presentation for bilateral reoperative thyroid surgery. METHODS: This was a retrospective cohort study. The study group comprised patients presenting with recurrent BMNG who underwent bilateral reoperative thyroid surgery following previous bilateral subtotal or partial thyroidectomy. They were compared with patients undergoing unilateral reoperative thyroid surgery following previous lobectomy, and those undergoing primary total thyroidectomy for BMNG. RESULTS: Between 1 January 1987 and 31 December 2009, 12 354 consecutive thyroid procedures were undertaken. Among those with BMNG, primary total thyroidectomy was undertaken in 3298 patients, unilateral reoperative thyroidectomy in 337 and bilateral reoperative thyroidectomy in 191. Presentations of patients with recurrent BMNG declined gradually over the study period following the change in policy from subtotal to total thyroidectomy; only five patients (representing less than 0.5 per cent of all thyroid surgery) underwent bilateral reoperative surgery for BMNG in the last year of the study. Four of these patients had their initial operation before 1987 and in another unit, whereas the remaining patient initially had surgery overseas. CONCLUSION: The introduction of a policy of initial total thyroidectomy for bilateral BMNG has essentially eliminated the need for bilateral reoperative surgery for recurrent goitre.

Risk of needing completion thyroidectomy for low-risk papillary thyroid cancers treated by lobectomy.

Background: Low-risk differentiated thyroid cancers may, according to the American Thyroid Association (ATA) 2015 guidelines, be managed initially with lobectomy. However, definitive risk categorization requires pathological assessment of the specimen, resulting in completion thyroidectomy being recommended when discordance between preoperative and postoperative staging occurs. This study sought to establish the expected rate of completion thyroidectomy in patients with papillary thyroid cancer (PTC) treated by lobectomy. Methods: Patients with PTC treated over 5 years (2013-2017 inclusive) and meeting the ATA criteria for lobectomy were identified from the prospectively developed database of a high-volume, university department of endocrine surgery. Concordance between the ATA initial and final recommendation, and the putative rate of completion thyroidectomy were calculated. Multivariable analysis was used to assess preoperative factors as predictors of the need for total thyroidectomy. Results: Of 275 patients with PTC who met ATA preoperative criteria for lobectomy there was concordance between this and the final recommendation in 158 (57·5 per cent) and discordance in 117 (43·5 per cent). Most common reasons for discordance were: angioinvasion (30·8 per cent), local invasion (23·9 per cent) or both (20·5 per cent). Four patients (1·5 per cent) had permanent hypoparathyroidism. On multivariable analysis, age, sex, tumour size and family history did not independently predict the final treatment required. Conclusion: Although many patients may be treated adequately with lobectomy, just under half would require completion thyroidectomy. Further work is needed on preoperative risk stratification but, before this, total thyroidectomy remains the treatment of choice for low-risk 1-4-cm PTC in the hands of high-volume thyroid surgeons who can demonstrate low complication rates.

Lymphadenectomy for papillary thyroid cancer: changes in practice over four decades.

AIMS: Lymphadenectomy in the management of papillary thyroid cancer (PTC) has evolved. The aim of this study was to examine the changing role of neck dissection as reflected in the practice of a large thyroid unit over four decades. METHODS: A retrospective cohort study of patients that underwent primary thyroid surgery for papillary cancer in a single unit in the period 1958-2002. Nine 5-year periods were considered and the data relevant to the treatment of the regional lymph nodes reviewed. RESULTS: Nine hundred patients with PTC underwent surgery between 1958 and 2002 of whom 32.7% underwent lymph node dissection (LND). The use of lymphadenectomy increased from 21.4% in 1958-1962 to 48.1% in 1998-2002 of which 84% underwent a selective lymph node dissection (SLND)-a dissection where the LND is determined by the extent of the disease encountered. The mean number of nodes removed during SLND was 12.6 (range 1-56) of which a mean of 3.1 (24.8%) (0-19) were involved by the disease. Cervical levels 6 and level 4 were those most frequently dissected. There was no statistically significant difference in the complication rates in patients undergoing neck dissection and those not. CONCLUSION: The four decade experience reflects a move away from modified radical neck dissection and cherry picking towards SLND. Growing evidence suggests that lymphadenopathy in adult PTC is an adverse prognostic factor. SLND, a lymphadenectomy tailored to the extent of the disease process, is the coherent treatment for PTC since it serves the dual purpose of staging as well as control of local disease. This can be achieved with little morbidity when performed in a specialist centre.

HRPT2 mutations are associated with malignancy in sporadic parathyroid tumours.

BACKGROUND: Hyperparathyroidism is a common endocrinopathy characterised by the formation of parathyroid tumours. In this study, we determine the role of the recently identified gene, HRPT2, in parathyroid tumorigenesis. METHODS: Mutation analysis of HRPT2 was undertaken in 60 parathyroid tumours: five HPT-JT, three FIHP, three MEN 1, one MEN 2A, 25 sporadic adenomas, 17 hyperplastic glands, two lithium associated tumours, and four sporadic carcinomas. Loss of heterozygosity at 1q24-32 was performed on a subset of these tumours. RESULTS: HRPT2 somatic mutations were detected in four of four sporadic parathyroid carcinoma samples, and germline mutations were found in five of five HPT-JT parathyroid tumours (two families) and two parathyroid tumours from one FIHP family. One HPT-JT tumour with germline mutation also harboured a somatic mutation. In total, seven novel and one previously reported mutation were identified. "Two-hits" (double mutations or one mutation and loss of heterozygosity at 1q24-32) affecting HRPT2 were found in two sporadic carcinomas, two HPT-JT-related and two FIHP related tumours. CONCLUSIONS: The results in this study support the role of HRPT2 as a tumour suppressor gene in sporadic parathyroid carcinoma, and provide further evidence for HRPT2 as the causative gene in HPT-JT, and a subset of FIHP. In light of the strong association between mutations of HRPT2 and sporadic parathyroid carcinoma demonstrated in this study, it is hypothesised that HRPT2 mutation is an early event that may lead to parathyroid malignancy and suggest intragenic mutation of HRPT2 as a marker of malignant potential in both familial and sporadic parathyroid tumours.

Epidermal growth factor causes hypocalcemia in sheep.

During iv infusions of epidermal growth factor into sheep, serum calcium concentrations fell, whereas serum magnesium and serum immunoreactive PTH levels increased. Urinary calcium and magnesium decreased significantly. The role of epidermal growth factor in calcium homeostasis is discussed.

RET/PTC and RET tyrosine kinase expression in adult papillary thyroid carcinomas.

The prevalence of RET/PTC rearrangements in papillary thyroid carcinomas (PTCs) varies widely in different studies, and an association of RET/PTC presence with tumor behavior remains to be clarified. A prospective study of 50 adult PTCs examined, using RT-PCR, the prevalence of the 3 main RET rearrangements and also of RET tyrosine kinase (TK) domain sequence expression. The genetic findings were correlated with the MACIS clinical prognostic score and with individual clinical parameters. Three of the patients had been exposed to radiation in childhood or adolescence. Four of the PTCs contained RET/PTC1, confirmed by sequencing, and none contained RET/PTC2 or RET/PTC3. The prevalence of RET rearrangements overall was 8%, but in the subgroup of 3 radiation-exposed patients it was 66.6%. Interestingly, RET tyrosine kinase domain messenger ribonucleic acid was detectable in 70% of PTCs using RET exon 12/13 primers and was detectable in 24% of PTCs using RET exon 15/17 primers. RT-PCR for calcitonin and RET extracellular domain, however, was negative. There was no association between the presence or absence of RET/PTC in the patient's tumor and clinical parameters. We conclude that RET/PTC1 is the predominant rearrangement in PTCs from adults with a history of external irradiation in childhood. RET TK messenger ribonucleic acid expression is common in PTCs, using RT-PCR, and cannot be used to infer the presence of specific RET rearrangements or of RET activation.

Technetium-99m-sestamibi scanning in recurrent medullary thyroid carcinoma.

UNLABELLED: The presence of recurrent medullary thyroid carcinoma (MTC) can be detected early by measurement of serum calcitonin levels, but the localization of recurrent tumors is often difficult. METHODS: We compared 99mTc-sestamibi scans with computed tomographic (CT) scans in 10 patients with recurrent MTC, who had basal serum calcitonin values ranging from 220-61800 ng/liter. Two patients additionally had bone scans performed because of the clinical suspicion of bone metastases. RESULTS: Seven of the 10 patients had at least one site of abnormal 99mTc-sestamibi uptake, and all of these patients had basal serum calcitonin values > 6000 ng/liter. Only five of the 10 patients had abnormal CT scans. Technetium-99m-sestamibi scans detected 22 abnormal sites in the soft tissues of the neck and chest, while CT scans detected only 11 lesions in the neck and chest. Five of these sestamibi positive sites (in the neck and mediastinum of one patient) were confirmed histologically to represent MTC. When imaging the liver, CT scans detected 47 lesions in three patients while 99mTc-sestamibi scans detected none. One of these liver lesions was confirmed as MTC histologically. When imaging bone in two of the patients, the bone scans detected 17 abnormal sites, while 99mTc-sestamibi scans detected six abnormal sites. CONCLUSION: Technetium-99m-sestamibi scans complement CT and bone scans in the localization of recurrent MTC in patients with extremely high calcitonin levels. Technetium-99m-sestamibi scans are more sensitive than CT scans in the assessment of the soft tissues of the neck and chest, but CT is more appropriate for imaging hepatic lesions and bone scans are better for imaging bone lesions. Technetium-99m-sestamibi scans are unlikely to be abnormal in patients with only mild elevation of calcitonin.

Intraoperative quick parathyroid hormone versus same-day parathyroid hormone testing for minimally invasive parathyroidectomy: a cost-effectiveness study.

BACKGROUND: Intraoperative quick parathyroid hormone (QPTH) measurement is claimed to eliminate failures during minimally invasive parathyroidectomy. The cost-effectiveness of QPTH (ie, true cost of avoiding a failed operation) needs careful evaluation. METHODS: In 92 consecutive patients who underwent minimally invasive parathyroidectomy via a small lateral incision, QPTH was estimated preoperatively and at 5, 10, and 15 minutes postparathyroidectomy. QPTH results were subsequently compared with the procedure outcome. Cost-effectiveness analysis was performed for 3 subsequent theoretical management strategies: QPTH not performed, QPTH results available intraoperatively, and parathyroid hormone and serum calcium levels measured routinely with results made available the same day. RESULTS: With criteria for cure being a decrease in the QPTH measurement to less than 50% of preoperative levels and to within normal range, QPTH predictions were true positive in 78 patients; false-negative in 7; false-positive in 1; and true negative in 2. The true cost of using QPTH measurement to avoid a failed operation was 19,801.19 US dollars, with 7 patients undergoing unnecessary conversion. Routine same-day parathyroid hormone and calcium measurements significantly reduced this to 624.73 dollars. Sensitivity analysis with varying cost assumptions demonstrated cost-effectiveness analysis to be robust. CONCLUSIONS: The fact that 97% of patients will be cured regardless of QPTH testing combined with its false-negative rates significantly reduces the cost-effectiveness of the test when compared with same-day parathyroid hormone testing.

Intraoperative parathyroid hormone monitoring fails to detect double parathyroid adenomas: a 2-institution experience.

BACKGROUND: We hypothesized that intraoperative parathyroid hormone monitoring (IOPTH) reliably would detect double parathyroid adenomas. METHODS: This was a retrospective study of 20 patients undergoing conventional parathyroidectomy with resection of exactly 2 abnormal glands. Full exploration was performed regardless of IOPTH values, which were measured after anesthetic induction and 5 and 10 minutes following removal of the first abnormal parathyroid gland. Failure to fall below 50% of baseline value by 10 minutes following resection of the first gland indicated the presence of multiglandular disease. RESULTS: All patients were cured. All excised glands were hypercellular on histology. Mean IOPTH values in 9 of the 20 patients with true negative results (noncurative decrease, another gland present) were 66% +/- 7% at 5 minutes and 83% +/- 15% at 10 minutes. The IOPTH values in 11 of the 20 patients with false positive results (curative decrease, another gland present) were 28% +/- 4% at 5 minutes and 18% +/- 2% at 10 minutes. The false positive rate of IOPTH was 55%. CONCLUSIONS: We found that IOPTH failed to reliably detect the presence of double parathyroid adenomas. These data suggest that caution should be exercised when terminating limited parathyroid exploration based on a curative fall in IOPTH values.

Minimally invasive surgery for primary hyperparathyroidism: systematic review.

HYPOTHESIS: Use of minimally invasive parathyroidectomy techniques, either unilateral or endoscopic, will result in the same or improved safety and efficacy outcomes as those of the bilateral open neck exploration technique in patients with primary hyperparathyroidism. DATA SOURCES: Studies on minimally invasive parathyroid surgery were identified using MEDLINE (January 1984 to August 1998), EMBASE (January 1974 to August 1998), and Current Contents (week 1 of 1993 to week 34 of 1998). The search terms were as follows: ((endoscop* or (minimal* and invasive) or unilateral) and parathyroid). The Cochrane Library was searched from issue 1 of 1966 to issue 3 of 1998, using the search terms "parathyroidectomy or parathyroid resection." STUDY SELECTION: Human studies of patients with primary hyperparathyroidism using unilateral or endoscopic exploration were included. Animal studies describing minimally invasive technique development were also included. A surgeon (R.F.P.) and researcher (W.J.B.) independently assessed the retrieved articles for their inclusion in the review. DATA EXTRACTION: Studies directly comparing the unilateral method with bilateral open neck exploration were used to analyze outcomes. DATA SYNTHESIS: Analysis of data using odds ratios and 95% confidence intervals indicated a tendency to favor the unilateral technique. However, these individual studies generally had large confidence intervals; therefore, preference to the unilateral procedure cannot be espoused with certainty. There is also a selection bias due to the strict enrollment criteria for unilateral surgery. CONCLUSIONS: The proposed role of minimally invasive parathyroid surgery is for patients with primary hyperparathyroidism who have unilateral parathyroid pathological features. To assess the safety and efficacy of minimally invasive techniques, it is suggested that their introduction be monitored as part of a trial in Australia, from which data should be accrued to a register.

Intraoperative decision making in follicular lesions of the thyroid: is tumor size important?

BACKGROUND: Intraoperative decision making in treating follicular lesions of the thyroid remains controversial because there are no reliable preoperative or intraoperative factors predictive of malignancy. This study was undertaken to determine whether lesion size is a reliable factor that can be used to predict a final pathologic diagnosis of follicular carcinoma. STUDY DESIGN: This was a retrospective, case-matched control study. One hundred consecutive patients with follicular carcinoma were matched by gender, age, and date of operation with 100 patients with follicular adenomas. Seventy-nine matched pairs had pure follicular lesions and 21 matched pairs had oxyphilic variants of follicular lesions. After confirming adequate matching, lesion size was compared between groups. RESULTS: Regardless of whether all follicular lesions were analyzed or whether only pure follicular or oxyphilic variant lesions were compared, there was no significant difference in lesion size between the carcinoma and adenoma groups. The mean size of all follicular carcinomas was 31.5 +/- 1.7 mm and the mean size of all follicular adenomas was 30.8 +/- 1.5 mm (p = NS). When the proportions of the carcinoma and adenoma groups were indexed by five different size intervals and compared, there was again no significant difference in any category. CONCLUSIONS: On the basis of this case-matched control study, the size of a follicular lesion cannot be used to predict a final diagnosis of follicular carcinoma and is of no value when making intraoperative decisions about the extent of thyroid resection.

Optimal pinhole techniques for preoperative localization with Tc-99m MIBI for primary hyperparathyroidism.

PURPOSE: Technetium-99m-labeled 2-methoxyisobutylisonitrile (Tc-99m MIBI) has been used extensively to localize parathyroid adenomas before operation. Imaging techniques vary widely, and the aim of this study was to determine the optimal time of delayed imaging and the value of routine correlative pertechnetate thyroid imaging. MATERIALS AND METHODS: In this study, preoperative parathyroid localization was performed using pinhole anterior and oblique images (15 minutes and 2 and 4 hours after injection) with correlative pertechnetate thyroid images. Ninety-seven patients underwent dual- or triple-phase Tc-99m MIBI imaging and correlative pertechnetate thyroid imaging before surgery. Two nuclear medicine physicians blinded to the surgical findings interpreted all available images and various Tc-99m MIBI image combinations at 15 minutes alone; 15 minutes and 2 hours, 15 minutes and 4 hours; and 15 minutes and 2 and 4 hours each with and without correlative pertechnetate thyroid imaging. RESULTS: Ninety parathyroid adenomas were detected in 86 patients. The optimal results were achieved with 15-minute and 2- and 4-hour Tc-99m-MIBI images, with correlative thyroid scans resulting in a sensitivity rate of 88%. Fifteen-minute and 2-hour Tc-99m-MIBI images and correlative thyroid scans and 15-minute and 4-hour Tc-99m MIBI images and correlative thyroid scans produced similar results (sensitivity rate, 86% and 83%, respectively; P = not significant). Compared with all Tc-99m MIBI image combinations alone, the addition of the routine correlative thyroid scan significantly improved sensitivity and also improved reporter confidence in 45% of studies. CONCLUSIONS: Of the pinhole techniques compared, 15-minute and 2-hour Tc-99m MIBI images with correlative thyroid scanning may be the preferred imaging protocol, because this yields results similar to imaging for as long as 4 hours after injection in a shorter, more logistically acceptable imaging time.

The Australian experience with the Bethesda classification system for thyroid fine needle aspiration biopsies.

Fine needle aspiration biopsy (FNAB) is the initial investigation of choice for thyroid nodules. The Bethesda system, which classifies thyroid FNABs into different categories each linked to a risk of malignancy, has been widely adopted. However, the risk of malignancy implied by each Bethesda category is likely to vary due to population characteristics and inconsistency in the application of diagnostic criteria.We present our experience of the Bethesda system in 2076 thyroid nodules from 1410 patients. Categories were as follows: 266 (12.8%) were category 1 (B1) non-diagnostic, 1551 (74.7%) category 2 (B2) benign, 97 (4.7%) category 3 (B3) atypia of uncertain significance, 98 (4.7%) category 4 (B4) suspicious for follicular neoplasm, 16 (0.8%) category 5 (B5) suspicious for malignancy and 48 (2.3%) category 6 (B6) malignant.Surgery was performed on 425 nodules from 315 patients. Malignancy rates in the target nodules were B1 4.2%, B2 0.26%, B3 9.3%, B4 15.3%, B5 79% and B6 100%. Twelve patients with B3 nodules underwent repeat FNAB, with eight reclassified as B2, one as B3, one as B1 and two as B4. An incidental microcarcinoma separate to the target nodule was identified in 11.1%.As applied in our institution, and despite very sparing use of B3 and B5 categories, our audit has demonstrated risks of malignancy broadly in keeping with that predicted. Of note, the risk of malignancy in the clinically indeterminate categories of B1, B3 and B4 were all at the lower ranges of those predicted in the Bethesda atlas and mostly lower than those reported by other studies.

Utilization of a MAB for BRAF(V600E) detection in papillary thyroid carcinoma.

Identification of BRAF(V600E) in thyroid neoplasia may be useful because it is specific for malignancy, connotes a worse prognosis, and is the target of novel therapies currently under investigation. Sanger sequencing is the 'gold standard' for mutation detection but is subject to sampling error and requires resources beyond many diagnostic pathology laboratories. In this study, we compared immunohistochemistry (IHC) using a BRAF(V600E) mutation-specific MAB to Sanger sequencing on DNA from formalin-fixed paraffin-embedded tissue, in a well-characterized cohort of 101 papillary thyroid carcinoma (PTC) patients. For all cases, an IHC result was available; however, five cases failed Sanger sequencing. Of the 96 cases with molecular data, 68 (71%) were BRAF(V600E) positive by IHC and 59 (61%) were BRAF(V600E) positive by sequencing. Eleven cases were discordant. One case was negative by IHC and initially positive by sequencing. Repeat sequencing of that sample and sequencing of a macrodissected sample were negative for BRAF(V600E). Of ten cases positive by IHC but negative by sequencing on whole sections, repeat sequencing on macrodissected tissue confirmed the IHC result in seven cases (suggesting that these were false negatives of sequencing on whole sections). In three cases, repeat sequencing on recut tissue remained negative (including using massive parallel sequencing), but these cases demonstrated relatively low neoplastic cellularity. We conclude that IHC for BRAF(V600E) is more sensitive and specific than Sanger sequencing in the routine diagnostic setting and may represent the new gold standard for detection of BRAF(V600E) mutation in PTC.

Management of follicular thyroid carcinoma should be individualised based on degree of capsular and vascular invasion.

INTRODUCTION: Follicular thyroid carcinoma (FTC) includes a spectrum of neoplasms with varying propensity for metastasis. The aim of this study is to describe outcomes for FTC following multimodality treatment, with particular reference to the degree of capsular and vascular invasion and to recommend a rational management approach based on these characteristics. METHODS: Patients with histologically confirmed FTC were identified from a prospectively maintained database. Details of intervention and long-term outcomes were obtained. Outcomes were compared between patients with minimally invasive follicular carcinoma (MI FTC) without vascular invasion (Group 1); angioinvasive MI FTC (Group 2); and those with widely invasive FTC (Group 3). RESULTS: Between May 1983 and December 2008, 124 patients with FTC were identified. The overall disease-free survival rate was 85% at a median of 40 months follow-up. Disease-free survival was 97%, 81% and 46%, respectively, in Groups 1, 2 and 3, and significantly different between groups (p<0.001). Thirteen patients in this series developed distant metastases including 2 in Group 1 and 6 in Group 2. Only patients <45 years of age with MI FTC and no vascular invasion had 100% disease-free survival. After multivariate linear regression, age (p=0.03) and the presence of vascular invasion (p=0.03) were the most powerful predictors of distant metastasis. CONCLUSIONS: Survival is improved in those with minimally invasive compared with widely invasive FTC. In patients <45 years with MI FTC without vascular invasion, hemithyroidectomy may be adequate treatment. All other patients with FTC should undergo total thyroidectomy and radioactive iodine ablation.

Surgical trends in the management of thyroid lymphoma.

AIMS: To determine the changing trends and current role of surgery for the management of thyroid lymphoma. METHODS: A retrospective review of 50 surgical patients with a final diagnosis of thyroid lymphoma over a 35-year period. RESULTS: All patients presented with an enlarging mass, with half having compressive symptoms on presentation. Two-thirds of patients had co-existent histological features of Hashimoto's thyroiditis. Surgery for patients with thyroid lymphoma peaked in the late 1970s (0.79% of all thyroid operations performed) followed by a significant decline in the 1980s with a current frequency of only 0.16% (p=0.009). A larger number of thyroid resections intended as a curative procedure was performed during the first half of this series compared to the latter half (p=0.05). There was no difference in disease-free survival between patients treated by thyroid resection when compared with an open biopsy (p=0.4875). CONCLUSION: The surgical management of thyroid lymphoma has changed with time. Currently a larger proportion of patients are undergoing surgery in order to achieve a histological diagnosis rather than with therapeutic intent, however, an important role for surgery still exists in the management of a patient with severe airways obstruction.

Laparoscopic surgery is safe for large adrenal lesions.

INTRODUCTION: Laparoscopic adrenalectomy has surpassed open adrenalectomy as the gold standard for excision of benign adrenal lesions. The size threshold for offering laparoscopic adrenalectomy is controversial as the prevalence of adrenocortical carcinoma increases with increasing tumour size. The aim of this paper was to assess the safety of laparoscopic adrenalectomy for large adrenal tumours (tumours > or = 60 mm). METHODS: A retrospective cohort study of patients who underwent adrenalectomy in a single unit during the period 1995-2005 was undertaken. RESULTS: One hundred and seventy patients with 173 tumours were included in this study. Of these, 29 were > or = 60 mm in size, and 16 of these patients underwent laparoscopic adrenalectomy. There were 8 adrenocortical carcinomas in the group with tumours > or = 60 mm in size. Five of these patients underwent an open adrenalectomy, while 2 and 1 patients had laparoscopic and laparoscopic converted to open adrenalectomy respectively. Four of the patients undergoing open adrenalectomy died of their disease while 1 is alive with recurrence 3 years later. The 3 patients who underwent either laparoscopic or laparoscopic converted to open adrenalectomy are alive without evidence of disease after 18 months follow up. CONCLUSION: Our data show that patients with tumours > or = 60 mm with no preoperative or intraoperative evidence of malignancy can undergo laparoscopic adrenalectomy without evidence of recurrence on short term follow up. These findings are concordant with the growing body of literature supporting laparoscopic adrenalectomy for potentially malignant tumours > or = 60 mm in size without preoperative or intraoperative features of malignancy.

Pancreatitis following parathyroid surgery.

While pancreatitis may provide the clue to the diagnosis of hyperparathyroidism preoperatively, the occurrence of pancreatitis following parathyroidectomy is not generally recognized. In this study preoperative and postoperative serum amylase estimations, together with a clinical assessment, were performed on 86 patients undergoing neck exploration for hyperparathyroidism. It was found that postoperative hyperamylasaemia occurred in 35% of the total group, while clinically significant pancreatitis was found in 9% of cases. Pancreatitis was significantly more common when thyroidectomy was performed at the time of parathyroidectomy, occurring in 23% of this group of patients, and may be due to the blunted C-cell response of calcitonin secretion to the induced hypercalcaemia associated with operative manipulation. Careful attention should be paid to postoperative abdominal symptoms, for they may indicate pancreatitis.

Surgeon's approach to the thyroid gland: surgical anatomy and the importance of technique.

The cornerstone of safe and effective thyroid surgery is thorough training in and understanding of thyroid anatomy and pathology. With appropriate techniques, total thyroid lobectomy and total thyroidectomy (which should be considered simply as a bilateral total thyroid lobectomy performed during the same operation) can be undertaken with minimal risk of damage to the recurrent laryngeal nerves, the external branches of the superior laryngeal nerves, and the parathyroid glands. Safe surgery requires a specific operative plan, progressing in a series of logical, orderly, anatomically based steps. Exposure of the thyroid gland is followed by careful dissection of the superior pole, utilizing the avascular plane between the superior pole and the cricothyroid muscle to identify and preserve the external branch of the superior laryngeal nerve. Medial retraction of the gland then allows dissection of the lateral aspect of the thyroid lobe. Protection of the recurrent laryngeal nerves and preservation of the blood supply to the parathyroid glands is best achieved by "capsular dissection," ligating the tertiary branches of the inferior thyroid artery on the gland surface. If a parathyroid gland cannot be preserved or becomes ischemic after dissection of its vascular pedicle, it should be immediately minced and autotransplanted into the ipsilateral sternocleidomastoid muscle. The current evolution of outpatient or short-stay thyroidectomy emphasizes the need to avoid complications by utilizing meticulous surgical technique. Minimally invasive thyroidectomy utilizing endoscopic techniques may also affect the practice of thyroid surgery. Even so, understanding the surgical anatomy of the thyroid gland and its possible variations is paramount to safe and effective surgery.

Endoscopically assisted, minimally invasive parathyroidectomy.

BACKGROUND: Despite the success of open parathyroid exploration, minimally invasive alternatives have been emerging. This study reports an experience with endoscopically assisted, minimally invasive parathyroidectomy and evaluates its current role in patients undergoing surgery for hyperparathyroidism. METHODS: One hundred consecutive patients requiring surgery for hyperparathyroidism were evaluated. Endoscopic parathyroidectomy was offered based on the absence of coexisting nodular thyroid disease, previous neck surgery or irradiation, suspicion of parathyroid hyperplasia, or other anatomical or medical contraindications. Some 24 of 100 patients fulfilled the criteria and underwent endoscopic parathyroidectomy. Unequivocal localization to a single site by a technetium-99m-radiolabelled sestamibi scan allowed removal of the adenoma through a 25-mm suprasternal incision while being guided by a surgical telescope. RESULTS: There were no statistically significant differences in operating time or the mean size of resected adenomas between patients undergoing endoscopic and open parathyroidectomy. Four patients required conversion to an open procedure. Two patients developed temporary recurrent laryngeal nerve paresis and one had persistent hyperparathyroidism. CONCLUSION: Although endoscopic parathyroidectomy is technically feasible, its applicability is limited to a minority of patients undergoing operation for hyperparathyroidism. The potential for higher complication and failure rates makes optimism for the procedure appropriately guarded.