PubMed Health⌕ Search

Biomedical subjects

L W Delbridge

Publications and source records attributed to L W Delbridge.

At least 19 recordsLinked to original sources
PubMed2006

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.

Carcinoma, Papillary↗
PubMed2003

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.

Adult↗
PubMed2002

Impact of timing on completion thyroidectomy for thyroid cancer.

BACKGROUND: It has been stated that completion thyroidectomy for thyroid malignancy should be performed either within 10 days of the primary operation or after 3 months, to reduce the incidence of complications. The aim of this study was to review the impact of timing on the rate of complications following completion thyroidectomy. METHODS: Data were obtained retrospectively from the Endocrine Surgery Thyroid Data Base, to which the records of all patients have been entered since 1957. The patients who had the last 100 consecutive completion thyroidectomies for thyroid cancer comprised the study group. RESULTS: Sixty-three patients had the second operation performed within 10 days or more than 90 days after the initial operation (group 1). Thirty-seven patients had reoperation between 10 and 90 days after the first procedure (group 2). One patient (2 per cent) in group 1 and one patient (3 per cent) in group 2 suffered a permanent complication (P not significant). CONCLUSION: There was no definite impact of the timing of surgery on the rate of complications after completion thyroidectomy.

Adult↗
PubMed2001

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.

Adult↗
PubMed2001

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.

Adenoma↗
PubMed2001

Incidence and importance of the tubercle of Zuckerkandl in thyroid surgery.

OBJECTIVE: To define the incidence of a distinct tubercle of Zuckerkandl (TZ) and confirm its anatomical relationships with the recurrent laryngeal nerve and the superior parathyroid gland. DESIGN: Two prospective series. SETTING: University teaching hospital, Australia. SUBJECTS: 200 patients who required thyroidectomy. INTERVENTIONS: Anatomical and clinical observations in two series of patients (n = 100 in each). The first defined the incidence of a TZ and preoperative symptoms; the second delineated the relationship of the TZ to the recurrent laryngeal nerve and the superior parathyroid gland. MAIN OUTCOME MEASURES: Anatomical relationships. RESULTS: A TZ was identified in 63% of patients and was > 1 cm in 45%. In 93% of patients with an enlarged TZ, the recurrent laryngeal nerve lay medial to it and the nerve was found lateral to the TZ in 7% of cases. The superior parathyroid gland was usually cranial to the TZ and posterior to the recurrent laryngeal nerve. The size and position of the TZ did not correlate clearly with symptoms. CONCLUSIONS: The TZ is a distinct feature of the thyroid gland that can be recognised during most thyroidectomies. The size and the position of the TZ have no constant relationship to preoperative symptoms. An understanding of the consistent anatomical relationship between the TZ and recurrent laryngeal nerve and superior parathyroid gland is crucial for safe thyroidectomy.

Humans↗
PubMed2001

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.

Adenoma↗
PubMed2001

The value of oblique pinhole images in pre-operative localisation with 99mTc-MIBI for primary hyperparathyroidism.

Technetium-99m labelled 2-methoxyisobutylisonitrile (MIBI) has been extensively utilised for preoperative localisation of parathyroid adenomas. Imaging techniques have varied widely, with many centres not performing routine oblique images; thus this study aimed to examine the value of routine oblique pinhole imaging. Ninety-two patients underwent pre-operative 99mTc-MIBI imaging including early and delayed anterior oblique pinhole images in addition to standard anterior pinhole images and a thyroid study prior to surgery for primary hyperparathyroidism. These studies were reviewed blindly comparing anterior and oblique images and anterior images only in relation to surgical findings. Of the 92 patients, 83 were found to have 86 parathyroid adenomas or parathyroid adenoma/hyperplasia at surgery. When compared to anterior images only, oblique views improved overall sensitivity from 76% to 88% (P<0.05), correctly localised 11 more adenomas than anterior images alone (13%) and improved the confidence of interpretation in 17 patients (20%). In conclusion, routine oblique pinhole views result in greater sensitivity and reporter confidence in pre-operative parathyroid localisation with 99mTc-MIBI.

Adenoma↗