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Stan Sidhu

Publications and source records attributed to Stan Sidhu.

15 recordsLinked to original sources
PubMed2006

Routine ipsilateral level VI lymphadenectomy reduces postoperative thyroglobulin levels in papillary thyroid cancer.

BACKGROUND: Lymphadenectomy in clinically node-negative papillary thyroid cancer (PTC) is controversial. The aim of this study is to determine whether routine ipsilateral level VI lymphadenectomy (LNDVI) has advantages over total thyroidectomy (TT) alone. METHODS: A retrospective cohort study was performed. Patients undergoing surgery for clinically node-negative PTC >1 cm were included. Group A had TT and LNDVI. Group B had TT alone. The number of radioiodine treatments and postablative stimulated serum thyroglobulin (TG) levels were compared. RESULTS: From 1995 to 2005, 447 patients with clinically node-negative PTC underwent surgery. Group A (n = 56) had TT and LNDVI. Group B (n = 391) had TT alone. Tumor size was equivalent (group A, 20 mm; group B, 23 mm; P = .14) as were MACIS (metastasis, age, completeness of resection, invasion, and size) scores (group A, 4.70; confidence interval, 4.23-5.17; group B, 4.73; confidence interval, 4.4-5.05). Serum postablative TG levels were lower in group A (0.4 microg/L) compared with group B (9.3 microg/L), P = .02. More patients had undetectable TG levels in group A (72%) than in group B (43%) (P < .001). Long-term complications rates were the same. CONCLUSIONS: In PTC the addition of routine LNDVI results in lower postablation levels of TG and higher rates of athyroglobulinemia when compared with TT alone.

Adult↗
PubMed2006

Intraoperative parathyroid hormone measurement during minimally invasive parathyroidectomy: does it "value-add" to decision-making?

BACKGROUND: Routine use of intraoperative parathyroid hormone levels (IOPTH) during minimally invasive parathyroidectomy (MIP) has been challenged simply because the test works best when needed least, ie, once a solitary adenoma has been resected, and is less accurate with multiple gland disease. It has also been shown not to be cost-effective. The aim of this study was to determine if IOPTH "value-added" to decision-making during MIP. STUDY DESIGN: The study group comprised 100 consecutive patients with sporadic hyperparathyroidism and an unequivocally positive sestamibi scan who were undergoing MIP in our unit from June 2004 until October 2005, from whom blood was collected for parathyroid hormone measurement preoperatively, preexcision, and at 10 and 30 minutes postremoval. No action was taken on the results of the test. RESULTS: Ninety-eight patients were cured by MIP alone. Two patients had persistent hyperparathyroidism, one of whom was cured with subsequent open reexploration and removal of a second adenoma, and the other remains hypercalcemic despite additional open neck exploration. IOPTH in both patients failed to fall in retrospect, only the first would have been cured by conversion at the time of operation. The value-added accuracy of IOPTH was really only 1%. In an additional nine patients, IOPTH at 10 minutes had failed to fall by > 50% from the highest level, those patients (9%) would have been subjected to an unnecessary conversion on the basis of a false-negative result. CONCLUSIONS: IOPTH does not substantially value-add to decision-making during MIP. Most patients will be cured with appropriate selection for MIP based on preoperative localization studies.

Adult↗
PubMed2004

Adrenocortical cancer: recent clinical and molecular advances.

PURPOSE OF REVIEW: Adrenocortical cancer (ACC) is an uncommon disorder that remains a challenge to the surgeon and oncologist. When the disease is localized to the adrenal gland and readily amenable to surgical resection, reasonable 5-year survival rates are possible. Locally invasive disease carries a poorer prognosis, and metastatic disease is uniformly fatal within 1 year. In this review, we summarize the current knowledge regarding the clinical management of ACC and the molecular mechanisms underlying the disease. RECENT FINDINGS: The clinical manifestations, staging, and current treatment for ACC has been well documented. Surgery is still the mainstay of treatment, but identifying molecular targets for chemotherapeutic agents or monoclonal antibodies would be a great advance. At present, our understanding of pathogenic mechanisms is crude; however, the molecular events regulating this aggressive disease are beginning to emerge, especially in the last few years. The advent of laparoscopic adrenalectomy has also created its own dilemmas regarding the appropriate surgical approach to the large, potentially malignant adrenal mass. SUMMARY: The challenge in the management of this disease lies in understanding the molecular mechanisms that underlie the development of ACC with the diagnostic and therapeutic benefits that would ensue.

Adrenal Cortex Neoplasms↗
PubMed2004

Minimal access thyroid surgery: technique and report of the first 25 cases.

BACKGROUND: Minimal access thyroid surgery, using various techniques, is increasingly being reported. The present study reviews our experience with thyroid surgery using a lateral focused mini-incision approach, and assesses its safety and feasibility. METHODS: The study group comprised all patients undergoing minimal access thyroid surgery (MATS) during the period May 2002-May 2003. Data were prospectively gathered, including patient demographics, indication for surgery, operation performed, nodule size, final pathology, and complications. Exclusion criteria for this procedure included: family history of thyroid cancer, previous neck irradiation or surgery, carcinoma on fine needle aspiration, presence of significant thyroiditis, multinodular goitre, and nodule size >3 cm. The operation was carried out through a 2.5-cm lateral incision placed directly over the nodule, with exposure gained by dissecting the plane between the sternomastoid muscle and the lateral edge of the strap muscles. RESULTS: Twenty-five patients underwent MATS, 22 women and three men. Nineteen patients underwent hemithyroidectomy, five underwent isthmectomy, and one underwent local nodule excision. The average measured incision size was 2.63 cm at the end of the procedure. The average nodule size was 2.2 cm, and the average thyroid lobe resected measured 4.7 cm in maximal length. Final pathology revealed benign nodules in 21 patients and four thyroid cancers (two follicular and two papillary). There was one wound infection and two patients had temporary recurrent laryngeal nerve neuropraxia. CONCLUSION: Minimal access thyroid surgery is a safe and feasible alternative to open thyroid surgery in selected cases.

Female↗
PubMed2004

Horner's syndrome in association with thyroid and parathyroid disease.

BACKGROUND: Injury to the cervical sympathetic chain and its consequence, Horner's syndrome, as a result of thyroid pathology or surgical intervention is an uncommon complication. The purpose of the present study was to examine the experience of one endocrine surgical unit with pre and postoperative Horner's syndrome. METHODS: This is a retrospective case series. The study group comprised all patients undergoing thyroid and parathyroid surgery at Royal North Shore Hospital from January 2000 to October 2003 who were identified as having either pre or postoperative Horner's syndrome. Patient demographics, operation performed, underlying pathology and outcomes were evaluated. RESULTS: There were nine cases of Horner's syndrome recorded from a total of 2208 thyroid and parathyroid operations undertaken: three with preoperative Horner's, an incidence of 0.14%, six with postoperative Horner's, an incidence of 0.27%. Patients ranged in age from 22 to 87 years. Two of the three preoperative cases were related to benign pathology, the remaining case having anaplastic carcinoma. Five of the six postoperative cases were related to thyroid malignancy with lymph node dissection; one case was associated with benign parathyroid pathology. CONCLUSIONS: Cervical sympathetic chain injury is a rare complication of surgery for thyroid and parathyroid conditions. The presence of preoperative Horner's does not necessarily indicate an underlying malignancy.

Adult↗
PubMed2003

Clinical and molecular aspects of adrenocortical tumourigenesis.

Adrenal masses are a common problem affecting 3-7% of the population. The majority turn out to be benign adrenocortical adenomas, which may be functional or non-functional. Much more rarely, these masses represent a primary adrenal carcinoma. It is becoming increasingly recognized that of the benign functioning adenomas or hyperplasias, the majority will hypersecrete aldosterone and this will be more frequently detected when hypertensive populations are screened for this disease. In contrast, the incidence of primary adrenocortical carcinoma has remained steady and for this disease, surgery represents the mainstay of treatment. The advent of laparoscopic adrenal surgery has lowered the threshold size for recommending surgery for asymptomatic adrenal masses and as such, an increased proportion of adrenocortical cancers are being resected and detected at an earlier stage. Recent progress has been made in our understanding of the key genetic changes which underpin the biology of this disease. Progression from adrenal adenoma to carcinoma involves a monoclonal proliferation of cells which, among other defects, have undergone chromosomal duplication at the 11p15.5 locus leading to overexpression of the IGF2 gene and abrogation of expression of the CDKN1C and H19 genes. TP53 is involved in progression to carcinoma in a subset of patients and the frequency of ACTH receptor deletion needs to be more fully explored. Other key oncogenes and tumour suppressor genes remain to be identified although the chromosomal loci in which they lie can be identified at 17p, 1p, 2p16 and 11q13 for tumour suppressor genes and chromosomes 4, 5 and 12 for oncogenes.

Adrenal Cortex Neoplasms↗
PubMed2003

A case report in favor of a multistep adrenocortical tumorigenesis.

The mechanisms of adrenocortical tumorigenesis are still not fully understood. Data from clonal analysis, comparative genomic hybridization, and allelotyping suggest that it involves a multistep process during which several genetic defects are progressively acquired, leading to the malignant transformation. The events involved in the first steps of this process are not well known, and most of the abnormalities described in adrenocortical tumors to date are associated with the malignant phenotype. We report a case that suggests that adrenocortical tumorigenesis may be a multistep process. A 43-yr-old patient underwent surgery for an incidentally discovered adrenal mass. Pathological analysis showed that this tumor consisted of two parts: a central part with features of malignancy surrounded by another part with a strictly benign appearance. These data were confirmed by molecular analysis and comparative genomic hybridization that were consistent with either a malignant or benign presentation. The apparently malignant part of the tumor exhibited molecular abnormalities [17p13 loss of heterozygosity (LOH), 11p15 uniparental disomy and overexpression of the IGF-II gene] as well as chromosomal gains and losses (comparative genomic hybridization) that have been previously described in malignant tumors. No abnormalities were found in the surrounding benign tissues. Although this observation is not definitive proof that adrenocortical tumorigenesis occurs via a multistep process, it suggests that there is a progressive change from the benign to the malignant state in some adrenocortical tumors.

Adrenal Cortex Neoplasms↗
PubMed2002

Optimal position for a cervical collar incision: a prospective study.

BACKGROUND: The descriptions of the optimal method for placing a cervical collar incision for thyroidectomy or parathyroidectomy are varied. It has been our impression that a collar incision marked in the neutral upright neck, migrates superiorly relative to the sternal notch when the patient is placed in the supine position. The aim of this study was to investigate the validity of this impression and to assess whether this is influenced by patient factors and/or pathology. METHODS: Fifty patients undergoing either thyroid or parathyroid surgery had a planned incision marked 1 finger-breadth (17 mm) above the sternal notch when sitting in the upright position. When placed in the supine position, with neck extended, the distance from the sternal notch to the marked incision was remeasured. Patient variables such as body mass index, height, weight and neck circumference were documented prospectively and data were recorded on operative details and tumour pathology. RESULTS: The collar incision marked in the neutral upright neck, migrated on average 21 mm superiorly once the patient was placed supine with the neck extended (P=0. 0001 ).The extent of migration was independent of all patient factors, type of operation and thyroid or parathyroid pathology. CONCLUSIONS: Migration of a proposed cervical collar incision does occur. An inappropriately placed incision may lead to excessive scarring if it is too low, or unusual prominence if it is too high. We believe a good position for marking such an incision is 1 fingerbreadth above the sternal notch with the patient in a neutral, upright position.

Cicatrix↗
PubMed2002

Laparoscopic adrenalectomy: a 6-year experience of 59 cases.

BACKGROUND: The aims of this paper were to review our experience with laparoscopic transperitoneal adrenalectomy, report on outcomes in comparison with the published literature, and demonstrate any learning curve with the technique. METHODS: A review of our database and patient records was carried out for the period April 1995 to December 2000. Patient demographics, tumour characteristics, operating times, outcomes and lengths of stay were studied. Diagnostic tools, including a comparison between tumour size on computed tomography scanning and on pathological section were reviewed. A comprehensive literature review was conducted using MEDLINE. RESULTS: Indications for surgery included 33 patients with primary hyperaldosteronism (29 adenomas, 4 hyperplasias), 12 phaeochromo-cytomas, 7 cortisol-secreting adenomas, 4 non-secreting adenomas, 1 medullary cyst, 1 metastasis and 1 ganglioneuroma. The tumours ranged in size from 7 to 110 mm. All tumours were localized and lateralized preoperatively using standard techniques. Throughout the review period, six open procedures were undertaken electively, for various reasons. Three cases were converted to open procedures (5.1%). Thirty-eight left and 21 right procedures were undertaken. For all laparoscopic procedures, the average time in the operating theatre was 175.1 min. Men took 188.3 min compared with 165.7 min for women. Left-sided lesions took 178.72 min compared with 167.63 min for right-sided lesions. The average length of stay was 3.8 days. There was one wound infection, one blood transfusion and two readmissions: one for pain control in a patient with difficult home circumstances, and one patient suffered transient hypoadrenalism. CONCLUSION: The results achieved in our initial experience with this technique are comparable with the published literature. The results confirm that laparoscopic adrenalectomy is the method of choice for resection of benign adrenal pathology. The procedure has a learning curve and should be performed by a surgeon experienced in both open and laparoscopic adrenal surgery.

Adrenal Gland Diseases↗
PubMed2002

Changing pattern of adrenalectomy at a tertiary referral centre 1970-2000.

BACKGROUND: In 1987, a report from this unit described the changing indications for open adrenalectomy over a 15-year period. The indications for adrenalectomy had switched from it being the principal therapeutic procedure used in advanced breast cancer in the early 1970s, to being predominately performed for Cushing's disease or incidental, asymptomatic, adrenal masses by the early 1980s. The aim of the present study was to evaluate the changes in the presentation and management of adrenal disease in the last 15 years and to compare these findings with our previously published results. METHODS: Information was gathered from a prospective database of all patients undergoing adrenalectomy in the University of Sydney Endocrine Surgical Unit at Royal North Shore Hospital from 1 January 1987 to 31 December 2000. Information was obtained on patient presentation, diagnostic investigations, indications for surgery, procedure performed and surgical outcomes. Prior to 1987, information was gathered by retrospective review of case notes of patients who had undergone adrenalectomy at Royal North Shore Hospital. During the period from 1 January 1970 to 31 December 2000, 236 patients underwent adrenalectomy. Excluding the 68 adrenalectomies performed for breast cancer, left 168 patients who underwent adrenalectomy for functional or non--functional masses. There were 97 (58%) women and 71 (42%) men, with a mean age of 48 years. RESULTS: Of the 168 patients, the principal indications for surgery were hyperaldosteronism (32%), phaeochromocytoma (20%), hypercortisolism (20%), incidentaloma (16%), carcinoma (6%) and other reasons (6%). Examination of the number of cases in each pathological group for the periods 1970-1986 and 1987-2000, revealed an 8-fold increase in the number of operations for hyper-aldosteronism, and a 3-fold increase in cases of phaeochromocytoma. The number of operations for the other pathological groups remained steady. The annual incidence of adrenalectomy in the hospital has steadily risen since 1990, with a linear increase in the adrenalectomy rate since the introduction of laparoscopic adrenalectomy in 1995. There were fewer complications in either the open or laparoscopic group since 1987 compared with the pre-1987 cohort. CONCLUSIONS: In the past 5 years, there has been a linear increase in the number of adrenalectomies performed in this unit for hyperaldosteronism and to a lesser extent phaeochromocytoma. This is a reflection of increased clinical awareness, improved diagnostic modalities and the advent of laparoscopic adrenalectomy.

Adrenal Gland Diseases↗
PubMed2002

Minimal access thyroid surgery: is it feasible, is it appropriate?

BACKGROUND: Reports of minimal access thyroid surgery (MATS) using various techniques have recently appeared. This study examined the feasibility of MATS using either a lateral 'focused' or endoscopically assisted approach. METHODS: The study group comprised all patients undergoing minimally invasive parathyroidectomy (MIP) during the period May 1998 to April 2002 in whom a concomitant thyroid procedure was undertaken. All procedures were performed either through a 2-cm lateral cervical incision (n = 19) or endoscopically (n = 7). RESULTS: Twenty-six patients underwent thyroid surgery, consisting of either local excision of a thyroid nodule (n = 25) or hemi-thyroidectomy (n = 1). In 13 patients the nodule was incidentally discovered, in four patients removal of the parathyroid necessitated partial thyroidectomy, and in nine patients the lesion identified by preoperative parathyroid localization proved to be a thyroid nodule. There were no permanent complications in the study group. Two patients required drainage of a haematoma. The final pathology of all 26 cases revealed benign nodular thyroid disease. CONCLUSION: Thyroid surgery can safely be performed as a minimally invasive procedure. Minimal access thyroid surgery is therefore a feasible option for selected patients. The question remains to be answered as to whether this surgical approach is appropriate treatment for nodular thyroid disease.

Adult↗
PubMed2002

Comparative genomic hybridization analysis of adrenocortical tumors.

Comparative genomic hybridization (CGH) is a molecular cytogenetic technique that allows the entire genome of a tumor to be surveyed for gains and losses of DNA copy sequences. A limited number of studies reporting the use of this technique in adult adrenocortical tumors have yielded conflicting results. In this study we performed CGH analysis on 13 malignant, 18 benign, and 1 tumor of indeterminate malignant potential with the aim of identifying genetic loci consistently implicated in the development and progression of adrenocortical tumors. Tissue samples from 32 patients with histologically proven adrenocortical tumors were available for CGH analysis. CGH changes were seen in all cancers, 11 of 18 (61%) adenomas, and the 1 tumor of indeterminate malignant potential. Of the adrenal cancers, the most common gains were seen on chromosomes 5 (46%), 12 (38%), 19 (31%), and 4 (31%). Losses were most frequently seen at 1p (62%), 17p (54%), 22 (38%), 2q (31%), and 11q (31%). Of the benign adenomas, the most common change was gain of 4q (22%). Mann-Whitney analysis showed a highly significant difference between the cancer group (mean changes, 7.6) and the adenoma group (mean changes, 1.1) for the number of observed CGH changes (P < 0.01). Logistic regression analysis showed that the number of CGH changes was highly predictive of tumor type (P < 0.01). This study has identified several chromosomal loci implicated in adrenocortical tumorigenesis. Activation of a protooncogene(s) on chromosome 4 may be an early event, with progression from adenoma to carcinoma involving activation of oncogenes on chromosomes 5 and 12 and inactivation of tumor suppressor genes on chromosome arms 1p and 17p.

Adenoma↗