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Peter Angelos

Publications and source records attributed to Peter Angelos.

At least 19 recordsLinked to original sources
PubMed2006

What is the link between nonlocalizing sestamibi scans, multigland disease, and persistent hypercalcemia? A study of 401 consecutive patients undergoing parathyroidectomy.

BACKGROUND: We hypothesized that nonlocalizing sestamibi scans would correlate with multigland disease and persistent primary hyperparathyroidism. METHODS: We reviewed records for 401 consecutive patients who underwent parathyroidectomy from 1999 to 2004. Gender, age, preoperative imaging, surgical findings, gland weight and volume, and 6-month calcium levels (Ca) were examined. RESULTS: We identified 289 women and 112 men, 297 of whom had a preoperative sestamibi scan localized to a single gland (localized group; LG). Ninety-six percent of the LG were found to have single-gland disease, and 4% had multigland disease (MGD). In the nonlocalized group (NLG), 76% had single-gland disease and 24% MGD. Mean gland weight was greater in the LG than in the NLG (1128 mg vs 699 mg; P < .05). Mean gland volume was larger in the LG (1.34 cc vs 0.89 cc; P < .05). A localizing sestamibi scan had a positive predictive value (PPV) of 96% and a likelihood ratio of 2.29 for predicting "curative" intraoperative parathyroid hormone drop after removal of a single abnormal gland. Patients were stratified into normocalcemic (NCa) and hypercalcemic (HCa) groups based on 6-month postoperative serum calcium data (n = 328). HCa incidence at 6 months did not differ significantly between the LG (5%) and NLG (3%). A localizing scan had a PPV of 95% for normocalcemia at 6 months. A nonlocalizing scan had a PPV of 21% for HCa at 6 months. CONCLUSIONS: Nonlocalizing sestamibi scans were more common in primary hyperparathyroidism with MGD and were associated with smaller-volume abnormal glands found at operation. Preoperative sestamibi scan-results did not predict HCa at 6 months.

Adenoma↗
PubMed2006

Minimally invasive video-assisted thyroidectomy for follicular neoplasm: is there an advantage over conventional thyroidectomy?

BACKGROUND: Minimally invasive video-assisted thyroidectomy (MIVAT) is safe and effective for selected patients, but its advantages are not clearly defined. Results of MIVAT for follicular neoplasms at a single institution were retrospectively evaluated to define its advantages or disadvantages. METHODS: Between October 2002 and May 2004, 22 patients underwent MIVAT. Twenty-six patients who underwent conventional thyroidectomy during the same time period served as matched controls. Operative times, pathologic findings, complications, analgesic requirements, and incision lengths were retrospectively evaluated. RESULTS: Four MIVAT and three conventional surgery patients underwent total thyroidectomy. Eighteen MIVAT and 23 conventional patients underwent hemithyroidectomy. The operative time (mean +/- SEM) for hemithyroidectomy was 102 +/- 4 minutes for MIVAT and 86 +/- 3 minutes for conventional surgery (P < .05). In subgroup analysis that excluded patients with thyroiditis, operative times were not significantly different: MIVAT, 99 +/- 4 minutes; conventional, 88 +/- 4 minutes. The mean incision length was 2.3 +/- .5 cm in the MIVAT group. Conventional thyroidectomy was performed through a 4- to 5-cm incision. The average amount of narcotic used was not significantly different (intravenous, 9.9 +/- 3.1 mg [MIVAT] vs. 12.4 +/- 3.8 mg; oral, 10.3 +/- 4.2 mg [MIVAT] vs. 3.5 +/- 2.0 mg). The conventional group received more cyclooxygenase 2 inhibitor (527 +/- 9 mg vs. 187 +/- 84 mg; P < .05). One patient in each group experienced transient hoarseness. There were no cases of permanent hypoparathyroidism or recurrent laryngeal nerve injury in either group. CONCLUSIONS: MIVAT is as safe and effective as conventional thyroidectomy and is associated with similar narcotic analgesic requirements, but it can be performed through smaller incisions. Operative times were significantly longer for MIVAT, but when patients with thyroiditis were excluded, operative times were not significantly different.

Adenocarcinoma, Follicular↗
PubMed2006

Which intraoperative parathyroid hormone assay criterion best predicts operative success? A study of 352 consecutive patients.

HYPOTHESIS: The 6 published criteria for predicting curative parathyroid resection by means of intraoperative parathyroid hormone (IOPTH) assay are not equivalent. DESIGN: Retrospective review of 352 patients undergoing parathyroidectomy for primary hyperparathyroidism from January 1, 1999, to December 31, 2004. We evaluated 6-month postoperative IOPTH values and serum calcium levels. SETTING: Tertiary referral center. MAIN OUTCOME MEASURES: The IOPTH values at baseline (preincision and preexcision) and at 5 and 10 minutes after parathyroidectomy were reviewed according to the Miami criterion (>50% drop from highest baseline IOPTH level at 10 minutes after excision), criterion 1 (>50% drop from preincision IOPTH level at 10 minutes), criterion 2 (>50% drop from highest baseline IOPTH level at 10 minutes and final IOPTH level within the reference range), criterion 3 (>50% drop from highest baseline IOPTH level at 10 minutes and final IOPTH level less than the preincision value), criterion 4 (>50% drop from highest baseline IOPTH level at 5 minutes), and criterion 5 (>50% drop from preexcision IOPTH level at 10 minutes). RESULTS: Criterion 2 had sensitivity of 88%, specificity of 22%, positive predictive value of 97%, and negative predictive value of 6%. Criterion 2 had good agreement with criteria 1 and 3. Of patients whose IOPTH level drop satisfied criterion 2 but not criterion 1, 14% had postoperative hypercalcemia at 6 months. When criterion 2 was not satisfied but criteria 1, 3, 4, and 5 and the Miami criterion were, failure rates were 0%, 4%, 7%, 6%, and 9%, respectively. CONCLUSIONS: Satisfying criterion 2 had a high operative success but resulted in additional unnecessary surgical exploration. Criterion 1 was better at predicting postoperative normocalcemia than criterion 2.

Biomarkers↗
PubMed2006

Identification and treatment of aggressive thyroid cancers. Part 1: subtypes.

Most thyroid cancers are slow-growing, easily treatable tumors with an excellent prognosis after surgical resection and targeted medical therapy. Unfortunately, 10% to 15% of thyroid cancers exhibit aggressive behavior and do not follow an indolent course. Approximately one-third of patients with differentiated thyroid cancers will have tumor recurrences. Distant metastases are present in about 20% of patients with recurrent cancer. Approximately half of patients with distant metastases die within 5 years. The loss of the ability to concentrate radioiodine and produce thyroglobulin is a sign of dedifferentiation, which occurs in about 30% of patients with persistent or recurrent thyroid cancer. Dedifferentiation is associated with poorer responses to conventional therapy and difficulty monitoring tumor burden. Clinicians must identify tumors with more aggressive biology and treat them accordingly with more aggressive regimens. Part 1 of this two-part article describes in detail the distinct types of thyroid cancer, as well as risk factors, outcomes, and prognostic factors, with a focus on thyroid cancers of follicular cell origin. Part 2, which will appear in next month's issue, covers risk assessment and staging, findings that suggest the presence of aggressive tumors, recurrent/metastatic disease, and the value of treatment with chemotherapy and external-beam radiotherapy. Experimental treatments utilizing molecular targets, redifferentiation agents, and gene therapy are covered briefly as well.

Antineoplastic Agents↗
PubMed2006

Identification and treatment of aggressive thyroid cancers. Part 2: risk assessment and treatment.

Most thyroid cancers are slow-growing, easily treatable tumors with an excellent prognosis after surgical resection and targeted medical therapy. Unfortunately, 10% to 15% of thyroid cancers exhibit aggressive behavior and do not follow an indolent course. Approximately one-third of patients with differentiated thyroid cancers will have tumor recurrences. Distant metastases are present in about 20% of patients with recurrent cancer. Approximately half of patients with distant metastases die within 5 years. The loss of the ability to concentrate radio-iodine and produce thyroglobulin is a sign of dedifferentiation, which occurs in about 30% of patients with persistent or recurrent thyroid cancer. Dedifferentiation is associated with poorer responses to conventional therapy and difficulty monitoring tumor burden. Clinicians must identify tumors with more aggressive biology and treat them accordingly with more aggressive regimens. Part 1 of this two-part article, which appeared in March, described in detail the distinct types of thyroid cancer, as well as risk factors, outcomes, treatment, and prognostic factors, with a focus on thyroid cancers of follicular cell origin. Part 2 covers risk assessment and staging, findings that suggest the presence of aggressive tumors, recurrent/metastatic disease, and treatment with chemotherapy and external-beam radiotherapy. Experimental treatments utilizing molecular targets, redifferentiation agents, and gene therapy are covered briefly as well.

Antibodies, Monoclonal↗
PubMed2005

Six core competencies and seven deadly sins: a virtues-based approach to the new guidelines for graduate medical education.

As part of efforts afoot to improve the overall quality of physician training, the Accreditation Council for Graduate Medical Education (ACGME) has endorsed a set of competencies that will be the blueprint for outcomes-based graduate medical education for years to come. While the spirit of this new law is taking shape, the letter remains largely unwritten. To bridge this gap, administrators of programs from all specialties must determine how the core competencies will be taught, evaluated, modeled, and enforced within their respective programs. This paper summarizes these challenges, in particular for surgical programs, and focuses constructively on the modeling/enforcement approach, describing key characteristics that programs should pursue and cultivate (virtues) as well as the signal prohibitions (vices) that both trainees and trainers must avoid. Regardless of specialty or programmatic particulars, virtues and vices may be used to define a context in which general competencies may be understood, and yield operational guidance upon which ultimate discussions of evaluation, remediation, and graduation may be predicated.

Education, Medical, Graduate↗
PubMed2005

Compliance with HIPAA regulations: ethics and excesses.

HIPAA regulations have been seen by many physicians as providing innumerable administrative hoops that require jumping through with no clear benefit for individual patients. Although this article has not comprehensively explored the requirements of HIPAA regulations, it has focused on the issues of "incidental disclosures" that are so important to the daily interactions of physicians and patients. Through the use of illustrative cases, it has been shown that HIPAA regulations frequently are based on well-accepted ethical principles. Although one should never conclude that changing something from an ethical responsibility to a legal responsibility makes it more important, there is no question that HIPAA regulations have forced physicians to consider more carefully how confidential information may be transmitted to others. As such, physicians should look on HIPAA regulations as largely supporting the use of professional judgment in providing good quality medical care. Although not all aspects of HIPAA are grounded in ethical practices, the overall thrust of the HIPAA regulations is consistent with the ethical practice of medicine and surgery. As a result of this general alignment of the legal and ethical requirements, more attention should be directed by physicians at using good judgment in deciding how to disclose private information, rather than adopting an unreasonable approach that confidentiality may never be breached. As Lo and colleagues have very appropriately pointed out: In the context of inadvertent disclosure, the legal risks of good practice are very low. Physicians should work with risk managers and practice administrators to develop policies that promote good communication in patient care, while taking appropriate steps to protect patient privacy. By adopting such an approach to HIPAA, physicians can abide by the regulations while maintaining high ethical standards and minimizing the impact of the new requirements on physician-patient relationships.

Ethics, Clinical↗
PubMed2005

Thyroid carcinoma.

Explore the source record for details and available documents.

Biomarkers, Tumor↗
PubMed2004

Advance directive use among patients undergoing high-risk operations.

BACKGROUND: The Patient Self-Determination Act requires that patients entering hospitals be asked if they have an advance directive. This has led to increased awareness of advance directives, yet surgeons have paid little attention to their use among patients undergoing even major surgery. We sought to evaluate the use of advance directives in patients undergoing pancreaticoduodenectomy and esophagectomy. METHODS: Patients undergoing these operations between 1996 and 2001 at a university teaching hospital were identified and reviewed for statement of advance directive, its presence in the chart, and impact on patient care. RESULTS: A total of 252 patients met inclusion criteria. The number of patients with an advance directive increased, but had little impact on patient care. CONCLUSIONS: More patients having major surgery have advance directives, but the number present in the medical record remains low. Further attention to advance directives would foster increased communication between surgeons and patients and extend patient autonomy.

Advance Directives↗
PubMed2004

Is there a role for living donor intestine transplants?

The use of living donors with intestinal transplantation is controversial because it may not significantly improve candidate access to organs when intestine-only grafts are needed, and may involve excessive donor risk when combined liver-intestine grafts are required. Although limited data are available for comparison at this time, graft and patient survival rates for intestinal transplantations using living donors are no different than for deceased donor transplantations. Potential benefits that may be provided to the intestine transplant recipient through the use of living donors include better HLA matching, shorter ischemia times, better bowel preparation, and better opportunities for introducing immunomodulatory strategies. Conversely, living intestine donors are at risk for mortality, significant morbidity, financial loss, and psychologic trauma. The long-term outcomes of living intestine donors have not yet been reported. Ultimately, these data are essential before the wider use of living donors can be advocated for intestinal transplantation.

Ethics, Medical↗
PubMed2002

CT scan in the management of acute appendicitis.

BACKGROUND: Recent studies demonstrate a 98% accuracy of a CT scan in the diagnosis of acute appendicitis. We aimed to determine the accuracy and clinical value of CT scans in patients suspected of having acute appendicitis. PATIENTS AND MATERIALS: We reviewed outcomes of 125 patients over a 5-month period who had CT scans for the initial diagnosis of acute appendicitis. CT scan interpretations were correlated with surgical and pathologic findings. Follow-up was attempted in all patients who did not undergo appendectomy. RESULTS: CT scans and clinical courses were complete in 110 patients (88%); 14 patients were lost to follow-up and 1 was excluded. One patient had two CT scans. Thus, there were 111 CT scans available for review. Radiologic interpretation of these CT scans yielded 36 positive (33%), 67 negative (60%), and 8 indeterminate (7%), resulting in a sensitivity of 90%, a specificity of 89%, a PPV of 78%, and a NPV of 96%. CONCLUSIONS: CT scan may be useful in the diagnosis of acute appendicitis, but the reported high accuracy rate was not reproduced at our institution. CT scan was not clinically useful in 21% of patients. We conclude that a CT scan may be beneficial in the diagnosis of appendicitis with selected patients who have equivocal findings. Thus, at our institution, the accuracy of a CT scan does not justify its routine use in patients with clinical findings of appendicitis.

Adolescent↗
PubMed2002

Palliative thyroidectomy for malignant lymphoma of the thyroid.

BACKGROUND: Current treatment of malignant lymphoma of the thyroid consists of chemotherapy and external beam radiation. The diagnosis can routinely be made by fine-needle aspiration, obviating the need for surgery. However, a significant number of patients present with symptoms of obstruction, necessitating thyroidectomy for palliation. METHODS: To determine the outcomes of patients with malignant thyroid lymphoma after palliative thyroidectomy, we reviewed our experience. Between 1980 and 2001, 27 patients with thyroid lymphoma and symptoms or signs of airway and/or esophageal obstruction were evaluated at 1 of 3 academic institutions. RESULTS: The mean age of the patients was 66 +/- 3 years, and the majority was female. Patients presented with symptoms of dyspnea/stridor (30%), dysphagia/pain (30%), or impending airway obstruction (40%). All underwent palliative surgery. In addition to surgery, 10 patients had combined chemo- and radiotherapy, 10 had radiotherapy alone, and 4 had only chemotherapy. Symptom-free survival after palliative surgery was determined by Kaplan-Meier analysis. The mean actuarial symptom-free survival of patients with symptomatic, malignant thyroid lymphoma was 10 years (95% confidence interval, 7.67 to 12.33 years). CONCLUSIONS: Patients with malignant lymphoma of the thyroid can present with obstructive symptoms requiring palliative intervention. In this group of patients, thyroidectomy can be associated with good long-term palliation and low morbidity.

Aged↗
PubMed2002

Contemporary surgical management of pheochromocytoma.

BACKGROUND: The availability of laparoscopic adrenalectomy led us to review our experience and management of adrenal and extraadrenal pheochromocytoma. METHODS: Seventeen patients undergoing pheochromocytoma resection from January 1997 to August 2001 were categorized as open, laparoscopic, or laparoscopic assisted depending on the surgical approach. Hospital records were reviewed. RESULTS: There was no significant difference between the groups in patient age, weight or preoperative blockade. Operative times for open, laparoscopic, and laparoscopic assisted adrenalectomies were 202, 218, and 260 minutes, respectively. Estimated blood loss was 562 cc, 187 cc, and 925 cc. The average hospital length of stay was 6.2, 3.0, and 5.8 days. CONCLUSIONS: Laparoscopic removal resulted in longer operative times than open, but less operative blood loss and a shorter hospital stay. The laparoscopic assisted approach did not save time nor did it lead to earlier discharge. Laparoscopic adrenalectomy was comparable to the open approach, and is preferential in tumors less than 6 cm. An open approach remains our choice for larger or extraadrenal tumors.

Adrenal Gland Neoplasms↗
PubMed2002

Is preoperative investigation of the thyroid justified in patients undergoing parathyroidectomy for hyperparathyroidism?

BACKGROUND: The finding of coexisting nodular thyroid disease during neck exploration for hyperparathyroidism (HPT) is reported to range from 20%-60%. Thus, the surgeon may encounter a second, unrelated lesion during open parathyroidectomy. Furthermore, with the recent introduction of minimally invasive surgery for HPT, the entire neck may not be explored, and it is important to know the potential risk of missing significant, concurrent thyroid disease. The diagnosis and timely treatment of associated thyroid abnormalities is desirable because a delay in operating would result in increased morbidity associated with a second neck exploration. DESIGN: We examined our 25-year experience at a large tertiary academic medical center, to determine the incidence and type of concurrent thyroid disease seen in patients with HPT. The computerized records of the Department of Pathology, from 1974-1999, were reviewed for patients with primary HPT who underwent surgery. RESULTS: A review of records from 580 patients who underwent surgery for primary HPT showed 103 (18%) patients with concomitant thyroid disease at surgery. All 103 underwent thyroid resection at the time of parathyroidectomy. Thyroid histology showed: 12 (12%): well-differentiated papillary carcinomas, 31 (30%): follicular adenomas, 49 (48%): nodular hyperplasias, 8 (8%): chronic lymphocytic thyroiditis, 1 benign cyst, 1 metastasis, and 1 normal. CONCLUSIONS: Synchronous thyroid disease was found in 18% of primary HPT patients undergoing surgery, and 12% of thyroid lesions were malignant. The overall malignancy rate was 2%. All primary malignancies found were papillary carcinomas, of which 7 of 12 (58%) were microcarcinomas. The significant association of simultaneous pathology in the two glands justifies preoperative thyroid imaging and fine-needle aspiration (FNA) biopsy to determine the best surgical approach for patients with HPT.

Adenoma↗