Search PubMed⌕ Search

Biomedical subjects

Peter Angelos

Publications and source records attributed to Peter Angelos.

At least 19 recordsLinked to original sources
PubMed2007

Parathyroid cyst: often mistaken for a thyroid cyst.

INTRODUCTION: Parathyroid cysts are rare but clinically significant lesions. They can be functional, mistaken for a thyroid cyst, and/or managed nonoperatively on occasion. METHODS: We identified seven patients (1 male, 6 females) with the diagnosis of parathyroid cyst from 1998 to 2003. RESULTS: Altogether, 33% of the patients had functional cysts. Sestamibi scans were performed in three of the seven patients, including two with functional cysts; none showed focal uptake. In toto, six of the seven cysts (86%) were found in an inferior parathyroid gland. All of the cysts had crystal-clear aspirate. C-terminal parathormone (PTH) levels were obtained from the aspirate from five of the seven (71%) patients. The mean level was 269,736 pg/ml (1970-1,268,074 pg/ml). Surgery was performed in three of the seven (43%) patients. All patients who underwent surgery improved postoperatively based on symptoms and serum levels of calcium and PTH. The four patients (57%) who were treated nonoperatively were subjected to aspiration alone; three (75%) of those patients required multiple aspirations. CONCLUSIONS: Most parathyroid cysts are nonfunctional and are rarely symptomatic. They are usually located in an inferior gland. If aspirated, most of the cysts reaccumulate fluid. Operative management is usually straightforward and alleviates symptoms and any biochemical abnormalities caused by the cyst.

Adult↗
PubMed2006

Cost-effectiveness analysis of parathyroidectomy for asymptomatic primary hyperparathyroidism.

BACKGROUND: Controversy exists concerning the best treatment for asymptomatic primary hyperparathyroidism (PHPT) when the National Institutes of Health consensus conference criteria for parathyroidectomy are not met. We hypothesized that parathyroidectomy would be more cost-effective than observation or pharmacologic therapy for these patients. METHODS: Cost-effectiveness analysis was performed comparing treatment strategies for asymptomatic PHPT. Treatment outcomes, their probabilities, and costs were identified on the basis of literature and cost database review. Outcomes were weighted by using established quality-of-life utility factors. Sensitivity analysis was used to examine the uncertainty of costs and utility estimates in the model. RESULTS: The incremental cost-effectiveness ratio for parathyroidectomy was US dollars 4778 per quality-adjusted life year (QALY) gained. Operation remained cost-effective until the average cost of parathyroidectomy increased from the estimated value of US dollars 4778 to US dollars 14,650. Pharmacologic therapy was not cost-effective unless the annual cost of therapy decreased from an estimated US dollars 7406 (for cinacalcet) to US dollars 221. Parathyroidectomy ceases to be preferred over monitoring if a quality-of-life difference is not demonstrable after curative operation. CONCLUSIONS: Parathyroidectomy is more cost-effective than observation for managing asymptomatic PHPT patients who do not meet National Institutes of Health criteria for parathyroidectomy. Furthermore, pharmacologic therapies with a greater than US dollars 221 annual cost were not cost-effective in this model.

Cinacalcet↗
PubMed2006

Informed consent, capitation, and conflicts of interest in clinical trials: views from the field.

BACKGROUND: The beliefs of research team members about informed consent practices are not well studied, especially in regard to financial aspects of research such as capitation fees. Sponsors of research offer capitation fees for the enrollment of subjects, and although this money is intended to cover the costs of the research it can sometimes be used in other ways. There is no clear consensus about whether this financial aspect of trials should be part of the informed consent process or whether it represents a potential conflict of interest. METHODS: We presented several hypothetical cases to members of the American College of Surgeons Oncology Group (ACOSOG) at a semi-annual meeting. ACOSOG is a federally funded clinical trials group evaluating surgical and adjuvant methods of cancer treatment. The meeting included surgeons, nurses, case managers, and others involved in clinical surgical trials. RESULTS: We found that most respondents believed that it would be a violation of the protocol to enroll a subject who showed lack of recall about the study. Most respondents also favored disclosure of capitation fees, especially if those fees went into discretionary accounts, but there was some disagreement about the benefit of that disclosure to potential participants. CONCLUSIONS: This study shows the need for greater work in ensuring that research team members share common understandings about informed consent. It also shows that most of these research team participants are prepared to make more disclosure about financial aspects of research than current standards in fact require.

Attitude of Health Personnel↗
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↗