Encouraging comprehensive and consistent pharmacist education for provision of contraception.

OBJECTIVES: To initiate a call to action for community pharmacists and key stakeholders to encourage comprehensive and consistent education and certification for contraception services, especially in states where laws have been enacted for pharmacist prescribing of hormonal contraceptives. DATE SOURCES: Websites for several boards of pharmacy that have implemented pharmacist training for contraceptive prescribing. SUMMARY: From the authors' perspective of helping to implement laws that allow pharmacist prescribing of contraception in Oregon and Colorado, lessons learned have shown that it is better to have 1 consistent resource for pharmacist certification for the following reasons: 1) Boards of pharmacy are able to ensure patient safety because all pharmacists are providing the same level of care to every patient; 2) retail chain pharmacies and pharmacy managers are assured that all their pharmacists, regardless of state, are trained in a similar and appropriate manner; and 3) pharmacists can be reimbursed through medical insurance for the patient encounter because payers are able to identify and credential pharmacists who pass an approved and accredited certification program. CONCLUSION: New laws allowing pharmacists to prescribe contraception are expanding to other states, and the implementation of these laws provides an important increase in pharmacists' scope of practice. This exciting new prospect allows the pharmacy community of each state an opportunity to coordinate and learn from each other on best practices for implementation. Having a consistent training program was identified as being one key aspect of successful implementation.

In vivo nitric oxide suppression of lipolysis in subcutaneous abdominal adipose tissue is greater in obese than lean women.

Mounting evidence suggests there is a reduced mobilization of stored fat in obese compared to lean women. It has been suggested that this decreased lipid mobilization may lead to, or perpetuate, the obese state; however, there may be a beneficial effect of reduced lipolysis, either by allowing for a sink of excess fatty acids, or by limiting a potentially harmful rise in interstitial and circulating fatty acid concentration. Nitric oxide (NO) may be responsible for a portion of the reduced in vivo rates of lipolysis in obese women because NO reduces adipose tissue lipolysis and adipose tissue nitric oxide synthase (NOS) mRNA is higher in obese than lean individuals. The purpose of this study was to determine if the inhibition of NOS by L-N(g)-monomethyl-L-arginine (L-NMMA) in the absence and presence of lipolytic stimulation would result in a larger increase in lipolytic rate in obese (OB) than lean (LN) women. Microdialysis probes were inserted into the subcutaneous abdominal adipose tissue of seven obese and six lean women to monitor lipolysis. Dialysate glycerol concentration increased in response to L-NMMA in OB (basal 125 ± 26 µmol/l; L-NMMA 225 ± 35 µmol/l) to a greater extent than in LN (basal 70 ± 18 µmol/l; L-NMMA 84 ± 20 µmol/l) women (P < 0.05). Dialysate glycerol increased to a similar extent in OB and LN in response to adrenergic stimulation by isoprenaline or norepinephrine in the presence of L-NMMA. The differential glycerol responses to L-NMMA between obese and lean could not be explained by differential blood flow responses. It can be concluded that NO suppresses basal lipolysis in obese women to a greater extent than in lean women.

Closing the door on pharma? A national survey of family medicine residencies regarding industry interactions.

PURPOSE: To assess the extent and type of interactions U.S. family medicine residencies permit industry to have with medical students and residents. METHOD: In 2008, the authors e-mailed a four-question survey to residency directors or coordinators at all 460 accredited U.S. family medicine residencies concerning the types of industry support and interaction permitted. The authors conducted quantitative and qualitative analyses of survey responses and written comments. Residencies that did not permit any industry food, gifts, samples, or support of residency activities were designated "pharma-free." RESULTS: The survey response rate was 62.2% (286/460). Among responding family medicine residencies, 52.1% refused drug samples, 48.6% disallowed industry gifts or food, 68.5% forbade industry-sponsored residency activities, and 44.1% denied industry access to students and residents at the family medicine center. Seventy-five residencies (26.2%) were designated as "pharma-free." Medical-school-based and medical-school-administered residencies were no more likely than community-based residencies to be pharma-free. Among the 211 programs that permitted interaction, 68.7% allowed gifts or food, 61.1% accepted drug samples, 71.1% allowed industry representatives access to trainees in the family medicine center, and 37.9% allowed industry-sponsored residency activities. Respondents commented on challenges inherent to limiting industry interactions. Many programs noted recent changes in plans or practices. CONCLUSIONS: Most family medicine residencies limit industry interaction with trainees. Because industry interactions can have adverse effects on rational prescribing, residency programs should assess the benefits and harms of these relationships.

Ongoing beta-cell turnover in adult nonhuman primates is not adaptively increased in streptozotocin-induced diabetes.

OBJECTIVE: ß-Cell turnover and its potential to permit ß-cell regeneration in adult primates are unknown. Our aims were 1) to measure ß-cell turnover in adult nonhuman primates; 2) to establish the relative contribution of ß-cell replication and formation of new ß-cells from other precursors (defined thus as ß-cell neogenesis); and 3) to establish whether there is an adaptive increase in ß-cell formation (attempted regeneration) in streptozotocin (STZ)-induced diabetes in adult nonhuman primates. RESEARCH DESIGN AND METHODS: Adult (aged 7 years) vervet monkeys were administered STZ (45-55 mg/kg, n = 7) or saline (n = 9). Pancreas was obtained from each animal twice, first by open surgical biopsy and then by euthanasia. ß-Cell turnover was evaluated by applying a mathematic model to measured replication and apoptosis rates. RESULTS: ß-Cell turnover is present in adult nonhuman primates (3.3 ± 0.9 mg/month), mostly (~80%) derived from ß-cell neogenesis. ß-Cell formation was minimal in STZ-induced diabetes. Despite marked hyperglycemia, ß-cell apoptosis was not increased in monkeys administered STZ. CONCLUSIONS: There is ongoing ß-cell turnover in adult nonhuman primates that cannot be accounted for by ß-cell replication. There is no evidence of ß-cell regeneration in monkeys administered STZ. Hyperglycemia does not induce ß-cell apoptosis in nonhuman primates in vivo.

Outcomes of patients with esophageal cancer staged with [¹8F]fluorodeoxyglucose positron emission tomography (FDG-PET): can postchemoradiotherapy FDG-PET predict the utility of resection?

PURPOSE: To determine whether [(18)F]fluorodeoxyglucose positron emission tomography (FDG-PET) can delineate patients with esophageal cancer who may not benefit from esophagectomy after chemoradiotherapy. PATIENTS AND METHODS: We reviewed records of 163 patients with histologically confirmed stage I to IVA esophageal cancer receiving chemoradiotherapy with or without resection with curative intent. All patients received surgical evaluation. Initial and postchemoradiotherapy FDG-PET scans and prognostic/treatment variables were analyzed. FDG-PET complete response (PET-CR) after chemoradiotherapy was defined as standardized uptake value ≤ 3. RESULTS: Eighty-eight patients received trimodality therapy and 75 received chemoradiotherapy. Surgery was deferred primarily due to medical inoperability or unresectable/metastatic disease after chemoradiotherapy. A total of 105 patients were evaluable for postchemoradiotherapy FDG-PET response. Thirty-one percent achieved a PET-CR. PET-CR predicted for improved outcomes for chemoradiotherapy (2-year overall survival, 71% v 11%, P < .01; 2-year freedom from local failure [LFF], 75% v 28%, P < .01), but not trimodality therapy. On multivariate analysis of patients treated with chemoradiotherapy, PET-CR is the strongest independent prognostic variable (survival hazard ratio [HR], 9.82, P < .01; LFF HR, 14.13, P < .01). PET-CR predicted for improved outcomes regardless of histology, although patients with adenocarcinoma achieved a PET-CR less often. CONCLUSION: Patients treated with trimodality therapy found no benefit with PET-CR, likely because FDG-PET residual disease was resected. Definitive chemoradiotherapy patients achieving PET-CR had excellent outcomes equivalent to trimodality therapy despite poorer baseline characteristics. Patients who achieve a PET-CR may not benefit from added resection given their excellent outcomes without resection. These results should be validated in a prospective trial of FDG-PET-directed therapy for esophageal cancer.

Dual radiotracer analysis of cholinergic neuronal changes in prediabetic mouse pancreas.

BACKGROUND: Pancreatic neuronal changes associated with beta cell loss in type 1 diabetes mellitus are complex, involving, in part, parasympathetic mechanisms to compensate for preclinical hyperglycemia. The parasympathetic neurotransmitter acetylcholine (ACh) mediates insulin release via M3 muscarinic receptors on islet beta cells. The vesicular ACh transporter (VAChT) receptor has been shown to be a useful marker of cholinergic activity in vivo. The positron emission tomography (PET) radiotracer (+)-4-[(18)F]fluorobenzyltrozamicol ([(18)F]FBT) binds to the VAChT receptor on presynaptic cholinergic neurons and can be quantified by PET. The compound 4-diphenylacetoxy-N-methylpiperidine (4-DAMP), available in a tritiated form, binds to M3 muscarinic receptors on beta cells and is a potential target for assessing pancreatic beta cell mass. In this study, we investigate the feasibility of dual radiotracer analysis in identifying neurofunctional changes that may signify type 1 diabetes mellitus in its early preclinical state. METHODS: Ex vivo determinations of pancreatic uptake were performed in prediabetic nonobese diabetic mice and controls after intravenous injection of [(18)F]FBT or 4-[(3)H]DAMP. Beta cell loss in prediabetic mice was confirmed using immunohistochemical methods. RESULTS: [(18)F]FBT uptake was significantly higher in prediabetic pancreata than controls: 3.22 +/- 0.81 and 2.51 +/- 1.04, respectively (P < 0.03). 4-[(3)H]DAMP uptake was significantly lower in prediabetic pancreata than controls: 0.612 +/- 0.161 and 0.968 +/- 0.364, respectively (P = 0.01). CONCLUSIONS: These data suggest that a combination of radiotracer imaging agents that bind to neuronal elements intimately involved in insulin production may be an effective method of evaluating changes associated with early beta cell loss using PET.

Enhanced cholinergic response in pancreata of nonhuman primates with impaired glucose tolerance shown on [18F]fluorobenzyltrozamicol positron emission tomography.

BACKGROUND: Islet cell adaptation to insulin resistance in type 2 diabetes mellitus may be due in part to increased stimulation of beta cells by the autonomic nervous system. The parasympathetic neurotransmitter acetylcholine (ACh) mediates insulin release via M3 muscarinic receptors on islet beta cells. The vesicular ACh transporter (VAChT) receptor correlates with cholinergic activity in vivo. The positron emission tomography (PET) radiotracer (+)-4-[18F]fluorobenzyltrozamicol ([18F]FBT) binds to the VAChT receptor on presynaptic cholinergic neurons and can be quantified by PET. In this study, we utilize [18F]FBT PET to demonstrate pancreatic cholinergic activity before and after dextrose infusion in nonhuman primates with normal (NGT) and impaired (IGT) glucose tolerance. METHODS: Seven adult female vervet (Chlorocebus aethiops) monkeys were maintained on an atherogenic Western diet. They were divided into two groups: four with NGT and three with IGT. Each subject underwent [18F]FBT PET twice: first, a baseline PET under fasting conditions; and second, PET under fasting conditions but after intravenous infusion of dextrose solution. Quantitative analysis of pancreatic uptake at 60 min post-injection was performed. RESULTS: There was no difference in pancreatic uptake of [18F]FBT on baseline scans between the two groups. Pancreatic uptake of [18F]FBT increased in every subject after dextrose infusion (P = 0.03). On post-dextrose PET scans, pancreatic uptake of [18F]FBT was significantly higher in IGT subjects compared with NGT subjects (P = 0.03). The post-dextrose to pre-dextrose uptake ratios were higher in IGT subjects (P = 0.08). CONCLUSIONS: Acute increases in pancreatic cholinergic activity in vivo were detected in the pancreata of nonhuman primates with NGT and IGT after intravenous dextrose infusion on [18F]FBT PET. In subjects with IGT, this activity was significantly higher, suggesting increased autonomic nervous system stimulation of the pancreatic islets in insulin-resistant subjects.

Left ventricular infarct size assessed with 0.1 mmol/kg of gadobenate dimeglumine correlates with that assessed with 0.2 mmol/kg of gadopentetate dimeglumine.

OBJECTIVE: To determine myocardial infarct (MI) size during cardiovascular magnetic resonance at 1.5 Tesla using 0.1 mmol/kg body weight of gadobenate dimeglumine (Gd-BOPTA) and 0.2 mmol/kg body weight of gadopentetate dimeglumine (Gd-DTPA). METHODS: Twenty participants (16 men, 4 women), aged 58 +/- 12 years, with a prior chronic MI were imaged in a crossover design. Participants received 0.2 mmol/kg body weight of Gd-DTPA and 0.1 mmol/kg body weight of Gd-BOPTA on 2 occasions separated by 3 to 7 days. RESULTS: The correlations were high between Gd-DTPA and Gd-BOPTA measures of infarct volume (r = 0.93) and the percentage of infarct relative to left ventricular myocardial volume (r = 0.85). The size and location of the infarcts were similar (P = 0.9) for the 2 contrast agents. Interobserver correlation of infarct volume (r = 0.91) was high. CONCLUSIONS: In chronic MI, late gadolinium enhancement identified with a single 0.1 mmol/kg body weight dose of Gd-BOPTA is associated in volume and location to a double (0.2 mmol/kg body weight) dose of Gd-DTPA. Lower doses of higher relaxivity contrast agents should be considered for determining left ventricular myocardial infarct size.

Prediction of cardiac events in patients with reduced left ventricular ejection fraction with dobutamine cardiovascular magnetic resonance assessment of wall motion score index.

OBJECTIVES: The purpose of this study was to assess the utility of dobutamine cardiovascular magnetic resonance (DCMR) results for predicting cardiac events in individuals with reduced left ventricular ejection fraction (LVEF). BACKGROUND: It is unknown whether DCMR results identify a poor cardiac prognosis when the resting LVEF is moderately to severely reduced. METHODS: Two hundred consecutive patients ages 30 to 88 (average 64) years with an LVEF 40%. CONCLUSIONS: In individuals with mild to moderate reductions in LVEF (40% to 55%), dobutamine-induced increases in WMSI forecast MI and cardiac death to a greater extent than an assessment of resting LVEF. In those with an LVEF <40%, a dobutamine-induced increase in WMSI does not predict MI and cardiac death beyond the assessment of resting LVEF.

Brain abnormalities detected on whole-body 18F-FDG PET in cancer patients: spectrum of findings.

OBJECTIVE: The purpose of this article is to discuss and show examples of the PET appearance of common brain abnormalities that radiologists encounter when interpreting whole-body 18F-FDG PET examinations of cancer patients. CONCLUSION: Knowledge of the PET appearance of various brain abnormalities can yield diagnostically relevant information in cancer patients. Detection of brain abnormalities on whole-body PET often requires adjusting window settings to reduce the intensity of normal brain FDG activity. Often, close correlation of PET/CT and MRI with clinical history offers the most complete radiologic diagnosis.

L-citrulline reduces time to exhaustion and insulin response to a graded exercise test.

PURPOSE: Oral L-arginine supplementation has been shown to improve treadmill time to exhaustion and resting insulin sensitivity in individuals with peripheral vascular disease and type 2 diabetes, respectively. Furthermore, L-citrulline supplementation increases plasma L-arginine concentration to a level higher than that achieved by oral L-arginine supplementation. The purpose of this investigation was therefore to determine whether time to exhaustion during a graded treadmill test, as well as plasma insulin and glucose profiles, could be improved with oral L-citrulline supplementation in healthy individuals. METHODS: Seventeen young (18-34 yr), healthy male and female volunteers performed incremental treadmill tests to exhaustion following either placebo or citrulline ingestion (3 g 3 h before test, or 9 g over 24 h prior to testing). RESULTS: Steady-state submaximal respiratory exchange ratio and VO2max were not significantly different between placebo and citrulline trials. Treadmill time to exhaustion was lower following citrulline ingestion than during placebo trials (888.2 +/- 17.7 vs 895.4 +/- 17.9 s; P < 0.05; N = 17), which was accompanied by a higher rating of perceived exertion during exercise in the L-citrulline compared with the placebo condition. There was also an increase in plasma insulin in response to this high-intensity exercise in the placebo, but not in the L-citrulline, condition (P < 0.05). CONCLUSIONS: It can be concluded that, contrary to the hypothesized improvement in treadmill time following L-citrulline ingestion, there is a reduction in treadmill time following L-citrulline ingestion over the 24 h prior to testing. The normal response of increased plasma insulin following high-intensity exercise is also not present in the L-citrulline condition, indicating that L-citrulline ingestion may reduce nitric oxide-mediated pancreatic insulin secretion or increased insulin clearance.

Predictive value of 18-fluoro-deoxy-glucose-positron emission tomography (18F-FDG-PET) in the identification of responders to chemoradiation therapy for the treatment of locally advanced esophageal cancer.

OBJECTIVE: To evaluate the utility of F-FDG-PET in predicting response to concomitant chemoradiation in locally-advanced esophageal cancer. SUMMARY BACKGROUND DATA: Approximately 25% of esophageal cancer patients experience a pathologic complete response (pCR) to preoperative chemoradiation therapy. Computed tomography, endoscopy, and endoscopic ultrasound are unable to identify patients experiencing a pCR. Growing evidence supports the use of F-FDG-PET in the staging of esophageal cancer in its ability to detect occult metastatic and lymph nodal disease. The identification of patients with a pCR to chemoradiation could potentially spare those patients the morbidity associated with a resection. METHODS: Eligibility criteria included T3-T4N0M0 or T1-T4N1M0 esophageal cancer. Patients underwent an initial F-FDG-PET before treatment and then repeated 4 to 6 weeks after chemoradiation, prior to the esophagectomy. Chemoradiation consisted of: cisplatinum, 5-fluorouracil, and radiation to a median dose of 50.4 Gy. Pathologic response was determined from a systematic review of the esophagectomy specimens. RESULTS: Sixty-four patients have completed therapy to date. Response was as follows: pCR 27%, pathologic residual microscopic (pCRmicro) 14.5%, partial response 19%, and stable or progressive disease 39.5%. A pretreatment standardized uptake value (SUVmax1hour) > or = 15 was associated with an observed 77.8% significant response (pCR + pCRmicro) compared with 24.2% for patients with a pretreatment SUVmax1hour < 15 (P = 0.005). Significant response was observed in 71.4% of patients with a decrease in SUVmax1hour > or = 10 compared with 33.3% when the SUVmax1hour decreased <10 (P = 0.004). CONCLUSIONS: Pretreatment and posttreatment F-FDG-PET can be useful for predicting significant response to chemoradiation in esophageal cancer. These data should be considered in evaluation of patients for esophagectomy after chemoradiation.

Reversal of hypermetabolic brown adipose tissue in F-18 FDG PET imaging.

OBJECTIVES: With the increasing application of F-18-fluorodeoxyglucose (FDG) positron emission imaging, there has been an evolving appreciation for the range of normal variants and the realization that false-positives can lead to serious consequences. RESULTS: One of the most common causes of a false-positive study is the uptake of FDG in areas of hypermetabolic brown adipose tissue (HBAT). Areas of involvement are often spatially closely related to important lymph node groups in the neck, axilla, and upper mediastinum, making critical differentiation difficult, even with PET-CT. CONCLUSIONS: FDG uptake in HBAT has been noted to occur more frequently in cold months and benzodiazepines have been proposed for its prevention. The use of these drugs is, in our experience, of limited value and may complicate patient care in both inpatient and outpatient populations. In this report, we describe considerable success by completely reversing HBAT in 9 of 10 sequential patients with simple core warming maneuvers, which obviate the use of benzodiazepines.

Futility of fluorodeoxyglucose F 18 positron emission tomography in initial evaluation of patients with T2 to T4 melanoma.

BACKGROUND: Evaluation of newly diagnosed patients with melanoma for metastasis is requisite to treatment planning. The reported diagnostic yield of whole-body conventional radiological imaging in initial staging of patients with melanoma is low. However, the diagnostic yield of positron emission tomography (PET) for distant metastases is unclear. HYPOTHESIS: There is no utility of PET as part of a routine metastatic survey in patients with T2 to T4 melanoma. DESIGN: Retrospective review of a cohort study between December 1998 and July 2004. SETTING: University hospital tertiary care center. PATIENTS AND METHODS: There were 64 patients with T2 to T4 melanomas who underwent PET for detection of occult metastases at our institution. All patients underwent surgical excision of the primary lesion and sentinel lymph node dissection. Data included were pathologic findings of the primary lesion and sentinel lymph nodes, laboratory data, and radiological reports. None of the patients had clinically suspected regional or distant metastases prior to PET. The diagnostic yield of PET was evaluated through retrospective analysis. Positive scans were then correlated for accuracy with follow-up imaging, biopsy, and clinical information when available. RESULTS: Positron emission tomography did not reveal occult distant metastases in any of the patients. Positron emission tomographic scans showed no abnormalities in 94% of these patients. In 2 patients (3%), false-positive findings were reported on PET (muscular activity and intranodal melanocytic nevocellular inclusion). Further, PET was not useful in predicting regional lymph node metastases. Nineteen of 64 patients had positive sentinel lymph nodes, and only 2 (11%) were identified on PET. Overall, PET did not change clinical management in any of the patients. CONCLUSIONS: This study suggests no utility for PET in the detection of occult metastases in patients at initial diagnosis of melanoma. Omission of PET imaging from preoperative evaluations for patients with melanoma is recommended.

A prospective evaluation of the impact of 18-F-fluoro-deoxy-D-glucose positron emission tomography staging on survival for patients with locally advanced esophageal cancer.

PURPOSE: To determine the impact of 18-F-fluoro-deoxy-D-glucose positron emission tomography (FDG-PET) in the staging and prognosis of patients with locally advanced esophageal cancer (LAEC). METHODS AND MATERIALS: Between January 2000 and October 2004, all patients with LAEC evaluated in the Department of Radiation Oncology were considered for enrollment into a Phase II trial of preoperative chemoradiation. Entry required a staging whole-body FDG-PET scan. RESULTS: One hundred ten consecutive patients were evaluated; 38 were ineligible for reasons including treatment elsewhere, prior malignancy, or refusal of treatment. After conventional staging (clinical examination, endoscopic ultrasound, and chest/abdominal computerized tomography), 33 patients were ineligible because of metastatic disease or poor performance status. Of the remaining 39 patients, 23 were confirmed to have LAEC after FDG-PET staging and were treated in the Phase II trial (Cohort I). Sixteen patients, however, had FDG-PET findings consistent with occult metastatic disease and were deemed ineligible for the trial but were treated with curative intent (Cohort II). The 2-year survival rate for the 23 patients in Cohort I was 64%, compared with 17% (p=0.003) for patients in Cohort II (FDG-PET positive). CONCLUSIONS: More than one-third of patients determined to have LAEC with conventional staging were upstaged with the use of FDG-PET. Despite comparable therapy, upstaging with FDG-PET predicts poor 2-year survival.

Is parathyroid carcinoma indeed a lethal disease?

BACKGROUND: Parathyroid carcinoma is a rare malignancy with a wide range of aggressiveness. There is no current staging system. Our primary aim was to review the presentation, diagnosis, surgical treatment, and outcomes of patients, with the goal of assessing the incidence of death related to parathyroid carcinoma. METHODS: The authors present a retrospective chart review on patients with parathyroid carcinoma from 1975 to 2004, identified by the tumor registry of a single tertiary-care center. Diagnoses were confirmed histologically, clinical and radiographical data were recorded, and statistical analyses were performed. RESULTS: Twenty-three cases were identified. The mean patient age was 54 years. The female:male ratio was 1.5:1. Follow-up ranged from 1 month to 23 years (median, 134 months). Mean preoperative calcium was 12.9 mg/dL. Median parathyroid hormone was 290 pg/mL. Two patients (9%) had an asymptomatic presentation, and five (22%) presented with a palpable neck mass. Only nine (39%) underwent initial comprehensive en-bloc resection. Median survival was 22 years. Five- and 10-year survival was 85.9% and 69.4%, respectively. Five- and 10-year survival with en-bloc resection was 90% and 67.5%, respectively. Local resection resulted in survival rates of 82.5% and 70.7%. Three of ten deaths were attributed to parathyroid carcinoma. In recurrent disease, computed tomography and scintigraphy had localization rates of 53% and 67%, respectively, with a concordance of 22%. CONCLUSIONS: Long-term survival is possible with parathyroid carcinoma. Death associated with parathyroid carcinoma was uncommon. A staging may be warranted despite the rarity of this disease.

The scintigraphic appearance of subcapsular parathyroid adenomas.

PURPOSE: Approximately 5 to 10% of parathyroid adenomas are located within the thin, fibrous capsule of the thyroid gland. These subcapsular adenomas can complicate minimally invasive parathyroidectomy. The small incision used in this procedure limits the view of the surgical bed. Palpation is less sensitive when the adenoma is covered by the thyroid capsule. If a subcapsular parathyroid adenoma can be identified on preoperative parathyroid scintigraphy, nuclear medicine physicians can recommend exploration of the thyroid capsule early, leading to an easier, more efficient operation. The objective of this observational study was to identify the scintigraphic appearance of subcapsular parathyroid adenomas. MATERIALS AND METHODS: A total of 109 patients with primary hyperparathyroidism underwent preoperative dual-phase Tc-99m sestamibi parathyroid scintigraphy at our tertiary care center from October 2002 to March 2004. Tc-99m pertechnetate was used as a supplemental technique when deemed necessary for optimal interpretation. Retrospective chart review identified 16 surgically proved subcapsular parathyroid adenomas. Parathyroid scintigraphy was reviewed. RESULTS: Subcapsular parathyroid adenomas tend to conform to the expected shape of the thyroid gland. In this small series, subcapsular parathyroid adenomas followed 1 of 3 patterns on lateral images: (1) focal convex distortion of the posterior wall of the thyroid, (2) polar lentiform configuration, and (3) compression of the posterior thyroid parenchyma. CONCLUSION: Subcapsular parathyroid adenomas often have a distinct appearance on scintigraphy. Preoperative identification of this type of parathyroid adenoma can direct a subcapsular surgical approach, optimizing the efficiency of the minimally invasive parathyroidectomy.

Providing optimal preoperative localization for recurrent parathyroid carcinoma: a combined parathyroid scintigraphy and computed tomography approach.

PURPOSE: The incidence of parathyroid carcinoma is approximately 0.5% to 5% in patients with primary hyperparathyroidism. Recurrent parathyroid carcinoma is treated with surgical resection of all sites of disease to ameliorate systemic manifestations of hyperparathyroidism, primarily hypercalcemia. This study investigates the role of parathyroid scintigraphy and computed tomography (CT) imaging in recurrent parathyroid carcinoma. MATERIALS AND METHODS: A retrospective chart review was performed on 8 patients diagnosed with recurrent parathyroid carcinoma at our tertiary care institution between 1975 and 2001. Surgical reports, histopathology, parathyroid scintigraphy, and CT findings were recorded. Surgical reports and radiologic studies were compared for concordance of recurrence sites. RESULTS: There were 32 imaging studies before reoperation: 15 parathyroid scintigraphy and 17 CTs. Of 15 sites of recurrence potentially seen on scintigraphy, 10 were true-positive (67%). Of 17 sites of recurrence potentially seen on CT, 9 were true-positive (53%). Of the 8 false-negatives on CT, 7 of these recurrences were in the surgical bed (88%). There were 9 instances in which CT and scintigraphy were performed preoperatively for comparison and correlation. CT and scintigraphic findings were incongruent in 7 of 9 of these cases (78%). CONCLUSION: Successful surgical intervention for recurrent parathyroid carcinoma requires accurate preoperative localization studies and complete excision of metastases. Our data supports combined analysis of parathyroid scintigraphy and CT for patients with recurrent disease before reoperation. Additionally, our review suggests that sensitivity may be optimized with SPECT parathyroid scintigraphy and close correlation with CT.