Jesse D. Pasternak

18F Fluorocholine PET/MR Imaging in Patients with Primary Hyperparathyroidism and Inconclusive Conventional Imaging: A Prospective Pilot Study

Purpose To investigate the performance of flourine 18 (18F) fluorocholine (FCH) positron emission tomography (PET)/magnetic resonance (MR) imaging in patients with hyperparathyroidism and nonlocalized disease who have negative or inconclusive results at ultrasonography (US) and technetium 99m (99mTc) sestamibi scintigraphy. Materials and Methods This study was approved by the institutional review board. Between May and December 2015, 10 patients (mean age, 70.4 years; range, 58-82 years) with biochemical primary hyperparathyroidism and inconclusive results at US and 99mTc sestamibi scintigraphy were prospectively enrolled. All patients gave informed consent. Directly after administration of 3 MBq/kg of FCH, PET imaging was performed, followed by T1- and T2-weighted MR imaging before and after gadolinium enhancement. Intraoperative localization and histologic results were the reference standard for calculating sensitivity and positive predictive value. The Wilcoxon rank test was used to calculate the mean difference in maximum standardized uptake value (SUVmax) between abnormal parathyroid uptake and physiologic thyroid uptake. The Wilcoxon rank-sum test was performed. Results MR imaging alone showed true-positive lesions in five patients and a false-positive lesion in one patient. FCH PET/MR imaging allowed correct localization of nine of 10 adenomas (90% sensitivity), without any false-positive results (100% positive predictive value). One patient had four-gland hyperplasia, of which three hyperplastic glands were not localized. The median SUVmax of the nine preoperatively identified adenomas was 4.9 (interquartile range, 2.45-7.35), which was significantly higher than the SUV, 2.7 (interquartile range, 1.6-3.8), of the thyroid (P = .008). Conclusion FCH PET/MR imaging allowed localization of adenomas with high accuracy when conventional imaging results were inconclusive and provided detailed anatomic information. More patients must be examined to confirm our initial results, and the accuracy of FCH PET/MR imaging for localization of glands in patients with four-gland hyperplasia remains to be investigated.

Diagnostic performance of computed tomography for parathyroid adenoma localization; a systematic review and meta-analysis

PURPOSE To perform a systematic review and meta-analysis of the sensitivity and positive predictive value (PPV) of CT for preoperative parathyroid localization in patients with primary hyperparathyroidism (pHPT), and subsequently compare the different protocols and their performance in different patient groups. MATERIALS AND METHODS We performed a search of the Embase, Pubmed and Cochrane Library databases to identify studies published between January 1, 2000 and March 31, 2016 investigating the diagnostic value of CT for parathyroid localization in patients with biochemical diagnosis of pHPT. Performance of CT was expressed in sensitivity and PPV with pooled proportion using a random-effects model. Factors that could have affected the diagnostic performance were investigated by subgroup analysis. RESULTS Thirty-four studies evaluating a total of 2563 patients with non-familial pHPT who underwent CT localization and surgical resection were included. Overall pooled sensitivity of CT for localization of the pathological parathyroid(s) to the correct quadrant was 73% (95% CI: 69-78%), which increased to 81% (95% CI: 75-87%) for lateralization to the correct side. Subgroup analysis based on the number of contrast phases showed that adding a second contrast phase raises sensitivity from 71% (95% CI: 61-80%) to 76% (95% CI: 71-87%), and that adding a third phase resulted in a more modest additional increase in performance with a sensitivity of 80% (95% CI: 74-86%). CONCLUSION CT performs well in localizing pathological glands in patients with pHPT. A protocol with two contrast phases seems to offer a good balance of acceptable performance with limitation of radiation exposure.

Application of the new American Thyroid Association guidelines leads to a substantial rate of completion total thyroidectomy to enable adjuvant radioactive iodine

Background. The recently published 2015 American Thyroid Association guidelines recognize lobectomy as a viable alternative for low‐risk cancers and advise more conservative use of radioactive iodine. Some factors indicating adjuvant treatment with radioactive iodine (and therefore completion total thyroidectomy), however, only can be found upon pathologic investigation. Methods. We performed a retrospective analysis including patients with American Thyroid Association low‐ and low‐to‐intermediate risk well‐differentiated thyroid cancer 1–4 cm. We evaluated how often radioactive iodine would be indicated and compared this with our historic rate. A subanalysis was performed to determine the rate of completion total thyroidectomy necessary, based on the indications for adjuvant radioactive iodine therapy. Results. A total of 394/1,000 (39.4%) patients were included for final analysis. Adjuvant radioactive iodine would have been favored in 101/394 (25.6%) of patients, which is 2.5 times less than was given in our historic cohort. Completion total thyroidectomy to enable adjuvant radioactive iodine would have been recommended in 29/149 (19.5%) patients preoperatively eligible for lobectomy. Conclusion. Despite the tightened regulations for radioactive iodine, about 20% of patients with apparently “low‐risk” well‐differentiated thyroid cancer who are eligible for lobectomy may need completion total thyroidectomy because of pathologic findings for which radioactive iodine use is listed as considered or favored by the current guidelines.

Differences Between Bilateral Adrenal Incidentalomas and Unilateral Lesions

IMPORTANCE Adrenal incidentalomas are found in 1% to 5% of abdominal cross-sectional imaging studies. Although the workup and management of unilateral lesions are well established, limited information exists for bilateral incidentalomas. OBJECTIVE To compare the natural history of patients having bilateral incidentalomas with those having unilateral incidentalomas. DESIGN, SETTING, AND PARTICIPANTS Retrospective analysis of a prospective database of consecutive patients referred to an academic multidisciplinary adrenal conference. The setting was a tertiary care university hospital among a cohort of 500 patients with adrenal lesions between July 1, 2009, and July 1, 2014. MAIN OUTCOMES AND MEASURES Prevalence, age, imaging characteristics, biochemical workup, any intervention, and final diagnosis. RESULTS Twenty-three patients with bilateral incidentalomas and 112 patients with unilateral incidentalomas were identified. The mean age at diagnosis of bilateral lesions was 58.7 years. The mean lesion size was 2.4 cm on the right side and 2.8 cm on the left side. Bilateral incidentalomas were associated with a significantly higher prevalence of subclinical Cushing syndrome (21.7% [5 of 23] vs 6.2% [7 of 112]) (P = .009) and a significantly lower prevalence of pheochromocytoma (4.3% [1 of 23] vs 19.6% [22 of 112]) (P = .003) compared with unilateral lesions, while rates of hyperaldosteronism were similar in both groups (4.3% [1 of 23] vs 5.4% [6 of 112]) (P > .99). Only one patient with bilateral incidentalomas underwent unilateral resection. The mean follow-up was 4 years (range, 1.2-13.0 years). There were no occult adrenocortical carcinomas. CONCLUSIONS AND RELEVANCE Bilateral incidentalomas are more likely to be associated with subclinical Cushing syndrome and less likely to be pheochromocytomas. Although patients with bilateral incidentalomas undergo a workup similar to that in patients with unilateral lesions, differences in their natural history warrant a greater index of suspicion for subclinical Cushing syndrome.

Incidental positive lymph nodes in patients with papillary thyroid cancer is independently associated with recurrent disease

Pathological examination occasionally reveals incidental central lymph nodes metastasis (iLNM) after thyroidectomy for patients with papillary thyroid cancer (PTC) who did not undergo compartment‐orientated lymphadenectomy. We aimed to investigate the risk of recurrence for patients with iLNM.

Is it time to reconsider lobectomy in low-risk paediatric thyroid cancer?

Current guidelines recommend total thyroidectomy for nearly all children with well‐differentiated thyroid cancer (WDTC). These guidelines, however, derive from older data accrued prior to current high‐resolution imaging. We speculate that there is a subpopulation of children who may be adequately treated with lobectomy.

De Novo Thyroid Cancer Following Solid Organ Transplantation-A 25-Year Experience at a High-Volume Institution With a Review of the Literature

We investigated the rate, stage, and prognosis of thyroid cancer in patients after solid‐organ transplantations, and compared this to the general population.

PRE-ABLATION THYROGLOBULIN AND THYROGLOBULIN TO THYROID-STIMULATING HORMONE RATIO MAY BE ASSOCIATED WITH PULMONARY METASTASES IN CHILDREN WITH DIFFERENTIATED THYROID CANCER

OBJECTIVE Pediatric differentiated thyroid cancer (DTC) frequently presents with extensive disease. We studied the value of pre-ablation thyroglobulin (Tg) and Tg normalized to thyroid-stimulating hormone (TSH) levels in predicting distant metastases in pediatric patients with DTC. METHODS This is a retrospective cohort study of patients <21 years old who underwent thyroidectomy followed by 131I ablation for DTC at 3 university hospitals over 20 years. Tg levels and the Tg/TSH ratio following surgery but prior to 131I ablation were assessed. The presence of distant metastatic disease was determined from the postablation whole-body scan. RESULTS We studied 44 patients with a mean age of 15.2 years (range 7 to 21 years) and mean tumor size of 2.8 cm. Eight patients had distant metastases and had a higher mean pre-ablation Tg value compared to patients without distant metastases (1,037 μg/L versus 93.5 μg/L, P<.01). The pre-ablation Tg/TSH ratio was also associated with the presence of distant metastases: 12.5 ± 18.8 μg/mU in patients with distant metastases versus 0.7 ± 1.8 μg/mU in patients without (P<.01). A nomogram to predict distant metastases yielded areas under the receiver operating characteristic curve of 0.85 for Tg and 0.83 for Tg/TSH ratio. CONCLUSION After initial thyroidectomy, elevated preablation Tg and Tg/TSH ratio are associated with distant metastatic disease in pediatric DTC. This may inform the decision to ablate with 131I, as well as the dosage. ABBREVIATIONS ATA = American Thyroid Association CI = confidence interval DTC = differentiated thyroid cancer OR = odds ratio ROC = receiver operating characteristic Tg = thyroglobulin.

Noninvasive Follicular Thyroid Neoplasm with Papillary-Like Nuclear Features (NIFTP): Trading Six for a Risky Half Dozen: Reply

Since the term noninvasive follicular neoplasm with papillary-like nuclear features (NIFTP) was introduced, its existence has been controversial. The resultant debate has left clinicians confused as to how to counsel and follow their patients diagnosed with this entity. The authors would like to thank Dr. Rosàrio for his support with respect to our recent article on the clinical safety of renaming encapsulated follicular variant of papillary thyroid carcinoma (EFVPTC) [1]. The authors believe that a continued academic discourse as well as further research on the topic is necessary to clarify the ongoing uncertainty. After Nikiforov et al. [2] published their article suggesting that the nomenclature for the low-risk thyroid cancer variant EFVPTC be changed to NIFTP, the authors found that the experience at the University Health Network was significantly different with respect to both incidence and malignant potential [1]. In addition to Parente et al., there have been several studies indicating that EFVPTC has both malignant potential and a low incidence [1, 3, 4]. The authors certainly support the de-escalation of treatment of these low-risk thyroid cancers including the use of thyroid lobectomy and more selective radioactive iodine ablation. However, the avoidance of the term ‘‘cancer’’ for an entity with malignant potential may result in undertreatment or inappropriate lack of surveillance of patients with these tumors. In this regard, change in terminology is not a substitute for meaningful patient education and multidisciplinary discussion to highlight the low-risk nature of these cancers. Until future research can clarify the current controversy in the literature, clinicians should continue to follow and counsel patients about this low-risk malignant entity. Furthermore, ongoing capture of this diagnostic category by Cancer Registries is essential for both quality improvement and investigational study.

Hemodynamic instability during surgery for pheochromocytoma: comparing the transperitoneal and retroperitoneal approach in a multicenter analysis of 341 patients

Background. Intraoperative hemodynamic instability is a major challenge during adrenalectomy for pheochromocytoma. Typically, pheochromocytoma is performed laparoscopically either through the retroperitoneal or transperitoneal approach. We aimed to determine if the operative approach affects intraoperative hemodynamic instability during surgery for pheochromocytoma in a large multicenter multicenter cohort. Methods. Retrospective, multicenter analysis of consecutive patients with pheochromocytoma who underwent total unilateral laparoscopic adrenalectomy without conversion were included. Statistical analysis was performed using established intraoperative criteria for intraoperative hemodynamic instability: 1) systolic blood pressure >160 mm Hg; 2) systolic blood pressure > 200 mm Hg; 3) mean arterial pressure <60 mm Hg; 4) systolic blood pressure >160 mm Hg + mean arterial pressure <60 mm Hg; and 5) systolic blood pressure >200 mm Hg + mean arterial pressure <60 mm Hg; and 6) intravenous vasopressor + vasodilator. Results. In total, 341 patients met the inclusion criteria, 101 (29.6%) underwent retroperitoneal adrenalectomy and 240 (70.4%) transperitoneal adrenalectomy. Multivariate analysis showed that retroperitoneal adrenalectomy carries greater risk for mean arterial pressure <60 mm Hg (odds ratio 6.255, confidence interval 1.134–34.235, P = .035) compared with transperitoneal adrenalectomy. Overall and cardiovascular morbidity rates were comparable between the 2 approaches. The medical center was a significant independent influencing factor for all 6 intraoperative hemodynamic instability definitions. Conclusion. Variability in institutional management of pheochromocytoma intraoperatively has significant impact on all 6 intraoperative hemodynamic instability definitions. Standardization of anesthesia should be considered to reduce this variability.