Faculty Bibliography

Background Parathyromatosis, described as hyperfunctioning, benign parathyroid tissue scattered throughout the soft tissues of the neck, is a rare cause of recurrent hyperparathyroidism. Fewer than 40 cases have been described in the literature. We describe a case of a woman with recurrent hypercalcemia secondary to parathyromatosis; additionally this is the first reported case of a papillary pattern in parathyromatosis. Clinical Case A 45 year old woman with a history of a left parathyroid adenoma, status post focused parathyroidectomy 10 years ago, presented with constipation, polyuria and abdominal pain. Initial examination demonstrated a well healed cervical scar with no palpable neck masses. Admission laboratory findings were significant for a calcium level of 13.6 mg/dL (n 8-10.4 mg/dL) , ionized calcium 7.7 mg/dL (n 4.6-5.2 mg/dL), phosphorus 2.2 mg/dL (n 2.7-4.5 mg/dL), 25 OH-vitamin D 9.6 ng/mL (n 30-100 ng/mL), PTH 395 pg/mL (n 14-72 pg/mL), PTHrP <0.7 pmol/L (n <2.0 pmol/L) and urine calcium 484 mg/24 hr (n 50-250 mg/24hr). No obvious enlarged parathyroid was localized on neck ultrasound or sestamibi scan. Neck CT showed two 6 mm nodular lesions in the upper mediastinum. The patient had refractory hypercalcemia despite maximal medical therapy. She was taken to the operating room for reoperative neck exploration. She was noted to have diffuse exophytic fronds of tissue covering her left thyroid lobe, which prompted removal of the lobe. Intraoperative PTH decreased from 454 pg/mL to 39 pg/mL. Microsopic examination demonstrated multifocal hypercellular parathyroid nodules in skeletal muscle and perithyroid adipose tissue consistent with parathyromatosis. An unusual pathologic finding was its unique papillary configuration, raising consideration for a parathyroid carcinoma on frozen section. Final pathology confirmed parathyromatosis with no features of carcinoma (vascular invasion, fibrosis or high mitotic activity) with diffuse immunohistochemical reactivity for PTH and non-reactivity for Thyroid Transcription Factor-1. The patient's calcium level was normal post operatively (9.2 mg/dL) with resolution of symptoms. Conclusion Parathyromatosis is a rare disease that raises challenges in diagnosis and management. Preoperative localization of parathyromatosis is difficult, leading to a high surgical failure rate. Scarring and fibrosis from previous neck exploration leads to technical difficulty, since the most common cause for parathyromatosis is seeding of hypercellular parathyroid tissue during previous parathyroidectomy. Medical management is essential during the post-operative period to maintain a normocalcemic state. Our case presents with a pathologic finding of papillary pattern in parathyromatosis, which has not been previously described and can pose a diagnostic challenge in separation from papillary carcinoma on frozen section examination

Background: The incidence of well-differentiated thyroid cancer (WDTC) in the United States is increasing rapidly. Much of this increase is due to the detection by imaging of small, nonpalpable tumors. The incidence of advanced WDTC is also increasing, suggesting a true increase in the incidence of WDTC. This study was performed to determine how WDTCs of all sizes and stages are initially detected. Methods: A retrospective chart review of 519 patients who underwent surgery for WDTC from January 1, 2007, through August 31, 2010, was performed. A total of 473 patients suitable for inclusion in this study were divided into three groups based upon the method by which the tumor was initially detected: tumors detected by an imaging study (184 patients-39%), those detected because a mass was felt in the neck (218 patients-46%), and those detected incidentally on pathological study of the surgical specimen (71 patients-15%). Method of detection was correlated with age and sex of the patient, and size, stage, and nodal status of the tumor. Results: Patients in the Palpation group were more likely to be female (79% vs. 67% vs. 74%), younger (46 vs. 51 vs. 52), and to have larger tumors than those in the Imaging or Incidental groups. In the Imaging group, the tumor was detected on thyroid sonogram in 98 (53%), computed tomography in 38 (21%), magnetic resonance imaging in 19 (10%), carotid duplex scan in 14 (8%), and positron-emission tomography or other imaging studies in 15 (8%). Thirty-three percent of tumors <1 cm, 51% 1-2 cm, 29% 2-4 cm, and 38% >4 cm were first detected on an imaging study. Forty-seven percent of Stage III and IV cancers in patients aged >/=45 years and 39% of patients with positive central nodes were in the Imaging group. Conclusion: This study demonstrates that while most tumors discovered by imaging were small and early stage, almost half of advanced (Stage III and IV) WDTCs were initially discovered by imaging studies. These findings are consistent with the hypothesis that the frequent use of imaging studies may explain not only the increasing incidence of early WDTC, but more advanced thyroid cancers as well.

BACKGROUND: The aim of this study was to compare the performance of students completing an 8-week versus a 6-week surgery clerkship on an objective structured clinical examination (OSCE) and the National Board of Medical Examiners (NBME) clinical science surgery examination. METHODS: One hundred fifteen students from the 8-week clerkship and 99 from the 6-week clerkship were included. Performance on a summative OSCE was assessed using behaviorally anchored checklists. NBME exams were graded using the NBME's standard scaled scores. Results were compared using 2-tailed, independent-samples, unequal-variance t tests. RESULTS: Mean OSCE scores for the 8-week and 6-week curricula were not statistically different. Mean NBME scores also did not statistically differ. Six-week students performed significantly better in the specific OSCE subdomains of blood pressure, orthostatic blood pressure, rectal exam, and fecal occult blood test. CONCLUSIONS: Overall OSCE and NBME exam performance did not differ between 8-week and 6-week surgery clerkship students.

BACKGROUND: The BRAF V600E (BRAF+) mutation activates the mitogen-activated protein kinase (MAPK/ERK) pathway and may confer an aggressive phenotype in papillary thyroid cancer (PTC). Clinically, the behavior of BRAF+ PTC, however, varies from an indolent to an aggressive course. SPRY2 is a negative feedback regulator of the MAPK/ERK pathway. We hypothesize that the level of SPRY2 expression contributes to MAPK/ERK pathway output and accounts for BRAF+ and clinical heterogeneity. METHODS: A tissue microarray with BRAF-positive PTCs (BRAF+ PTCs) was constructed and analyzed for SPRY2 expression and MAPK/ERK output. Data were studied in the context of clinicopathologic factors to develop a risk stratification system predictive of tumor biology. SPRY2 function was studied by silencing SPRY2 in BRAF+ PTC cells. These cells were treated with MAPK/ERK pathway inhibitors and assessed for growth effects. RESULTS: BRAF+ PTCs with an intact MAPK/ERK feedback pathway do not exhibit lymph node metastases. BRAF+ PTCs with dysregulated feedback pathways have nodal metastasis. When SPRY2 is silenced, the BRAF+ PTC cells are significantly more sensitive to MAPK/ERK inhibition. CONCLUSION: PTC behavior likely is dependent on both the driver of the MAPK/ERK pathway and its regulatory feedback. When the feedback pathway is intact, the tumor phenotype seems to be less aggressive. This observation has direct and important clinical implications and may alter our treatment strategies.

BACKGROUND: BRAF V600E mutation is the most common genetic alteration in papillary thyroid cancer (PTC). We used a mutation-specific antibody for immunohistochemical (IHC) detection of the BRAF V600E mutation and correlated expression with clinicopathologic features. The study was designed to validate the accuracy and determine the clinical importance of IHC detection of the BRAF V600E mutation in PTC. METHODS: Direct sequencing and IHC for BRAF V600E mutation was performed in 37 consecutive patients with PTCs. IHC was scored on an intensity proportion scale. IHC positive tumors were stratified into intensity categories. The categories were assessed for clinicopathologic variables, including age, extrathyroidal extension, lymphovascular invasion, and lymph node metastases. RESULTS: A total of 25 PTCs were BRAF V600E-positive and 12 were BRAF mutation-negative on IHC. The BRAF V600E mutation-specific antibody had a sensitivity of 89% and specificity of 100% for detecting the mutation. Tumors with high-intensity staining were more likely to have extrathyroidal extension. CONCLUSION: IHC is an accurate method for the detection of the BRAF V600E mutation in PTC, and its ability to quantify the mutation expression may serve as a better predictor of tumor behavior than molecular sequencing. It provides a potentially rapid, easily applicable, and economic alternative to current techniques.

Patients in a US public hospital were recently found to present with more advanced differentiated thyroid carcinoma (DTC) than those in an adjacent university hospital. 37% of public hospital patients with DTC were primarily Spanish-speaking. We used focus groups and key informant interviews to examine access to care and knowledge of diagnosis/treatment among Spanish-speaking patients with DTC. All adult patients treated for DTC between 2000-2011 and who indicated Spanish as their preferred language met inclusion criteria. Focus groups and key informant interviews were conducted in Spanish by trained facilitators, utilizing a phenomenology approach. Discussions focused on diagnosis and treatment of DTC. 16/50 eligible patients participated. While all expressed a preference for Spanish when discussing medical care, no patient found language to be a barrier due to ready availability of interpreting services. All reported unimpeded access to primary care, with community networks serving as an important information source of public health services. The majority of patients presented with a selfreported nodule or symptoms associated with hypo/hyperthyroidism, which prompted furtherwork-up. DTCwas discovered incidentally on imaging in a small minority of patients. The majority of patients reported limited to no knowledge of thyroid cancer prior to diagnosis. Although only one patient used alternativemedicine as a treatment for thyroid cancer,many expressed a belief in its value as a complementary modality. Access to care proved unhindered among this patient population, though was contingent on strong community networks and availability of interpreter services. Despite limited patient knowledge, DTC was most commonly diagnosed following presentation with a self-discovered nodule or symptoms of hypo/hyperthyroidism. Beliefs in alternative medicine did not affect timely treatment. These data emphasize the importance of patient education and a culturally sensitive approach to optimize care in this demogr!