Metastatic Papillary Thyroid Carcinoma Research Articles

Atypical histiocytoid cells in fine-needle aspiration cytology of metastatic papillary thyroid carcinoma: A potential diagnostic pitfall.

Fine needle aspiration (FNA) cytology of cervical lymph nodes is an effective diagnostic tool to detect metastatic papillary thyroid carcinoma (PTC) when typical cytomorphologic features of PTC are observed. However, the presence of atypical histiocytoid cells (AHCs) due to cystic degeneration sometimes poses a diagnostic challenge. The purpose of this study was to evaluate the presence and cytomorphology of AHCs in metastatic PTC. We analyzed a total of 76 FNA cytological samples of cervical lymph nodes from 66 patients with metastatic PTC diagnosed during approximately 10-year period, from January 2010 to April 2020. Samples were either liquid based preparation (n=53) or conventional smear (n=23). AHCs were present in 38 (50%) of the 76 FNA cases and the remaining 38 cases showed classic PTC features. Among the 38 cases, eight displayed pure AHCs that constituted 10.5% of all the metastatic PTC in the lymph nodes. Pure AHCs were more commonly detected in the liquid based preparation (7/53, 13.2%) than the conventional smear (1/23, 4.3%). The remaining 30 cases had AHCs mixed with the characteristic PTC components. The presence of AHCs was found to be statistically associated with cystic background (p < .002). Metastatic PTC frequently exhibits cystic degeneration and the FNA cytology may not yield classic cytological features of PTC. Pure AHCs composed 10.5% of all cases and might be a potential pitfall for liquid based preparation in diagnosing metastatic PTC. The finding of AHCs within the cystic background should raise the concern of metastatic PTC.

Expression of epithelial membrane protein (EMP) 1, EMP 2, and EMP 3 in thyroid cancer.

Purpose Epithelial membrane protein (EMP) 1, EMP2, and EMP3 are expressed in various types of tumors and have been reported to be involved in carcinogenesis. In this study, we aimed to investigate the expression of these proteins in primary and metastatic thyroid cancer and its clinical implication. Methods EMP1, EMP2, and EMP3 immunohistochemistry was performed using tissue microarrays of 545 primary thyroid carcinomas [338 papillary thyroid carcinoma (PTC), 111 follicular carcinoma (FC), 69 medullary carcinoma (MC), 23 poorly differentiated carcinoma (PDC), and 4 anaplastic carcinoma (AC)] and 59 recurrent or metastatic PTCs. Results EMP1 showed high expression in AC, PTC, FC (P<0.001), and EMP2 was highly expressed in AC (P<0.001). EMP1 and EMP2 were not expressed in stromal cells. Expression of EMP3 in tumor cells [EMP3 (T)] was higher in PDC, PTC, and AC (P<0.001), and expression in stromal cells [EMP3 (S)] was observed only in AC and PTC (P=0.001). The expression of EMP1 (P=0.002) and EMP3 (T) (P<0.001) was higher in conventional PTC than in follicular variant PTC. PTC with BRAF V600E mutation showed higher expression of EMP1 (P<0.001), EMP3 (T) (P<0.001), and EMP3 (S) (P=0.012) than PTC without BRAF V600E mutation. In the PTC without BRAF V600E mutation group, expression of EMP3 (S) was associated with shorter disease free survival (P=0.004). Metastatic PTC showed higher EMP2 (3.4% vs. 0%, P=0.022) and lower EMP3 (T) (44.1% vs. 66%, P=0.001) than primary PTC. Conclusions Expression of EMP1, EMP2, and EMP3 is different according to the subtypes of thyroid cancer. Further studies are needed to determine their role as prognostic markers and treatment target in thyroid cancer.

Hobnail variant of papillary thyroid carcinoma with anaplastic dedifferentiation co-existent with tuberculosis lymphadenitis.

IntroductionThe current study aims to report a rare case of metastatic papillary thyroid carcinoma (PTC) of the cervical lymph nodes with hobnail variant and anaplastic de-differentiation. In addition to the primary disease, there was a second pathology which was caseating granulomatous lymph adenitis suggestive of tuberculosis.Case reportA 91-year-old female presented with a painful right sided neck swelling for two weeks, increased in size suddenly. On clinical examination, there was a well-defined firm painful right sided neck mass. On ultrasound examination, there was multiple well defined solid hypoechoic, hypervascular nodules. These resembled lymph nodes of variable size and shape, mostly in the right side. The patient underwent right lateral cervical lymph node dissection. After the operation, she was sent for radiotherapy.DiscussionThe hobnail variant of PTC is genetically identical to poorly differentiated thyroid carcinoma in that its mutations are in the p53 and TERT promoters are more common in this variant than in conventional PTCs. The proportion of hobnail features have no effect on the outcome. Additionally, 10% of tumor cells with hobnail features were previously linked to a more aggressive clinicopathological aspect.ConclusionAlthough it is rare, metastatic PTC with hobnail variant could undergo anaplastic dedifferentiation.

Abstract 13744: Carotid Sinus Syndrome With Symptomatic Bradycardia Due to Papillary Thyroid Cancer

The patient is a 45-year-old male with no significant past medical history who presents to the hospital for an elective surgical neck mass biopsy. The patient started noticing a slow-growing neck mass six years ago, although he did not seek medical attention. While he was monitored in preoperative room, he developed symptomatic bradycardia. Telemetry showed a complete heart block rhythm. Upon further questioning, he had been having increasing episodes of near syncope for the past two months. Physical examination was significant for bradycardia without an audible murmur. A neck exam revealed a fixed right neck mass palpable across the midline to the left with a prominent thyroid isthmus. Carotid pulses were palpable bilaterally with no bruits. A temporary transvenous pacemaker was placed and the patient was admitted to the hospital for observation. Upon further workups, CT images 1 and 2 in supplemental section. A cervical lymph node biopsy eventually revealed metastatic papillary thyroid carcinoma. The patient was diagnosed with carotid sinus syndrome secondary to papillary thyroid cancer with a vasovagal component. He was discharged with a plan for radiation and close follow-up with an electrophysiologist to evaluate permanent pacemaker eligibility after receiving treatment for thyroid cancer.

ARMC5-associated Bilateral Macronodular Adrenocortical Hyperplasia: A Novel Germline Variant Associated with Concomitant Papillary Thyroid Carcinoma and Meningioma

Abstract Introduction/Objective Germline mutations in the tumor suppressor gene Armadillo-containing repeat protein 5 gene (ARMC5) have been very recently recognized as a cause for a familial form of bilateral macronodular adrenocortical hyperplasia (BMAH), itself a rare cause of Cushing syndrome. In patients with ARMC5 mutations, scattered case reports have also shown an association with meningiomas and cancers of the pancreas, breast, colon, and thyroid. Methods/Case Report We present the case of BMAH, arising in a 61-year-old female with a history of metastatic papillary thyroid carcinoma and meningioma. The patient presented with bilateral but asymmetric adrenal enlargement (right greater than left) and Cushing syndrome. Given history of thyroid cancer and meningioma, genetics referral was ordered. Counseling revealed a pedigree without a strongly evident familial pattern of hereditary endocrine neoplasia characteristic of any of the more common inherited dispositions to endocrine neoplasia. Additionally, a targeted capture-based NGS germline genetic sequencing study for variants in 12 genes associated with associated with hereditary thyroid cancer was performed and negative. However, based on recent scholarship regarding ARMC5, follow-up germline NGS and Sanger sequencing studies encompassing the entire coding sequences of ARMC5 were ordered. These identified a germline, heterozygous, novel (not in ClinVar) but likely pathogenic variant in (c.802C&amp;gt;T, p.Arg268*), providing a likely explanation for the patient’s BMAH. In attempt to control the patient’s Cushing symptoms, right-sided adrenalectomy was performed, revealing a 220g adrenal gland with marked multinodular hyperplasia with solid, nested, and tubular architecture. Results (if a Case Study enter NA) NA Conclusion While case reports exist describing an association between other ARMC5 mutations and BMAH with concomitant meningiomas and/or malignancies, greater study is needed in order to better characterize the phenotypic spectrum of this disease. Our experience with this case not only reports a novel, apparently pathogenic mutation, but it documents its association with BMAH and, additionally, papillary thyroid carcinoma and meningioma.

Risk factors associated with disease-specific mortality in papillary thyroid cancer patients with distant metastases.

Papillary thyroid carcinoma (PTC) is among the most curable cancer types. Even though uncommon, some patients present distant metastatic disease at diagnosis or during the follow-up and most of them have long-term survival. However, there continues to be controversies regarding what clinicopathological features are associated with mortality in these patients. This paper evaluates the factors related to poor disease-specific survival (DSS) in patients with metastatic PTC. A retrospective cohort study included PTC patients with distant metastasis from a tertiary public oncological center. Clinicopathological features, treatment modalities, and outcome were reviewed. Between 1986 and 2014, 108 patients were diagnosed with metastatic PTC. In the multivariate analysis male sex (HR = 2.65; 95%CI: 1.08-6.53; P = 0.033), radioiodine refractory disease (HR = 9.50; 95%CI: 1.23-73.38; P = 0.031) and metastasis at multiple sites (HR = 5.91; 95%CI: 1.80-19.32; P = 0.003) were independent risk factors for death in patients with metastatic PTC. Male patients with metastatic PTC, with radioiodine refractory disease and metastasis at multiple sites have a high risk of death.

Metabolic and functional imaging employment in the differentiation of brown tumors from bone metastases in a case of primary papillary thyroid cancer and parathyroid adenoma: case report

BackgroundBrown tumors are benign osteoclastic bone lesions encountered in patients with hyperparathyroidism. These tumors may demonstrate aggressive, destructive features in the skeleton and imitate metastatic bone lesions, particularly in patients with known primary neoplasm. In this case report of recurrent papillary thyroid cancer and ectopic parathyroid adenoma, we shed light on the importance of combining different nuclear medicine imaging modalities to differentiate brown tumors from metastatic bone lesions.Case presentationWe present a 39-year-old woman with a known history of papillary thyroid carcinoma classic type stage pT1N1b post-total thyroidectomy and radioactive iodine (I-131) therapy (RAI) presented with upper limb weakness and pain. An expansile lytic lesion involving the 6th cervical vertebra was seen in cervical spine MRI, which was suspicious for metastatic deposit. Therapeutic and diagnostic I-131 whole-body scans were negative for any I-13-avid lesions. Laboratory results revealed high calcium, parathyroid hormone, and alkaline phosphatase. A Technetium-99m-sestamibi (Tc-99m MIBI) scan was done with the standard protocol of spot views to the neck and upper chest area to localize any suspicious parathyroid adenoma. The scan demonstrated right supraclavicular and mediastinal Tc-99m MIBI-avid lesions suspicious for being ectopic parathyroid adenomas. Whole-body fluorine-18-2-fluoro-2-deoxy-d-glucose (18F-FDG), positron emission tomography/computed tomography (PET/CT) (18F-FDG PET/CT) was performed for further evaluation. It demonstrated multiple focal lytic skeletal lesions of abnormal increased FDG uptake as well as right supraclavicular FDG-avid lymph nodes. However, the superior mediastinal lesion was non-FDG-avid, suggesting the existence of two different entities: ectopic parathyroid adenoma with multiple brown tumors and metastatic right supraclavicular lymph nodes. The patient underwent right neck dissection and superior mediastinal mass excision. An intra-operative fresh serum parathyroid sample was sent, which dropped down to 100ng/ml from 863.7ng/ml. Later, histopathological results revealed that the right supraclavicular lymph nodes were metastatic papillary thyroid carcinoma. At the same time, the superior mediastinal mass proved to be parathyroid adenoma by histopathology, confirming the 18F-FDG PET/CT findings.ConclusionsIn the case of papillary thyroid carcinoma, metastatic lymph nodes with hyperparathyroidism, and evidence of lytic bone lesions, careful interpretation of the different metabolic and functional imaging modalities are needed to exclude the concurrent parathyroid adenoma and facilitate the differentiation of brown tumors from bone metastases, leading to appropriate surgical and medical treatment plans.

Mixed HPV-related Neuroendocrine Carcinoma and HPV-related Squamous Cell Carcinoma of the Base of Tongue in a Patient With Incidental Identification of Synchronous Metastatic Papillary Thyroid Carcinoma

While it is not uncommon in patients with head and neck cancer to present with multiple metachronous primary neoplasms, rarely do these present as a singular mass composed of intertwined, histologically distinct malignant tumors. Sometimes referred to as collision tumors, these entities are poorly understood and only appear in a handful of case studies in the literature. Here we present a 58-year-old male diagnosed with a human papillomavirus-related collision tumor consisting of oropharyngeal squamous cell carcinoma and small-cell neuroendocrine carcinoma, as well as an incidentally discovered metastatic thyroid papillary carcinoma, despite an unremarkable thyroid gland. The patient underwent transoral robotic base-of-tongue resection and partial pharyngectomy with selective neck dissection followed by chemoradiotherapy. At the 18-month follow-up the patient was doing well. His thyroid was normal and no recurrent or metastatic carcinoma was identified on the computed tomography and positron-emission tomography/computed tomography imaging findings. To the best of our knowledge, this is the first such case in English literature. This case demonstrates the importance of tumor morphology and immunohistochemical testing in HPV-related oropharyngeal carcinomas, despite the overall good prognosis of such tumors, due to the possibility of synchronous or colliding primary neoplasms.

A Pediatric Patient With Papillary Thyroid Carcinoma With Local and Distant Metastases

Introduction: Thyroid cancer is less common among children than adults, but the incidence has been increasing, especially in adolescents. Papillary thyroid carcinoma (PTC) is the most common type of thyroid cancer in pediatric patients representing more than 90% of all cases. Children with PTC are likely to present with regional lymph node metastases, but distant metastases are rare. We present a 12-year-old female patient who presented with a neck mass found to be PTC with neck and pulmonary metastases. Case Presentation: A 12-year-old girl previously healthy presented to her primary doctor with a neck mass for several months. The patient had no other complaints, and the physical exam was notable for a palpable right anterior neck mass measuring 3x4cm. Thyroid studies were remarkable for a thyroid-stimulating hormone (TSH) of 2.13 uIU/mL (0.350-4.94) and negative antithyroid antibodies. Initial neck ultrasound (US) showed a multilobulated right thyroid nodule with macrocalcifications. Fine needle aspiration (FNA) of the nodule revealed PTC. Patient underwent neck and chest computed tomography (CT) preoperatively, notable for cervical lymph nodes involvement and multiple bilateral lung nodes less than 1cm each. She underwent neck exploration and total thyroidectomy and was started on thyroid hormone replacement therapy afterwards. Pathology of the specimen revealed PTC with extension into the perithyroidal soft tissue and two out of five lymph nodes with metastatic PTC. She underwent I-123 whole-body scan (WBS) eight weeks later, followed by I-131 therapy. Interestingly, the pulmonary nodes did not demonstrate any uptake on the WBS before or after receiving I-131 therapy. Patient continues with no pulmonary symptoms and her thyroglobulin (Tg) level continues to be low. She underwent extensive workup that ruled out infections and other malignancy causing the pulmonary nodes. The most recent chest CT, six months after I-131 therapy, showed a slight decrease in the pulmonary nodes. She underwent repeat WBS, 10 months after I-131, notable for minimal uptake in the lungs. The patient is currently euthyroid on thyroid hormone replacement therapy, and she is undergoing surveillance with laboratory studies every three months, neck US and chest CT every six months. Conclusion: In children with PTC, the pulmonary metastases usually demonstrate radioactive iodine uptake, making them responsive to I-131 treatment. Even though the pulmonary nodes were not iodine avid for our patient based on the WBS, it seems like they are responding to the first dose of I-131 as they have decreased in size. Pulmonary metastases in children have different behavior than in adults, and studies have shown that clinical response to I-131 therapy may take several years to show a reduction in the size of nodes. Therefore, careful consideration should be made before giving another dose of I-131 to this group of patients.

Toxic Thyroid Nodule: To FNA or Not?

Background: ATA guidelines recommend evaluation of hyperthyroidism with radioiodine scan and consideration of FNA for non-toxic nodules with suspicious sonographic features. However, there is no standard evidence-based approach to performing ultrasound in patients with toxic nodules. Recent studies have shown increased rates of thyroid cancer in patients with hyperthyroidism and has been shown to demonstrate aggressive histologic features. Clinical Case: A 41-year-old female presented to primary care provider for annual physical exam, found to have intermittent bigeminy and enlarged thyroid on exam. EKG notable for multiple premature ventricular complexes. Evaluation revealed suppressed TSH <0.01 µIU/mL (0.27-4.20), normal free T4 1.27 ng/dL (0.80-1.80), slightly elevated free T3 4.84 pg/mL (2.57-4.43) and elevated TSI 238% (<122). Methimazole was started for treatment of hyperthyroidism. Thyroid sonogram was ordered for abnormal exam, that showed 2.7 cm TIRADS 4 left thyroid nodule with microcalcifications. I-131 uptake values were 20% and 49% at 4-hours and 24-hours, respectively. Technetium-99M scan showed toxic autonomous nodule in the left thyroid lobe corresponding to the one seen on sonogram. The remainder of the thyroid gland showed heterogeneously suppressed uptake. FNA of the thyroid nodule was done due to the presence of microcalcifications and the cytopathology was suspicious for papillary carcinoma. She underwent total thyroidectomy with central neck dissection involving pre-tracheal and paratracheal lymph nodes (level VI). Pathology showed 1.4 cm papillary carcinoma with lymphovascular space invasion and multifocal papillary microcarcinomas in the left thyroid lobe, 0.2 cm papillary microcarcinoma in right thyroid lobe, metastatic papillary carcinoma in 2 out of 5 lymph nodes, largest metastatic deposit 0.1 cm in the largest dimension with no extra nodal extension. There was also follicular hyperplasia noted consistent with Graves’ disease. Post-operatively, she had thyrogen-stimulated adjuvant RAI treatment, dose 107.4 mCi. Post therapy scan did not show evidence of distant metastases. Conclusion: This case demonstrates the identification of a metastatic papillary thyroid carcinoma based on suspicious ultrasound features requiring total thyroidectomy, central neck dissection and adjunct radioactive iodine in a patient with hyperthyroidism from co-existent toxic thyroid nodule and Graves’ disease.

Concurrent Papillary Carcinoma of Thyroglossal Duct Cyst and Thyroid Isthmus, Beyond the Sistrunk Procedure

Introduction/Background: Papillary carcinoma (PC) originating from the thyroglossal cyst is a rare entity. It is even more uncommon to have concurrent thyroglossal duct cyst PC and papillary thyroid carcinomas (PTC). The surgical approach for such patients would involve a combination of a Sistrunk’s procedure and total thyroidectomy. We describe management of a patient found to have multi focal PC originating from a thyroglossal duct cyst and thyroid isthmus with extensive cervical lymph node metastasis. Clinical Case: 30-year-old male presented to PCP with palpable bilateral cervical adenopathy most prominent in the right supraclavicular region. Neck ultrasound confirmed multiple metastatic appearing nodes (largest 4cm) in the central, right and left lateral cervical compartments as well as a hypoechoic, TI-RADS category 5 right thyroid isthmus nodule. FNA of the cervical nodes confirmed metastatic PTC. Neck CT in addition to extensive cervical adenopathy revealed a 2 cm solid mass inferior to the central hyoid bone with infiltrative borders and calcifications suspicious for a primary tumor. Patient underwent total thyroidectomy with central compartment lymph node dissection, excision of thyroglossal cyst and bilateral modified radical neck dissections. Histopathology report revealed a 2.4 cm thyroglossal duct tumor and a 1.1 cm tumor in the thyroid isthmus, confirming two separate tumors both being classical variants of papillary thyroid carcinoma, with no lympho-vascular invasion and 8/53 positive lymph nodes. BRAF V600E mutation was positive. On follow up, the patient is doing well and has deferred adjuvant radioactive iodine treatment for 6 months for personal reasons. Clinical Lesson/ Conclusion: PC of the thyroglossal cyst with synchronous isthmic PTC merits total thyroidectomy and central compartment dissection in addition to the Sistrunk’s procedure, as the likelihood of local metastasis is high. Presence of BRAF V600E mutation has been identified as a predictor of more aggressive behavior in isolated PC of the thyroglossal duct cyst, suggesting a need for more than a Sistrunk’s procedure in such patients. Our patient, who presented with local lymph node metastasis supports this conclusion. Determining BRAF mutation status preoperatively may be a helpful strategy in planning the extent of surgery. Keywords Thyroglossal duct cyst, Papillary thyroid carcinoma, BRAF mutation

Lateral Neck Dissection for Well-Differentiated Thyroid Carcinoma: Is Prophylactic Level V Neck Dissection Necessary? A Retrospective Cohort Study.

The presence of clinically detectable papillary thyroid carcinoma (PTC) metastases in the lateral neck is an indication for neck dissection (ND) and thyroidectomy. Although there is a consensus regarding the importance of therapeutic selective ND of involved levels II to IV in patients with clinically evident locoregional metastatic disease, the prognostic benefit of level V prophylactic ND remains debatable. All patients who underwent thyroidectomy with ND for metastatic PTC between 2006 and 2019 were included in a single-institution retrospective study. Preoperative characteristics at initial presentation, imaging workup, intraoperative findings, and the final histopathological reports were retrieved from the institutional database. A total of 189 patients with locally advanced PTC were identified, of whom 22 (11.6%) patients underwent therapeutic selective ND at levels II to IV together with level V dissection due to clinical involvement. Comparison of the patients who were operated on level V to those who were not revealed no significant difference. The disease recurrence rate was 20.1% throughout an average follow-up of 5.1±3.1 years. No significant differences in recurrence rate were found between patients who underwent and those who did not undergo level V ND (22.7% vs 19.8%, P = .648). No recurrence at resected level V was detected during follow-up, while recurrence at level V was found in 4 (2.1%) patients who did not undergo level V dissection. Evidence of macroscopic and microscopic extrathyroidal extension was significant predictors of disease recurrence risk. There were no significant associations between level V dissection and risk for recurrence. Recurrence at level V was rare (4/189 patients, 2.1%). Our study's findings suggest a low prophylactic benefit of an elective level V ND. Elective level V ND should not be done routinely when lateral ND is indicated but should rather be considered after careful evaluation in high-risk patients.

A Pro-Tumorigenic Effect of Heparanase 2 (Hpa2) in Thyroid Carcinoma Involves Its Localization to the Nuclear Membrane.

Activity of the endo-beta-glucuronidase heparanase, capable of cleaving heparan sulfate (HS), is most often elevated in many types of tumors, associating with increased tumor metastasis and decreased patients’ survival. Heparanase is therefore considered to be a valid drug target, and heparanase inhibitors are being evaluated clinically in cancer patients. Heparanase 2 (Hpa2) is a close homolog of heparanase that gained very little attention, likely because it lacks HS-degrading activity typical of heparanase. The role of Hpa2 in cancer was not examined in detail. In head and neck cancer, high levels of Hpa2 are associated with decreased tumor cell dissemination to regional lymph nodes and prolonged patients’ survival, suggesting that Hpa2 functions to attenuate tumor growth. Here, we examined the role of Hpa2 in normal thyroid tissue and in benign thyroid tumor, non-metastatic, and metastatic papillary thyroid carcinoma (PTC) utilizing immunostaining in correlation with clinicopathological parameters. Interestingly, we found that Hpa2 staining intensity does not significantly change in the transition from normal thyroid gland to benign, non-metastatic, or metastatic thyroid carcinoma. Remarkably, we observed that in some biopsies, Hpa2 is accumulating on the membrane (envelop) of the nucleus and termed this cellular localization NM (nuclear membrane). Notably, NM localization of Hpa2 occurred primarily in metastatic PTC and was associated with an increased number of positive (metastatic) lymph nodes collected at surgery. These results describe for the first time unrecognized localization of Hpa2 to the nuclear membrane, implying that in PTC, Hpa2 functions to promote tumor metastasis.

Misleading 68 GALLIUM-dotatate PET scan in a patient with a history of a phaeochromocytoma: Unsuspected uptake in papillary thyroid carcinoma metastases.

Scanning for somatostatin receptors using 68 Ga-dotatate positron emission tomography with co-registration with computed tomography or magnetic resonance imaging is now in widespread use for the identification of neuroendocrine tumours, phaeochromocytomas, and paragangliomas and their metastases. We present a case where a patient with a phaeochromocytoma showed uptake in her neck considered diagnostic of a head-and-neck paraganglioma, which was subsequently confirmed to be a metastatic papillary thyroid carcinoma. We alert clinicians to such falsely-identified tumours using this extensively used imaging technique.

Pneumatosis intestinalis in a radioactive iodine-refractory metastasic thyroid papillary carcinoma with BRAFV600E mutation treated with dabrafenib\u2013trametinib: a case report

BackgroundPneumatosis intestinalis (PI) is a rare entity which refers to the presence of gas within the wall of the small bowel or colon which is a radiographic sign. The etiology and clinical presentation are variable. Patients with PI may present either with chronic mild non-specific symptoms or with acute abdominal pain with peritonitis. Some cases of intestinal pneumatosis have been reported as adverse events of new oncological treatments such as targeted therapies that are widely used in multiple tumors.Case presentationA 59-year-old caucasian female with radioactive iodine-refractory metastatic thyroid papillary carcinoma with BRAFV600E mutation was treated with dabrafenib and trametinib as a compassionate use. After 4 months treatment, positron emission tomography–computed tomography (PET–CT) showed PI. At the time of diagnosis, the patient was asymptomatic without signs of peritonitis. The initial treatment was conservative and no specific treatment for PI was needed. Unfortunately, after dabrafenib–trametinib withdrawal, the patient developed tumor progression with significant clinical worsening.ConclusionsThis case report is, in our knowledge, the first description of PI in a patient treated with dabrafenib–trametinib. Conservative treatment is feasible if there are no abdominal symptoms.

Low-Grade Nasopharyngeal Papillary Adenocarcinoma: A Review of 28 Patients in a Single Institution.

PurposeLow-grade nasopharyngeal papillary adenocarcinoma (LGNPPA) is a rare nasopharyngeal tumor. This study aimed to analyze the clinical and histopathological features of the disease, and to share our experience of its treatment.Patients and MethodsWe collected demographic data, clinical symptoms, tumor location, pathological features, immunohistochemical results, treatments, and outcomes of 28 patients with pathologically confirmed LGNPPA between 2009 and 2019.ResultsThe median age of the 28 patients was 41.5 years, with a female: male ratio of 1.5:1 (17 females, 11 males). The most common symptom was blood-stained rhinorrhea. The neoplasms were located on the roof of the nasopharynx (RON) in 13 patients, the posterior margin of the nasal septum (PMONP) in 12 patients, the lateral wall of the nasopharynx in one case, and both the RON and PMONP in two patients. Fourteen patients were diagnosed with thyroid-like LGNPPA. Immunohistochemically, the tumors were uniformly positive for cytokeratin 7, cytokeratin 8, vimentin, epithelial membrane antigen, and pan-cytokeratin, and negative for thyroglobulin. Twenty-three patients underwent pure endoscopic surgery, three patients underwent preoperative radiotherapy, and two patients underwent radiotherapy postoperatively. All patients were alive without evidence of lymphatic or distant metastases in the follow-up period (range: 7 to 121 months). Two patients (7%, 2/28) experienced disease recurrence.ConclusionLGNPPA is an indolent tumor with an excellent prognosis. Endonasal endoscopic excision was an effective treatment. It is important to distinguish thyroid-like LGNPPA from metastatic papillary thyroid carcinoma because these diseases have similar microscopic features but different prognoses.

124I-PET/CT-Guided Diagnosis and Personalized Treatment of Metastatic Papillary Thyroid Cancer to the Pancreas.

Metastasis to the pancreas from differentiated thyroid carcinoma is rare. A new pancreatic lesion was identified on surveillance imaging of a man with metastatic papillary thyroid carcinoma 7 years after initial diagnosis. Imaging with 124I-PET/CT was performed to noninvasively confirm metastatic thyroid cancer and provide prospective dosimetry to guide selection of a safe and effective administered activity of 131I. This case demonstrates the emerging role of 124I-PET/CT as a useful diagnostic scan, pretherapy scan, and dosimetric tool to deliver personalized therapy for patients with metastatic thyroid cancer.

Radioactive iodine-125 seed localization as an aid in reoperative neck surgery

BackgroundScarring and disrupted tissue planes add to already-complex neck anatomy and make localization of nonpalpable pathology difficult in cervical endocrine reoperations. We describe the use of radioactive iodine-125 seed localization (RSL) in 6 patients with metastatic papillary thyroid carcinoma (PTC) and 2 with recurrent hyperparathyroidism. MethodsEight patients had 2-D ultrasound-guided RSL of the target lesion, 0–3 days preoperatively. Intraoperative gamma probe (Neoprobe) was used to plan incision placement and localize the implanted seed. Recorded operative variables included: number of lymph nodes (LNs) harvested, estimated blood loss (EBL), operative time, length of stay (LOS) and RSL and operative complications. ResultsAll patients had successful resection of the targeted area and removal of the radioactive seed. There was no seed migration. Two complications occurred in the thyroid group. ConclusionRadioactive iodine 125 seeds facilitate successful localization of endocrine pathology during reoperative cervical procedures.

Non-endodontic periapical lesions clinically diagnosed as endodontic periapical lesions: A retrospective study over 15 years.

BackgroundThis study aimed to provide the frequency and demographic data of non-endodontic periapical lesions clinically misdiagnosed as endodontic periapical lesions from a Southeast Asian population over a 15-year period. Material and MethodsA retrospective study was conducted from departmental archives between 2005 and 2019. Cases clinically diagnosed as endodontic periapical lesions were retrieved. Then, cases with a histopathological diagnosis of non-endodontic periapical lesion were selected. Demographic data of non-endodontic periapical lesions were recorded. Radiographic features of cases with available radiographs were analyzed. ResultsOf 1,566 cases clinically diagnosed as endodontic periapical lesion, 157 cases received a histopathological diagnosis of non-endodontic origin. Eighteen different histopathological diagnoses were identified. The most frequent lesion was dentigerous cyst (n= 51, 32.48%) followed by odontogenic keratocyst (n=31, 19.75%), nasopalatine duct cyst (n=18, 11.46%) and ameloblastoma (n=15, 9.56%). Three cases of malignant tumors, including adenoid cystic carcinoma, mucoepidermoid carcinoma, and metastatic papillary thyroid carcinoma were observed. ConclusionsNon-endodontic periapical lesions constituted 10.03% of cases clinically diagnosed as endodontic periapical lesions. Histopathological examinations of non-endodontic periapical lesions revealed a variety of lesions ranging from foreign body reaction, cysts, fibro-osseous lesions, benign tumors and primary or metastatic malignant tumors. Of clinical significance is that some non-endodontic periapical lesions had different treatment modalities and prognoses compared with endodontic lesions. Therefore, dentists must be aware that periapical radiolucent lesions are not always a consequence of pulpal necrosis. Key words:Ameloblastoma, dentigerous cyst, endodontic periapical lesions, non-endodontic periapical lesions, odontogenic keratocyst.

Complete remission after primary single dose of radioactive iodine in metastatic papillary thyroid carcinoma: a case report

Background: Papillary thyroid cancer (PTC) accounts for 90% of the thyroid malignancies with predominance in females. Distant metastasis is usually seen in lungs and bones. The treatment of metastatic papillary cancer thyroid is total/near total thyroidectomy followed by radioactive iodine (RAI) ablation. Lung metastasis shows good response to RAI therapy. Case Presentation: We describe a case of 22-year-old female, referred to nuclear medicine department after surgery for RAI ablation. Patient was diagnosed case of PTC. First dose of 100 mCi of RAI under steroid cover was given. Post-therapy scan showed bilateral pulmonary metastasis. However, follow up I-131 whole body imaging after 2 years showed no evidence of functioning thyroid tissue/metastasis. Conclusion: PTC with lung metastasis has good prognosis and better survival in young patients treated with RAI. A single dose of RAI (I-131) may cure extensive lung metastasis.