Thyroglobulin as a Rapid and Cost-Effective Biomarker for Diagnosis of Thyroid Carcinoma Brain Metastasis: A Case Report of a Patient with Metastatic Hurthle Cell Thyroid Carcinoma.

BACKGROUND Brain metastasis of papillary thyroid cancer (PTC) is rare. Treatment of these patients is challenging due to the lack of specific guidelines. Early diagnosis is accompanied by immediate treatment and less morbidity. Total resection of brain lesions may be unattainable when they include infiltration of eloquent areas. This report is of an 81-year-old man who had undergone total thyroidectomy for goiter in the past and presented with metastatic papillary thyroid carcinoma (PTC) to the neck after a gap of 16 years. After two years, the patient developed a solitary cystic brain PTC metastasis associated with raised thyroglobulin (Tg) inside the cystic lesion aspirated during brain surgery. CASE REPORT An 81-year-old male patient was admitted for a space-occupying brain lesion in the right frontal lobe. The patient's history included metastatic disease of PTC to the neck with cervical lymph node metastasis and local recurrence after surgery and radioactive iodine-131 treatment. The patient underwent craniotomy and removal of the lesion. The aspirated fluid was sent for cytological examination and measurement of Tg levels, which were interestingly high. Pathology of the brain lesion revealed infiltration of brain parenchyma from a metastatic lesion characterized by eosinophilic cells with irregular contours forming grooves, resulting in cytoplasmic pseudo-inclusions, an oncotic variant of PTC. CONCLUSIONS This report has shown that residual tissue may be present following total thyroidectomy and may be the origin of PTC with metastasis to the brain. The patient in this study suffered from a brain lesion that could be excised. However, aspiration of cystic compartments could provide a rapid diagnosis in patients with non-removable brain lesions.

High Hereditary Transthyretin-Related Amyloidosis Prevalence in Crete: Genetic Heterogeneity and Distinct Phenotypes.

Background and Objectives: Our goal was to study hereditary transthyretin-related amyloidosis (hATTR) in Crete, Greece. Methods: We aimed at ascertaining all hATTR cases in Crete, an island of 0.62 million people. For this, we evaluated patients with polyneuropathy, autonomic involvement, cardiomyopathy, and/or ophthalmopathy suggestive of hATTR, who presented to the physicians of this study or were referred to them by other physicians. Genetic analyses were performed on all patients suspected of suffering from hATTR. We included in our observational longitudinal cohort study all individuals, residents of Crete, who, during the study period (1993-2019), were found to carry a pathogenic TTR variant. Results: Over the past 27 years, 30 individuals (15 female patients, 15 male patients), from 12 apparently unrelated families, were diagnosed with hATTR, whereas evaluation of their offspring identified 5 asymptomatic TTR pathogenic variant carriers. The most prevalent TTR variant detected was p.Val50Met, affecting 19 patients (11 female patients, 8 male patients) and causing a rather consistent phenotype characterized by predominant polyneuropathy of early adult onset (median age of symptom onset: 30 years; range: 18-37 years). Specifically, patients affected by the p.Val50Met TTR variant experienced progressive sensorimotor disturbances, involving mainly the lower extremities, associated with autonomic and/or gastrointestinal dysfunction. The second most frequent TTR variant was p.Val114Ala, found in 10 patients (4 female patients, 6 male patients) who were affected at an older age (median age of symptom onset: 70 years; range: 54-78 years). This variant caused a predominantly cardiomyopathic phenotype, manifested by congestive heart failure and associated with peripheral neuropathy, carpal tunnel syndrome, and/or autonomic involvement. In these patients, cardiac amyloid deposition was detected on 99m-technetium pyrophosphate scintigraphy and/or heart biopsy. The third TTR variant (p.Arg54Gly) was found in a 50-year-old male patient with ophthalmopathy due to vitreous opacities and positive family history for visual loss. As 22 patients were alive at the end of the study, we calculated the hATTR prevalence in Crete to be 35 cases per 1 million inhabitants. Discussion: Our study revealed that the prevalence of hATTR in Crete is one of the world's highest. Three different pathogenic TTR variants causing distinct clinical phenotypes were identified in this relatively small population pool.