Endocrine Abstracts

Epithelioid hemangioendotheliomas (EHE) are rare vascular tumors that are typically low to intermediate grade, but they can also have an aggressive behaviour. Mortality rate is dependent on the tumor location. It is frequently a solitary lesion located in the superficial or deep soft tissues, but they can be found in liver, lungs (normally multifocal), pleura, bones, lymph nodes and rarely in the thyroid gland. We describe a case of metastatic EHE with involvement of the thyroid gland, liver and lungs (probably primary tumor) and aggressive behaviour. A 73-year-old woman was admitted to our hospital due to progressive tiredness, pleuritic pain and episodic cough. Thorax CT scan showed diffuse lung nodularity and micronodularity suggestive of metastatic disease. SARS COV2 infection was excluded. An abdominopelvic CT showed multiple hepatic lesions suggestive of metastases. She underwent lung and liver biopsy both suggestive of EHE (cells with little atypia, round nucleus and rare mitosis, vascular lumens with hemosiderin pigment, CD34+, CD31+). She was also submitted to ultrasound-guided thyroid fine needle aspiration cytology due to a hypoecogenic macronodule, detected on thorax CT, located on the right lobe and isthmus of the thyroid gland, that exceeded the limits of the ultrasonographic image. Thyroid cytology showed moderate cell atypia, CD34+, with features similar to the other biopsy results. She was discharged and referred to Portuguese Oncology Institute. Few days after discharge, she presented at the ER with liquid and solid dysphagia and dyspnea. Neck CT showed a substernal goiter with the right lobe measuring 50 × 65 × 95 mm and mass effect on the larynx, trachea and esophagus, causing an important reduction of laryngeal air column. After a multidisciplinary approach it was decided to perform surgical tracheostomy. During this procedure a biopsy of the cervical mass was performed and showed a malignant epitheliod neoplasm, without vascular differentiation but also areas with features of EHE, co-expression of CK AE1/3 and CD34, expression INI1. Few days later the patient presented with acute respiratory insufficiency and died. Although rare, EHE can have several locations and mimic many other malignant and non-malignant diseases. Involvement of the thyroid gland is very uncommon. Clinicians should be aware of this diagnosis and include it in the differential diagnosis of a cervical mass. Surgery is the usually the treatment of choice in case of primary EHE of the thyroid gland. Our case of metastatic disease had a very bad prognostic and showed an aggressive course.