Robotic Resection of Ectopic Thyroid Tissue of the Mediastinum - Case Report and Literature Review.

Introduction: Ectopic thyroid tissue (ETT) is a rare cause of mediastinal masses, representing less than 1% of all mediastinal tumors (1). ETT could be detected anywhere along the path of the first embryonic descent of the thyroid gland from the primordial foregut floor to its usual pre-tracheal position. ETT mediastinal localization accounts for fewer than 1% of all ectopic thyroid cases (2,3). Various surgical methods for approaching mediastinal masses have been documented in the literature, including median sternotomy, posterolateral thoracotomy, and, video-assisted thoracoscopic surgery (VATS) (4). More recently, robotic-assisted thoracoscopic surgery (RATS) has been proposed for these masses. The aim of this article is to present the use of robotic-assisted thoracoscopic surgery (RATS) for a rare case of a mediastinal ETT. Case presentation: We present the case of a 40-year-old male with no significant medical history who discovered a mediastinal mass on a thoracic CT scan following COVID-19 infection. Symptoms were dysphagia and anterior thoracic pain with cervical extension. Scintigraphy confirmed the presence of ectopic thyroid tissue in the mediastinum as well as a normal cervical thyroid gland. ETT was histologically confirmed by endoscopic ultrasound guided biopsy. Robotic assisted surgery was the chosen approach to surgically treat this mass and the technical details are presented. The mass was extracted through the cervical incision. Total surgical time was 230 minutes, and the blood loss was 60 ml. The patient was discharged after 48 hours with follow up showing a full recovery with no residual pain or respiratory symptoms. Conclusion: Ectopic thyroid tissue (ETT) is a rare cause of mediastinal masses, and the diagnosis is always a challenge. Robotic assisted thoracoscopic surgery was proved to be safe and efficient in this rare case of ETT developed in the superior mediastinum.

Long-term outcome of thyroid abnormalities in patients with severe Covid-19.

Objective: We have previously observed thyroid dysfunction, i.e. atypical thyroiditis (painless thyrotoxicosis associated with non-thyroidal illness syndrome), in patients with severe acute respiratory syndrome coronavirus 2 disease (Covid-19). This study aimed to analyse the evolution of thyroid dysfunction over time. Methods: One hundred eighty-three consecutive patients hospitalised for severe Covid-19 without known thyroid history were studied at hospital admission (baseline). Survivors were offered 12-month longitudinal follow-up including assessment of thyroid function, autoantibodies and ultrasound scan (US). Patients showing US focal hypoechoic areas suggestive of thyroiditis (focal hypoechogenicity) also underwent thyroid 99mTc or 123I uptake scan. Results: At baseline, after excluding from TSH analysis, 63 out of 183 (34%) Covid-19 patients commenced on steroids before hospitalisation, and 12 (10%) showed atypical thyroiditis. Follow-up of 75 patients showed normalisation of thyroid function and inflammatory markers and no increased prevalence of detectable thyroid autoantibodies. Baseline US (available in 65 patients) showed focal hypoechogenicity in 28% of patients, of whom 82% had reduced thyroid 99mTc/123I uptake. The presence of focal hypoechogenicity was associated with baseline low TSH (P = 0.034), high free-thyroxine (FT4) (P = 0.018) and high interleukin-6 (IL6) (P = 0.016). Focal hypoechogenicity persisted after 6 and 12 months in 87% and 50% patients, respectively, but reduced in size. After 9 months, thyroid 99mTc/123I uptake partially recovered from baseline (+28%) but was still reduced in 67% patients. Conclusions: Severe Covid-19 induces mild transient thyroid dysfunction correlating with disease severity. Focal hypoechogenicity, associated with baseline high FT4, IL6 and low TSH, does not seem to be related to thyroid autoimmunity and may persist after 1 year although decreasing in size. Long-term consequences seem unlikely.

Thyroid Function, Inflammatory Response, and Glucocorticoids in COVID-19.

The ongoing COVID-19 pandemic calls for extensive research on various medical topics. Since the beginning of the pandemic, multiple studies investigated the impact of SARS CoV-2 on thyroid function. However, crucial data, such as trend progression over time or influence of commonly used drugs, might still be missing. We checked the thyroid function in 174 patients with PCR-confirmed COVID-19. Our research covered three separate time points of hospitalization (days 1, 4, and 10). We did not exclude patients treated with glucocorticoids but, instead, compared them with patients not treated with steroids. We correlated the results of thyroid function tests with markers of systemic inflammation. We checked if abnormal thyroid function can predict unfavorable outcomes defined as combined primary endpoint and/or secondary endpoints; the combined primary endpoint was the occurrence of death, mechanical ventilation, non-invasive ventilation, vasopressor infusion, or prolonged hospital stay, and the secondary endpoint was any of the listed events. In general, 80.46% of evaluated patients displayed abnormalities in thyroid function tests over at least one time point throughout the observation. We noticed a high prevalence of features typical for thyroid dysfunction in non-thyroidal illness (NTI). Free triiodothyronine (fT3) concentration was significantly lower in the group requiring glucocorticoids. Patients displaying abnormal thyroid function were statistically more likely to meet the predefined combined primary endpoint. We found that fT3 measured at admission could be perceived as an independent predictor of endpoint completion for all analyzed groups. Thyroid involvement is common in COVID-19. Our study supports the idea of thyroid function abnormalities being important clinical tools and allowing early recognition of possible detrimental outcomes of the disease.