Mediastinal ectopic thyroid diagnosed by endobronchial ultrasound-guided transbronchial needle aspiration: Report of three cases

Personalized Management of Malignant and Non-Malignant Ectopic Mediastinal Thyroid: A Proposed 10-Item Algorithm Approach

We aimed to analyze the management of the ectopic mediastinal thyroid (EMT) with respect to EMT-related cancer and non-malignant findings related to the pathological report, clinical presentation, imaging traits, endocrine profile, connective tissue to the cervical (eutopic) thyroid gland, biopsy or fine needle aspiration (FNA) results, surgical techniques and post-operatory outcome. This was a comprehensive review based on revising any type of freely PubMed-accessible English, full-length original papers including the keywords "ectopic thyroid" and "mediastinum" from inception until March 2024. We included 89 original articles that specified EMTs data. We classified them into four main groups: (I) studies/case series (n = 10; N = 36 EMT patients); (II) malignant EMTs (N = 22 subjects; except for one newborn with immature teratoma in the EMT, only adults were reported; mean age of 62.94 years; ranges: 34 to 90 years; female to male ratio of 0.9). Histological analysis in adults showed the following: papillary (N = 11/21); follicular variant of the papillary type (N = 2/21); Hürthle cell thyroid follicular malignancy (N = 1/21); poorly differentiated (N = 1/21); anaplastic (N = 2/21); medullary (N = 1/21); lymphoma (N = 2/21); and MALT (mucosa-associated lymphoid tissue) (N = 1/21); (III) benign EMTs with no thyroid anomalies (N = 37 subjects; mean age of 56.32 years; ranges: 30 to 80 years; female to male ratio of 1.8); (IV) benign EMTs with thyroid anomalies (N = 23; female to male ratio of 5.6; average age of 52.1 years). This panel involved clinical/subclinical hypothyroidism (iatrogenic, congenital, thyroiditis-induced, and transitory type upon EMT removal); thyrotoxicosis (including autonomous activity in EMTs that suppressed eutopic gland); autoimmune thyroiditis/Graves's disease; nodules/multinodular goiter and cancer in eutopic thyroid or prior thyroidectomy (before EMT detection). We propose a 10-item algorithm that might help navigate through the EMT domain. To conclude, across this focused-sample analysis (to our knowledge, the largest of its kind) of EMTs, the EMT clinical index of suspicion remains low; a higher rate of cancer is reported than prior data (18.8%), incident imagery-based detection was found in 10-14% of the EMTs; surgery offered an overall good outcome. A wide range of imagery, biopsy/FNA and surgical procedures is part of an otherwise complex personalized management.

Ectopic thyroid tissue in the anterior mediastinum along with a normally located gland

Ectopic thyroid tissue is a rare developmental abnormality arising from an aberration in the normal migration of the thyroid gland, from the floor of the primitive foregut to its final position. It is usually asymptomatic, often being diagnosed as an incidental finding. However, it can present with symptoms of compression such as chest pain, cough, stridor, dysphagia, dyspnea and superior vena cava syndrome. Herein, we present the case of a 42-year-old male patient, presenting with dyspnea, chest pain and fatigue. Laboratory tests showed low serum levels of thyroid-stimulating hormone (TSH) and a thoracic computed tomography revealed a heterogeneous mass in the anterior mediastinum. The patient underwent a full surgical resection. The postoperative histopathological examination of the mass demonstrated the presence of benign ectopic thyroid tissue with no evidence of malignancy. This case report emphasizes the importance of taking Ectopic thyroid tissue into account when considering the differential diagnosis of a mediastinal mass, as other common diagnoses including lymphomas, dermoid cysts and thymic tumors, require an entirely distinct treatment approach.

Role of Convex Probe Endobronchial Ultrasound in the Diagnosis and Treatment of Nonmalignant Diseases

Here we present a comprehensive review of the literature concerning the utility of convex probe endobronchial ultrasound (CP-EBUS) in the diagnosis and treatment of nonmalignant conditions and discuss the associated complications. CP-EBUS has been conventionally used for the staging of lung cancer and sampling of mediastinal and hilar nodes. However, its application is not limited to malignant conditions, and it is gaining acceptance as a diagnostic modality of choice for nonmalignant conditions such as tuberculosis, sarcoidosis, pulmonary embolism, thyroid lesions, and cysts. Moreover, its therapeutic value allows for extended applications such as mediastinal and thyroid cyst drainage, fiducial marker placement for radiation therapy, and transbronchial needle injection. The noninvasiveness, low complication rate, high diagnostic yield, and satisfactory sensitivity and specificity values are the main attributes that lend credence to the use of CP-EBUS as a standalone primary diagnostic and therapeutic tool in pulmonary medicine in the foreseeable future.

Diagnosis and management of a mediastinal ectopic thyroid laying on the right bronchus: case report and review of literature

Background

The mediastinal ectopic thyroid is very rare, accounting for less than 1% of all cases of ectopic thyroid tissue. The differential diagnoses with other diseases such as lymphomas, thymic tumors and dermoid cysts is mandatory, in fact each one, needs different management and treatment.

Case presentation

Here, we discuss a rare case of mediastinal ectopic thyroid presenting with a paratracheal mass laying on the right bronchus without symptoms. A 63-year-old male presented with an abnormal well-defined mass along the right paratracheal side, detected by chest x-ray. The CT scan confirmed the presence of a 6 × 8 cm heterogeneously enhanced mass, located behind the superior vena cava and left brachiocephalic artery, reaching azygos vein and right bronchus, without a mass effect. Taking into account the clinical importance of a mediastinal mass, we removed it surgically, through a double surgical approach consisting in a classical transverse cervicotomy for the left thyroid lobe, followed then by a longitudinal sternal splitting to remove the mediastinal mass and complete the thyroidectomy.

Conclusions

In case of mediastinal masses, the surgical excision is recommended, presenting the double advantage to clarify the diagnosis and to treat the pathology. As demonstrated in this case, a mediastinal ectopic thyroid should be taken into account in the differential diagnosis, considering its clinical importance.