Thymic Neuroblastoma in Adults:Report of Three Cases With Special Emphasis on Its Association With the Syndrome of Inappropriate Secretion of Antidiuretic Hormone

Primary Sellar Neuroblastoma Presenting with Syndrome of Inappropriate Secretion of Anti-diuretic Hormone

“…The possibility that euvolaemic hyponatraemia was secondary to low ACTH was also excluded by the normal values of pre-operative plasma ACTH and cortisol and because the hyponatraemia persisted even after replacement with hydrocortisone and thyroxine. Interestingly, neuroblastomas in other locations such as olfactory nerves [19,20], thymus [21,22] have on occasion been described to cause SIADH, even as the sole feature at onset [20]. In two of these cases, ectopic production of ADH in tumour cells was demonstrated by immunohistochemistry [19,21].…”

Malignant Thymoma Associated with Myasthenia Gravis, Graves' Disease, and SIADH

“…or thymic neuroblastoma associated with SIADH (6)(7)(8) × 4 1 mm i n s i z e , wi t h a r e g u l a r p e r i p h e r y i n t h e a n t e r i o r med i a s t i n u m a n d s l i g h t l y i n c r e a s e d F DG u p t a k e ( p S UV= 4 . 0 g / ml ) f o c u s i n t h e a n t e r i o r me d i a s t i n u m c o r r e s p o n d i n g t o t h e a n t e r i o r me d i a s t i n a l ma s s o n t h e CT s c a n ; n o e x t r a me d i a s t in a l u p t a k e wa s n o t e d o n t h e P E T s c a n .…”

Thymoma with ganglioneuroblastomatous component: case report

“…It develops in adults and is often accompanied by the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) [2,3]. Argani et al postulated that thymic epithelial cell progenitors have the potential to differentiate along neural lineage based on their analysis of three cases of thymic neuroblastoma [2]. In our patient, plasma hyponatremia and hypoosmolarity suggestive of SIADH were not preoperatively present.…”

“…Most neuroectodermal tumors arise in the posterior mediastinum and rarely develop in the thymus [2,3,12]. We did not regard this tumor as a collision of a thymoma and a ganglioneuroblastoma tumor because the two elements were confined within a single encapsulated mass and intermingled with each other rather than distinctly separated.…”

“…Nevertheless, the thymic neuroblastic tumor might be a unique entity different from the conventional neuroblastic tumor. It develops in adults and is often accompanied by the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) [2,3]. Argani et al postulated that thymic epithelial cell progenitors have the potential to differentiate along neural lineage based on their analysis of three cases of thymic neuroblastoma [2].…”