Endocrine Abstracts

Introduction: Paragangliomas are rare neuroendocrine tumors, that manifest as painless, slow-growing masses, becoming evident only when symptoms of catecholamine overproduction or mass effects emerge. Paragangliomas exhibit a broad spectrum of characteristics, existing as solitary or multiple entities, and may be sporadic or hereditary. These tumors can be either benign or malignant and have origin in the sympathetic or parasympathetic tissues. Paragangliomas are commonly found in the pre-aortic and paravertebral sympathetic plexus or in the neck and head and they can be associated with hereditary syndromes, often linked to genes encoding different subunits of succinate dehydrogenase (SDHx). Carriers of SDHB gene mutations have the highest morbidity and mortality rates due to their malignant potential.

Case Report: We present the case of a 16-years-old female patient who had undergone neurosurgical intervention at birth due to Chiari malformation type II and myelomeningocele. The patient was referred for short stature and primary amenorrhea. A left wrist radiograph performed 5 months before indicated delayed skeletal maturation. Pituitary function tests were within normal range (FSH 6.4 mIU/ml, LH 7.5 mIU/ml, estradiol 34 pg/ml, TSH 2.1 mIU/l, FT4 11 pg/ml, 17-β-estradiol 67 pg/ml, cortisol 15 µg/dl, ACTH 35 pg/ml), except for reduced prolactin values (2 ng/ml). Surprisingly, a concurrent encephalic Magnetic Resonance Imaging (MRI), performed during the neurological follow-up, revealed a new left median-paramedian intra-suprasellar rounded lesion of 11 mm, hypointense in T1 and iso-hyperintense in T2, with features suggesting an uncertain nature. Based on the suspicion of astrocytoma or craniopharyngioma, a transnasosphenoidal surgery was performed six months later. The post-operative histologic examination was suggestive of paraganglioma, characterized by consistent morphologic and immunophenotypic features (focal CK+, S100+ in sustentacular cells, and diffuse synaptophysin+). Subsequently, the genetic examination revealed a variant in heterozygosity of exon 7 of the SDHB gene (c.688C>G), with a probable pathogenetic significance. The subsequent follow-ups indicated normal hypothalamic-pituitary-adrenal axis and the onset of menarche at 16.6 years. Postoperative pituitary MRIs confirmed no residual or recurrent disease. Further hormonal and radiological follow-ups were negative.

Conclusion: Despite advances, the imaging of paragangliomas remains challenging, with critical implications for the appropriate diagnostic-therapeutic approach and metastasis detection. The coexistence of paragangliomas and Chiari malformations has already been reported in patients with mutation of EPAS1 and neurofibromatosis type 1. This case suggests the need for further investigations into the genetic correlations of these two conditions, and highlights a possible role for SDHB gene mutations.