Endocrine Abstracts

Paragangliomas (PGLs) and pheochromocytomas (PCCs) are rare tumors that arise from the neuroendocrine tissue along the paravertebral axis with the ability to secrete cathecolamines. Up to 33% of these tumors may be hereditary either alone or as a component of a multiple tumor syndrome. Germline SDHA mutations are relatively frequent (7.6%) in patients with genetically unexplained PGL, even in the absence of familial or clinical indications for inherited PGL. Most of SDHA mutation carriers presented with an apparently sporadic head and neck PGL and extra-adrenal PGL. Lynch Syndrome (LS) is one of the most common cancer susceptibility syndromes. Individuals with Lynch syndrome have a 50%–70% lifetime risk of colorectal cancer, 40%–60% risk of endometrial cancer, and increased risk of several other malignancies. It is caused by germline mutations in the DNA mismatch repair genes MLH1, MSH2, MSH6 or PMS2. We present the case of a woman who underwent surgery in 2008 for retroperitoneal paraganglioma removal. No previous medical history was reported. Ten years later, she presented with mechanical-back pain and headaches. Initial imaging included MRI of the abdomen and lumbar spine and showed bone metastasis in T10-T11-T12. Laboratory investigations included 24-h fractionated urinary catecholamines and metanephrines supporting a functional tumor (plasma normetanephrine 425 mg/24 h and urine normetanephrine 976 mg/24 h). She was treated initially with phenoxibenzamine 20 mg daily in 2 doses and stereotactic body radiation therapy (SBRT), completing a course of 57 Gy in 8 fractions. Genetic testing was also performed. It revealed the expression of 2 mutations in heterozygosis, in both genes SDHA (v481fs* R31) and PMS2. The patient had not suffered from any disease associated with Lynch syndrome until now. It is not common to find these 2 mutations in the same person; in fact, there is not any case described before in the literature. This case report enhances the importance of clinical follow-up in pheochromocytomas and paragangliomas and encourages us to perform genetic testing to prevent the development of malignancies in people who carries oncogenic mutations.