Endocrine Abstracts

Introduction: Acromegaly is associated with many different types of benign and malign neoplasm, putatively because of the chronic elevation of IGF-1. Colorectal, thyroid and breast neoplasms are well-established associations; there are many other possible ones, such as prostatic and uterine neoplasms, meningioma, leukemia, lymphoma, renal, pulmonary, esophageal and gastric tumors. Also in the context of MEN-1, parathyroid and pancreatic neoplasms are associated with acromegaly. Synovial sarcoma is an infrequent and very aggressive malignant tumor characterized by a specific chromosomal translocation which fuses the SYT gene from chromosome 18 to a homologous gene (SSX1 or SSX2) at Xp11, resulting in the fusion proteins SYT-SSX1 and SYT-SSX2. The presence of IGF-1 receptors in synovial sarcoma is not universal, but has been associated with higher malignancy. Pazopanib, a tyrosine-kinase inhibitor, has been approved for use in synovial sarcoma; the use of IGF-1 receptor inhibitors is undergoing clinical trials. The association of acromegaly and synovial sarcoma has not been reported so far but is plausible from an etiopathogenetic point of view. We hereby report the case of a patient presenting with a synovial sarcoma after long-standing acromegaly.

Methods: Review of the patient’s records and of the relevant literature

Results (clinical case): A 50-year-old patient complained of a painful nodule of about 3 cm in the medial epicondyle of her right elbow. After surgery the pathology diagnosis was synovial sarcoma, and the postsurgical workup only found two apparently unrelated nodules of 3 and 5 mm diameter in her right lung (CT scan). Due to the appearance of her hands, feet and nose, she was referred to our Endocrinology Clinic with the suspicion of acromegaly. The patient did not complain of any symptoms and her appearance had not substantially changed in the last ten years. Acromegaly was confirmed by high IGF-1 and lack of suppression of GH in OGTT. MEN-1 was excluded. An MR scan showed a 17 mm pituitary adenoma with minor stem displacement, not compromising the cavernous or the optic chiasm. Transsphenoidal surgery was performed, with near-normalization of plasma IGF-1, preservation of the pituitary function and no ionic disturbances; the postsurgical workup including digestive endoscopy, mammography and cardiac ultrasonography is forthcoming.

Conclusions: Both acromegaly and synovial sarcoma are infrequent, and their coincidental association is unlikely. On the other hand, acromegaly is associated with many neoplasms via IGF-1 receptor hyperactivation. Synovial sarcoma should be added to the gamut of suspected acromegalia-associated neoplasms.