LAUSR

Collision tumors represent two morphologically different tumors attached to one another at a single anatomical site. While collision tumors have been reported in various organs, the concomitant presence of a pituitary adenoma with a second sellar lesion is an uncommon occurrence. When this does occur, radiation-induced sarcomas may coexist with a pituitary adenoma as result of previous radiation therapy aimed at treating the pituitary adenoma. Of these, fibrosarcomas are the most common, but rhabdomyosarcomas and chondrosarcomas have also been reported. If patients who have undergone previous radiation therapy are excluded from scrutiny, the presence of these two types of tumor in the same patient becomes even rarer. This report describes the case of a 41-year-old male, without personal or hereditary antecedents of relevance, who was referred to our Neuroendocrinology Unit presenting insidious discomfort and paresthesia in both hands that had developed over the previous 6 months. The patient also reported reduced visual acuity and partial loss of lateral vision over the previous year, accompanied by recurring headaches, which were relieved by analgesic administration. Confrontation visual field tests found bitemporal hemianopsia. Magnetic resonance imaging (MRI) of the sellar region detected a pituitary mass of heterogeneous signal intensity but with well-defined borders, measuring 28 mm × 39 mm × 22 mm, pressing on the optic chiasm. Hormonal study found slight secondary panhypopituitarism due to tumoral compression (FT4: 0.79 ng/dl [0.90--1.70 ng/dl]; TSH: 2.09 IU/ml [0.4--4 IU/ml];