Pituitary incidentaloma diagnosed as acromegaly triggered by trauma: A case report

Pituitary incidentaloma (PI) is a generic term for pituitary tumors that are identified on images acquired for non-malignant conditions. Acromegaly is an extremely rare form of PI. Occasionally, a functional pituitary adenoma (PA) may be misdiagnosed as PI, which may result in a poor clinical outcome. Here we report the first case, to the best of our knowledge, of PI diagnosed as trauma-triggered acromegaly. A 42-year-old man with a chief complaint of head trauma was referred to our hospital after computed tomography (CT) revealed a pituitary tumor. His appearance was suggestive of acromegaly. Mild hypertrophy of the extremities was also observed. Preoperative blood tests, magnetic resonance imaging (MRI), and endocrine tolerance test findings indicated acromegaly. Accordingly, we suspected a growth hormone (GH)-producing PA, and we performed endoscopic transsphenoidal surgery (eTSS). Histopathology showed a densely granulated GH-producing PA, which was also confirmed via immunohistochemistry. Two months after surgery, blood tests showed decreased levels of GH and insulin-like growth factor-1. In addition, a postoperative endocrine tolerance test revealed no abnormalities. There was no recurrence at 24 months after surgery. The findings from this case suggest that PIs can also present as functional adenomas, which can be diagnosed using initial hormone examinations and endocrine tolerance tests. Therefore, thorough endocrine examination is necessary for early diagnosis and treatment and improved patient outcomes.