Impact of subclinical haemorrhage on the pituitary gland in patients with pituitary adenomas

Abstract

Advanced magnetic resonance imaging (MRI) and optical instruments for surgery frequently demonstrate subclinical haemorrhage in pituitary adenomas; however, the effects of subclinical haemorrhage on pituitary glands remain unclear. We sought to clarify the pituitary function in patients with subclinical pituitary adenoma haemorrhage (SPAH). Between January 2006 and December 2012, we retrospectively reviewed 328 consecutive patients who underwent surgery for pituitary adenoma. SPAH was defined as an intratumoral haemorrhage based on both 3 tesla MRI and operative findings, with no clinical symptoms of acute pituitary adenoma apoplexy. The pituitary dysfunction assessed using pre- and postoperative provocative tests was investigated in patients categorized into three groups: nonapoplectic adenoma, adenoma with SPAH and adenoma with clinical apoplexy. The main outcome measure was the incidence of pituitary dysfunction. The overall incidence of nonapoplectic adenomas, adenomas with SPAH and adenomas with clinical apoplexy was 82·3%, 14·3% and 3·4%, respectively. Clinical pituitary apoplexy frequently occurred in male patients with large nonfunctioning adenomas, causing pituitary dysfunction. Contrastingly, the incidence of SPAH was significantly higher in the patients with prolactinoma (P = 0·0260), including those with relatively small adenomas (P = 0·0007). No medications, such as dopamine agonists or somatostatin analogues, were observed to affect the occurrence of SPAH. No deterioration of the pituitary function was observed in the SPAH patients in comparison with the patients with nonapoplectic adenoma, and the size of the haematoma occupying the pituitary adenoma did not exhibit any relationships with the deterioration of the pituitary function. Furthermore, SPAH caused no deterioration of the pituitary function after a surgery based on the postoperative provocation tests. Subclinical pituitary adenoma haemorrhage does not cause any added dysfunction in pituitary glands. Signs of haemorrhage in pituitary adenomas do not necessitate immediate tumour decompression surgery, if there are no symptoms of acute haemorrhage.