Fluid-fluid level in pituitary tumors: analysis of management of 106 cases

The management issues of 106 cases of pituitary tumors with a fluid level within the fluid content of the cystic part of the tumor (a "fluid-fluid" level) were reviewed.

Between 2000 and March 2009, 1660 pituitary tumors were treated neurosurgically at K.E.M. Hospital. Investigations of 106 of these cases revealed a fluid-fluid level within the tumor. All patients underwent surgery via a transsphenoidal route. The mean follow-up duration was 46 months.

The tumors varied in size: 31 were between 1 and 3 cm, and 75 were larger than 3 cm in maximum dimension (mean maximum dimension 3.4 cm). Fifty-two tumors had 1 fluid level, 11 had 2, and 43 had multiple fluid levels (> or = 3). The onset of symptoms was acute in 8 cases and insidious in 98 cases. In 16 cases, there was evidence of acute exacerbation of symptoms during the course of symptom progression. The symptoms were progressive in all cases. Ninety-seven percent of patients had visual deficits at the time of presentation. The solid portion of the tumor was relatively friable and vascular in most cases, and the fluid varied in color and in consistency, from a thin yellow to dark red liquid. Visual outcome was extremely gratifying in the majority of cases; of those presenting with visual dysfunction, 94% reported visual recovery in the immediate postoperative period. During the follow-up period, there was tumor recurrence in 21 cases; in 12 of these cases, the authors documented a fluid-fluid level. The histological features did not indicate malignancy in any case.

A fluid level within a fluid cavity in pituitary tumors is rarely reported but is not uncommon in large/giant tumors. The presence of such a feature suggests that surgery in these cases can be relatively straightforward despite the lesion's large size, and the visual outcome is gratifying. However, recurrence rates are relatively higher in such cases than in other pituitary tumors.