Cystic lesions of the pituitary: Clinicopathological features distinguishing craniopharyngioma, Rathke's cleft cyst, and arachnoid cyst

The distinction among craniopharyngioma (CR), Rathke's cleft cyst (RCC), an d intrasellar arachnoid cyst (AC) remains a difficult preoperative problem. Accurate diagnosis of these rare pituitary lesions is important to determi ne the type of treatment and predict prognostic outcome. The majority of th e literature describes the clinical manifestations and management of only o ne of CR, RCC, or AC, rendering comparisons difficult. We conducted a study to 1) investigate distinguishing preoperative clinical, biochemical, and r adiographic features of patients with CR, RCC, and AC; and 2) identify clin icopathological features that independently predict recurrence in CR and RC C in adults. Fifty-two adult patients included 21 patients with CR (mean ag e at initial surgery, 35 +/- 14 yr), 26 patients with RCC (mean age, 37 +/- 14 yr), and 5 patients with AC (mean age, 53 +/- 12 yr). Mean follow-up du ration was 70 +/- 13 months. Patients with CR presented with hypopituitarism in 95% of cases and hyperpr olactinemia in 38%. These patients also had more preoperative neurological deficits (67%), ophthalmological complaints (67%), and significantly higher psychiatric manifestations (33%; P = 0.003) than those with RCC or AC. Pat ients with AC presented with headaches (60%), visual field deficits (60%), or impotence (50%) in the absence of other specific endocrine dysfunction s ymptoms. Using biochemical criteria, the percentage of patients with two or more pituitary hormonal axes impaired preoperatively was 67% for CR and 62 % for RCC, significantly greater (P = 0.03) than that for the AC patients w ho had pituitary dysfunction of only one axis. The composition of CR lesions was cystic (38%), solid (10%), or mixed solid and cystic (43%). Patients with RCC or AC groups had a significantly great er proportion (P = 0.006) of purely cystic lesions (88% and 100%, respectiv ely). Calcification detectable on computed tomographic scanning was present in 87% of patients with CR, a significantly greater proportion (P < 0.001) compared to those with RCC (13%) or AC (0%). No significant differences we re found between the groups based on computed tomography density, the prese nce of postcontrast enhancement, or magnetic resonance imaging. Recurrence rate was 62% for CR, 19% for RCC, and 20% for AC. Surgical intervention sta tistically improved most neurological, ophthalmological, and psychiatric ma nifestations; in contrast, galactorrhea, menstrual dysfunction, and diabete s insipidus (52% CR; 31% RCC) did not improve or became worse postoperative ly. A significantly higher percentage of patients with CR required postoper ative hormone replacement. Similarly, there was a biochemical trend suggest ing that a smaller proportion of patients with CR improved in at least one pituitary axis after surgery (P = 0.08) compared to those with RCC or AC. T here was a positive correlation between cyst size and recurrence rate (r = 0.689; P < 0.01) and between cyst size and time to recurrence (r = 0.582; P = 0.037) for all three groups. We describe the largest clinical, biochemical, radiographic, and histologic al series of adult patients with cystic disease of the sella turcica. Patie nts with AC tended to be alder at initial diagnosis than CR or RCC patients . Mass effects, such as visual problems and headaches, are common symptoms of all three cystic lesions, but psychiatric deficits favor a diagnosis of CR. Calcification or solid components on neuroimaging characterize CR. Endo crinological deficits, especially diabetes insipidus, had the worst prognos is after surgery. Low recurrence rates can be expected for RCC and AC. Thes e data have direct implications for the management and monitoring of patien ts with cystic lesions of the sella turcica.