Results of transsphenoidal surgery for Cushing's disease in patients with no histologically confirmed tumor

OBJECTIVE: Pathological confirmation of surgical resection of an adenoma fo r Gushing's disease is not always achieved. We reviewed our experience to d etermine the prognostic significance of this lack of confirmation regarding outcome, and we evaluate explanations for this situation. METHODS: The records of all patients undergoing transsphenoidal surgery for Gushing's disease from 1992 to 1998 were reviewed, and those with no histo logical confirmation of tumor were identified. Information regarding preope rative and postoperative hormonal levels and clinical symptoms, preoperativ e magnetic resonance imaging data, intraoperative findings, and the number of reoperations were recorded. RESULTS: There were 29 patients with no confirmation of tumor. Nineteen (66 %) of these patients were cured with surgery and only one had a recurrence of disease, with an average follow-up of 38 months. An abnormality thought to represent an adenoma at the time of surgery was removed in 26 patients ( 90%). Preoperative magnetic resonance imaging suggested a discrete lesion i n 21 patients (72%). Neither intraoperative impression nor magnetic resonan ce imaging appearance was correlated with outcome. CONCLUSION: Patients with no histological confirmation of tumor after trans sphenoidal surgery for Gushing's disease are likely to have a good outcome. The results do not differ significantly from reported cure rates in patien ts with confirmed adenomas. Possible explanations for this situation are di scussed.