AbstractWe examined the specific cell types in normal human pituitaries that expressed PRL receptor (PRL-R) messenger ribonucleic acid (mRNA) by combined in situ hybridization and immunohistochemistry. The distribution of PRL-R mRNA in 28 pituitary adenomas was examined by in situ hybridization and reverse transcription-PCR in 12 cases of adenomas. In another set of experiments, 34 PRL adenomas from men, women, and bromocriptine-treated patients were analyzed for PRL-R by in situ hybridization.In the normal pituitary, PRL- and LH-producing cells had significantly more mean grain counts per cell and higher percentages of cells positive for PRL-R than GH and TSH cells. PRL-R mRNA was present in all groups of adenomas by in situ hybridization and reverse transcription-PCR. PRL adenomas had a significantly higher density of labeling compared to other adenoma types. Although there was no difference in the levels of PRL-R mRNA in PRL adenomas from men and premenopausal and postmenopausal women, patients treated with bromocriptine before pituitary surgery had significantly lower levels of PRL-R compared to all other groups. These results indicate that in the normal pituitary, PRL and LH cells have the highest level of PRL-R mRNA, whereas PRL adenomas have significantly higher levels of PRL-R mRNA than other types of adenomas, and bromocriptine treatment decreases the levels of PRL-R mRNA in PRL adenomas.
Comparison of Magnetic Resonance Imaging and Computed Tomography in the Preoperative Evaluation of Pituitary Adenomas
Abstract Twenty surgically verified pituitary adenomas were imaged in a systematic comparative fashion with high field strength magnetic resonance imaging (MRI) and computed tomography (CT) before operation. The study group included 11 microadenomas, 4 macroadenomas, 2 recurrent microadenomas, and 3 recurrent macroadenomas. The MRI and CT examinations were evaluated for lesion detection, pituitary stalk displacement, cavernous sinus displacement or invasion, hemorrhage, cystic degeneration within the adenoma, bony erosion, detection of suprasellar extension, and displacement of suprasellar structures. T1 and T2 relaxation characteristics of the adenomas were evaluated on MRI examinations, and contrast enhancement characteristics were evaluated on CT examinations. MRI was superior to CT for detecting the extrasellar extent of tumor. Within the sella turcica, MRI and CT were equivalent with regard to lesion detection, except for 1 patient in whom CT was able to detect a surgically confirmed 3-mm microadenoma that was not visualized on the MRI examination. (Neurosurgery 22:380-385, 1988)
Surgery for Cushing’s Syndrome: An Historical Review and Recent Ten‐year Experience
AbstractBackgroundCushing’s syndrome (CS), due to multiple etiologies, is a disorder associated with the ravages of cortisol excess. The purpose of this review article is to provide a historical synopsis of surgery for CS, review a recent 10‐year period of operative management at a tertiary care facility, and to outline a practical approach to diagnosis and management.Materials and MethodsFrom 1996 to 2005, 298 patients underwent 322 operative procedures for CS at Mayo Clinic, Rochester, Minnesota. A retrospective chart review was carried out. Data was gathered regarding demographics, preoperative assessment, procedures performed, and outcomes. Data are presented as counts and percentages. Five‐year survival rates were calculated where applicable by the Kaplan‐Meier method. Statistical analysis was carried out with SAS, version 9 (SAS Institute, Inc., Cary, NC).ResultsTwo‐hundred thirty‐one patients (78%) had ACTH‐dependent CS and 67 patients (22%) had ACTH‐independent CS. One‐hundred ninety‐six patients (66%) had pituitary‐dependent CS and 35 patients (12%) had ectopic ACTH syndrome. Fifty‐four patients (18%) had cortisol‐secreting adenomas, 10 patients (3%) had cortisol‐producing adrenocortical carcinomas, and 1% had other causes. Cure rates for first time pituitary operations (transsphenoidal, sublabial, and endonasal) were 80% and 55% for reoperations. Most benign adrenal processes could be managed laparoscopically. Five‐year survival rates (all causes) were 90%, 51%, and 23% for adrenocortical adenomas, ectopic ACTH syndrome, and adrenocortical carcinomas, respectively.ConclusionsSurgery for CS is highly successful for pituitary‐dependent CS and most ACTH‐independent adrenal causes. Bilateral total adrenalectomy can also provide effective palliation from the ravages of hypercortisolism in patients with ectopic ACTH syndrome and for those who have failed transsphenoidal surgery. Unfortunately, to date, adrenocortical carcinomas are rarely cured. Future successes with this disease will likely depend on a better understanding of tumor biology, more effective adjuvant therapies and earlier detection. Clearly, IPSS, advances in cross‐sectional imaging, along with developments in transsphenoidal and laparoscopic surgery, have had the greatest impact on today’s management of the complex patient with CS.
The Clinical Conundrum of Corticotropin‐independent Autonomous Cortisol Secretion in Patients with Bilateral Adrenal Masses
Abstract Background Management of patients with bilateral adrenal masses and corticotropin (ACTH)‐independent Cushing syndrome (CS) or subclinical CS is problematic. We report our experience with adrenal venous sampling (AVS) in the evaluation of 10 patients with bilateral masses who had ACTH‐independent CS or subclinical CS. Patients and Methods Ten patients (9 women, 1 man, mean age 56.4 years) with bilateral adrenal masses and ACTH‐independent CS ( n = 3) or subclinical CS ( n = 7) underwent AVS. Autonomous cortisol secretion was documented in all cases with suppressed serum ACTH concentrations and lack of cortisol suppression with dexamethasone administration. Adrenal venous sampling was performed on the second day of dexamethasone administration. Cortisol and epinephrine levels were measured from each adrenal vein (AV) and from a peripheral vein (PV). Results Mean (± SD) maximal diameter of the adrenal masses on computed tomography was 3.3 ± 1.3 cm (range: 1.2–6.0 cm). Successful catheterization was confirmed with AV:PV epinephrine gradients. A cortisol AV:PV gradient >6.5 was consistent with a cortisol‐secreting adenoma in 11 adrenal glands; 5 patients had clinically important bilateral autonomous cortisol hypersecretion, 3 had bilateral cortisol‐secreting adenomas, and 2 had ACTH‐independent macronodular adrenal hyperplasia. Adrenal venous sampling‐guided adrenalectomy was completed in all 10 patients—2 patients had total bilateral adrenalectomy and 2 others had subtotal bilateral adrenalectomy. During a mean follow‐up of 36.1 months (range: 0.7–123 months), CS or clinically important cortisol secretory autonomy did not recur. Conclusions Adrenal venous sampling contributed to the localization of autonomous hypercortisolism in the setting of ACTH‐independent CS or subclinical CS in patients with bilateral adrenal masses.