Jörg Flitsch

Surgical Treatment of Clinically Nonsecreting Pituitary Adenomas in Elderly Patients

OBJECTIVEThe goal of this study was to evaluate the efficacy and safety of transsphenoidal pituitary surgery for elderly patients, using improved techniques of the past decade. METHODSWe retrospectively analyzed 32 surgically treated cases of clinically nonsecreting pituitary adenomas in patients more than 70 years of age (mean, 73.9 ± 3.4 yr). These patients were identified in a review of 982 patients with pituitary adenomas who were treated at University Hospital Eppendorf, Hamburg, between January 1991 and November 1999. RESULTSThe mean preoperative duration of symptoms was 1.9 years (2 wk to 11 yr). The chiasmatic syndrome was present for 27 patients (84.4%). All patients underwent transsphenoidal surgery. Seven patients underwent reoperations. Preoperative assessments of anterior pituitary function revealed growth hormone deficiencies for 21 of 27 patients (77.8%), thyroid insufficiencies for 10 of 30 patients (33.3%), and adrenal insufficiencies for 13 of 29 patients (44.8%). Hypogonadism and hyperprolactinemia were observed for 76.7% and 46.9% of the patients, respectively. All tumors were macroadenomas, ranging from 18 to 50 mm (average, 33.6 mm) in size, including 7 enclosed and 25 invasive adenomas. Complete microscopic tumor resection was achieved in 24 cases, and subtotal removal was performed in 8 cases. There were no severe perioperative complications. In the cases involving hyperprolactinemia, serum prolactin levels were normalized for 8 of 11 patients (72.7%). Normal thyroid function was recovered for 1 of 10 patients (10.0%) with preoperative hypothyroidism. However, growth hormone or adrenal insufficiencies persisted for all patients with preoperative insufficiencies. Visual disturbances were improved for 19 of 23 patients (82.6%). All patients recovered well after surgery, with an average hospital stay of 16.3 days. Histological and immunohistochemical studies demonstrated gonadotroph adenomas in 56.7% of cases, null-cell adenomas in 26.7%, and oncocytomas in 13.3%. CONCLUSIONSurgical treatment of nonsecreting pituitary adenomas causing visual disturbances is standard, even for elderly patients. In this series, transsphenoidal surgery was a safe procedure, with minimal morbidity and excellent tolerance. Age alone is not a contraindication for active treatment, particularly with transsphenoidal surgery.

Genetic variation may influence obesity only under conditions of diet: Analysis of three candidate genes

Under the hypothesis of obesity as a polygenetic disease numerous genes have been associated with an obese phenotype and metabolic co-morbidities. The cannabinoid receptor 1 (CB 1) is part of an underinvestigated system that participates in appetite control. Previous publications suggest that the endocannabinoid systems interact with the better understood leptin-melanocortin axis. Neuropeptide Y (NPY) is a player in the latter. Finally resistin has been shown to influence NPY expression in the brain. In a cohort of 1721 caucasion men and women with a BMI of 25kg/m(2) or more we therefore investigated three candidate polymorphisms at baseline and following 3 months low fat caloric restriction diet by polymerase chain reaction and restriction digestion: the 1359 G/A variant of the cannabinoid receptor 1 (CB1), the L7P variation in neuropeptide Y (NPY) and the -420C>G polymorphism in resistin. Comparing groups according to genotype for each gene separately revealed significant results at baseline only for the CB1 gene. However, upon dieting significant data was found for all 3 genes. Carriers of at least one A allele in CB1 lost more weight and reduced LDL cholesterol more than wildtype patients. LL homocygotes in NPY had a greater reduction in glucose, triglycerides, and LDL cholesterol whereas in resistin carriers of the G allele had a greater reduction in weight and triglycerides. Creating two groups defined by NPY and resistin genotype, respectively, with similar BMI values resulted in significant differences concerning weight loss and metabolic improvement. In conclusion, genetic polymorphisms associated with obesity may become relevant only under the condition of a low calory diet. The presence of a certain genotype may then be beneficial for obesity treatment.

Cushing's disease: a surgical view; This Publication is dedicated to our professor emeritus Dr. med. Rudolf Kautzky

The management of adrenocorticotropic hormone (ACTH)-dependent Cushings disease implies difficulties in the differential diagnosis, in the detection of minute pituitary adenomas, as well as in the radical removal of invasive adenomas. Magnetic resonance imaging (MRI) is unspecific and often negative in minute adenomas of three or less millimeters diameter. The trias of detectable ACTH, suppression of cortisol in the high-dose dexamethasone test, and stimulation in the corticotropin-releasing-hormone (CRH)-test has a high accuracy to prove pituitary dependency. In unclear cases, the use of inferior petrosal sinus sampling (IPSS) or cavernous sinus sampling (CSS) for the exclusion of ectopic ACTH-syndrome is currently advised especially in cases where cranial MRI is negative. The reliability of these methods to localize the mostly lateralized microadenomas is still discussed. Transsphenoidal microsurgical adenomectomy, the accepted primary therapy of Cushings disease, has been published from experienced pituitary centers with remission rates ranging from 70% to 98% in the last decade. False diagnosis (pseudo-Cushing, ectopic ACTH-syndrome), incorrect adenoma localization by IPSS or CSS, and the rate of minute or non-resectable invasive tumors influence the results. The handling of minute specimen implies problems for surgeon and pathologist. Intraoperative tumor localization was improved by ACTH measurement from the cavernous sinus and the adenoma itself, by cytology, and frozen sections. The histology of the anterior lobe (rate of Crookes cells) bears information of clinical relevance. Invasive macroadenomas may deserve repeat microsurgery, medical treatment, and radiosurgery.

Surgical Strategies in Childhood Craniopharyngioma

Craniopharyngiomas are biologically benign lesions (WHO Grade 1) of the sellar and suprasellar region, associated with a serious morbidity. About 50% of these tumors become clinically apparent during childhood. Clinical symptoms include headaches, chiasm syndrome, hydrocephalus, pituitary insufficiencies, and obesity. Growth arrest is a typical symptom in children. The treatment of craniopharyngiomas includes surgery as well as radiotherapy. The goal of surgery varies according to the tumor location and extension and may range from complete resection to biopsy. Surgical complications are well known and cause constant evaluation of surgical strategies. Diencephalic obesity is related to surgical manipulation of hypothalamic tissue. Therefore, a classification system for craniopharyngiomas based on preoperative MRI is suggested by the authors. Recurrences are frequent in craniopharyngiomas, even after complete or gross-total resection. Radiotherapy is therefore recommended to patients with incomplete resections. However, the ideal time for radiotherapy after surgery is under discussion. The treatment of craniopharyngiomas requires an interdisciplinary and multimodal approach. Each patient should receive an individually tailored treatment. Surgically, different approaches as well as different degrees of resection can be considered, depending on tumor location and tumor extension.

BRAF V600E analysis for the differentiation of papillary Craniopharyngiomas and Rathke's Cleft Cysts

The differential diagnosis of cystic epithelial masses of the sellar region, especially the histopathological differentiation of craniopharyngiomas and Rathkes cleft cysts, poses a challenge even to experienced diagnosticians. Recently, BRAF V600E mutations have been described as a genetic hallmark of papillary craniopharyngiomas. We investigated a series of 33 Rathkes cleft cysts to determine the frequency of BRAF V600E mutations and its suitability as an additional diagnostic marker for the differentiation of cystic lesions of the sellar region.

Insights into the Infiltrative Behavior of Adamantinomatous Craniopharyngioma in a New Xenotransplant Mouse Model

Adamantinomatous craniopharyngiomas (adaCP) cause hypothalamic pituitary dysfunction. Elucidation of pathomechanisms underlying tumor progression is essential for the development of targeted chemotherapeutic treatment options. In order to study the mechanisms of tumor outgrowth, we implanted human primary adaCP tissue from three different surgical specimens stereotactically into the brain of immunodeficient mice (n = 20). Three months after tumor inoculation, magnetic resonance imaging and histology confirmed tumor engraftment in all 20 mice (100%) that obtained tissue transplants. The lesions invaded adjoining brain tissue with micro finger‐shaped protrusions. Immunohistochemical comparison of the primary tumor and xenotransplants revealed a similar amount of proliferation (Mib‐1) and cytokeratin expression pattern (KL‐1). Whole tumor reconstruction using serial sections confirmed whirl‐like cell clusters with nuclear β‐catenin accumulations at the tumor brain border. These whirls were surrounded by a belt of Claudin‐1 expressing cells, showed an activated epidermal growth factor receptor (EGFR) and distinct CD133 as well as p21WAF1/Cip1 positivity, indicating a tumor stem cell phenotype. Consistent with our previous in vitro studies, intracranial xenotransplants of adaCP confirmed cells with nuclear β‐catenin and activated EGFR being the driving force of tumor outgrowth. This model provides the possibility to study in vivo tumor cell migration and to test novel treatment regimens targeting this tumor stem cell niche.

Treatment of Primary Hypophysitis in Germany.

CONTEXT The best treatment of primary hypophysitis (PrHy) is a matter of debate. OBJECTIVE Our main objective was to analyze the treatment practice for PrHy in Germany and to compare the outcome of the main treatment options. DESIGN The Pituitary Working Group of the German Society of Endocrinology conducted a nationwide retrospective cross-sectional cohort study. PATIENTS Seventy-six patients with PrHy were eligible for the study. MAIN OUTCOME MEASURES Clinical and endocrinological outcomes, side effects and complications of therapy, initial response, and recurrence rates were assessed. Outcome depending on the treatment modality was evaluated. RESULTS For mere observation, regression of space-occupying lesions was observed in 46%, unchanged size in 27%, and progression reported in 27%. Pituitary function improved in 27% of patients during observation. Deterioration of pituitary function was only found in patients with progressive lesions. The initial response to glucocorticoid pulse therapy was most favorable, with early failure in only 3%. However, the overall failure and recurrence rate was 41%. Recurrence rate was not related to duration of steroid administration. Side effects of steroids occurred in 63%. The surgical approach was transsphenoidal in 94%. The histological subtype was lymphocytic hypophysitis in 70% and granulomatous hypophysitis in 30%. Progression or recurrence was observed in 25% after surgical treatment. CONCLUSION Glucocorticoid pulse therapy is associated with a high recurrence rate. Evidence suggests that surgery is not able to prevent recurrence. Considering the favorable results of observation, conservative management is recommended in PrHy unless symptoms are severe or progressive.

Tight junction protein claudin-1 is differentially expressed in craniopharyngioma subtypes and indicates invasive tumor growth

BACKGROUND Claudins are tight junction proteins expressed in epithelial tissues that play important roles in cell polarity and adhesion. Altered distribution of claudin-1(CLDN1) affects cell mobility and tumor invasiveness. Craniopharyngiomas (CPs) represent epithelial tumors of the sellar region, consisting of adamantinomatous (adaCP) and papillary (papCP) variants. Their tendency to infiltrate surrounding brain structures complicates successful surgery. Reliable markers are required to predict tumor behavior and to establish individualized treatment protocols. METHODS We describe the distribution pattern of CLDN1 in a large cohort of 66 adaCPs, 21 papCPs, and 24 Rathke`s cleft cyst (RCC) cases using immunohistochemistry. CLDN1 mRNA levels were analyzed with qRT-PCR in 33 CP samples. The impact on the migration potential was studied in primary adaCP cell cultures (n = 11) treated with small interfering RNA (siRNA) for CLDN1. Furthermore, CLDN1 distribution patterns and expression levels were compared between invasive (n = 16) and noninvasive (n = 17) tumor groups. RESULTS PapCPs and RCCs exhibited a distinct homogenous and membranous expression pattern, whereas CLDN1 immunoreactivity appeared weaker and more heterogeneous in adaCPs. In the latter cases, whirl-like cell clusters showed complete absence of CLDN1. mRNA analysis confirmed reduced CLDN1 levels in adaCPs versus papCPs. Interestingly, invasive tumors exhibited significantly lower CLDN1 expression compared with noninvasive counterparts regardless of CP subtype. Accordingly, siRNA treatment for CLDN1 altered tumor cell migration in vitro. CONCLUSION CLDN1 represents a novel marker in the differential diagnosis of CP variants and RCCs. Low CLDN1 expression levels correlate with an invasive CP growth pattern and may serve as a prognostic marker.

Direct intraoperative micromethod for hormone measurements of pituitary tissue in Cushing's disease.

BACKGROUND During transsphenoidal surgery (TSS) for Cushings disease, the surgeon depends on experience to find minute adenomas. Cytological slide preparations or frozen sections, even when successful, are not specific concerning the hormone activity. In an attempt to improve accurate localization of minute ACTH adenomas, we evaluated a new intraoperative method of ACTH measurements in adenoma and anterior lobe microsamples. As most ACTH adenomas are monohormonal, the possible benefit of a GH measurement was investigated. METHODS We included pituitary tissue of 32 patients, 22 with Cushings disease and 10 endocrine inactive pituitary adenomas as control. All patients underwent TSS by one surgeon. Preoperative data, intraoperative and perioperative hormone measurements of homogenized, weighed pituitary tissue samples, and histological findings are presented. RESULTS In ACTH adenomas, the median ACTH content was found to be 1,688 ng/mg, minimum 345 ng/mg. The median GH was measured at 36 ng/mg. Anterior lobe tissue contained median 80 ng ACTH/mg, maximum 279 ng/mg. Median GH was 2,200 ng/mg. In hormonally inactive adenomas ACTH was less than 0.1 ng/mg, median GH was 5.5 ng/mg. There was no overlap of ACTH content in the tissues investigated. Therefore, by adopting 300 ng ACTH/mg as a cutoff level, a clear discrimination is given. Additional GH measurements are not necessary. CONCLUSION This new intraoperative method permits a clear differentiation between adenoma and pituitary tissue. In addition to intraoperative cytology and histology, this method can serve as a specific proof that the ACTH adenoma has been identified during surgery. This may be valuable in difficult cases with unclear intraoperative findings, especially after previously negative exploration.

The Value of Intraoperative Cytology During Transsphenoidal Surgery for ACTH-Secreting Microadenoma

Summary Background. Microsurgical selective adenomectomy is the best established method available for the treatment of Cushings disease. However, this surgical method warrants still more efforts to improve the results in minute microadenomas. In this paper the authors evaluate a method of intraoperative cytological investigations during transsphenoidal surgery. Method. Between January 1997 and September 1999, transsphenoidal surgery was performed in 75 patients with the diagnosis of Cushings disease. Fifty-one cases of proven microadenomas were reviewed. Findings. Of 51 cases, 33 tumors were 3 mm or less in diameter, here after called minute adenomas. In 49 of 51 (96.1%) microadenomas, adenoma tissue was identified by intraoperative cytological techniques. Postoperatively, only 35 of 51 ACTH-secreting microadenomas (68.6%) were confirmed by immunostaining methods. This lower percentage was most probably due to the small amount of tissue obtained. Therefore, in 14 cases (including 12 minute adenomas) the presence of the adenoma was only proven by cytological preparation and clinical outcome. The sensitivity of cytological preparations in cases of confirmed Cushings disease was 100%. Interpretation. The method described here was particularly well suited for the intraoperative discrimination and documentation of minute adenomas. Cytological preparation appears to be effective in improving the adenoma finding rate and the surgical outcome in cases of Cushings disease.