-
[show abstract]
[hide abstract]
ABSTRACT: Recent observational studies have established progression and recurrence rates of pituitary adenomas. However, it is still unknown how individual pituitary adenomas grow over years and whether growth kinetics follow a distinct growth model. The objective of this study was to define a growth model for non-functioning pituitary adenomas.
Fifteen patients who had five or more serial high-quality examinations with magnetic resonance images or computerized tomography scans were identified among 216 patients with non-functioning pituitary adenomas. Tumour volumes were assessed using a stereological method based on the Cavalieri principle. Tumour growth during the observation period was analysed and different growth models were fitted to the data.
Fifteen pituitary adenomas (12 recurrent tumours and 3 newly diagnosed tumours) were longitudinally observed during a median observation period of 7.4 years (range: 2.3-11.9 years). Growth kinetics could be described either by an exponential growth model (nine patients) or by a logistic model (five patients) with initial exponential growth followed by deceleration of growth. One tumour remained unchanged in size during the observation period. None of the adenomas showed accelerated growth during the observation period. Overall, the linear growth model was not suitable to describe the growth kinetics of non-functioning pituitary adenomas.
Our study shows that growth of pituitary adenomas can be described by distinct growth models. Knowledge of growth dynamics has implications for clinical practice and helps to adjust scanning protocols for follow-up investigations.
European Journal of Endocrinology 04/2008; 158(3):287-94. · 3.42 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Schwannomas originating within the sella turcica are extremely rare. We describe the clinical, radiological and intraoperative findings of a patient with an intrasellar and suprasellar schwannoma. Gross total tumour removal was performed by a trans-sphenoidal approach. Perivascular or ectopic Schwann cells, lateral nerve plexus within the cavernous sinus, as well as Schwann cells from small nerve twigs of the dura are some of the current histopathological hypotheses for the origin of these lesions.
British Journal of Neurosurgery 11/2005; 19(5):432-8. · 0.88 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The cell cycle-dependent nuclear antigen Ki-67 is related to growth potential in a variety of tumors. Elevated expression of Ki-67 was previously shown in recurrent pituitary adenomas; however, it has remained unclear whether this expression is related to the growth velocity or invasive behavior of these tumors. The aim of this study was to determine the correlation of Ki-67 antigen expression, growth velocity, and invasiveness in nonfunctioning pituitary adenomas.
Between April 1998 and April 2002, 23 patients with nonfunctioning pituitary adenomas who had participated in an observation period in which multiple computerized tomography and magnetic resonance imaging studies had been performed were surgically treated in our department. Tumor volumes were assessed using a stereological method based on the Cavalieri principle. The growth rate was calculated for each patient. Expression of Ki-67 antigen was examined using the monoclonal antibody MIB-1. The assessed growth velocity of the adenomas was best described by a linear growth model. The correlation between Ki-67 expression and growth rate was highly significant. Rapidly growing adenomas (> 0.07% daily increase in size) were found to have a Ki-67 labeling index (LI) exceeding 1.5%, whereas all five adenomas with a very slow growth rate (< 0.02% daily increase in size) had a Ki-67 LI lower than 1.5%. No correlation was found between the growth rate and the invasive character of the adenomas.
Expression of Ki-67 antigen is significantly correlated to the growth velocity of pituitary adenomas. Invasive behavior is a feature independent of proliferative activity. The extent of Ki-67 expression is helpful for clinical decision making and routine assessment of Ki-67 is recommended during the histopathological workup of pituitary adenomas.
Journal of Neurosurgery 10/2003; 99(4):674-9. · 2.96 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Isolated fungal granulomas originating within the sphenoid sinus are extremely rare in immunocompetent patients. In their symptoms and morphological appearance, these lesions may be mistaken for pituitary tumors. We report such a case and review the literature.
A 74-year-old man presented with a 3-week history of Cranial Nerve III paresis. The patient had a long-term history of snuff abuse. Computed tomography demonstrated a space-occupying lesion of the sellar and sphenoid sinus region with displacement of the cavernous sinus.
The lesion was operated on via a transnasal-transsphenoidal approach. After the sphenoid sinus was opened, mucus extruded spontaneously, and a brownish, crumbly mass was found and removed. The lesion had completely eroded the sella and clivus. Histological analysis revealed numerous Aspergillus hyphae. Postoperatively, the IIIrd cranial nerve paresis resolved completely within a few days. No systemic fungal infection was found in extensive serological studies. There was no evidence of immunosuppression.
Fungal granuloma must be included in the differential diagnosis of lesions in the sellar region, even in nonimmunosuppressed patients. Early diagnosis and transsphenoidal extirpation is crucial with this potentially life-threatening disease.
Neurosurgery 05/2003; 52(4):955-8; discussion 958-9. · 2.79 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Increased pulsatility of blood flow in the basal cerebral arteries recorded with the use of transcranial Doppler sonography (TCD) corresponds to increased intracranial pressure (ICP) to near the level of the diastolic arterial blood pressure. We describe the case of a 39-year-old woman who developed acute reduction in consciousness, anisocoria, gaze deviation, and right-sided hemiparesis 2 days after resection of a relapsed astrocytoma. MRI revealed only a moderate enlargement of the ventricles, but TCD revealed highly pulsatile waveforms of all basal cerebral arteries, showing a biphasic pattern with diastolic backflow. This pattern was interpreted as a massive increase in ICP with imminent danger of cerebral circulatory arrest corresponding to acute malresorptive hydrocephalus. External cerebrospinal fluid drainage was immediately undertaken, revealing excessive ICP of more than 50 cm H(2)O. Twenty-four hours after this intervention, both the ICP and the Doppler waveforms had returned to normal. This case illustrates the usefulness of TCD for diagnosing a critical but potentially reversible acute increase in ICP with imminent cerebral circulatory arrest.
Journal of Clinical Ultrasound 31(6):324-7. · 0.81 Impact Factor
