Transsphenoidal microsurgery for Cushing disease. A report of 216 cases

We report cumulative results of the transsphenoidal microsurgical treatment of Cushing disease in 221 patients: 173 patients had selective adenomectomy, 25 had total hypophysectomy, 6 had partial hypophysectomy, and 12 had exploration only. Five patients were excluded from analysis because intraoperative technical difficulties precluded exposure of the pituitary gland. The selection of candidates for transsphenoidal exploration was based on endocrinologic criteria. Magnetic resonance imaging was the preferred radiologic test. Selective venous sampling of adrenocorticotropic hormone further refined the diagnosis when endocrinologic and radiologic procedures were not definitive. Remission of disease was achieved in 164 of 216 (76%) patients analyzed (95% CI, 69 to 81). Among patients with histologic confirmation of adenomas, the percentage having remission was significantly higher (P less than 0.001) in patients with microadenomas than in patients with macroadenomas and in patients with intrasellar adenomas than in patients with extrasellar extension of their adenoma or perforation of the sellar floor by adenoma (P less than 0.001). Five patients had an ectopic source of adrenocorticotropic hormone secretion. Two patients had diffuse pituitary hyperplasia. Complications occurred in 9.3% of the patients, including two deaths that were apparently unrelated to surgery (CI, 5.4 to 13). The results indicate that transsphenoidal surgery is the preferred treatment for most patients with Cushing disease.

The pituitary "incidentaloma"

PURPOSE

To review evidence related to sellar masses that might be found incidentally on various radiologic procedures, including their differential diagnosis and recommendations for their evaluation and treatment.

DATA IDENTIFICATION

An English-language literature search using bibliographic reviews of textbooks and review articles.

STUDY SELECTION

Articles were selected on the basis of providing data on the autopsy prevalence of sellar masses, the radiologic and endocrinologic evaluation of such masses, and the prognostic aspects of pituitary adenomas.

DATA EXTRACTION

Twelve studies relating autopsy findings, 6 studies describing radiologic characteristics, and 26 articles reviewing various endocrine aspects of pituitary adenomas were evaluated.

RESULTS OF DATA SYNTHESIS

Pituitary adenoma is the most common incidental sellar mass. Scanning techniques are of great importance in differentiating the pituitary adenoma from other mass lesions. Autopsy and radiologic studies suggest that microadenomas (less than 10 mm in diameter) may be present in 10% to 20% of the population but that macroadenomas (greater than 10 mm in diameter) are quite rare. Hormone oversecretion by an adenoma may be asymptomatic but, when present, is very helpful in the differential diagnosis.

CONCLUSIONS

For adenomas found to be hypersecreting, therapy is as indicated for that specific tumor type. If there is no evidence of hormone oversecretion from microadenomas, we suggest a conservative approach with repeat scanning done at yearly intervals, initially, and subsequently less frequently. Macroadenomas, because they have already indicated some propensity for growth, should either be surgically removed or, if completely asymptomatic, followed closely with repeat scans at 6- to 12-month intervals.

Metastasis to the base of the skull: clinical findings in 43 patients

We studied 43 patients with metastases to the base of the skull to determine whether clinical symptoms localized the lesions accurately. We identified five clinical syndromes: orbital, parasellar, middle fossa, jugular foramen, and occipital condyle. The orbital and parasellar syndromes were characterized by frontal headache, diplopia, and first-division trigeminal sensory loss. Proptosis occurred with the orbital but not the parasellar syndrome. The middle-fossa syndrome was characterized by facial pain or numbness. The jugular foramen syndrome was characterized by hoarseness and dysphagia, with paralysis of the ninth through eleventh cranial nerves. The occipital condyle syndrome was characterized by unilateral occipital pain and unilateral tongue paralysis.

Pituitary metastasis: incidence in cancer patients and clinical differentiation from pituitary adenoma

Symptomatic pituitary metastases are uncommon and may be difficult to differentiate from pituitary adenomas. In order to ascertain the incidence of pituitary tumors in cancer patients and to characterize the clinical presentation of pituitary metastases, we reviewed the clinical experience with these tumors at Memorial Sloan-Kettering Cancer Center (MSKCC) during the period 1976-1979 and a recent series of 500 consecutive autopsies in which the pituitary fossa and gland were examined. In the clinical series, a histologic diagnosis was made in three of five patients. Radiologic evaluation, including polytomography and computed tomography, did not reliably distinguish metastasis from adenoma, but the clinical syndromes were distinctive. In the autopsy series, pituitary metastases were found in 3.6% of cases, pituitary adenomas in 1.8%.

Resection of suprasellar tumors by using a modified transsphenoidal approach. Report of four cases

Generally accepted contraindications to using a transsphenoidal approach for resection of tumors that arise in or extend into the suprasellar region include a normal-sized sella turcica, normal pituitary function, and adherence of tumor to vital intracranial structures. Thus, the transsphenoidal approach has traditionally been restricted to the removal of tumors involving the pituitary fossa and, occasionally, to suprasellar extensions of such tumors if the sella is enlarged. However, conventional transcranial approaches to the suprasellar region require significant brain retraction and offer limited visualization of contralateral tumor extension and the interface between the tumor and adjacent structures, such as the hypothalamus, third ventricle, optic apparatus, and major arteries. In this paper the authors describe successful removal of suprasellar tumors by using a modified transsphenoidal approach that circumvents some of the traditional contraindications to transsphenoidal surgery, while avoiding some of the disadvantages of transcranial surgery. Four patients harbored tumors (two craniopharyngiomas and two hemangioblastomas) that arose in the suprasellar region and were located either entirely (three patients) or primarily (one patient) within the suprasellar space. All patients had a normal-sized sella turcica. Preoperatively, three of the four patients had significant endocrinological deficits signifying involvement of the hypothalamus, pituitary stalk, or pituitary gland. Two patients exhibited preoperative visual field defects. For tumor excision, a recently described modification of the traditional transsphenoidal approach was used. Using this modification, one removes the posterior portion of the planum sphenoidale, allowing access to the suprasellar region. Total resection of tumor was achieved (including absence of residual tumor on follow-up imaging) in three of the four patients. In the remaining patient, total removal was not possible because of adherence of tumor to the hypothalamus and midbrain. One postoperative cerebrospinal fluid leak occurred. Postoperative endocrinological function was worse than preoperative function in one patient. No other new postoperative endocrinological or neurological deficits were encountered. This study demonstrates the feasibility of using a modified transsphenoidal approach for resection of certain suprasellar, nonpituitary tumors.

Pituicytoma: a distinctive low-grade glioma of the neurohypophysis

Pituicytoma is a rare, poorly characterized tumor of the sella and suprasellar region that is distinct morphologically from other local tumors and is thought to be derived from neurohypophyseal pituicytes. Clinical data, neuroimaging studies, and microsections were reviewed from nine such low-grade gliomas. Immunostains for glial, neuronal, and proliferation markers were performed on all nine tumors and six control neurohypophyses. Three tumors were studied ultrastructurally. Six men and three women, age 30 to 83 years (mean, 48 years), presented with visual symptoms, headache, or hypopituitarism. Magnetic resonance images showed solid, discrete, contrast-enhancing masses, four within the sella and five in the suprasellar space. The tumors consisted of sheets and/or fascicles of plump spindle cells with slightly fibrillar cytoplasm and slightly pleomorphic, oval-to-elongate nuclei with pinpoint nucleoli. Extracellular mucin was prominent in one tumor. Rosenthal fibers, granular bodies, and Herring bodies (granular axonal dilatations characteristic of the normal neurohypophysis) were lacking. Mitoses were rare or absent. MIB-1 labeling indices were low (0.5-2%). Tumor cells were strongly reactive for vimentin and S-100 protein, variably positive for glial fibrillary acidic protein, and nonreactive for synaptophysin and neurofilament protein. Cytoplasm varied in electron density and contained intermediate filaments. Neither meningothelial nor ependymal features were noted. Two tumors recurred at 20 and 26 months after subtotal resection, but none of the six completely resected tumors have done so. Pituicytomas are discrete, largely noninfiltrative low-grade gliomas of the sellar region that occur in adults. Their histologic appearance is distinct from pilocytic and ordinary, infiltrative astrocytomas. The distinction between pituicytoma and normal neurohypophysis is aided by the latter's content of axons, Herring bodies, and perivascular anucleate zones rich in axonal terminations. Although curable by total excision, subtotal resection can be associated with recurrence.

Zygomatic approach for lesions in the interpeduncular cistern

Lesions in the interpeduncular cistern include basilar tip aneurysms, craniopharyngiomas, and chordomas. The surgical approach to these lesions presents a special technical problem, particularly when they are located high in the interpeduncular fossa. For the purpose of minimizing brain retraction and achieving excellent exposure within the interpeduncular cistern, the authors have developed a new surgical technique which involves detachment of the zygomatic arch. The patient is placed in the supine position with the head rotated 45 degrees to the contralateral side and tilted down 30 degrees so that the surgeon can see into the interpeduncular cistern obliquely from below. The zygomatic arch of the temporal bone as well as a portion of the lateral orbital rim (the posterior ridge of the frontal process of the zygomatic bone) is removed to expose the anterior temporal base. With posterior retraction of the temporal lobe, the arachnoid membranes covering the Sylvian stem are opened in a retrograde fashion until the tentorial edge is sufficiently exposed. The posterior communicating artery and the optic tract are elevated to enter the interpeduncular cistern, after which the oculomotor nerve is dissected free of its surrounding arachnoid membranes and displaced posteroinferiorly. Two patients with basilar tip aneurysms were operated on with this zygomatic approach, and a subtemporal modification of the zygomatic approach was used to treat a craniopharyngioma and a chordoma in two other patients. The procedure is described and a short description of its clinical use is given.

Benign intracranial hypertension

Ninety percent of these 120 patients with BIH were women and were obese. Headache was present in almost all patients and visual symptoms occurred in 35%. There was no neurologic abnormality other than visual loss in these patients followed up to 10 years. Twenty-five percent spontaneously remitted after the initial LP and the others required repeated LP, steroids, or surgical procedures. Thirteen of 15 patients who did not remit spontaneously or respond to repeated LP improved dramatically in 3 to 4 days on prednisone or dexamethasone. Complications of BIH include recurrence of the syndrome, visual impairment and development of the empty sells syndrome. Recurrence rate was 10% and relapses always occurred in the first 12 months. Visual acuity impairment or inferior nasal quadrant field defect occurred in 2% of patients. In only two patients was there a sudden decrease in visual acuity which did not improve with any therapy. There was no way to predict subsequent visual impairment.

Suprasellar meningiomas: the effect of tumor location on postoperative visual outcome

The authors reviewed 38 cases of suprasellar meningioma to determine the correlation between tumor site and postoperative visual outcome. Progressive visual loss, the most frequent initial complaint (94.7%), occurred over a mean of 24 1/2 months, was most often unilateral (18 patients) or bilateral but asymmetrical (14 patients), and was severe (20/200 vision or worse) in 23 patients; 24 patients had visual field abnormalities. Computerized tomography or magnetic resonance studies clearly delineated the lesions but did not appear to permit earlier diagnosis. Eleven patients had tumors limited to the tuberculum sellae; the tumor extended from the tuberculum sellae onto the planum sphenoidale in nine patients, into one optic canal in eight, onto the diaphragma sellae in seven, and onto the medial sphenoid wing in three. Patients with tumors affecting the optic canal had severe unilateral visual loss more often than those with tumors at other sites. Tumors limited to the tuberculum sellae were most often completely resected; postoperative recovery of vision was also most frequent in patients with tumors at this site. Tumors involving the diaphragma sellae or the medial sphenoid wing were least often completely removed and most likely to be associated with postoperative visual deterioration. Overall, 42% of patients had improved vision postoperatively, 30% remained unchanged, and 28% were worse. After a mean follow-up period of 38 months, 24 patients are doing well, four have significant visual disability, and three are blind or doing poorly. Two patients died of causes unrelated to their tumor. Three patients have had tumor recurrence.

Radiation therapy for primary intracranial germ-cell tumors

PURPOSE

To evaluate the diagnosis, therapy, and survival of patients with intracranial germ-cell tumors. To define the role of prophylactic craniospinal irradiation and chemotherapy necessary to impact on survival.

METHODS AND MATERIALS

Forty-eight patients with surgically confirmed or suspected primary intracranial germ-cell tumors treated at UCSF between 1968-1990 were reviewed. Thirty-four patients had a pathologic diagnosis, including 24 germinomas, 3 malignant teratomas, 2 choriocarcinomas, 1 embryonal carcinoma, 1 endodermal sinus tumor, and 3 mixed tumors. Information obtained included histology, location, cerebrospinal fluid (CSF) cytology, alpha-fetoprotein (AFP), and beta-human chorionic gonadotropin (B-HCG), metastatic evaluation, radiation details, survival, and sites of failure. Minimum follow-up time was 2 years and ranged to a maximum of 24 years, with a median of 8 years.

RESULTS

Median age at diagnosis was 16 years with 36 males and 12 females. Ten of 32 patients had elevated B-HCG at diagnosis; 6 of 29 had elevations of AFP. Cerebrospinal fluid cytology was negative in 35 of 36 patients evaluated; myelography or spinal MRI was positive in only 1 of 31 patients studied. Five-year actuarial disease-free survival after irradiation was 91% for germinomas, 63% for unbiopsied tumors, and 60% for nongerminoma germ-cell tumors with doses of 50-54 Gy to the local tumor site with or without whole-brain or whole-ventricular irradiation. Routine prophylactic cranio-spinal axis irradiation was not given with a spinal only failure rate of 2%. Eleven of 48 patients have expired, with an actuarial 5-year survival rate of 100% for germinomas, 79% for nonbiopsied tumors, and 80% for nongerminoma germ-cell tumors.

CONCLUSION

With complete diagnostic craniospinal evaluation, spinal irradiation is not necessary. Cure rates for germinomas are excellent with irradiation alone. Multidrug chemotherapy is necessary with irradiation for nongerminoma germ-cell tumors. Histology is the most important prognostic factor; therefore, all patients should have surgical conformation of their diagnosis so that appropriate treatment can be given.

Epithelial cystic lesions of the sellar and parasellar region: a continuum of ectodermal derivatives?

Cystic epithelial lesions of the sellar and parasellar region are classified on the basis of histology and location into Rathke's cleft cysts, epithelial cysts, epidermoid cysts, dermoid cysts, and craniopharyngiomas. A retrospective review of the clinical presentation, radiological findings, and histology was performed on 19 such lesions, and a survey of the literature pertinent to the classification, clinical presentation, and embryology of these lesions was conducted. Presentation was nonspecific and not predictive of histology. Imaging studies were generally useful in distinguishing these tumors, with the exception of Rathke's cleft cysts, suprasellar epidermoid cysts, and craniopharyngiomas, which frequently could not be differentiated. On microscopic examination, most lesions fit into distinct categories; however, overlap was common among all and some could not be definitively categorized by histological criteria. Evidence supportive of an ectodermal ancestry for sellar and parasellar epithelial-lined cystic lesions is presented. Based on the current findings and a review of the literature, it is suggested that these lesions represent a continuum of ectodermally derived cystic epithelial lesions.

Pineal and suprasellar germinomas. Results of radiation treatment

The results of radiation treatment of 52 patients with a tumor in the pineal region or a suprasellar germinoma are analyzed. The overall 5-year survival rate was 59%. Ten patients in whom initial biopsy confirmed pineal germinoma were all alive 2 to 121 months from diagnosis, although two developed meningeal seeding at 2 and 7 months. Twelve of 15 patients 25 years old or younger with an unbiopsied tumor in the pineal region were alive 12 to 225 months after irradiation, with a 5-year survival rate of 81%. In comparison only five of 16 patients older than 25 years with a pineal region tumor survived, a 5-year survival rate of 37%. This marked age dependence in survival rates was attributed to a high proportion of germinomas in the younger patients and gliomas in the older patients.

Cushing's disease associated with an intrasellar gangliocytoma producing corticotrophin-releasing factor

A 58-year-old woman had Cushing's disease with elevated plasma adrenocorticotrophin and an intrasellar tumor. Light microscopy showed that the tumor was a gangliocytoma containing immunoreactive corticotrophin-releasing factor accompanied by pituitary corticotroph hyperplasia. Ultrastructural examination identified an intimate association and desmosomal attachments between interdigitating cell processes of neurons and corticotrophs. It is suggested that Cushing's disease was due to the effect of corticotrophin-releasing factor on corticotrophs; this case represents a syndrome supporting the concept that, in some patients, Cushing's disease may have a hypothalamic origin.

Tumors of the pineal and suprasellar region: Childrens Cancer Study Group treatment results 1960--1975: a report from Childrens Cancer Study Group

Tumors of the pineal and suprasellar region form a rare and interesting group of lesions with germinomas accounting for over 50% of all lesions in this anatomic region. The Brain Tumor Committee of Childrens Cancer Study Group (CCSG) recently surveyed all CCSG member institutions to determine treatment parameters and assess the techniques. A total of 140 patients were seen during the period from 1960 to 1975; 118 patients were evaluable, having adequate treatment records. One hundred and one patients were less than 30 years of age with a 2:1 male predominance. Thirty-six of the 57 biopsied patients (63%) were found to have germinomas. The survival of patients in the germinoma group (72%) was comparable to that of the patients without biopsy (71%). The overall survival rate for all patients (biopsied and unbiopsied) was 65% with follow-up times ranging from 2 to 15 years. Nine patients developed spinal cord metastases (8%), two of whom also had simultaneous primary recurrence; none of these patients had received adjunctive spinal irradiation.

Selective extradural anterior clinoidectomy for supra- and parasellar processes. Technical note

Removal of the anterior clinoid process (ACP) facilitates radical removal of tumors or radical neck clipping of aneurysms in the supra- and parasellar regions by providing a wide operative exposure of the internal carotid artery (ICA) and the optic nerve and by reducing the need for brain retraction. Over a period of 3 years, anterior clinoidectomy was performed in 40 patients, 30 of whom harbored aneurysms (18 of the ICA and 13 of the basilar artery [one patient had two aneurysms]) and 10 of whom had tumors (four large pituitary tumors, four craniopharyngiomas, and two sphenoid ridge meningiomas). The ACP was removed extradurally in 31 cases and intradurally in nine cases. Extradural clinoidectomy was performed in all cases of pituitary adenoma and craniopharyngioma and in most cases of basilar artery aneurysm. Intradural clinoidectomy was performed in two cases of ICA-ophthalmic artery aneurysm, two cases of ICA-posterior communicating artery aneurysm, two cases of ICA cavernous aneurysm, one case of basilar artery aneurysm, and two cases of sphenoid ridge meningioma. The outcome was satisfactory in all patients, except for one patient who underwent clipping of a basilar tip aneurysm and suffered a thalamic and midbrain infarction. Three patients who underwent extradural clinoidectomy suffered a postoperative diminution of visual acuity or a visual field defect on the side of the clinoidectomy. These deficits may have been caused either by drilling of the ACP or by other operative manipulation of the optic nerve. Cerebrospinal fluid rhinorrhea, which required reoperation, occurred in one patient. The authors' experience suggests that the extradural technique of ACP removal is easier and less time consuming than the intradural one and provides better operative exposure. It can be used routinely in treating lesions in the supra- and parasellar regions.

Surgical management of suprasellar meningioma. Part 1: The influence of tumor size, duration of symptoms, and microsurgery on surgical outcome in 101 consecutive cases

A consecutive series of 101 cases of suprasellar meningioma has been reviewed. Most of the patients were between 40 and 60 years of age, and women predominated in all age groups. Visual impairment was the most common admitting complaint and visual field defect the most common finding. Symmetrical visual field defects were noted in 22 cases, while the remaining 79 cases had either asymmetrical binocular involvement or only monocular defects. All patients underwent craniotomy with the operating microscope being used in 33 cases. Mortality and partial resection rates were lower and overall outcome was better in patients with tumors 3 cm or less in size and a duration of symptoms of 2 years or less. Use of the operating microscope also appeared to lower the mortality rate and improve the overall outcome; however, no effect on postoperative visual improvement was noted.

Microsurgical removal of suprasellar meningiomas

The authors report 17 cases of large suprasellar meningiomas operated on during the 2-year period from February 1982 through March 1984. The tumors ranged from 4 to 9 cm in diameter. These patients presented with severe visual loss (4 were blind) and optic atrophy or papilledema. These tumors were noteworthy in their encroachment against and around the carotid arteries and optic nerves laterally, as well as against the hypothalamus with extension into the interpeduncular cistern and frontal fossa. Advanced microsurgical technique assisted in total removal of all tumor tissue with preservation of vital structures. There were three deaths: two from pulmonary embolism and one from gastrointestinal hemorrhage. The surgical technique for the total removal of these very large tumors is described.

Radiation-induced intracranial malignant fibrous histiocytoma

An autopsy case of radiation-induced intracranial malignant fibrous histiocytoma (fibroxanthosarcoma) is reported. The tumor developed in the region of the sella turcica 11 years after high dose radiotherapy of a chromophobe adenoma of the pituitary. The tumor had infiltrated the base of the brain as well as the base of the skull. Metastases were not found. The tumor was composed of an admixture of bizarre fibroblasts, histiocytes and giant cells, xanthoma cells and siderophages, with a storiform fibrous stroma. This appears to be the first documented instance of a malignant fibrous histiocytoma occurring intracranially after local x-irradiation.

Postoperative improvement in visual function in patients with tuberculum sellae meningiomas: results of the extended transsphenoidal and transcranial approaches

Object

Recently, extended transsphenoidal surgery (ETSS) has become an alternative to transcranial surgery (TCS) for suprasellar meningiomas, although the relative benefits of ETSS have yet to be established. To evaluate the effectiveness of ETSS, the authors analyzed surgical outcomes of TCS and ETSS.

Methods

During a 12-year period, 28 patients with meningiomas arising from the tuberculum sellae underwent tumor removal at Kinki University Hospital. The first 12 patients underwent TCS, and the remaining 16 underwent ETSS. In the TCS group, the optic canal on the approach side was unroofed in all cases. In the ETSS group bilateral optic canals were opened, and the dural and bone defects of the skull base were repaired using abdominal fascia and hydroxyapatite cement. In half of the cases, lumbar drainage of cerebrospinal fluid (CSF) was also performed.

Results

In a retrospective analysis of this consecutive series of patients, improvement in visual acuity and intraoperative blood loss were significantly better in the ETSS group (p = 0.010 and p = 0.011, respectively), whereas improvement in visual field defects, operative times, and the tumor removal rate were not significantly different between the two groups. Nonvisual surgical complications such as CSF leakage (one patient) and infarction of a perforating artery (three patients) were observed in the TCS group. In the ETSS group, CSF leakage (two patients), anosmia (two patients), and infarction of a perforating artery (two patients) were observed.

Conclusions

Given the encouraging results in improvement in visual acuity, ETSS may be acceptable for the treatment of tuberculum sellae meningiomas.

Transsphenoidal decompression of the optic nerve and chiasm. Visual results in 62 patients

A review of recent experience with transsphenoidal for lesion in and about the sella turcica establishes the value of this approach for the management of patients which visual loss. The lesions encountered consisted of pituitary adenoma in 45 cases, craniopharyngioma in 10 cases, and miscellaneous tumours involving the sella in the remaining seven cases. Sixty of the 62 patients in this series had quantitative determination of preoperative and postoperative visual status; after surgery, vision was improved in 81%, unchanged in 11%, and worse in 5%. Two patients (3%) died during the immediate postoperative period before their visual status could be evaluated.