Henry Dufour

Gamma knife radiosurgery in the management of cavernous sinus meningiomas

The purpose of this paper was to note a potential source of error in magnetic resonance (MR) imaging. Magnetic resonance images were acquired for stereotactic planning for GKS of a vestibular schwannoma in a female patient. The images were acquired using three-dimensional sequence, which has been shown to produce minimal distortion effects. The images were transferred to the planning workstation, but the coronal images were rejected. By examination of the raw data and reconstruction of sagittal images through the localizer side plate, it was clearly seen that the image of the square localizer system was grossly distorted. The patient was returned to the MR imager for further studies and a metal clasp on her brassiere was identified as the cause of the distortion.A-60-year-old man with medically intractable left-sided maxillary division trigeminal neuralgia had severe cardiac disease, was dependent on an internal defibrillator and could not undergo magnetic resonance imaging. The patient was successfully treated using computerized tomography (CT) cisternography and gamma knife radiosurgery. The patient was pain free 2 months after GKS. Contrast cisternography with CT scanning is an excellent alternative imaging modality for the treatment of patients with intractable trigeminal neuralgia who are unable to undergo MR imaging.The authors describe acute deterioration in facial and acoustic neuropathies following radiosurgery for acoustic neuromas. In May 1995, a 26-year-old man, who had no evidence of neurofibromatosis Type 2, was treated with gamma knife radiosurgery (GKS; maximum dose 20 Gy and margin dose 14 Gy) for a right-sided intracanalicular acoustic tumor. Two days after the treatment, he developed headache, vomiting, right-sided facial weakness, tinnitus, and right hearing loss. There was a deterioration of facial nerve function and hearing function from pretreatment values. The facial function worsened from House-Brackmann Grade 1 to 3. Hearing deteriorated from Grade 1 to 5. Magnetic resonance (MR) images, obtained at the same time revealed an obvious decrease in contrast enhancement of the tumor without any change in tumor size or peritumoral edema. Facial nerve function improved gradually and increased to House-Brackmann Grade 2 by 8 months post-GKS. The tumor has been unchanged in size for 5 years, and facial nerve function has also been maintained at Grade 2 with unchanged deafness. This is the first detailed report of immediate facial neuropathy after GKS for acoustic neuroma and MR imaging revealing early possibly toxic changes. Potential explanations for this phenomenon are presented.In clinical follow-up studies after radiosurgery, imaging modalities such as computerized tomography (CT) and magnetic resonance (MR) imaging are used. Accurate determination of the residual lesion volume is necessary for realistic assessment of the effects of treatment. Usually, the diameters rather than the volume of the lesion are measured. To determine the lesion volume without using stereotactically defined images, the software program VOLUMESERIES has been developed. VOLUMESERIES is a personal computer-based image analysis tool. Acquired DICOM CT scans and MR image series can be visualized. The region of interest is contoured with the help of the mouse, and then the system calculates the volume of the contoured region and the total volume is given in cubic centimeters. The defined volume is also displayed in reconstructed sagittal and coronal slices. In addition, distance measurements can be performed to measure tumor extent. The accuracy of VOLUMESERIES was checked against stereotactically defined images in the Leksell GammaPlan treatment planning program. A discrepancy in target volumes of approximately 8% was observed between the two methods. This discrepancy is of lesser interest because the method is used to determine the course of the target volume over time, rather than the absolute volume. Moreover, it could be shown that the method was more sensitive than the tumor diameter measurements currently in use. VOLUMESERIES appears to be a valuable tool for assessing residual lesion volume on follow-up images after gamma knife radiosurgery while avoiding the need for stereotactic definition.This study was conducted to evaluate the geometric distortion of angiographic images created from a commonly used digital x-ray imaging system and the performance of a commercially available distortion-correction computer program. A 12 x 12 x 12-cm wood phantom was constructed. Lead shots, 2 mm in diameter, were attached to the surfaces of the phantom. The phantom was then placed inside the angiographic localizer. Cut films (frontal and lateral analog films) of the phantom were obtained. The films were analyzed using GammaPlan target series 4.12. The same procedure was repeated with a digital x-ray imaging system equipped with a computer program to correct the geometric distortion. The distortion of the two sets of digital images was evaluated using the coordinates of the lead shots from the cut films as references. The coordinates of all lead shots obtained from digital images and corrected by the computer program coincided within 0.5 mm of those obtained from cut films. The average difference is 0.28 mm with a standard deviation of 0.01 mm. On the other hand, the coordinates obtained from digital images with and without correction can differ by as much as 3.4 mm. The average difference is 1.53 mm, with a standard deviation of 0.67 mm. The investigated computer program can reduce the geometric distortion of digital images from a commonly used x-ray imaging system to less than 0.5 mm. Therefore, they are suitable for the localization of arteriovenous malformations and other vascular targets in gamma knife radiosurgery.

Correlation Between O6-Methylguanine-DNA Methyltransferase and Survival in Inoperable Newly Diagnosed Glioblastoma Patients Treated With Neoadjuvant Temozolomide

PURPOSE This phase II study evaluated the efficacy and safety of a 7-day on/7-day off regimen of temozolomide before radiotherapy (RT) in patients with inoperable newly diagnosed glioblastoma. PATIENTS AND METHODS Patients received temozolomide (150 mg/m2/d on days 1 to 7 and days 15 to 21 every 28 days; 7 days on/7 days off) for up to four cycles before conventional RT (2-Gy fractions to a total of 60 Gy) and for four cycles thereafter or until disease progression. The primary end point was tumor response. Tumor tissue from 25 patients was analyzed for O6-methylguanine-DNA methyltransferase (MGMT) expression. RESULTS Twenty-nine patients with a median age of 60 years were treated, and 28 were assessable for response. Seven (24%) of 29 patients had a partial response, nine patients (31%) had stable disease, and 12 patients (41%) had progressive disease. Median progression-free survival (PFS) time was 3.8 months, and median overall survival (OS) time was 6.1 months. Patients with low MGMT expression, compared with patients with high MGMT expression, had a significantly higher response rate (55% v 7%, respectively; P = .004) and improved PFS (median, 5.5 v 1.9 months, respectively; P = .009) and OS (median, 16 v 5 months, respectively; P = .003). The most common grade 3 and 4 toxicities were thrombocytopenia (20%) and neutropenia (17%). CONCLUSION This dose-dense temozolomide regimen resulted in modest antitumor activity with an acceptable safety profile in the neoadjuvant setting, and expression of MGMT correlated with response to temozolomide. However, this treatment approach seems to be inferior to standard concomitant RT plus temozolomide.

Safety and Efficacy of Temozolomide in Patients With Recurrent Anaplastic Oligodendrogliomas After Standard Radiotherapy and Chemotherapy

PURPOSE Most primary oligodendrogliomas and mixed gliomas (oligoastrocytoma) respond to treatment with procarbazine, lomustine, and vincristine (PCV), with response rates of approximately 80%. However, limited data on second-line treatments are available in patients with recurrent tumors. A novel second-generation alkylating agent, temozolomide, has recently demonstrated efficacy and safety in patients with recurrent glioblastoma multiforme and anaplastic astrocytoma. This study describes the effects of temozolomide in patients with recurrent anaplastic oligodendroglioma (AO) and anaplastic mixed oligoastrocytoma (AOA). PATIENTS AND METHODS Forty-eight patients with histologically confirmed AO or AOA who had received previous PCV chemotherapy were treated with temozolomide (150 to 200 mg/m2/d for 5 days per 28-day cycle). The primary end point was objective response. Secondary end points included progression-free survival (PFS), time to progression, overall survival (OS), safety, and tolerability. RESULTS Eight patients (16.7%) experienced a complete response, 13 patients (27.1%) experienced a partial response (objective response rate, 43.8%), and 19 patients (39.6%) experienced stable disease. For the entire treatment group, median PFS was 6.7 months and median OS was 10 months. For objective responders, median PFS was 13.1 months and median OS was 16 months. For complete responders, PFS was more than 11. 8 months and OS was more than 26 months. Response correlated with improved survival. Temozolomide was safe and well tolerated. Twelve patients developed grade 1/2 thrombocytopenia and three patients developed grade 3/4 thrombocytopenia. CONCLUSION Temozolomide is safe and effective in the treatment of recurrent AO and AOA.

Temozolomide Treatment in Aggressive Pituitary Tumors and Pituitary Carcinomas: A French Multicenter Experience

CONTEXT To date only 18 patients with aggressive pituitary tumors or carcinomas treated with temozolomide have been reported. Increased expression of O6-methylguanine-DNA-methyltranferase (MGMT) has been suggested to predict resistance to temozolomide. OBJECTIVES The objective of the study was to describe the antitumoral efficacy and toxicity of temozolomide in patients with aggressive pituitary tumors or carcinomas and evaluate the possible prognostic value of MGMT promoter methylation and protein expression. PATIENTS Eight patients, five with pituitary carcinomas (three prolactin (PRL) and two ACTH) and three with aggressive pituitary tumors (one PRL and two ACTH), all treated with temozolomide administered orally for four to 24 cycles, were included in our French multicenter study. DESIGN MGMT expression was assessed by immunohistochemistry and MGMT promoter methylation by pyrosequencing. RESULTS Three of the eight patients (two ACTH adenomas and one PRL carcinoma) responded to temozolomide as demonstrated by significant tumor shrinkage and reduced hormone secretion. Three cycles of temozolomide were sufficient to identify treatment-responsive patients. Additional cycles did not improve treatment efficacy in those not responding, even when associated with carboplatin and vepeside. MGMT expression did not predict tumoral response to temozolomide because it was positive in one responder and negative in two nonresponders. Similarly, MGMT promoter methylation (three of seven tumors) did not predict clinical response. Toxicity remained mild in all patients. CONCLUSION Temozolomide treatment may be an effective option for some aggressive pituitary tumors or carcinomas. Response to a trial of three cycles of treatment seems sufficient to identify responders and more reliable than patient MGMT status.

Pineal region tumors and the role of stereotactic biopsy: review of the mortality, morbidity, and diagnostic rates in 370 cases.

OBJECTIVE It is classically considered that the morbidity and mortality rates are greater for stereotactic biopsies of pineal region tumors, compared with tumors in other regions. However, to date, the number of cases studied in the literature has been insufficient to evaluate these parameters and compare them with the morbidity and mortality rates for stereotactic biopsies of tumors located elsewhere. METHODS With the aim of evaluating these parameters, we reviewed 370 stereotactic biopsies of pineal region tumors, from 15 French neurosurgical centers. We statistically verified the absence of heterogeneity of the different French centers with regard to diagnostic, mortality, and morbidity rates. In contrast, statistical heterogeneity was clearly seen for the large stereotactic biopsy series (for all tumor locations) in the literature. RESULTS The mortality rate was 1.3% (5 patients of 370), and 3 patients suffered severe neurological complications. This study is the first to clearly demonstrate that the mortality, morbidity, and diagnostic rates for stereotactic biopsies are not different in the pineal region. CONCLUSION Our conclusion is that stereotactic biopsy must remain a main diagnostic modality for tumors of the pineal region.

Phase II study of temozolomide without radiotherapy in newly diagnosed glioblastoma multiforme in an elderly populations

Currently, the survival of patients age > 70 years with glioblastoma multiforme (GBM) ranges from 4 months to 6 months, although radiotherapy and/or chemotherapy may prolong survival in certain subgroups. Temozolomide is an oral chemotherapeutic agent with efficacy against malignant gliomas and a favorable safety profile. This open‐label, single‐center, Phase II study was designed to evaluate the efficacy and safety of temozolomide as first‐line chemotherapy and exclusive treatment in elderly patients with newly diagnosed GBM.

Long-term Tumor Control and Functional Outcome in Patients with Cavernous Sinus Meningiomas Treated by Radiotherapy with or without Previous Surgery: Is There an Alternative to Aggressive Tumor Removal?

OBJECTIVEWe report the long-term follow-up of 31 patients with cavernous sinus meningiomas who were treated either with surgery and radiotherapy (RT) or with RT alone. This retrospective review was undertaken to compare long-term efficacy and morbidity of RT with or without previous surgery versus complete, aggressive surgical removal. METHODSBetween 1980 and 1997, we performed a retrospective study of 31 patients harboring cavernous sinus meningiomas. The patient group comprised 25 women and 6 men. Patients were divided into two therapeutic categories: patients treated with surgery and RT (Group I, 17 patients) and patients treated with RT alone (Group II, 14 patients). Twenty-five patients (14 in Group I and 11 in Group II) were treated for primary tumors, and 6 patients (3 in Group I and 3 in Group II) were treated for recurrent disease. All three patients who were treated by RT alone at the time of recurrent disease had had previous surgery as initial treatment. Tumor control, treatment morbidity, and functional outcomes were evaluated for all patients. Twenty-eight patients were alive at the time of analysis, with a median follow-up period of 6.1 years. RESULTSThe progression-free survival rate was 92.8% at 10-year follow-up. Only two patients exhibited tumor progression after initial treatment. One of the patients who experienced tumor regrowth 4 years after surgery and RT benefited from additional conventional external beam radiation, and this patient exhibited no evidence of tumor progression at the last follow-up examination 6 years later. Two patients experienced cranial nerve impairment after surgery, and no patients developed late radiation toxicity. Follow-up status as measured by the Karnofsky Performance Scale deteriorated in 7% of patients and was the same or improved in 93% of patients. CONCLUSIONThe results of combined surgery and RT or RT alone indicated a high rate of tumor control and a low risk of complications. Complete aggressive surgical removal of cavernous sinus meningiomas is associated with an increased incidence of morbidity and mortality and does not demonstrate a better rate of tumor control. Conventional external beam radiation seems to be an efficient and safe initial or adjuvant treatment of these lesions, and these findings should serve as a basis for evaluating new alternatives such as radiosurgery or stereotactic RT.

Meningeal hemangiopericytoma: a retrospective study of 21 patients with special review of postoperative external radiotherapy.

OBJECTIVETo specify that postoperative radiotherapy is useful for preventing local recurrence and neuraxis recurrence of surgically treated meningeal hemangiopericytomas. METHODSWe retrospectively studied 21 patients with meningeal hemangiopericytoma who were followed in our department during a 34-year period. In 17 patients, the meningeal hemangiopericytoma was intracranial, and in 4 there was an intradural extramedullary localization. These groups were studied separately. RESULTSOf the 17 patients with intracranial hemangiopericytoma, all underwent surgery; 8 also underwent radiotherapy (5000–6400 rads) (Group I), and 9 did not (Group II). The mortality rate was zero for Group I patients and 55% for Group II. The mean local recurrence rate was 52% (12.5% in Group I and 88% in Group II;P < 0.05). Neuraxis recurrences occurred in two patients in Group II, and none occurred in Group I (P = 0.4). Peripheral metastasis took place in two patients (22%) in Group II and in one patient (12.5%) in Group I (P = 0.5). Of the four patients with intradural extramedullary hemangiopericytoma, all underwent surgery. Two patients received 4000 rads of radiotherapy after intervention. No patient in this group had a recurrence. CONCLUSIONFor patients with intracranial meningeal hemangiopericytoma, surgical removal followed by external radiotherapy reduced the risk of local recurrence. It was not demonstrated that postoperative radiotherapy protected against neuraxis metastasis. Radiotherapy did not protect against peripheral metastasis, which can occur up to several years after the first operation. It appears that radiotherapy after surgery for local or neuraxis recurrence did not avoid further recurrence. Radiosurgery is indicated for recurrent tumors measuring less than 25 mm in greatest diameter. For intradural extramedullary localizations, the value of postoperative radiotherapy is more questionable.

Long-term results of stereotactic radiosurgery in secretory pituitary adenomas.

CONTEXT To date, no study reported long-term follow-up results of gamma knife stereotactic radiosurgery (SR). OBJECTIVE The aim of the study was to determine long-term efficacy and adverse effects of SR in secreting pituitary adenomas. DESIGN We conducted a retrospective study of patients treated by SR in the center of Marseille, France, with a follow-up of at least 60 months. PATIENTS A total of 76 patients were treated by SR for acromegaly (n = 43), Cushings disease (CD; n = 18), or prolactinoma (n = 15) as a primary (n = 27) or adjunctive postsurgical treatment (n = 49). MAIN OUTCOME MEASURES After withdrawal of antisecretory drugs, patients were considered in remission if they had mean GH levels below 2 ng/ml and normal IGF-I (acromegaly), normal 24-h urinary free cortisol, and cortisol less than 50 nmol/liter after low-dose dexamethasone test (CD) or two consecutive normal samplings of prolactin levels (prolactinoma). RESULTS After a mean follow-up of 96 months, 44.7% of the patients were in remission. Mean time to remission was 42.6 months. Twelve patients presented late remission at least 48 months after SR. Two patients with CD presented late recurrence 72 and 96 months after SR. Forty percent of patients treated primarily with SR were in remission. Target volume and initial hormone levels were significant predictive factors of remission in univariate analysis. Radiation-induced hypopituitarism was observed in 23% patients; in half of them, hypopituitarism was observed after a mean time of 48 to 96 months. Twenty-four patients were followed for more than 120 months; rates of remission and hypopituitarism were similar to the whole cohort. CONCLUSIONS SR is an effective and safe primary or adjunctive treatment in selected patients with secreting pituitary adenomas.

Pituitary carcinomas and aggressive pituitary tumours: merits and pitfalls of temozolomide treatment

Pituitary carcinomas are rare, accounting for about 0·2% of all pituitary tumours. They represent a challenge to clinical practice in both diagnosis and treatment. They may present initially as typical pituitary adenomas, with a delayed appearance of aggressive signs, or as aggressive tumours from the outset. Predicting the pituitary tumour behaviour remains difficult: increased mitotic, Ki‐67 and P53 indices might be associated with tumour aggression. The treatment of pituitary carcinomas and aggressive pituitary tumours includes surgery, adjuvant medical treatment, external beam radiotherapy and chemotherapy. Until recently, the treatment of pituitary carcinomas was mainly palliative and did not seem to increase overall survival. Recent case reports have detailed the successful use of temozolomide, an orally administered alkylating agent used to treat malignant gliomas, in the management of pituitary carcinomas and aggressive pituitary tumours. The outcome of treatment might depend on the expression of O 6 ‐methylguanine‐DNA methyltransferase (MGMT), a DNA repair enzyme that potentially interferes with drug efficacy. This review describes the clinical presentation and response to temozolomide in 44 patients with pituitary carcinomas or aggressive pituitary tumours reported in the literature. The results suggest that temozolomide should be considered a drug of major importance in the therapeutic algorithm of aggressive pituitary tumours and pituitary carcinomas. Because of the inconsistency of published data, MGMT expression should probably not be taken as a reason to deny these patients the potential benefit of temozolomide treatment, taking into account the paucity of other available treatments.