Search Results

You are looking at 1 - 10 of 19 items for

  • Author or Editor: Jay S. Loeffler x
  • Refine by Access: all x
Clear All Modify Search
Full access

Stereotactic radiation treatment for benign meningiomas

Andrew E. H. Elia, Helen A. Shih, and Jay S. Loeffler

✓Meningiomas are the second most common primary tumor of the brain. Gross-total resection remains the preferred treatment if achievable with minimal morbidity. For incompletely resected or inoperable benign meningiomas, 3D conformal external-beam radiation therapy can provide durable local tumor control in 90 to 95% of cases. Stereotactic radiosurgery (SRS) and fractionated stereotactic radiotherapy (SRT) are highly conformal techniques, using steep dose gradients and stereotactic patient immobilization. Stereotactic radiosurgery has been used as an alternative or adjuvant therapy to surgery for meningiomas in locations, such as the skull base, where operative manipulation may be particularly difficult. Stereotactic radiotherapy is useful for larger meningiomas (> 3–3.5 cm) and those closely approximating critical structures, such as the optic chiasm and brainstem. Although SRS has longer follow-up than SRT, both techniques have excellent 5-year tumor control rates of greater than 90% for benign meningiomas. Stereotactic radiotherapy has toxicity equivalent to that of radiosurgery, despite its biased use for larger meningiomas with more complicated volumes. Reported rates of imaging-documented regression are higher for radiosurgery, but neurological recovery is relatively good with both techniques. Stereotactic radiosurgery and fractionated SRT are complementary techniques appropriate for different clinical scenarios.

Restricted access

Radiosurgery and radiotherapy: observations and clarifications

Douglas Kondziolka, L. Dade Lunsford, Jay S. Loeffler, and William A. Friedman

Object. Radiosurgery and radiation therapy represent important but unique treatment paradigms for patients with certain neoplasms, vascular lesions, or functional disorders. The authors discuss their differences.

Methods. Reviewing the authors' experiences shows how the roles of these approaches vary just as their techniques differ. The distinct differences include the method of target localization (intraoperative compared with pretreatment) and irradiation (focused compared with wide-field), their radiobiology (effects of a single high-dose compared with multiple fractions), the physicians and other health personnel involved in the conduct of these procedures (surgical team compared with radiation team), and the expectations that follow treatment. During the last decade, considerable confusion has grown regarding nomenclature, requisite physician training, and the roles of the physician and surgeon. Ten years ago, two task forces on radiosurgery were created by national organizations in neurosurgery and radiation oncology to address these issues of procedural conduct and quality-assurance requirements. At the present time these guidelines are widely ignored. Currently, many patients, payers, and regulatory agencies are bewildered. What are the differences among stereotactic radiosurgery, fractionated radiation therapy, and stereotactic radiation therapy? Radiosurgery is to radiation therapy as microsurgery is to “microtherapy.”

Conclusions. In this report the authors discuss terminology, training, and physician roles in this expanding field.

Restricted access

Accuracy of Stereotaxis

Restricted access

Proton beam for arteriovenous malformations

L. Dade Lunsford

Restricted access

The radium bomb: Harvey Cushing and the interstitial irradiation of gliomas

Michael Schulder, Jay S. Loeffler, Anthony E. Howes, Eben Alexander III, and Peter McL. Black

✓ Harvey Cushing performed over 2000 operations on patients with brain tumors, including 832 for gliomas. He implanted radioactive radium needles, known as a “radium bomb,” in a small number of these patients. He was not impressed with the results and did not pursue this method of treatment in a serious way. The authors present here Cushing's little-known experience with brachytherapy and discuss the reasons for his lack of interest in this technique, despite his advocacy of radiotherapy for certain lesions. An interesting perspective is offered for contemporary neurosurgeons involved in the treatment of brain tumors with cranial irradiation.

Restricted access

Dose—volume prediction of radiation-related complications after proton beam radiosurgery for cerebral arteriovenous malformations

Fred G. Barker II, William E. Butler, Sue Lyons, Ethan Cascio, Christopher S. Ogilvy, Jay S. Loeffler, and Paul H. Chapman

Object. The use of radiosurgery for the treatment of cerebral arteriovenous malformations (AVMs) and other lesions demands an accurate understanding of the risk of radiation-related complications. Some commonly used formulas for predicting risk are based on extrapolation from small numbers of animal experiments, pilot human treatment series, and theoretical radiobiological considerations. The authors studied the incidence of complications after AVM radiosurgery in relation to dose, volume, and other factors in a large patient series.

Methods. A retrospective review was conducted in 1329 patients with AVM treated by Dr. Raymond Kjellberg at the Harvard Cyclotron Laboratory (HCL) between 1965 and 1993. Dose and volume were obtained from HCL records, and information about patient follow up was derived from concurrent clinical records, questionnaires, and contact with referring physicians. Multivariate logistic regression with bootstrapped confidence intervals was used.

Follow up was available in 1250 patients (94%); the median follow-up duration was 6.5 years. The median radiation dose was 10.5 Gy and the median treatment volume was 33.7 cm3. Twenty-three percent of treated lesions were smaller than 10 cm3. Fifty-one permanent radiation-related deficits occurred (4.1%). Of 1043 patients treated with a dose predicted by the Kjellberg isoeffective centile curve to have a less than 1% complication risk, 1.8% suffered radiation-related complications. Actual complication rates were 4.7% for 128 patients treated at Kjellberg risk centile doses of 1 to 1.8%, and 34% for 61 patients treated at risk centile doses of 2 to 2.5%. The fitted logistic model showed that complication risk was related to treatment dose and volume, thalamic or brainstem location, and patient age.

Conclusions. The Kjellberg isoeffective risk centile curve significantly underpredicted actual risks of permanent complications after proton beam radiosurgery for AVMs. Actual risks were best predicted using a model that accounted for treatment dose and volume, lesion location, and patient age.

Restricted access

Pre-irradiation chemotherapy for infants and children with medulloblastoma: a preliminary report

Cynthia S. Kretschmar, Nancy J. Tarbell, William Kupsky, Beverly L. Lavally, Jay S. Loeffler, Lawrence Wolfe, Roy Strand, R. Michael Scott, and Stephen E. Sallan

✓ From March, 1984, through June, 1987, 21 newly diagnosed children with high-risk medulloblastoma (Chang Stage T3 to T4) were treated on a 9-week postoperative, pre-irradiation chemotherapy regimen consisting of vincristine and cisplatin. The children over 2 years old then received radiation therapy. Six infants (aged 6 to 18 months) were maintained on chemotherapy consisting of MOP (nitrogen mustard, vincristine, and procarbazine) until the age of 2 years, at which time they were referred for irradiation. Of 13 children with measurable disease following surgery, five showed a definite response on computerized tomography scans to vincristine and cisplatin (one complete response and four partial responses) and five others showed clear marginal responses. Four of the six infants were disease-free at 19, 32, 35, and 57 months from diagnosis. One infant developed progressive disease at the completion of the vincristine and cisplatin course, and a second infant had progression during MOP administration. Three of the 21 children developed hearing loss within the speech frequencies during cisplatin treatments, but there were no other major toxicities. Fifteen children remained disease-free with a median follow-up period of 35 months (range 19 to 57 months). Chemotherapy given between surgery and radiotherapy may allow for the direct evaluation of a specific drug regimen and permit the postponement of radiation therapy in infants. Pre-irradiation vincristine and cisplatin was well tolerated and effective in shrinking the tumor in most children with medulloblastoma. Such chemotherapy regimens have the potential for extending long-term survival in high-risk children.

Restricted access

Detection of recurrent gliomas with quantitative thallium-201/technetium-99m HMPAO single-photon emission computerized tomography

Paulo A. Carvalho, Richard B. Schwartz, Eben Alexander III, Basem M. Garada, Robert E. Zimmerman, Jay S. Loeffler, and B. Leonard Holman

✓ Deteriorating clinical status after high-dose radiation therapy for high-grade gliomas may be due to radiation changes or may signal recurrent or residual tumor mass. The two conditions cannot be distinguished reliably by computerized tomography (CT) or magnetic resonance (MR) imaging. The authors assessed the ability of sequential thallium-201 chloride (201T1) and technetium-99m hexamethylpropylene amine oxime (99mTc HMPAO) single-photon emission CT (SPECT) to distinguish tumor recurrence from radiation changes after high-dose (≥ 600 cGy) radiation therapy for malignant gliomas. Preoperative tumor/nontumor uptake ratios were analyzed in 32 patients and correlated with the presence of gross tumor at the time of reoperation.

In 12 of 13 patients with 201T1 tumor/scalp ratios of 3.5 or greater, recurrent tumor was present. The authors found 99mTc HMPAO SPECT to be useful for identifying the absence of solid tumor recurrence in patients with low to moderate 201T1 uptake (ratio 1.1 to 3.4) and low perfusion to that site. In 11 of 12 patients with 99mTc HMPAO tumor/cerebellum ratios of 0.50 or less, no recurrent tumor mass was present. Three of seven patients with 201T1 ratios of 3.4 or less and 99mTc HMPAO ratios of 0.51 or more had recurrent tumor found at surgery; thus the test was not predictive in this group. It is concluded that the use of sequential 201T1 and 99mTc HMPAO SPECT accurately identifies the presence of tumor recurrence versus radiation changes in most patients with high-grade astrocytomas who have undergone tumor resection and high-dose radiation therapy.

Restricted access

Treatment of patients with primary glioblastoma multiforme with standard postoperative radiotherapy and radiosurgical boost: prognostic factors and long-term outcome

Dennis C. Shrieve, Eben Alexander III, Peter McL. Black, Patrick Y. Wen, Howard A. Fine, Hanne M. Kooy, and Jay S. Loeffler

Object. To assess the value of stereotactic radiosurgery (SRS) as adjunct therapy in patients suffering from glioblastoma multiforme (GBM), the authors analyzed their experience with 78 patients.

Methods. Between June 1988 and January 1995, 78 patients underwent SRS as part of their initial treatment for GBM. All patients had undergone initial surgery or biopsy confirming the diagnosis of GBM and received conventional external beam radiotherapy. Stereotactic radiosurgery was performed using a dedicated 6-MV stereotactic linear accelerator. Thirteen patients were alive at the time of analysis with a median follow-up period of 40.8 months. The median length of actuarial survival for all patients was 19.9 months. Twelve- and 24-month survival rates were 88.5% and 35.9%, respectively. Patient age and Radiation Therapy Oncology Group (RTOG) class were significant prognostic indicators according to univariate analysis (p < 0.05). Twenty-three patients aged younger than 40 years had a median survival time of 48.6 months compared with 55 older patients who had 18.2 months (p < 0.001). Patients in this series fell into RTOG Classes III (27 patients), IV (29 patients), or V (22 patients). Class III patients had a median survival time of 29.5 months following diagnosis; this was significantly longer than median survival times for Classes IV and V, which were 19.2 and 18.2 months, respectively (p = 0.001). Only patient age (< 40 years) was a significant prognostic factor according to multivariate analysis. Acute complications were unusual and limited to exacerbation of existing symptoms. There were no new neuropathies secondary to SRS. Thirty-nine patients (50%) underwent reoperation for symptomatic necrosis or recurrent tumor. The rate of reoperation at 24 months following SRS was 54.8%.

Conclusions. The addition of a radiosurgery boost appears to confer a survival advantage to selected patients.

Restricted access

Magnetic resonance image—directed stereotactic neurosurgery: use of image fusion with computerized tomography to enhance spatial accuracy

Eben Alexander III, Hanne M. Kooy, Marcel van Herk, Marc Schwartz, Patrick D. Barnes, Nancy Tarbell, Robert V. Mulkern, Edward J. Holupka, and Jay S. Loeffler

✓ Distortions of the magnetic field, such as those caused by susceptibility artifacts and peripheral magnetic field warping, can limit geometric precision in the use of magnetic resonance (MR) imaging in stereotactic procedures. The authors have routinely found systematic error in MR stereotactic coordinates with a median of 4 mm compared to computerized tomography (CT) coordinates. This error may place critical neural structures in jeopardy in some procedures. A description is given of an image fusion technique that uses a chamfer matching algorithm; the advantages of MR imaging in anatomical definition are combined with the geometric precision of CT, while eliminating most of the anatomical spatial distortion of stereotactic MR imaging.

A stereotactic radiosurgical case is presented in which the use of MR localization alone would have led to both irradiation of vital neural structures outside the desired target volume and underdose of the intended target volume. The image fusion approach allows for the use of MR imaging, combined with stereotactic CT, as a reliable localizing technique for stereotactic neurosurgery and radiosurgery.