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W J Curran

Publications and source records attributed to W J Curran.

At least 55 records · Page 3Linked to original sources
PubMed1998

Patterns of tumor progression after radiotherapy for low-grade gliomas: analysis from the computed tomography/magnetic resonance imaging era.

Postoperative radiotherapy for low-grade gliomas has been shown in retrospective series to improve survival, compared with surgery alone. To determine the proper radiotherapy treatment volume and dose, an understanding of the patterns of failure with current radiotherapy techniques is necessary. We studied 30 consecutive patients who had a pathologic diagnosis of low-grade nonpilocytic glioma treated in our department between 1975 and 1994. Before radiotherapy, 5 patients underwent biopsy, 22 had subtotal resection, and 3 had gross total excision. All had pre- and posttreatment computed tomographic (CT) or magnetic resonance imaging (MRI) scanning. Megavoltage radiotherapy was delivered to shrinking partial (22 patients) or whole-brain (8 patients) fields. Median dose was 59.4 Gy (range, 46.4-64 Gy) in 1.8- to 2-Gy fractions. Median follow-up was 44 months (3-215 months) for the cohort and 105 months for survivors. For the entire series, 5-year overall survival and relapse-free survival rates were 50% and 41%, respectively. Sixteen patients (53%) progressed at a median of 30 months. At the time of failure, 71% (5 of 7) of pathologically evaluated tumors were of high grade. Recurrence originated within the field in all patients. Higher 5-year overall survival and relapse-free survival rates were associated (p < 0.001) with preradiotherapy functional status 1 versus functional status 2 through 4 (60% vs. 0% and 55% vs. 0%, respectively). Seizure as initial presentation was favorable over other symptoms (5-year overall survival, 64% versus 14%; p = 0.057). We conclude that 1) low-grade nonpilocytic gliomas can transform to high-grade lesions after treatment with conventional radiotherapy, 2) recurrence uniformly occurs within the treatment volume, and 3) pretreatment functional status correlates prognostically with survival. The local pattern of failure suggests that radiotherapy dose escalation within conformal fields could improve results.

Adolescent↗
PubMed1998

A generalized film technique for the verification of vertex fields used in the treatment of brain tumors.

With the availability of commercial three-dimensional (3D)-treatment planning systems, more and more treatment plans call for the use of noncoplanar conformal beams for the treatment of brain tumors. However, techniques for the verification of many noncoplaner beams, such as vertex fields which involve any combination of gantry, collimator, and table angles, do not exist. The purpose of this work is to report on the results of an algorithm and a technique that have been developed for the verification of noncoplanar vertex fields used in the treatment of brain tumors. This technique is applicable to any geometric orientation of the beam, i.e., a beam orientation that consists of any combination of gantry, table, and collimator rotations. The method consists of superimposing a central plane image of a correctly magnified vertex field on a lateral or oblique field port film. To achieve this, the 3D coordinates of the projection of the isocenter onto the film for lateral (or oblique) as well as the vertex fields are determined and then appropriately matched. Coordinate transformation equations have been developed that enable this matching precisely. A film holder has been designed such that a film cassette can be secured rigidly along the side rails of the treatment table. The technique for taking a patient treatment setup verification film consists of two steps. In the first step, the gantry, table, and collimator angles for the lateral (or oblique) field are set and the usual double exposures are made; the first exposure corresponds to that of the treatment portal with the isocenter clearly identified and the second one a larger radiation field so that the peripheral anatomy is visible on the film. In the next step, the gantry, table, and collimator angles are positioned for the vertex field and the table is moved laterally and vertically and the film longitudinally to a position that will enable precise matching of the isocenter on the film. A third exposure is then taken with the vertex portal. What is seen on the film is a superposition of a central plane image of the vertex field onto the image of the lateral or oblique field. This technique has been used on 60 patients treated with noncoplanar fields for brain tumors. In all of these cases, the coincidence of the projection of the isocenter for the lateral (or oblique) and the vertex fields was found to be within 3 mm.

Algorithms↗
PubMed1998

Issues in nonoperative management of locally advanced non-small-cell lung cancer.

The challenge for oncologists treating patients with stage III non-small-cell lung cancer (NSCLC) is to optimize a treatment strategy using nonsurgical therapies. The recognition that chemotherapy response rates for patients with previously untreated locally advanced NSCLC are higher than for those with metastatic tumors led to the testing of induction chemotherapy prior to thoracic radiotherapy. The regimen of induction vinblastine and cisplatin followed by standard thoracic radiotherapy is considered by many to be the optimal regimen against which future nonsurgical approaches should be tested. In a trial conducted by the European Organization for the Research and Treatment of Cancer, a significant survival advantage favored daily low-dose cisplatin/radiotherapy and weekly cisplatin/radiotherapy over radiotherapy alone. Presumably, the simultaneous delivery of low-dose cisplatin with radiotherapy enhanced local tumor response, and the use of higher drug doses in the induction regimens deterred the progression of micrometastatic disease. The principal disadvantage of concomitant therapy is the enhancement of normal tissue toxicity, both hematologic and esophageal, resulting in unnecessary patient morbidity and attenuation of radiotherapy and/or chemotherapy delivery. The current phase III Radiation Treatment Oncology Group trial seeks to determine the risk/benefit ratio of concurrent versus sequential delivery of chemoradiotherapy as well as the additional value of oral etoposide in this multimodality regimen. Accrual will be completed in 1998. There is also increasing interest in interdigitating systemic agents that have been established to be more active in metastatic NSCLC than cisplatin/etoposide with thoracic radiotherapy for stage III disease. Phase I/II trials using agents like carboplatin and paclitaxel with thoracic radiotherapy are summarized, as are plans for phase III testing.

Antineoplastic Agents↗
PubMed1998

Radiation-induced toxicities: the role of radioprotectants.

Ionizing radiation has been used to treat many malignancies since the turn of the century. Modern radiotherapeutic techniques have led to increased cure rates and improved local regional control, but the potentially severe and debilitating adverse effects of radiation therapy have not been fully eliminated. Managing radiation-induced toxicities often focuses on treating the symptoms as they manifest. However, preventing these complications is clearly more desirable. Radiation-induced toxicities may be ameliorated in several ways. Dose fractionation was one of the earliest methods recognized to decrease radiation-induced toxicities. Another early method was the use of physical shielding to reduce the area of exposure. Pharmacologic approaches to improving the therapeutic index of radiotherapy fall under two categories: radiosensitizers or radioprotectants. Radiosensitizers are compounds that enhance the sensitivity of tumors to the effects of radiation, but not normal tissue. Radioprotectants such as amifostine function by reducing the effects of radiation on normal cells while maintaining tumor sensitivity. Clinical trials have demonstrated that amifostine can reduce both acute and late radiation-induced toxicities. The development of amifostine has thus resulted in greater tumor control without sacrificing patient well-being. Further investigations are necessary to ensure that patients receive the optimum therapeutic benefit.

Amifostine↗
PubMed1997

A prospective, randomized study addressing the need for physical simulation following virtual simulation.

PURPOSE: To accurately implement a treatment plan obtained by virtual or CT simulation, conventional or physical simulation is still widely used. To evaluate the need for physical simulation, we prospectively randomized patients to undergo physical simulation or no additional simulation after virtual simulation. METHODS AND MATERIALS: From July 1995 to September 1996, 75 patients underwent conformal four-field radiation therapy planning for prostate cancer with a commercial grade CT simulator. The patients were randomized to undergo either port filming immediately following physical simulation or port filming alone. The precision of implementing the devised plan was evaluated by comparing simulator radiographs and/or port films against the digitally reconstructed radiographs (DRRs) for x, y, and z displacements of the isocenter. Changes in beam aperture were also prospectively evaluated. RESULTS: Thirty-seven patients were randomized to undergo physical simulation and first day port filming, and 38 had first day treatment verification films only without a physical simulation. Seventy-eight simulator radiographs and 195 first day treatment port films were reviewed. There was no statistically significant reduction in treatment setup error (>5 mm) if patients underwent physical simulation following virtual simulation. No patient required a resimulation, and there was no significant difference in changes of beam aperture. CONCLUSIONS: Following virtual simulation, physical simulation may not be necessary to accurately implement the conformal four-field technique. Because port filming appears to be sufficient to assure precise and reliable execution of a devised treatment plan, physical simulation may be eliminated from the process of CT based planning when virtual simulation is available.

Computer Simulation↗
PubMed1997

Induction cisplatin/vinblastine and irradiation vs. irradiation in unresectable squamous cell lung cancer: failure patterns by cell type in RTOG 88-08/ECOG 4588. Radiation Therapy Oncology Group. Eastern Cooperative Oncology Group.

PURPOSE: To analyze disease failure patterns by pretreatment characteristics and treatment groups in a prospective randomized trial. METHODS AND MATERIALS: Patients with medically inoperable Stage II, unresectable IIIA and IIIB nonsmall cell lung cancer with KPS > or =70 and weight loss < or =5% were randomized to one of three treatment groups: standard radiation therapy with 60 Gy at 2.0 Gy per day (STD RT), induction chemotherapy with cisplatin 100 mg/m2 days 1 and 29 with vinblastine 5 mg/m2 weekly for 5 weeks followed by 60 Gy at 2.0 Gy per day (CT + RT), or hyperfractionated radiation therapy with 69.6 Gy at 1.2 Gy b.i.d. (HFX RT). Of 490 patients enrolled, 458 were evaluable. Minimum and median periods of observation for this analysis were 4 years and 6 years, respectively. RESULTS: Pretreatment characteristics were equally distributed. Toxicities were previously reported. Median survival rates were 11.4, 13.6, and 12.3 months for STD RT, CT + RT, and HFX RT, respectively (log rank p = 0.05, Wilcoxon p = 0.04). Survivals were 20, 31, and 24% at 2 years, and 4, 11, and 9% at 4 years in the STD RT, CT + RT, and HFX RT groups, respectively. There were no differences in local tumor control rates among the treatments. Patterns of first failure showed less distant metastasis (DM) (other than brain) for CT + RT compared to the RT alone arms (p = 0.04). Within squamous cell carcinoma (SCC), DM (other than brain) rates were 43%, 16%, and 38% in SCC for STD RT, CT + RT, and HFX RT, respectively (p = 0.0015). Patients with peripheral/chest wall lesions were significantly more likely to fail first in the thorax when treated on STD RT compared to CT + RT and HFX RT (p = 0.009). Survival rates were similar among the treatment arms for patients with squamous cell carcinoma. Among patients with nonsquamous cell carcinoma, failure patterns did not differ by treatment group, but survival was significantly better in those who were treated by induction chemotherapy (p = 0.04). CONCLUSION: Patients with squamous cell carcinoma treated on the CT + RT arm had a significant reduction of first DM other than brain, but there was difference in survival. Survival favored CT + RT in nonsquamous carcinoma despite similar failure patterns. Reasons for improved survival with CT + RT in NSCLC are not yet available.

Adenocarcinoma↗
PubMed1997

Will primary central nervous system lymphoma be the most frequent brain tumor diagnosed in the year 2000?

BACKGROUND: There has been a dramatic increase in the diagnosis of primary lymphoma of the brain during the past decade, prompting speculation that it may become the most frequently diagnosed tumor of the central nervous system by the year 2000. The current analysis drew from the updated Surveillance, Epidemiology, and End Results (SEER) database to establish projections for the incidence of brain lymphoma. The study also attempted to determine whether increased incidence rates are attributable to the increasing incidence of acquired immunodeficiency syndrome (AIDS) and whether there is gender or age dependence. METHODS: Primary brain lymphoma case data and population census data for calculating incidence rates for the period 1973-1992 were obtained from the SEER program. In an attempt to determine the contribution of AIDS to the increasing incidence of the disease, separate analyses were performed with and without the inclusion of never married men (a high risk group for the development of AIDS). Separate analyses were also performed within the San Francisco SEER registry because a higher incidence of AIDS-related cancers has been documented in this geographic region. Finally, a piece-wise linear model (using one regression line until 1982 and another regression line from 1982 onward) was used to predict incidence rates for the year 2000. RESULTS: During the period of study, the incidence rates of brain lymphoma increased more than 10-fold, from 2.5 cases per 10 million population in 1973 to 30 in 1991-1992 (chi-square trend, 17.76: P < 0.0001). These increased incidence rates were independent of age and gender. The incidence rates of primary brain lymphoma did not differ significantly when comparing the San Francisco registry with the remainder of the SEER database for any comparison that excluded never married males. However, when the analysis included never married males, a statistically significantly higher incidence rate of primary central nervous system lymphoma was observed among San Franciscans compared with age-matched controls from the remainder of the SEER database. In the year 2000, the projected incidence rate of brain lymphoma would reach 51.1 per 10 million population and 118.2 per 10 million population, with never married men excluded and included, respectively. These incidence rates would still fall below the corresponding projections for glioma and glioblastoma multiforme. CONCLUSIONS: There continues to be a significantly increasing incidence of brain lymphoma that is independent of age and gender. Indirect evidence implicates the AIDS epidemic as a contributor to this trend. Although the rate of increase in the incidence of non-Hodgkin's lymphoma of the brain is higher than for peripheral non-Hodgkin's lymphoma and other glial tumors, brain lymphoma is not projected to surpass glial tumors as the most frequently diagnosed intracranial malignancy by the year 2000.

Age Factors↗
PubMed1997

Palliation of AIDS-related primary lymphoma of the brain: observations from a multi-institutional database.

PURPOSE: To catalogue the presenting symptoms of patients with AIDS who are presumed to have primary central nervous system lymphoma (PCNSL). To document the palliative efficacy of cranial irradiation (RT) relative to the endpoints of complete and overall response for the respective symptoms. METHODS: An analysis of 163 patients with AIDS-related PCNSL who were evaluated at nine urban hospitals was performed. These patients were treated for PCNSL after the establishment of a tissue diagnosis or on a presumptive basis after failing empiric treatment for toxoplasmosis. All patients were treated between 1983 and 1995 with radiotherapy (median dose-fractionation scheme = 3 Gy x 10) and steroids (>90% dexamethasone). Because multiple fractionation schemes were used, prescriptions were converted to biologically effective doses according to the formula, Gy10 = Total Dose x (1 + fractional dose/alpha-beta); using an alpha-beta value of 10. RESULTS: The overall palliative response rate for the entire group was 53%. In univariate analysis, trends were present associating complete response rates with higher performance status (KPS > or = 70 vs. KPS < or = 60 = 17% vs. 5%), female gender (women vs. men = 29% vs. 8%), and the delivery of higher biologically effective doses (BED) of RT (Gy10 > 39 vs. < or = 39 = 20% vs. 5%). In multivariate analysis of factors predicting complete response, both higher KPS and higher BED retained independent significance. A separate univariate analysis identified high performance status (KPS > or = 70 vs. KPS < or = 60 = 71% vs. 47%), and young age (< or = 35 vs. > 35 = 61% vs. 40%) as factors significantly correlating with the endpoint of the overall response. In multivariate analysis, high performance status and the delivery of higher biologically effective doses of irradiation correlated significantly with higher overall response rates. CONCLUSION: Most AIDS patients who develop symptoms from primary lymphoma of the brain can achieve some palliation from a management program that includes cranial irradiation. Young patients with excellent performance status are most likely to respond to treatment. The delivery of higher biologically effective doses of irradiation also may increase the probability of achieving a palliative response.

Acquired Immunodeficiency Syndrome↗
PubMed1997

External beam irradiation for choroid metastases: identification of factors predisposing to long-term sequelae.

PURPOSE: To improve overall quality of life, palliative treatments should attempt to minimize associated complications while effectively controlling specific symptoms. We reviewed our experience treating posterior uveal metastases with external beam radiotherapy (EBRT) to determine the complication rate and to identify the relationship between patient, tumor, or treatment-related factors and the development of ocular complications. METHODS AND MATERIALS: 483 consecutive patients (pts) (578 eyes) were diagnosed with intraocular metastatic disease from solid tumors between 1972-1995. Of these, 233 eyes (188 pts) had lesions of the posterior uveal tract and received EBRT. Median follow-up time was 5.8 months (range: 0.7-170.0 months). Follow-up information regarding the development of complications was documented for 230 eyes. Complete EBRT details were available for 189 eyes. Seventy-two percent of the patients received 30.0-40.0 Gy in 2.0-3.0 Gy fractions. Biologically effective dose (BED) was calculated to allow meaningful comparisons between various fractionation regimens and total doses. Concurrent chemotherapy and/or hormonal therapy was used for 101 eyes (44%). RESULTS: Median BED was 61 Gy3 (range, 6.7-105 Gy3), and 80% of treated eyes received BED 50-70 Gy3. EBRT energies included photons (70%), 60Co (19%), electrons (6%), mixed energies (3%), and orthovoltage (2%). Lens-sparing techniques were used in 136 eyes (71%). At last follow-up 28 eyes (12%) developed one or more significant complications, including cataracts (16 eyes), radiation retinopathy (6 eyes), optic neuropathy (5 eyes), exposure keratopathy (5 eyes), and neovascularization of the iris (4 eyes). Two eyes developed narrow-angle glaucoma, and one of these required enucleation. On univariate analysis, Caucasian race (vs. Black/Hispanic, p = 0.03), increased intraocular pressure at diagnosis (>21 mmHg, p = 0.02), and diagnosis by biopsy (vs. no biopsy, p = 0.03) predisposed toward the development of complications. Factors not correlated with complications included BED (p = 0.18), energy type (p = 0.81), lens-sparing technique (versus whole globe, p = 0.57), and concurrent systemic treatment (p = 0.60). The small number of complications did not support a multivariate analysis. CONCLUSIONS: Despite the employment of a variety of EBRT treatment techniques and the proximity of choroidal metastases to radiosensitive structures, significant complications of palliative EBRT were infrequent. Although complications do occur, they are related to host factors and do not appear to be a function of irradiation parameters. We conclude that the potential benefits of vision and globe preservation after palliative EBRT outweigh the small risk of treatment induced complications.

Adult↗
PubMed1997

Dose estimation to critical organs from vertex field treatment of brain tumors.

PURPOSE: Radiation management of intracranial tumors may require a noncoplanar vertex field that often irradiates the entire length of the body. In view of radiation related risks to the normal tissues dose estimation to the extracranial organs such as the thyroid gland, spinal cord, heart, and genitalia is performed for a vertex field. METHODS AND MATERIALS: A vertex field used clinically was reproduced on an anthropomorphic Rando phantom to measure radiation dose to various organs in the primary beam. Three photon beams (4, 6, and 10 MV), and two high energy electron beams (16 and 20 MeV) were used. Dosimetry was performed with an ion chamber sandwiched between phantom slices at the appropriate positions. All doses were normalized to the target dose at a depth of 5 cm. The effect of the head position was studied by rotating the gantry angle up to +/-20 degrees to mimic the extension and flexion of the head. Theoretical calculation was performed using an exponential best fit to the depth dose table to estimate the dose to various points and compare with the measured dose. RESULTS: The measured normalized dose to the cervical cord, thyroid, heart, and female and male gonads are 60, 36, 16, 2.5, and 1.6%, respectively, for a 6 MV photon beam. The dose from 4 MV and 10 MV are slightly lower and higher, respectively. Doses from electron beams are about a factor of 4-10 lower than those of the photon beams. The measured gonadal dose from the primary beam is <5% of the target dose for all energies used in the study. The actual value, however, is dependent on the body structure, length, and the posture of the patient. A +5 degree head flexion had little effect on the dose to the various parts of the body. The head rotations greater than +/-10 degrees produced relatively lower doses by a factor of 10(-2) to the organs at distances greater than 40 cm from the prescription point. The radiation doses to the different critical organs estimated from the fitted curves are lower than the measured doses up to 35%. CONCLUSIONS: When a vertex field is used for the treatment of the brain tumors, the entire axial length of the body is irradiated which adds to the integral dose. Unlike the scattered and leakage radiation, the primary dose to extracranial critical organs is greater for higher energies. For a 10 MV beam the ovary and testis at a distance of 80 cm and 90 cm may receive a dose of 4.2 and 3%, respectively, of the target dose. The gonadal dose could be quite significant if the entire treatment is delivered using a vertex field. For pediatric and smaller patients, dose to the critical organs at known distances could be estimated from the empirical equation obtained from the measured data. While the risk-benefit ratio is often evaluated and acceptable for treating malignant tumors, the long-term complications need thorough assessment in younger and curable patients. In view of radiation carcinogenesis and genetic burden, dose reduction to critical organs should be considered using a 3D planning system to arrange beams in other nonaxial planes and by considering electron beams for the vertex field.

Brain Neoplasms↗
PubMed1997

Efficient CT simulation of the four-field technique for conformal radiotherapy of prostate carcinoma.

PURPOSE: Conformal radiotherapy of prostate carcinoma relies on contouring of individual CT slices for target and normal tissue localization. This process can be very time consuming. In the present report, we describe a method to more efficiently localize pelvic anatomy directly from digital reconstructed radiographs (DRRs). MATERIALS AND METHODS: Ten patients with prostate carcinoma underwent CT simulation (the spiral mode at 3 mm separation) for conformal four-field "box" radiotherapy. The bulbous urethra and bladder were opacified with iodinated contrast media. On lateral and anteroposterior DRRs, the volume of interest (VOI) was restricted to 1.0-1.5 cm tissue thickness to optimize digital radiograph reconstruction of the prostate and seminal vesicles. By removing unessential voxel elements, this method provided direct visualization of those structures. For comparison, the targets of each patient were also obtained by contouring CT axial slices. RESULTS: The method was successfully performed if the target structures were readily visualized and geometrically corresponded to those generated by contouring axial images. The targets in 9 of 10 patients were reliable representations of the CT-contoured volumes. One patient had 18 mm variation due to the lack of bladder opacification. Using VOIs to generate thin tissue DRRs, the time required for target and normal tissue localization was on the average less than 5 min. CONCLUSION: In CT simulation of the four-field irradiation technique for prostate carcinoma, thin-tissue DRRs allowed for efficient and accurate target localization without requiring individual axial image contouring. This method may facilitate positioning of the beam isocenter and provide reliable conformal radiotherapy.

Humans↗
PubMed1997

Legal history of emergency medicine from medieval common law to the AIDS epidemic.

The early development of legal obligation in emergency medicine is traced through medieval English common law to the first stages of American law after Independence. An identifiable set of legal principles in the nineteenth and early twentieth centuries is described. The movement away from an absence of legal and ethical duties to answer any emergencies, or to offer any emergency services in hospitals, toward a growing demand for access to emergency services in the middle decades of the twentieth century is reviewed. The enactment of Good Samaritan Laws is described, along with other federal and state law reforms. In the modern era, there has been a substantial legal and ethical change to a requirement of extensive duties to operate open-admission emergency services in virtually all acute-care hospitals. The AIDS epidemic is utilized as a case example of expanded legal and ethical duties to offer emergency care in a nondiscriminatory manner to all patients presenting at hospital emergency departments.

Acquired Immunodeficiency Syndrome↗
PubMed1997

Multiple fractionated stereotactic radiotherapy of residual pituitary macroadenomas: initial experience.

OBJECTIVE: We describe our initial experience with fractionated stereotactic radiotherapy (SRT) for the treatment of 19 patients with secretory and nonsecretory pituitary macroadenomas. The primary endpoints of local control and the documentation of any MRI T2-weighted changes in contiguous brain tissues are discussed. METHODS: Between 1/95 and 1/97, 19 patients were planned with the X-Knife 3-D planning system (Radionics, Burlington, Mass., USA) and received a median dose of 46 Gy in daily 2.0-Gy fractions. Treatments were delivered stereotactically with a dedicated 600SR linear accelerator (Varian Corporation, Palo Alto, Calif., USA). Immobilization was achieved with the Gill-Thomas-Cosman relocatable frame. The mean tumor size was 2.24 cm. The mean prescription isodose was 87%. The mean age was 53 years (10 male, 9 female). The mean follow-up time was 10 months (range 1-24 months). The mean optic chiasm and brain stem doses were calculated at 38 and 13 Gy, respectively. All patients were evaluated with pre- and postgadolinum-enhanced MRI scans and Humphrey visual field tests. RESULTS: In the posttreatment period, local control (absence of tumor progression) has been achieved in all of the patients. The treatment was well tolerated in all patients. No acute complications, no visual changes and no T2-weighted MRI or proton density changes were documented in any of the 19 patients. CONCLUSION: These preliminary results suggest that SRT compares favorably with conventional radiotherapy in achieving local control. The doses to the brainstem and the temporal lobes are significantly decreased and at early follow-up no white matter changes are seen on MRI after SRT. The true frequency of grade 1-4 changes are likely underestimated as similar changes often occur in association with tumor edema or after surgery. Given the uncertain neurocognitive significance of the white matter changes associated with treating these benign tumors by conventional radiotherapy, we are currently treating all pituitary adenomas with fractionated SRT to reduce the potential sequelae.

Adenoma↗
PubMed1997

Functional vision is improved in the majority of patients treated with external-beam radiotherapy for choroid metastases: a multivariate analysis of 188 patients.

PURPOSE: Metastatic deposits are the most common intraocular malignancies. We evaluated the efficacy of external-beam radiotherapy (EBRT) in the palliation of posterior uveal metastases in terms of clinically relevant outcomes: functional vision, tumor control, and globe preservation. PATIENTS AND METHODS: Four hundred eighty-three consecutive patients (578 eyes) were diagnosed with intraocular metastatic disease from solid tumors between 1972 and 1995. Of these, 233 eyes (188 patients) had lesions of the posterior uveal tract and received EBRT. Best-corrected visual acuity (VA) was documented pre- and post-EBRT. Visual function was considered excellent if VA < or = 20/50, navigational if 20/60 to 20/200, and legally blind if > or = 20/400. Most patients received 30 to 40 Gy in 2- to 3-Gy fractions to the posterior or entire globe. RESULTS: Fifty-seven percent of all assessable eyes had improved visual function or maintained at least navigational vision following EBRT. Thirty-six percent of legally blind eyes regained useful vision. Ninety-three percent experienced no clinical evidence of tumor progression and the globe preservation rate was 98%. The following characteristics independently predicted improvement to or maintenance of excellent vision on multivariate analysis: excellent vision pre-EBRT (P = .001), age less than 55 years (P = .004), white race (v black/Hispanic) (P = .003), and tumor base diameter less than 15 mm (P < .001). CONCLUSION: EBRT effectively restores and maintains useful vision in patients with choroid metastases, with a globe preservation rate of 98%. Patients less than 55 years with pretreatment VA better than 20/60 and tumor diameter less than 15 mm are most likely to benefit from this therapeutic intervention.

Adult↗
PubMed1997

Stereotactic radiosurgery and radiotherapy: new developments and new directions.

Stereotactic irradiation is a precise method for the delivery of focused radiation beams to small intracranial targets. Treatment can be administered in single or multiple fractions (radiosurgery or stereotactic radiotherapy, respectively). The technology has evolved rapidly because of advances in both hardware and software design. Clinical indications are unfolding through the prospective trial mechanism.

Animals↗