- Email: [email protected]
1011 Poster Proton three-dimensional radiotherapy and radiosurgery of intracranial targets: new clinical program at the Dubna proton therapy facility
$296 Friday/Saturday, 20-2l September 2002
Material and Methods: Forty three patients treated with postoperative radiotherapy were studied. There were 14 women and 29 men aged 16-63 years in analysed group. Thirty three of them had astrocytomas or oligoastrocytomas grade I-Ill, there was also meningioma, adenoma, oligodendroglioma and gliosarcoma confirmed in surgical specimens. All patients had been irradiated using 3D conformal non-coplanar techniques. Total dose of EBI was 60 Gy given in 2 Gy fractions. All patients were examined in MRI/MRS system (Elscint 2T Prestige) at least 6 months after completing EBI. None had evidence of disease at that time. MRS were acquired using a single voxel double-spin echo PRESS sequence. Relative intensities of the signals due to N-acetyl asparaginian (NAA), choline/creatin (Cho/Cre), choline/Nacetyl asparaginian (Cho/NAA), mio-lnositol (ml), lactate(Lac), lipids (Lip) were obtained. Spectra in three voxels positioned distantly from tumor bed in maximum, medium and the lowest dose areas according to isodose radiotherapy treatment plan were analysed and compared, Results: There were significant, dose-dependent differences in NAA, Cho/Cre, Cho/NAA concentration in analysed brain tissue areas, Conclusions: MR spectroscopy seems to be useful tool in monitoring of late brain tissue response to radiation. 1008
Poster
Survival of glioblastoma patients post-radiation related to presenting symptoms, brain site and treatment variables p. Yui/el-, 3, R. Cook 1, M. Biggs 1, N. Little 1, M, Tran2, O. Dent3 1Royal North Shore Hospital of Sydney, Radiation Oncology, Sydney, Australia 2Liverpool Hospital, The Simpson Centre for Health Services Research, Sydney, Australia 3University of Sydney, Surgery, Sydney, Australia Purpose: To evaluate survival times post-radiation in patients with glioblastoma multiforme stratified in respect of tumour location, degree of surgery, age and presenting symptoms. Methods and materials: The records of 117 patients completing cranial radiation within the period 1993-1998 were reviewed in this retrospective study, Major presenting symptoms ( seizure, headache, weakness, headache, dysphasia, visuaf, speech, loss of consciousness and confusion) were coded as were tumour sites (frontal, temporal, parietal, occipital, midline and posterior fossa). Other parameters assessed included side of brain, ECOG scores pre- and post-treatment, age, and degree of surgery. Statistical evaluation was undertaken by univariate and multivariate analyses to identify factors leading to survival greater than 6 months and 10 months, Results: The median survival for the group post-radiation was 10 months, Patients older than 60 years (the median age) had inferior survival compared to those younger. As expected those undergoing excision or extensive debulking showed improved survival compared to lesser degrees of surgery with such patients being 3 times more likely to survive >6 months (P<0.05). Patients with frontal lobe tumours showed superior survival with temporal lobe and midline tumours having the poorest outcome. Patients presenting with loss of consciousness, seizure (OR=4.36, 95%C1=1.16, 6.31), speech disability or dysphasia showed superior survival times (OR=10.89, 95%C1=1.14, 2.11) compared to those with weakness and paresis, headache, or memory loss and confusion. Those receiving greater than 5000cGy radiation showed improved survival to patients receiving less than 5000 cGy. Conclusions: The survival data presented reveals improved outcomes for younger and fitter patients particularly if more radical surgery is undertaken with higher dose radiation. This study reveals new data in respect of outcomes based on tumour site and symptoms at presentation. It is postulated that patients presenting with acute signs and symptoms have earlier investigations and scans being referred earlier for treatment. Conversely those with more subtle signs have a longer period without detection thus compromising surgical and radiotherapeutic intervention. The poor outcome of temporal lobe lesions may be related to tumour bulk, medial extension and challenges in offering high dose radiation to an anatomically difficult and sensitive site.
1009 Poster Long term results of radiotherapy in paediatric brain stem tumours A. Skowronska-Gardas. M. Chojnacka, K. Pedziwiatr Centre of Oncology, Radiotherapy Department, Warsaw, Poland Background: Long term results of RT in brain-stem tumours in children are poor, and few patients survive more than 5 years. The purpose of this study was to evaluate treatment results and toxicity of long term survivors of RT. Material and methods: From 1982 till 1995, 95 children, aged 2-15 years,
Posters
with diagnosis brain stem tumour were treated with RT in our department. Histopathological diagnosis was established in 13 patients (astrocytoma LG in 9, astrocytoma HG in 1, glioma nonspecified in 2). In 2 children subtotal, in 3 partial surgery and in 8 biopsy only was performed. Chemotherapy before RT in 15 children was applied. Sixty seven patients were treated with hyperfractionated and 28 with conventionally fractionated RT. Results: Up to now 76 patients (80%) died, mostly due to local progression of disease, in 4 metastases in CNS were observed. Nineteen children (20%) are still living. Five patients are without any treatment related seqelae, 5 have minor school difficulties and one has a seizure disorder. In 6 patients we observe hearing toss, and 7 require hormonal treatment due to hypophisis insufficiency. Conclusions: Long term survival of children with brain stem tumours in our study was 20 %, and it is still non satisfying result Of treatment of this disease. The high frequency of treatment related seqelae as hearing loss and hypophisis insufficiency indicate a need of modern treatment planning method, which spares radiosensitive structures as hypophisis and middle ear. 1010 Poster Initial results of the treatment of pituitary adenoma in cav-
ernous sinus with linac accelerator-based stereotactic irradiation N. Ova 1, Y. Negoro 1, H. Sai 1, J. Takahashi2, N. Hashimoto2, N. Araki 1, K. Takayama 1, M. Hiraoka 1 1Kyoto University, Department of Therapeutic Radiology and Oncology, Kyoto, Japan 2Kyoto University, Department of Neurosurgery, Kyoto, Japan Recurrent or residual pituitary adenomas in cavernous sinus are difficult to treat by surgical intervention. The purpose of this study is to evaluate the initial outcome and toxicity of the treatment of pituitary adenoma using Linac-based stereotactic radiosurgery (SRS) or stereotactic radiotherapy (SRT). Between September 1998 and November 2000, 14 patients with pituitary adenoma were treated with linac accelerator-based stereotactic irradiation (SRI). The adenoma was ACTH producing in 3 patients, GH producing in 4 patients, and non-functioning in 7 patients. All patients underwent transsphenoidal and/or transcranial resection prior to SRI, and were treated with SRI for recurrent or residual disease in cavernous sinus. The tumor volume ranged 0.5-3.9 ml for functioning and 1.3-18.4 ml for nonfunctioning adenomas, respectively. In principle, SRS was performed, unless the tumor-optic pathway distance was less than 4 mm. The prescribed dose to 80% of the isodose was 14-20 Gy in SRS and 28.8-45 Gy in 12-15 fractions for SRT. CT and/or MR images were used for target determination. Treatment plans were optimized using 5-9 non-coplanar arcs and a collimator of 15-40 mm in diameter. The follow-up time was 14-40 (median 33) months. No tumor regrowth was observed in the 14 cases. Tumor size was decreased in 3 of the 7 non-functioning adenomas 5-9 months after SRI, while the other 11 cases showed no significant tumor size regression. Among the 7 functioning adenomas, only one case with an ACTH producing adenoma, which received 20 Gy SRS, showed continuous decrease in baseline ACTH level during the follow-up of 40 months. In the other 6 cases of functioning adenomas, the ACTH or GH secretion remained persistent for 19-36 (median 28) months after SRI. The dose to optic pathway was limited to less than 8 Gy in SRS or 45 Gy in 15 fractions in SRT, and no visual disorders was observed. In one of the 14 patients, hormonal replacement was newly initiated after treatment. There was no significant difference in outcome and toxicity between SRS and SRT. In conclusion, it seeme~ that-SRI .for pituitary adenomas in cavernous sinus is safe and effective, at least in terms of tumor growth suppression. However, considering the relatively low probability of hormone control (1/7) in the present series, further dose escalation more than 20 Gy in SRS or more than 45 Gy in SRT are recommended particularly for functioning adenomas, although the longer follow-up would be necessary. 101:1
Poster
Proton three-dimensional radiotherapy and radiosurgery of intracranial targets: new clinical program at the Dubna proton therapy facility Y, Luchin, Y. Budyashov, E. Cherevatenko, V. Gaevsky, A. /g/in, A. Molokanov, G. Mytsin, S. Shvidky, Y. Traschenko, V. Zorin Joint Institute for Nuclear Research, Nuclear Prob, Proton Radiation Therapy and Radiosurgery Center, Moscow, Russian Federat Intracranial lesions are the most suitable target locations for conformal proton radiation therapy and radiosurgery.
Posters
Specialized proton procedure room is equipped with horizontal proton beam line with energy of 155 MeV. Beam has up to 8x8-cm rectangular shape. Ridge filters with plateau region 2.5-4.5 cm are used for Bragg peak extention. Patient positioner is the treatment chair with 4 degrees of freedom. System for target alignment and beam centration includes orthogonal laser beams and X-ray tube for introscopic alignment. Films of the skull during treatment are double exposed by X-ray and treatment proton beam. We are using three-dimensional treatment planning system 'qPN" that has been developed at the Loma Linda University Medical Center (CA, USA) by D. Miller. The system was modified to incorporate the Dubna proton beams. Treatment plans also have been duplicated with local planning system. After individual mask manufacturing treatment-planning CT has been performed. Physician outlines target, critical structures, and alignment bone landmarks. 3D structure models are calculated by "TPN". Three to six beams located at the axial plane are calculated. Beams features are individual shape with muityleaf collimators and beam's-eye-view function, complex shape boluses to conform distal contour of the beam to the target shape. Digital reconstructed radiographs (DRRs) with projection of target, isocenter and bone landmarks were calculated and printed. Alignment Rxfilms were compared with DRRs during irradiation sessions. This is first experience in Russia of using 3D-treatment planning and beam formation for proton radiation therapy, Since April 2001 to December 2001, 16 patients with 20 targets received proton conformal radiation therapy or radiosurgery at JINR. 203 proton fractions have been delivered. There were 9 meningiomas, 4 malignant gliomas, 3-brain metastasis, and 1 AVM Total equivalent doses were calculated by the linear-quadratic formula and were 56-60 GyE+a/b to the target margin. Early results demonstrated that developed technique of irradiation allows precise delivering of proton dose to the target volume. Follow-up studies demonstrated that one metastasis completely disappeared, one glioblastoma shows gradual decreasing in size during 6 months post treatmerit, and another malignant glioma shows localized planning necrosis exactly at the predetermined place. Meningiomas and AVM need longer follow-up. 1012 Poster
Prognostic factors in glioblastoma multiforme. Potential role of hemoglobin level prior to radiotherapy K. Odrazka1, J. Petera 1, T. Koh/ova1, M. Do/eze/1, M. Vacu/ikova1, M. Zouhar 1, V, Ma/ek2, V. Hobza2,/. Latt2, E. Cermakova3 1Charles University Hospital, Dept. of Onco/ogy & Radiotherapy, Hradec Kra/ove, Czech Republic 2Charles University Hospital, Dept. of Neurosurgery, Hradec Kralove, Czech Republic 3Charles University Medical School, Dept. of Medical Biophysics, Hradec Kralove, Czech Republic Purpose: To evaluate prognostic factors in patients with glioblastoma multiforme (GBM) treated with postoperative or primary radiotherapy. Methods: From 1989 to 2000, a total of 100 patients underwent irradiation as part of their initial treatment for GBM. All patients had undergone surgery or biopsy followed by conventional external beam radiotherapy (RT). Eighty-five patients who received the planned curative dose of irradiation (60 Gy in 30 fractions) were analyzed for the influence of prognostic factors, 73/85 (86%) of patients were given postoperative RT, while 12/85 (14%) of patients were primarily treated with RT after biopsy, Results: The median overall survival was 10 months (range, 3-49), the 1and 2- year survival rates were 42% and 5%, respectively. Univariate analysis (log-rank test) revealed age up to 55 years (p<0.001), pre-RT hemoglobin (Hb) level over 12 g/alL (p=0.009), and pre-RT dose of dexamethasone up to 2 mg/day (p=O.006) to be associated with prolonged survival. At multivariate analysis (Cox's proportional hazards regression), younger age (p<0.001), higher Hb level (p=0.003), and a favourable tumor location (no evidence of corpus callosum, basal ganglia or brainstem involvement) (p=0.036) were identified as significant prognostic factors for overall survival. The median survival for patients with Hb level over 12 g/dL was 12 months compared to 7.5 months for those with lower Hb level. Contingencytable statistics (chi-square test) showed no significant differences for the two Hb groups in the distribution of age (p=0.178) and tumor location (p=l). We suggest that anemia may further increase the existing intratumoral hypoxia, thus making GBM even more resistant to RT. Conclusions: Our results indicate that Hb level prior to RT for GBM can influence prognosis. This finding deserves further evaluation,
Friday/Saturday, 20-21 September 2002 $297
1013
Poster
Development of treatment strategy of children with malignant intracranial tumors during the last decade of 20th c e n t u r y . A single center experience J. Marls, M. Chanova, B. Malinova, J. Koutecky UniversityHospital Motol, Pediatric Oncology, Prague, Czech Republic Objective: To RFS and OS for children with newly diagnosed malignant brain tumors where after surgery further conservative treatment was administered (radiotherapy and chemotherapy). Methods: During nineties of 20th century two protocols were used in majority of children with brain tumors: "8 in 1" and PNET/SIOP III protocol. The combination "8 in 1" was the treatment for 49 children (medutoblastoma 18, astrocytoma - 12, brain stem tumor - 10, ependymoma - 5, carcinoma 2, kraniopharyngeoma - 1, ependymoma - 1), med. age was 7,1 yrs. After surgery all children were irradiated up to 30 Gy on the whole craniospinar axis with boost of 20 Gy on the tumor area. After completion of radiotherapy all children received six courses of "Eight in One day chemotherapy" or till the time of tumor progression. Forty five children of this group was evaluated. In 1993 a PNET/SIOP III protocol was launched - 44 children were treated according this schedule. Median age was 9,0 yrs. Diagnoses inciuded medulloblastoma (42) and PNET (2). Complete removal of the tumor was performed in 21 pts, biopsy Or subtotal removal 24 pts. Chemotherapy was started after surgery and after then irradiation (30 Gy on craniospinat axis with boost of 20 Gy on the tumor). Forty two children was evaluated. All children treated with SlOP protocol were subdivided into three groups: I. - children where the tumor was completely resected (18) and there were no evidence of metastases, II. children with residual tumor (20) greater than 1 cm2, Ill. children with spread of disease within CNS (4). Results: In the "8 in 1" group 24 children (53 %) had recurrence of disease in reed. period of 7,1 mths and all relapsed children died. Only 21 pts. are followed in CR for approx. 8 yrs+ In the SlOP protocol group RFS at 1, 3 and 5 yrs were 79%, 52% and 43% respectively, OS at 1, 3 and 5 yrs were 81%, 60% and 45%. RFS for the children from the group I at 1, 3 and 5 yrs were 78%, 67% and 56%, OS at 1,3 and 5 yrs were 78%, 72% and 67%. Group II: RFS at 1, 3 and 5 yrs were 70%, 40% and 35%, OS at 1, 3 and 5 yrs were 70%, 50% and 40%. Group Ill: only one child is alive 3,5 yrs after the surgery. Conclusions: The crucial prognostic factor in children with malignant intracranial tumor is complete removal of the tumor and no evidence of leptomenigeal spread of disease. SlOP protocol improved the treatment results but longer follow up of this group is necessary. 1014
Poster
Stereotactic radiosurgery in essen - A database as tool for scientific workup of treatment results and quality control M. Attassi, M.K. Koemer, F. Guntrum, M.H. Seegenschmiedt Alfried-Krupp-Krankenhaus, Radioonkologie, Strahlentherapie und Nuklearmedizi,Essen, Germany Purpose: With growing acceptance of stereotactic radiotherapy among referring doctors and patients, more institutions are performing stereotactic radiosurgery (SRS) or fractionated stereotactic radiosurgery (SRT) in Germany. Guidelines of the RTOG define the dose homogeneity in stereotactic treatment planing volumes. However, no general accepted criteria exist regarding indication, recording of side effects, follow up and treatment outcome. We propose a common data pool open to collaborating clinics for better quality control and easier scientific work up especially in rare entities. Patients and methods: A stereotactic treatment database was designed to collect anonymised patient data, sex and age, diagnosis, planning parameters preceding and concomitant therapy and follow up including quality of life. Special attention was set to recording op potential side effects and treatment outcome. Representative MRI scans were digitally registered. Results: A new stereotactic treatment facility was build up in in early 2000 in the Alfried-Krupp-Krankenhaus, Essen, Germany. Beginning in 5/2000 up to 03/2002 a total of 108 patients (47 F; 61 M) were treated. Of these patients 63 (63%) had SRS and 36 (36%) had SRT. Median age was 59 (27-91) years. The diagnoses were mainly metastases and malignant brain tumors (74%) followed by benign diseases (26%), like menigeomas, arteriovenous-malformations and vestibular schwannomas. The ratio between the volume within prescribed isodoses and the target volumes were within the recommended range (RTOG-guidelines). Grade 3 and grade 4 acute and delayed side effects were seen in 4 cases (3,6% of SRS, 2,8 of SRT-treatments). Follow up is still short for most of the patients with ranges of I to 21 months. The presented data will be updated monthly. Conclusion: We present a new database as a tool for better quality control of stereotactic treatment according to RTOG guidelines. Regional clinics with SRS or SRT facilities are invited to contribute their own patients data.
Material and Methods: Forty three patients treated with postoperative radiotherapy were studied. There were 14 women and 29 men aged 16-63 years in analysed group. Thirty three of them had astrocytomas or oligoastrocytomas grade I-Ill, there was also meningioma, adenoma, oligodendroglioma and gliosarcoma confirmed in surgical specimens. All patients had been irradiated using 3D conformal non-coplanar techniques. Total dose of EBI was 60 Gy given in 2 Gy fractions. All patients were examined in MRI/MRS system (Elscint 2T Prestige) at least 6 months after completing EBI. None had evidence of disease at that time. MRS were acquired using a single voxel double-spin echo PRESS sequence. Relative intensities of the signals due to N-acetyl asparaginian (NAA), choline/creatin (Cho/Cre), choline/Nacetyl asparaginian (Cho/NAA), mio-lnositol (ml), lactate(Lac), lipids (Lip) were obtained. Spectra in three voxels positioned distantly from tumor bed in maximum, medium and the lowest dose areas according to isodose radiotherapy treatment plan were analysed and compared, Results: There were significant, dose-dependent differences in NAA, Cho/Cre, Cho/NAA concentration in analysed brain tissue areas, Conclusions: MR spectroscopy seems to be useful tool in monitoring of late brain tissue response to radiation. 1008
Poster
Survival of glioblastoma patients post-radiation related to presenting symptoms, brain site and treatment variables p. Yui/el-, 3, R. Cook 1, M. Biggs 1, N. Little 1, M, Tran2, O. Dent3 1Royal North Shore Hospital of Sydney, Radiation Oncology, Sydney, Australia 2Liverpool Hospital, The Simpson Centre for Health Services Research, Sydney, Australia 3University of Sydney, Surgery, Sydney, Australia Purpose: To evaluate survival times post-radiation in patients with glioblastoma multiforme stratified in respect of tumour location, degree of surgery, age and presenting symptoms. Methods and materials: The records of 117 patients completing cranial radiation within the period 1993-1998 were reviewed in this retrospective study, Major presenting symptoms ( seizure, headache, weakness, headache, dysphasia, visuaf, speech, loss of consciousness and confusion) were coded as were tumour sites (frontal, temporal, parietal, occipital, midline and posterior fossa). Other parameters assessed included side of brain, ECOG scores pre- and post-treatment, age, and degree of surgery. Statistical evaluation was undertaken by univariate and multivariate analyses to identify factors leading to survival greater than 6 months and 10 months, Results: The median survival for the group post-radiation was 10 months, Patients older than 60 years (the median age) had inferior survival compared to those younger. As expected those undergoing excision or extensive debulking showed improved survival compared to lesser degrees of surgery with such patients being 3 times more likely to survive >6 months (P<0.05). Patients with frontal lobe tumours showed superior survival with temporal lobe and midline tumours having the poorest outcome. Patients presenting with loss of consciousness, seizure (OR=4.36, 95%C1=1.16, 6.31), speech disability or dysphasia showed superior survival times (OR=10.89, 95%C1=1.14, 2.11) compared to those with weakness and paresis, headache, or memory loss and confusion. Those receiving greater than 5000cGy radiation showed improved survival to patients receiving less than 5000 cGy. Conclusions: The survival data presented reveals improved outcomes for younger and fitter patients particularly if more radical surgery is undertaken with higher dose radiation. This study reveals new data in respect of outcomes based on tumour site and symptoms at presentation. It is postulated that patients presenting with acute signs and symptoms have earlier investigations and scans being referred earlier for treatment. Conversely those with more subtle signs have a longer period without detection thus compromising surgical and radiotherapeutic intervention. The poor outcome of temporal lobe lesions may be related to tumour bulk, medial extension and challenges in offering high dose radiation to an anatomically difficult and sensitive site.
1009 Poster Long term results of radiotherapy in paediatric brain stem tumours A. Skowronska-Gardas. M. Chojnacka, K. Pedziwiatr Centre of Oncology, Radiotherapy Department, Warsaw, Poland Background: Long term results of RT in brain-stem tumours in children are poor, and few patients survive more than 5 years. The purpose of this study was to evaluate treatment results and toxicity of long term survivors of RT. Material and methods: From 1982 till 1995, 95 children, aged 2-15 years,
Posters
with diagnosis brain stem tumour were treated with RT in our department. Histopathological diagnosis was established in 13 patients (astrocytoma LG in 9, astrocytoma HG in 1, glioma nonspecified in 2). In 2 children subtotal, in 3 partial surgery and in 8 biopsy only was performed. Chemotherapy before RT in 15 children was applied. Sixty seven patients were treated with hyperfractionated and 28 with conventionally fractionated RT. Results: Up to now 76 patients (80%) died, mostly due to local progression of disease, in 4 metastases in CNS were observed. Nineteen children (20%) are still living. Five patients are without any treatment related seqelae, 5 have minor school difficulties and one has a seizure disorder. In 6 patients we observe hearing toss, and 7 require hormonal treatment due to hypophisis insufficiency. Conclusions: Long term survival of children with brain stem tumours in our study was 20 %, and it is still non satisfying result Of treatment of this disease. The high frequency of treatment related seqelae as hearing loss and hypophisis insufficiency indicate a need of modern treatment planning method, which spares radiosensitive structures as hypophisis and middle ear. 1010 Poster Initial results of the treatment of pituitary adenoma in cav-
ernous sinus with linac accelerator-based stereotactic irradiation N. Ova 1, Y. Negoro 1, H. Sai 1, J. Takahashi2, N. Hashimoto2, N. Araki 1, K. Takayama 1, M. Hiraoka 1 1Kyoto University, Department of Therapeutic Radiology and Oncology, Kyoto, Japan 2Kyoto University, Department of Neurosurgery, Kyoto, Japan Recurrent or residual pituitary adenomas in cavernous sinus are difficult to treat by surgical intervention. The purpose of this study is to evaluate the initial outcome and toxicity of the treatment of pituitary adenoma using Linac-based stereotactic radiosurgery (SRS) or stereotactic radiotherapy (SRT). Between September 1998 and November 2000, 14 patients with pituitary adenoma were treated with linac accelerator-based stereotactic irradiation (SRI). The adenoma was ACTH producing in 3 patients, GH producing in 4 patients, and non-functioning in 7 patients. All patients underwent transsphenoidal and/or transcranial resection prior to SRI, and were treated with SRI for recurrent or residual disease in cavernous sinus. The tumor volume ranged 0.5-3.9 ml for functioning and 1.3-18.4 ml for nonfunctioning adenomas, respectively. In principle, SRS was performed, unless the tumor-optic pathway distance was less than 4 mm. The prescribed dose to 80% of the isodose was 14-20 Gy in SRS and 28.8-45 Gy in 12-15 fractions for SRT. CT and/or MR images were used for target determination. Treatment plans were optimized using 5-9 non-coplanar arcs and a collimator of 15-40 mm in diameter. The follow-up time was 14-40 (median 33) months. No tumor regrowth was observed in the 14 cases. Tumor size was decreased in 3 of the 7 non-functioning adenomas 5-9 months after SRI, while the other 11 cases showed no significant tumor size regression. Among the 7 functioning adenomas, only one case with an ACTH producing adenoma, which received 20 Gy SRS, showed continuous decrease in baseline ACTH level during the follow-up of 40 months. In the other 6 cases of functioning adenomas, the ACTH or GH secretion remained persistent for 19-36 (median 28) months after SRI. The dose to optic pathway was limited to less than 8 Gy in SRS or 45 Gy in 15 fractions in SRT, and no visual disorders was observed. In one of the 14 patients, hormonal replacement was newly initiated after treatment. There was no significant difference in outcome and toxicity between SRS and SRT. In conclusion, it seeme~ that-SRI .for pituitary adenomas in cavernous sinus is safe and effective, at least in terms of tumor growth suppression. However, considering the relatively low probability of hormone control (1/7) in the present series, further dose escalation more than 20 Gy in SRS or more than 45 Gy in SRT are recommended particularly for functioning adenomas, although the longer follow-up would be necessary. 101:1
Poster
Proton three-dimensional radiotherapy and radiosurgery of intracranial targets: new clinical program at the Dubna proton therapy facility Y, Luchin, Y. Budyashov, E. Cherevatenko, V. Gaevsky, A. /g/in, A. Molokanov, G. Mytsin, S. Shvidky, Y. Traschenko, V. Zorin Joint Institute for Nuclear Research, Nuclear Prob, Proton Radiation Therapy and Radiosurgery Center, Moscow, Russian Federat Intracranial lesions are the most suitable target locations for conformal proton radiation therapy and radiosurgery.
Posters
Specialized proton procedure room is equipped with horizontal proton beam line with energy of 155 MeV. Beam has up to 8x8-cm rectangular shape. Ridge filters with plateau region 2.5-4.5 cm are used for Bragg peak extention. Patient positioner is the treatment chair with 4 degrees of freedom. System for target alignment and beam centration includes orthogonal laser beams and X-ray tube for introscopic alignment. Films of the skull during treatment are double exposed by X-ray and treatment proton beam. We are using three-dimensional treatment planning system 'qPN" that has been developed at the Loma Linda University Medical Center (CA, USA) by D. Miller. The system was modified to incorporate the Dubna proton beams. Treatment plans also have been duplicated with local planning system. After individual mask manufacturing treatment-planning CT has been performed. Physician outlines target, critical structures, and alignment bone landmarks. 3D structure models are calculated by "TPN". Three to six beams located at the axial plane are calculated. Beams features are individual shape with muityleaf collimators and beam's-eye-view function, complex shape boluses to conform distal contour of the beam to the target shape. Digital reconstructed radiographs (DRRs) with projection of target, isocenter and bone landmarks were calculated and printed. Alignment Rxfilms were compared with DRRs during irradiation sessions. This is first experience in Russia of using 3D-treatment planning and beam formation for proton radiation therapy, Since April 2001 to December 2001, 16 patients with 20 targets received proton conformal radiation therapy or radiosurgery at JINR. 203 proton fractions have been delivered. There were 9 meningiomas, 4 malignant gliomas, 3-brain metastasis, and 1 AVM Total equivalent doses were calculated by the linear-quadratic formula and were 56-60 GyE+a/b to the target margin. Early results demonstrated that developed technique of irradiation allows precise delivering of proton dose to the target volume. Follow-up studies demonstrated that one metastasis completely disappeared, one glioblastoma shows gradual decreasing in size during 6 months post treatmerit, and another malignant glioma shows localized planning necrosis exactly at the predetermined place. Meningiomas and AVM need longer follow-up. 1012 Poster
Prognostic factors in glioblastoma multiforme. Potential role of hemoglobin level prior to radiotherapy K. Odrazka1, J. Petera 1, T. Koh/ova1, M. Do/eze/1, M. Vacu/ikova1, M. Zouhar 1, V, Ma/ek2, V. Hobza2,/. Latt2, E. Cermakova3 1Charles University Hospital, Dept. of Onco/ogy & Radiotherapy, Hradec Kra/ove, Czech Republic 2Charles University Hospital, Dept. of Neurosurgery, Hradec Kralove, Czech Republic 3Charles University Medical School, Dept. of Medical Biophysics, Hradec Kralove, Czech Republic Purpose: To evaluate prognostic factors in patients with glioblastoma multiforme (GBM) treated with postoperative or primary radiotherapy. Methods: From 1989 to 2000, a total of 100 patients underwent irradiation as part of their initial treatment for GBM. All patients had undergone surgery or biopsy followed by conventional external beam radiotherapy (RT). Eighty-five patients who received the planned curative dose of irradiation (60 Gy in 30 fractions) were analyzed for the influence of prognostic factors, 73/85 (86%) of patients were given postoperative RT, while 12/85 (14%) of patients were primarily treated with RT after biopsy, Results: The median overall survival was 10 months (range, 3-49), the 1and 2- year survival rates were 42% and 5%, respectively. Univariate analysis (log-rank test) revealed age up to 55 years (p<0.001), pre-RT hemoglobin (Hb) level over 12 g/alL (p=0.009), and pre-RT dose of dexamethasone up to 2 mg/day (p=O.006) to be associated with prolonged survival. At multivariate analysis (Cox's proportional hazards regression), younger age (p<0.001), higher Hb level (p=0.003), and a favourable tumor location (no evidence of corpus callosum, basal ganglia or brainstem involvement) (p=0.036) were identified as significant prognostic factors for overall survival. The median survival for patients with Hb level over 12 g/dL was 12 months compared to 7.5 months for those with lower Hb level. Contingencytable statistics (chi-square test) showed no significant differences for the two Hb groups in the distribution of age (p=0.178) and tumor location (p=l). We suggest that anemia may further increase the existing intratumoral hypoxia, thus making GBM even more resistant to RT. Conclusions: Our results indicate that Hb level prior to RT for GBM can influence prognosis. This finding deserves further evaluation,
Friday/Saturday, 20-21 September 2002 $297
1013
Poster
Development of treatment strategy of children with malignant intracranial tumors during the last decade of 20th c e n t u r y . A single center experience J. Marls, M. Chanova, B. Malinova, J. Koutecky UniversityHospital Motol, Pediatric Oncology, Prague, Czech Republic Objective: To RFS and OS for children with newly diagnosed malignant brain tumors where after surgery further conservative treatment was administered (radiotherapy and chemotherapy). Methods: During nineties of 20th century two protocols were used in majority of children with brain tumors: "8 in 1" and PNET/SIOP III protocol. The combination "8 in 1" was the treatment for 49 children (medutoblastoma 18, astrocytoma - 12, brain stem tumor - 10, ependymoma - 5, carcinoma 2, kraniopharyngeoma - 1, ependymoma - 1), med. age was 7,1 yrs. After surgery all children were irradiated up to 30 Gy on the whole craniospinar axis with boost of 20 Gy on the tumor area. After completion of radiotherapy all children received six courses of "Eight in One day chemotherapy" or till the time of tumor progression. Forty five children of this group was evaluated. In 1993 a PNET/SIOP III protocol was launched - 44 children were treated according this schedule. Median age was 9,0 yrs. Diagnoses inciuded medulloblastoma (42) and PNET (2). Complete removal of the tumor was performed in 21 pts, biopsy Or subtotal removal 24 pts. Chemotherapy was started after surgery and after then irradiation (30 Gy on craniospinat axis with boost of 20 Gy on the tumor). Forty two children was evaluated. All children treated with SlOP protocol were subdivided into three groups: I. - children where the tumor was completely resected (18) and there were no evidence of metastases, II. children with residual tumor (20) greater than 1 cm2, Ill. children with spread of disease within CNS (4). Results: In the "8 in 1" group 24 children (53 %) had recurrence of disease in reed. period of 7,1 mths and all relapsed children died. Only 21 pts. are followed in CR for approx. 8 yrs+ In the SlOP protocol group RFS at 1, 3 and 5 yrs were 79%, 52% and 43% respectively, OS at 1, 3 and 5 yrs were 81%, 60% and 45%. RFS for the children from the group I at 1, 3 and 5 yrs were 78%, 67% and 56%, OS at 1,3 and 5 yrs were 78%, 72% and 67%. Group II: RFS at 1, 3 and 5 yrs were 70%, 40% and 35%, OS at 1, 3 and 5 yrs were 70%, 50% and 40%. Group Ill: only one child is alive 3,5 yrs after the surgery. Conclusions: The crucial prognostic factor in children with malignant intracranial tumor is complete removal of the tumor and no evidence of leptomenigeal spread of disease. SlOP protocol improved the treatment results but longer follow up of this group is necessary. 1014
Poster
Stereotactic radiosurgery in essen - A database as tool for scientific workup of treatment results and quality control M. Attassi, M.K. Koemer, F. Guntrum, M.H. Seegenschmiedt Alfried-Krupp-Krankenhaus, Radioonkologie, Strahlentherapie und Nuklearmedizi,Essen, Germany Purpose: With growing acceptance of stereotactic radiotherapy among referring doctors and patients, more institutions are performing stereotactic radiosurgery (SRS) or fractionated stereotactic radiosurgery (SRT) in Germany. Guidelines of the RTOG define the dose homogeneity in stereotactic treatment planing volumes. However, no general accepted criteria exist regarding indication, recording of side effects, follow up and treatment outcome. We propose a common data pool open to collaborating clinics for better quality control and easier scientific work up especially in rare entities. Patients and methods: A stereotactic treatment database was designed to collect anonymised patient data, sex and age, diagnosis, planning parameters preceding and concomitant therapy and follow up including quality of life. Special attention was set to recording op potential side effects and treatment outcome. Representative MRI scans were digitally registered. Results: A new stereotactic treatment facility was build up in in early 2000 in the Alfried-Krupp-Krankenhaus, Essen, Germany. Beginning in 5/2000 up to 03/2002 a total of 108 patients (47 F; 61 M) were treated. Of these patients 63 (63%) had SRS and 36 (36%) had SRT. Median age was 59 (27-91) years. The diagnoses were mainly metastases and malignant brain tumors (74%) followed by benign diseases (26%), like menigeomas, arteriovenous-malformations and vestibular schwannomas. The ratio between the volume within prescribed isodoses and the target volumes were within the recommended range (RTOG-guidelines). Grade 3 and grade 4 acute and delayed side effects were seen in 4 cases (3,6% of SRS, 2,8 of SRT-treatments). Follow up is still short for most of the patients with ranges of I to 21 months. The presented data will be updated monthly. Conclusion: We present a new database as a tool for better quality control of stereotactic treatment according to RTOG guidelines. Regional clinics with SRS or SRT facilities are invited to contribute their own patients data.