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316 poster CT images versus simulator images for dose planning of head & neck tumours
Posters
316 poster CT images versus simulator images for dose planning of head & neck tumours
M. Lundell, J. Nilsson, S. Persson Radiumhemmet, Karolinska Hospital, Dept of Hospital Physics, Stockholm, Sweden At Radiumhemmet, head-neck tumours have been treated with brachytherapy since 2001. Most patients get a boost treatment with brachytherapy after a course of external radiotherapy. Until some months ago we have based our dose planning only on simulator images. The dose planning system used was the Plato, version 14.2, from Nucletron. When using simulator images it is easy to define the target volume, and quickly done, as this is only given in two dimensions. The goal, however, must be to make a dose plan as homogenous as possible and that the 100 % isodose encloses all the catheters without getting too large hot spots. This is especially difficult if the catheters are not parallel. Some months ago we started to use CT images for dose planning. We still use the Plato system but it is now upgraded with the modules "Insight" and "Inverse optimization". Now, when using CT slices, the physician has to outline the target volume in each slice regardless of the position of the catheters. Although this method is more time consuming for both the physicians and the physicists, the dose planning issue is to get a more homogenous dose distribution within the target volume, than was possible with the old technique. We now report the preliminary results of a study that has been performed to compare the full dose volumes by the two methods. In all cases, the best results are obtained by using the CT-based technique. Differences between the two methods and the difficulties encountered when using CT images for dose planning of head neck tumours will be discussed. 317 poster The role of high dose rate (HDR) brachytherapy in the management of soft tissue sarcomas
J. Maier ~, R. Patel 1, J. Fugazzi~, D. Perry 1, M. Mott2, E. Ben ~ M . Yudelev ~, C. Zuniga ~, A. Frazier 1 I Wayne State University, Radiation Oncology, Detroit, U.S.A. 2Wayne State University, Orthopedics, Detroit, USA 3University of Michigan, Radiation Oncology, Ann Arbor, USA Purpose: This study evaluates the local control and toxicity for patients undergoing HDR brachytherapy with or without external beam radiation therapy following resection of soft tissue sarcomas. Materials and Methods: Between September 1, 1996 and August 30, 2003, 30 patients were treated curatively for STS with resection and adjuvant HDR brachytherapy alone or followed by photon irradiation. Catheters were placed at time of resection. A median of 5 catheters were placed (range 2-18) and HDR treatments were started within 3-10 days of surgery (median 5 days). Twenty of the patients were treated for primary sarcomas and 10 were treated for recurrent disease. No patients had evidence of metastatic disease. The median age of the treated patients was 55 years old (range 2379). The pathologic subtypes were as follows: malignant fibrous histiocytomas: 15 patients, liposarcomas: 4 patients, leiomyosarcomas: 3 patients, and other: 8 patients. Patients receiving HDR brachytherapy alone (7 pts) received a median dose of 38 Gy (28.25-42 Gy) with a median of 8 fractions (512). Median dose per HDR fraction was 3.3 Gy (2.45-3.5 Gy). Those patients receiving HDR prior to XRT received a median dose of 20 Gy (13.6-24 Gy) followed by a median photon dose of 42 Gy (20.4-50.4 Gy) in 1.8 to 2.0 Gy fractions.
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Results: With a median follow-up of 34 months (3-87 months), three patients had evidence of local recurrence. One of these patients died with systemic disease. The 5-year actuarial rate of local control was 88%. The treatment was well tolerated. The most common side effect was skin erythema during the external beam radiation. One patient had moist desquamation which required a treatment break during photon irradiation and two patients developed infection. One of these patients was treated with HDR alone for recurrent sarcoma and developed cellulitis 7 months after treatment, requiring surgical debridement. The second patient developed a wound infection shortly after removal of the HDR catheters and required intravenous antibiotics. Conclusions: HDR brachytherapy alone or in combination with external beam radiation provides excellent local control and is well tolerated in patients with primary or recurrent STS. These results appear similar to previous studies for low dose rate brachytherapy for STS. 318 poster HDR and LDR brachytherapy in the treatment of paediatric tumours. A single institution experience on 21 patients
R. Mazzarotto, M.S. Buzzaccarini, G. Scarzello, A. Rigon, F. Vianello, G. Cecchetto, M. Carli, U. Cillo, G. Sotti Azienda Ospedaliera di Padova, Radiotherapy, Padova, Italy Surgery, chemotherapy and EBRT are commonly used in the treatment of most cancers in paediatric patients (pts). However, the severe late effects, particularly growth retardation and deformities, associated with EBRT when performed in growing patients, represent a serious concern and often limit its use. If EBRT is excluded from treatment protocols, or used on limited fields and with low doses, the probability of recurrence increases. Brachytherapy, allowing to deliver high radiation doses to limited volume while sparing surrounding tissues, improves the therapeutic ratio thus being particularly important in growing patients. LDR-BT showed to be effective but not practical particularly in very young patients and was gradually abandoned. Fractionated HDR-BT needs very short treatment time and seems to be the best treatment technique particularly in very young pts. From 1991 to 2003, 21 paediatric patients were treated with BT as part of the treatment programme. Nineteen patients with soft tissue sarcomas (STS), were enrolled in the Italian Cooperative RMS-88 and RMS-96 Studies, while 1 pt with hepatoblastoma and 1 with hepatocarcinoma, both in transplanted liver, underwent treatment protocols in use for these tumours in our hospital. There where 8 males and 13 females. Median age was 10 yrs (rain 2, max 20). Histology was: RMS in 11 (A in 4 and E in 7), PNET in 2, synovialsarcoma in 1, leiomyosarcoma in 1, liposarcoma in 1, schwannoma in 2, hepatoblastoma in 2, desmoid fibromatosis in 1 pt. Sites of disease were as follows: head and neck in 5 pts, trunk in 2, limbs in 6, vagina in 6 and liver in 2. The IRS stage for 19 pts with STS was: I in 2, II in 9, III in 2, while 6 pts were treated at first relapse: after surgery in 1, after surgery and chemotherapy in 3 and after surgery plus chemotherapy and EBRT in 2. The 2 pts with liver disease were treated with HDR-BT at relapse after surgery and chemotherapy. Interstitial BT was performed in 11 pts, endocavitary BT in 8 (1 nasal fossa and 7 vagina). The 2 pts with liver cancer were treated with perioperative contact HDRBT; the catheters were fixed to the surface of the resected liver with the aim of Vicryl net, passed through the abdomen wall and fixed to the skin. HDR-BT was performed postoperatively, with a dose of 42 Gy in 14 fractions b.i.d. 6 hours apart. LDRBT was performed in the first 8 pts, HDR-BT in the last 13 pts. In LDR-BT treatments, the dose varied from 20 Gy (boost dose)
316 poster CT images versus simulator images for dose planning of head & neck tumours
M. Lundell, J. Nilsson, S. Persson Radiumhemmet, Karolinska Hospital, Dept of Hospital Physics, Stockholm, Sweden At Radiumhemmet, head-neck tumours have been treated with brachytherapy since 2001. Most patients get a boost treatment with brachytherapy after a course of external radiotherapy. Until some months ago we have based our dose planning only on simulator images. The dose planning system used was the Plato, version 14.2, from Nucletron. When using simulator images it is easy to define the target volume, and quickly done, as this is only given in two dimensions. The goal, however, must be to make a dose plan as homogenous as possible and that the 100 % isodose encloses all the catheters without getting too large hot spots. This is especially difficult if the catheters are not parallel. Some months ago we started to use CT images for dose planning. We still use the Plato system but it is now upgraded with the modules "Insight" and "Inverse optimization". Now, when using CT slices, the physician has to outline the target volume in each slice regardless of the position of the catheters. Although this method is more time consuming for both the physicians and the physicists, the dose planning issue is to get a more homogenous dose distribution within the target volume, than was possible with the old technique. We now report the preliminary results of a study that has been performed to compare the full dose volumes by the two methods. In all cases, the best results are obtained by using the CT-based technique. Differences between the two methods and the difficulties encountered when using CT images for dose planning of head neck tumours will be discussed. 317 poster The role of high dose rate (HDR) brachytherapy in the management of soft tissue sarcomas
J. Maier ~, R. Patel 1, J. Fugazzi~, D. Perry 1, M. Mott2, E. Ben ~ M . Yudelev ~, C. Zuniga ~, A. Frazier 1 I Wayne State University, Radiation Oncology, Detroit, U.S.A. 2Wayne State University, Orthopedics, Detroit, USA 3University of Michigan, Radiation Oncology, Ann Arbor, USA Purpose: This study evaluates the local control and toxicity for patients undergoing HDR brachytherapy with or without external beam radiation therapy following resection of soft tissue sarcomas. Materials and Methods: Between September 1, 1996 and August 30, 2003, 30 patients were treated curatively for STS with resection and adjuvant HDR brachytherapy alone or followed by photon irradiation. Catheters were placed at time of resection. A median of 5 catheters were placed (range 2-18) and HDR treatments were started within 3-10 days of surgery (median 5 days). Twenty of the patients were treated for primary sarcomas and 10 were treated for recurrent disease. No patients had evidence of metastatic disease. The median age of the treated patients was 55 years old (range 2379). The pathologic subtypes were as follows: malignant fibrous histiocytomas: 15 patients, liposarcomas: 4 patients, leiomyosarcomas: 3 patients, and other: 8 patients. Patients receiving HDR brachytherapy alone (7 pts) received a median dose of 38 Gy (28.25-42 Gy) with a median of 8 fractions (512). Median dose per HDR fraction was 3.3 Gy (2.45-3.5 Gy). Those patients receiving HDR prior to XRT received a median dose of 20 Gy (13.6-24 Gy) followed by a median photon dose of 42 Gy (20.4-50.4 Gy) in 1.8 to 2.0 Gy fractions.
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Results: With a median follow-up of 34 months (3-87 months), three patients had evidence of local recurrence. One of these patients died with systemic disease. The 5-year actuarial rate of local control was 88%. The treatment was well tolerated. The most common side effect was skin erythema during the external beam radiation. One patient had moist desquamation which required a treatment break during photon irradiation and two patients developed infection. One of these patients was treated with HDR alone for recurrent sarcoma and developed cellulitis 7 months after treatment, requiring surgical debridement. The second patient developed a wound infection shortly after removal of the HDR catheters and required intravenous antibiotics. Conclusions: HDR brachytherapy alone or in combination with external beam radiation provides excellent local control and is well tolerated in patients with primary or recurrent STS. These results appear similar to previous studies for low dose rate brachytherapy for STS. 318 poster HDR and LDR brachytherapy in the treatment of paediatric tumours. A single institution experience on 21 patients
R. Mazzarotto, M.S. Buzzaccarini, G. Scarzello, A. Rigon, F. Vianello, G. Cecchetto, M. Carli, U. Cillo, G. Sotti Azienda Ospedaliera di Padova, Radiotherapy, Padova, Italy Surgery, chemotherapy and EBRT are commonly used in the treatment of most cancers in paediatric patients (pts). However, the severe late effects, particularly growth retardation and deformities, associated with EBRT when performed in growing patients, represent a serious concern and often limit its use. If EBRT is excluded from treatment protocols, or used on limited fields and with low doses, the probability of recurrence increases. Brachytherapy, allowing to deliver high radiation doses to limited volume while sparing surrounding tissues, improves the therapeutic ratio thus being particularly important in growing patients. LDR-BT showed to be effective but not practical particularly in very young patients and was gradually abandoned. Fractionated HDR-BT needs very short treatment time and seems to be the best treatment technique particularly in very young pts. From 1991 to 2003, 21 paediatric patients were treated with BT as part of the treatment programme. Nineteen patients with soft tissue sarcomas (STS), were enrolled in the Italian Cooperative RMS-88 and RMS-96 Studies, while 1 pt with hepatoblastoma and 1 with hepatocarcinoma, both in transplanted liver, underwent treatment protocols in use for these tumours in our hospital. There where 8 males and 13 females. Median age was 10 yrs (rain 2, max 20). Histology was: RMS in 11 (A in 4 and E in 7), PNET in 2, synovialsarcoma in 1, leiomyosarcoma in 1, liposarcoma in 1, schwannoma in 2, hepatoblastoma in 2, desmoid fibromatosis in 1 pt. Sites of disease were as follows: head and neck in 5 pts, trunk in 2, limbs in 6, vagina in 6 and liver in 2. The IRS stage for 19 pts with STS was: I in 2, II in 9, III in 2, while 6 pts were treated at first relapse: after surgery in 1, after surgery and chemotherapy in 3 and after surgery plus chemotherapy and EBRT in 2. The 2 pts with liver disease were treated with HDR-BT at relapse after surgery and chemotherapy. Interstitial BT was performed in 11 pts, endocavitary BT in 8 (1 nasal fossa and 7 vagina). The 2 pts with liver cancer were treated with perioperative contact HDRBT; the catheters were fixed to the surface of the resected liver with the aim of Vicryl net, passed through the abdomen wall and fixed to the skin. HDR-BT was performed postoperatively, with a dose of 42 Gy in 14 fractions b.i.d. 6 hours apart. LDRBT was performed in the first 8 pts, HDR-BT in the last 13 pts. In LDR-BT treatments, the dose varied from 20 Gy (boost dose)