Radiobiological intercomparison of the 160 MeV and 230 MeV proton therapy beams at the Harvard Cyclotron Laboratory and at Massachusetts General Hospital.

The purpose of this study was to determine the relative biological effectiveness (RBE) along the axis of two range-modulated proton beams (160 and 230 MeV). Both the depth and the dose dependence of RBE were investigated. Chinese hamster V79-WNRE cells, suspended in medium containing gelatin and cooled to 2 °C, were used to obtain complete survival curves at multiple positions throughout the entrance and 10 cm spread-out Bragg peak (SOBP).

Low-dose neoadjuvant external beam radiation therapy for soft tissue sarcoma.

Purpose: For soft tissue sarcoma, neoadjuvant external beam radiation therapy (EBRT) to 50 Gy has the same local control (LC) and overall survival as postoperative radiation therapy (PORT) to 60 Gy, but with increased wound complications. We examined whether low-dose neoadjuvant EBRT would decrease acute toxicity while maintaining LC.

Methods And Materials: From 1971 to 2008, 1,765 patients with nonmetastatic soft tissue sarcoma were treated with radiation therapy at Massachusetts General Hospital.

Phase II study of high-dose photon/proton radiotherapy in the management of spine sarcomas.

Purpose: Radiotherapy (XRT) for spine sarcomas is constrained by spinal cord, nerve, and viscera tolerance. Negative surgical margins are uncommon; hence, doses of >or=66 Gy are recommended. A Phase II clinical trial evaluated high-dose photon/proton XRT for spine sarcomas.

Inter- and intramouse heterogeneity of radiation response for a growing paired organ.

An intensive search for predictive markers of individual radiation response of apparently normal tissues in cancer patients is in progress at the genetic and epigenetic levels. However, the relative impact of variability at these levels is not clear. Experimental results obtained in inbred rodents, which have significantly reduced genetic heterogeneity relative to a population of human patients, may help to clarify this issue.

Radiation therapy for control of soft-tissue sarcomas resected with positive margins.

Purpose: Positive margins (PM) remain after surgery in some soft-tissue sarcoma (STS) patients. We investigated the efficacy of radiation therapy (RT) in STS patients with PM.

Methods And Materials: A retrospective chart review was performed on 154 patients with STS at various anatomic sites with PM, defined as tumor on ink, who underwent RT with curative intent between 1970 and 2001.

Treatment and outcome of 82 patients with angiosarcoma.

Background: Angiosarcomas are an uncommon type of malignancy that are generally thought to behave usually in a locally aggressive fashion; they often metastasize to distant sites.

Methods: Patients with a diagnosis of angiosarcoma treated at our institution between 1980 and 2006 were analyzed for patient demographics, tumor characteristics, multimodality treatment, and outcomes.

Results: A total of 82 patients were divided into those with primary and advanced disease.

Sacral chordomas: Impact of high-dose proton/photon-beam radiation therapy combined with or without surgery for primary versus recurrent tumor.

Purpose: To assess the efficacy of definitive treatment of sacral chordoma by high-dose proton/photon-beam radiation therapy alone or combined with surgery.

Methods And Materials: The records of 16 primary and 11 recurrent sacral chordoma patients treated from November 1982 to November 2002 by proton/photon radiation therapy alone (6 patients) or combined with surgery (21 patients) have been analyzed for local control, survival, and treatment-related morbidity. The outcome analysis is based on follow-up information as of 2005.

Results of radiation therapy for unresected soft-tissue sarcomas.

Purpose: Definitive radiotherapy is uncommonly used in the management of soft-tissue sarcoma (STS). The purpose of the study was to evaluate the results of radiotherapy for unresected STSs treated in a single institution.

Methods And Materials: Between 1970 and 2001, 112 patients with STSs underwent radiotherapy for gross disease.

Results of radiation therapy performed after unplanned surgery (without re-excision) for soft tissue sarcomas.

Background And Purpose: For soft tissue sarcomas (STS), some patients undergo an "unplanned surgery," non-oncologic resection for presumed benign tumor. The treatment of choice, in such cases, is re-excision combined (if indicated) with radiation. However, there are clinical situations when treatment by radiation alone is recommended.

Simulation of organ-specific patient effective dose due to secondary neutrons in proton radiation treatment.

Cancer patients undergoing radiation treatment are exposed to high doses to the target (tumour), intermediate doses to adjacent tissues and low doses from scattered radiation to all parts of the body. In the case of proton therapy, secondary neutrons generated in the accelerator head and inside the patient reach many areas in the patient body. Due to the improved efficacy of management of cancer patients, the number of long term survivors post-radiation treatment is increasing substantially.

Advanced-technology radiation therapy in the management of bone and soft tissue sarcomas.

Background: For patients with sarcomas, radiotherapy can be used as neoadjuvant, adjuvant, or primary local therapy, depending on the site and type of sarcoma, the surgical approach, and the efficacy of chemotherapy.

Methods: The authors review the current status of advanced technology radiation therapy in the management of bone and soft tissue sarcoma.

Results: Advances in radiotherapy have resulted in improved treatment for bone and soft tissue sarcomas.

Radiotherapy for local control of osteosarcoma.

Purpose: Local control of osteosarcoma in patients for whom a resection with satisfactory margins is not achieved can be difficult. This study evaluated the efficacy of radiotherapy (RT) in this setting.

Methods And Materials: We identified 41 patients in our sarcoma database with osteosarcomas that either were not resected or were excised with close or positive margins and who underwent RT with external beam photons and/or protons at our institution between 1980 and 2002.

Intraoperative dural irradiation by customized 192iridium and 90yttrium brachytherapy plaques.

Purpose: After vertebral or paravertebral tumor resection, tumor cells may remain on the dura. Because a tumoricidal dose is difficult to achieve using external beam radiotherapy without exceeding the spinal cord tolerance, we developed intraoperative applicators to deliver additional dose to the dura.

Methods And Materials: Eight patients with vertebral or paravertebral tumor underwent conformal external beam radiotherapy, tumor resection, and intraoperative radiotherapy to the dura involved by tumor.

Neoadjuvant chemotherapy and radiotherapy for large extremity soft-tissue sarcomas.

Purpose: Treatment of extremity soft-tissue sarcomas yields excellent local control, but distant failure is common with large, high-grade tumors. A regimen of preoperative chemotherapy consisting of mesna, adriamycin, ifosfamide, and dacarbazine (MAID) interdigitated with radiotherapy followed by resection and postoperative chemotherapy with or without radiotherapy was designed to improve treatment outcome. We report the mature outcome data on 48 treated patients and compare them with the data of an historical matched control patient population.

Responses to antiangiogenesis treatment of spontaneous autochthonous tumors and their isografts.

Preclinical studies typically use human tumor xenografts or murine tumor isografts. Tumor growth may be accelerated by in vivo passage, thus making these tumors more sensitive to some therapies than the original tumors. In the present study, by comparing the effects of DC101, an antimurine vascular endothelial growth factor receptor 2 (VEGFR2) monoclonal antibody, on spontaneous autochthonous tumors and their early generation transplants, we show that this growth acceleration is diminished by DC101 treatment.

Relative biological effectiveness (RBE) values for proton beam therapy.

Purpose: Clinical proton beam therapy has been based on the use of a generic relative biological effectiveness (RBE) of 1.0 or 1.1, since the available evidence has been interpreted as indicating that the magnitude of RBE variation with treatment parameters is small relative to our abilities to determine RBEs.