Phase II study on stereotactic body radiotherapy of colorectal metastases

Abstract

(2006) Phase II study on stereotactic body radiotherapy of colorectal metastases, Acta Oncologica, 45:7,[823][824][825][826][827][828][829][830]

Stereotactic Body Radiation Therapy for Patients with Heavily Pretreated Liver Metastases and Liver Tumors

“…While SBRT for liver metastases and primary tumors is a relatively new concept, a large body of retrospective literature is available describing early treatment results (Hoyer et al, 2006;Mendez Romero et al, 2006;Wulf et al, 2006;Lee et al, 2009;Rusthoven et al, 2009;van der Pool et al, 2010;Chang et al, 2011;Vautravers-Dewas et al, 2011) including four prospective Phase I studies (Schefter et al, 2005;Lee et al, 2009;Goodman et al, 2010;Rule et al, 2011). The earliest phase I trial reported by Schefter et al (2005) established the benefit and safety of SBRT for liver metastases with eligible patients having 1-3 lesions, tumor diameters <6 cm, and adequate liver function.…”

“…Stereotactic body radiation therapy (SBRT) is used to deliver ablative doses of radiation to an extracranial target with high precision and rapid fall-off that spares surrounding tissues. Early SBRT results revealed excellent tolerance and local control rates for liver metastases and primary liver tumors (Hoyer et al, 2006;Mendez Romero et al, 2006;Wulf et al, 2006;Lee et al, 2009;Rusthoven et al, 2009). The CyberKnife system (Accuray Inc., Sunnyvale, CA, USA) has several features that make it well suited for liver SBRT.…”

External radiation treatment of malignant liver disease: a critical review

“…Hoyer et al [83] described a phase II trial of SBRT for predominantly hepatic, unresectable CRC metastases and reported 2-year local or distant progression-free survival rates of 19% with overall survival of 38%. The prescribed dose was 45 Gy to the isocenter in three fractions.…”

Dose to organ at risk and dose prescription in liver SBRT

“…Hoyer et al 12 describes other prognostic factors related to improved local control including smaller tumor volumes, potentially non-CRC metastases, metachronous liver metastases and absence of previous chemotherapy. …”

“…10,11 Dose to the target is most often defined on the prescription isodose surrounding the PTV, which varies from 65 to 90%, and sometime on the isocenter. 7,12 Using intensity modulated radiation therapy (IMRT), the dose is prescribed to the mean dose in the PTV, and is less heterogeneous. 6 From a radiobiological point of view, the question of whether a classic radiobiological modeling, with the linearquadratic (LQ) model, is appropriate for large doses per fraction remains debated.…”