title: Interim analysis of a prospective phase I/II trial of SBRT for liver metastases.
abstract: Stereotactic Body Radiation Therapy (SBRT) is a potent means of systemic cytoreductive therapy for selected patients with metastatic cancer. We here report an interim analysis of a prospective Phase I/II study of SBRT for liver metastases. Eligible patients with liver metastases met these criteria: (1) maximum tumor diameter < 6 cm; (2) < or =3 discrete lesions; (3) treatment planning confirmed > or = 700 cm3 of normal liver receives < or =15 Gy. The gross tumor volume (GTV) was expanded 5-10 mm to yield the planning target volume, which received 60 Gy in 3 fractions of SBRT over 3-14 days in the Phase II component of the trial. As of July, 2006, 36 patients have been enrolled: 18 in Phase I, 18 in Phase II. The median age was 58 years (range 27-91); the M:F ratio was 20:16. The most common primary sites were lung (n = 10), colorectal (n = 9), and breast (n = 4). Among 21 pts with > or = 6 months post-SBRT follow-up (median 19 months, range 6-29), one instance of SBRT-related grade 3 toxicity occurred in subcutaneous tissue superficial to the liver. No grade IV toxicity occurred. For 28 discrete lesions treated (median GTV 14 cm3, range 1-98) the 18 month actuarial local control estimate is 93%. This interim analysis indicates that a very high rate of durable in-field tumor control can be safely achieved with SBRT to 1-3 liver lesions as administered in this protocol, to a prescription dose of 60 Gy in 3 fractions.
authors.affiliation: Department of Radiation Oncology, University of Colorado, Aurora, Colorado 80045, USA. Brian.Kavanagh@uchsc.edu
authors.forename: Brian D
authors.initials: BD
authors.lastname: Kavanagh
authors.forename: Tracey E
authors.initials: TE
authors.lastname: Schefter
authors.forename: Higinia R
authors.initials: HR
authors.lastname: Cardenes
authors.forename: Volker W
authors.initials: VW
authors.lastname: Stieber
authors.forename: David
authors.initials: D
authors.lastname: Raben
authors.forename: Robert D
authors.initials: RD
authors.lastname: Timmerman
authors.forename: Martin D
authors.initials: MD
authors.lastname: McCarter
authors.forename: Stuart
authors.initials: S
authors.lastname: Burri
authors.forename: Lucien A
authors.initials: LA
authors.lastname: Nedzi
authors.forename: Timothy E
authors.initials: TE
authors.lastname: Sawyer
authors.forename: Laurie E
authors.initials: LE
authors.lastname: Gaspar
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002277:Carcinoma / Q000000981:diagnostic imaging / Q000556:secondary* / Q000601:surgery* / Q000628:therapy; D003131:Combined Modality Therapy / Q000009:adverse effects; D064420:Drug-Related Side Effects and Adverse Reactions; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000000981:diagnostic imaging / Q000556:secondary* / Q000601:surgery* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D011859:Radiography; D016634:Radiosurgery / Q000009:adverse effects / Q000379:methods*; D011878:Radiotherapy / Q000009:adverse effects; D011879:Radiotherapy Dosage; D016879:Salvage Therapy; D051598:Whole Body Imaging