In:
Journal of Clinical Oncology, American Society of Clinical Oncology (ASCO), Vol. 30, No. 4_suppl ( 2012-02-01), p. 257-257
Abstract:
257 Background: This multi-institutional phase I trial was conducted to determine the maximally tolerated dose (MTD) of hypofractionated, highly conformal radiation therapy (RT) in patients (pts) with liver metastases. Methods: Eligibility criteria included non-surgical pts with ≤ 5 liver metastases; total measurement for all lesions ≤ 8 cm. There were four dose levels (DLs) escalating from 35 Gy to 50 Gy in 5 Gy increments given in 10 fractions with defined normal tissue dose limits. Accrual began at 40 Gy. The clinical target volume (CTV) included all metastases identified on contrast CT/MRI with a 5 mm margin. The planning target margin ranged from 4 to 30 mm around the CTV. For quality assurance the Image-Guided Therapy Center (ITC) remote review tool was used to evaluate treatment planning images and dosimetry information. Dose limiting toxicities (DLTs) were defined as treatment-related grade (Gr) ≥ 4 hepatic, gastrointestinal (GI), thrombocytopenia, or radiation induced liver disease (RILD) within 90 days (dys) of the start of RT. Results: 26 pts were enrolled between 11/05 and 12/10, and 23 were evaluable; 8, 7, and 8 on the 40, 45, and 50 Gy DLs respectively. Two pts assigned to the 50 Gy DL received 35 Gy because of normal tissue constraints, therefore an additional 2 pts were accrued and treated at the 50 Gy DL. The study was temporarily closed for toxicity evaluation after 6 pts on each DL were followed for a minimum of 90 dys from start of treatment. There were no DLTs observed on any of the DLs. Four pts developed treatment-related Gr 3 toxicities; 2 each on the 45 and 50 Gy DLs. On the 45 Gy DL, 1 pt had two Gr 3 GI toxicities: enteritis (37 dys from RT start) and diarrhea (22 dys) while another pt had Gr 3 lymphopenia (23 dys). On the 50 Gy DL, 1 pt had Gr 3 hyperglycemia (74 dys) and another pt had three Gr 3 toxicities: lymphopenia (13 dys), colonic hemorrhage (325 dys), and GI obstruction (325 dys). Conclusions: When normal tissue constraints could be met, treatment of liver metastases with 50 Gy in 5 Gy/fx is feasible and safe in a multi-institutional setting. Further studies looking at higher doses and alternate fractionation regimens are warranted. Supported by RTOG U10 CA21661, CCOP U10 CA37422 and ATC U24 CA 81647 NCI grants.
Type of Medium:
Online Resource
ISSN:
0732-183X
,
1527-7755
DOI:
10.1200/jco.2012.30.4_suppl.257
Language:
English
Publisher:
American Society of Clinical Oncology (ASCO)
Publication Date:
2012
detail.hit.zdb_id:
2005181-5
detail.hit.zdb_id:
604914-X
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