Intraoperative high-dose rate interstitial irradiation of hepatic metastases from colorectal carcinoma. Results of a phase I-II trial.
BACKGROUND
Resection of liver metastases from colorectal carcinoma can be curative. Unresectable but liver-confined metastases might be ablated by high-dose radiation with a similar curative result.


METHODS
At Georgetown University Hospital, 22 patients with unresectable hepatic metastases from colorectal carcinoma underwent 24 interstitial irradiation procedures at laparotomy in a Phase I-II study. A single dose was administered with a high-dose rate iridium-192 afterloader. Dose to the tumor periphery was 20 Gy, 25 Gy, and 30 Gy in 13, 9, and 2 procedures, respectively.


RESULTS
No acute or chronic radiation toxicity has occurred at a median follow-up of 11 months. Median actuarial local control at irradiated sites was 8 months, with 26% actuarial local control at 26 months by computed tomography (CT) or magnetic resonance imaging (MRI) scanning. In the two patients undergoing two procedures each, a second biopsy of previously irradiated areas demonstrated tumor eradication.


CONCLUSIONS
This innovative, radical approach to unresectable colorectal hepatic metastases proved safe. Additional study is needed to determine whether interstitial irradiation is as effective as surgical resection, or whether it alters the natural history of the disease or longevity.
Thomas
D S
DS
Department of Radiation Medicine, Georgetown University School of Medicine, Washington, DC 20007.
Nauta
R J
RJ
Rodgers
J E
JE
Popescu
G F
GF
Nguyen
H
H
Lee
T C
TC
Petrucci
P E
PE
Harter
K W
KW
Holt
R W
RW
Dritschilo
A
A
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001918:Brachytherapy; D015179:Colorectal Neoplasms / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D003131:Combined Modality Therapy; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000532:radiotherapy* / Q000556:secondary* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D011879:Radiotherapy Dosage