The CyberKnife® Radiosurgery Solution
Hepatocellular Carcinoma
Definitive Therapy:
Unfortunately, a majority of patients with HCC will be unresectable for a variety of reasons ( 2). Though cure is unlikely in these patients, prolonged disease-free survival has also been reported with various radiotherapeutic approaches, with a demonstrated radiation dose response, translating to longer disease-free survival periods and occasional long-term survivors with larger radiation doses (15, 16, 17).
Hepatocellular carcinoma may be three dimensionally mapped with reasonable accuracy from radiology studies such CT or MRI, with one radiologic-pathologic correlative analysis revealing that contouring the radiographic lesion with 0.5 cm or 1.0 cm margins produced complete coverage of the histologic tumor extent in 93% and 100% of HCC patients, respectively (24).
This level of radiologic mapping accuracy allows the application of a precise radiation dose sculpting tool such as CyberKnife® to be accomplished in a manner that spares the maximum possible amount of normal hepatic parynchema and other adjacent sensitive tissues, enabling the application of a very high radiation dose that is potentially biologically ablative of the malignancy
In fact, the upper limit of partial liver tolerance to precisely conformal stereotactic radiotherapy has not yet been reached, in a large ongoing multi-institutional prospective dose escalation trial, which has already reached a biologic radiation dose equivalent to the targeted lesions greater than double that achievable with conventionally fractionated conformal radiotherapy (22, 23).
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