Caveats About Screening
Despite the advisability of screening, and the improved methods now available for screening, patients, their families and friends, and their physicians must keep in mind the fact that screening is not 100% accurate or fool-proof. Combinations of methods improve sensitivity and specificity and the predictive values of positive or negative results, but even these combinations are also not fool-proof.
Screening for HCC: Caveats
- No single method is fool-proof
- Combinations of methods improve sensitivity, specificity, and predictive values of positive or negative results BUT
- No combination is foolproof
- Evidence for improved survival or improved quality-adjusted life as result of screening is lacking: No prospective, randomized, controlled trials; No good cost-benefit analyses
- Screening of high-risk groups now the routine standard of care in the USA, Japan, Taiwan, Europe, Australia, New Zealand, and other developed regions
In addition, there is no solid evidence to show that overall survival or good quality survival is improved as a result of screening for HCC. There are retrospective data, chiefly from Japan, showing that HCC is being detected at an earlier stage than was the case prior to performance of routine screening.
Aggressive therapy of these early small cancers leads to improved patient outcomes, when results are compared with historic control patients. However, the strongest evidence of benefit for screening would come from prospective, randomized, controlled trials, in which one group of patients would undergo screening, while another group of control patients would have only routine follow-up.
A few such trials were done in the 80s and 90s, mainly in southern Europe, and the findings from these trials failed to show overall improved survival benefit. There also has not been convincing demonstration of the economic efficiency of routine screening for HCC, as might be shown by formal cost-benefit analyses and calculations of costs for diagnosis of one additional case of HCC or the cost for one additional year of good-quality life in patients at risk for HCC.
Skeptics may therefore still insist, with some basis in fact, that routine screening studies for HCC are not mandated, based upon the currently available evidence. Despite this lack of evidence, however, screening of high risk groups is now the routine care in the USA, Japan, Taiwan, Western Europe, Australia, New Zealand, and other developed countries and regions of the world. In the new millennium, it will be difficult if not totally impossible to perform prospective, randomized, multi-center, controlled trials on screening for HCC in the USA and similar countries.
