Bath Cancer Research
Short-term in vitro drug sensitivity tests for cancer chemotherapy. A summary of correlations of test result with both patient response and survival
Andrew G Bosanquet, Bath Cancer Research Unit, Wolfson Centre, Royal United Hospital, Bath, UK
Forum Trends in Experimental and Clinical Medicine 1994; Vol 4 (2): pp 179-195.
In vitro drug sensitivity tests have been investigated for over 40 years
as a method for identifying the sensitivity of individual patients to
anticancer chemotherapy. Two ways to assess the accuracy of these tests
are comparison of test result with clinical response (clinical correlations)
and comparison with patient survival. This review summarises 4,250 clinical
correlations including 510 from the differential staining cytotoxicity
assay (overall predictive accuracy (PA) = 83%), 489 from metabolic function
assays (PA = 81%) and 779 from the 3H-thymidine assays (PA = 74%). Where
assessed, patient survival was significantly longer in patients treated
with assay-sensitive compared with assay-resistant drugs. Initial publications
of results often show a higher PA compared with those reporting larger
numbers of clinical correlations. This has been termed the initial enthusiasm
factor, and is similar to the higher publication rate observed for "positive"
or "interesting" clinical trial results. Controlled clinical
trials comparing standard therapy with chemotherapy chosen by in vitro
assay result, including both an assessment of quality of life and an economic
evaluation, would encourage the use of these assays. This mass of data
is sufficient for initiating the widespread use of these assays; other
laboratory tests have been incorporated into routine clinical practice
with less confirmatory evidence than that presented here.