Why Clinical Cancer Research Trials are Important

 If measured by potential lives saved, the largest impact from clinical cancer research trials to date has been in cancer prevention, such as screening, early detection, and reduction of risk factors (i.e., smoking). 

The second largest impact from clinical cancer research trials has been adjuvant therapy. Adjuvant means “to go with” or after a primary therapy, such as hormone therapy following primary surgical resection of a breast tumor.   Research trials have shown adjuvant therapy (including chemotherapy and biological therapy) provides a significant impact on overall cure in most early stages of cancer.   

The area of clinical research that has yielded the least impact on cure rates is metastatic cancer.   In the last decade, clinical trials for metastatic treatments have generated more effective chemotherapies with fewer side effects and also led to an improvement in quality of life and lifespan, but has not led to a cure.  

But, there is reason to hope! The 21st century has ushered in exciting research in “targeted” cancer medicine. This new drug class has resulted in complete responses (shrinkage of tumor to undetectable size) for some rare tumor types.  The best example is Gleevec, a new cancer medicine used to treat Chronic Myeloid Leukemia (CML) and Gastrointestinal Stromal Tumors (GIST).  As Gleevec entered clinical trials, many patients immediately developed complete responses.  These brave patients with CML and GIST tumors who volunteered to participate in the orginal Gleevec clinical trials were among the first to benefit.  The excitement surrounding this new drug stems not only from its effectiveness, but also from the fact that scientists understood the exact genetic mechanism that causes these two cancers, and for the first time, developed a targeted therapy that inhibits this growth mechanism.  Finally, a complete understanding of a specific cancer growth mechanism at a genetic level has come full circle, leading to a targeted therapy.  Better yet, the therapy is in pill form, without chemotherapy side effects.   Gleevec is an excellent example of a targeted cancer therapy, but there are many more targeted drugs currently in development on trials.