Progress In Colorectal Cancer
I remember the days when the only treatment for colorectal cancer was 5-fluorouracil and leucovorin, and it was not that long ago. On average, a patient with stage IV disease had between 1-2 years survival.
Then, the “new” chemotherapeutic agents started appearing. Irinotecan was FDA approved in 2000; oxaliplatin in 2004, xeloda was approved in 2004 as well. The beauty of xeloda is that it is an oral fluoropirimidine, which means that it can substitute continuous infusion 5fu making patient's lives a lot easier.
Oxaliplatin and xeloda are now part of adjuvant regimens for Duke C colon cancer, which confers a 38% improvement in survival.
What has been really exciting is the increasing knowledge of the biology of colorectal cancer and the discovery that certain receptors and growth factors are overexpressed contributing to the cancer growth that could now be used as the therapeutic targets. The overexpression of the EGFR (epidermal growth factor receptor) lead to the development of monoclonal antibodies that inhibit the receptor down regulating tumor cell growth. Erbitux was FDA approved in 2004 and vectibix in 2006 for metastatic colorectal cancer.
It is also well known that in order for tumors to grow and metastasize need an increased vascular supply and in order to do so they over express VEGF (vascular endothelial growth factor). VEGF has therefore become the target of new classes of agents called antiangiogenic therapies and avastin was FDA approved for stage IV colorectal cancer in 2004. Therefore, we are able to battle this disease with a variety of options including chemotherapy, monoclonal antibodies, and antiangiogenic treatments. This means that stage IV colorectal cancer patients live a lot longer than they used to and have the option of having therapeutic regimens that do not include chemotherapy agents avoiding nausea, vomiting and hair loss.
We still have a long way to go but we certainly have come a long way over the last 10 years.