CHEMOPREVENTION
TAKES AIM
AT D E V E L O P M E N T A N D RECURRENCE OF CRC
In the realm of medical oncology, today’s approach is to treat higher-stage cancers and/or those at high risk for recurrence with chemotherapy. Tomorrow’s approach may be to use drug therapy to prevent cancer from occurring in the first place, as well as recurrences of cancer. It’s called “chemoprevention,” and the Avera Cancer Institute has taken part in a number of clinical studies to determine the efficacy of possible preventive agents, including statins and NSAIDs. “The pathways for preventing cancer are many and varied, because each cancer has its own pathway of development,” said Dr. Addison Tolentino, board-certified Medical Oncologist. One open study is looking at the prevention of polyp formation and colon cancer through a combination of eflornithine and Sulindac. Sulindac is an NSAID, known to inhibit the COX-2 pathway. Eflornithine in cream form is actually used to retard the growth of facial hair. It inhibits an enzyme that is involved in polyamine synthesis. Excess polyamines have a role in the development of colorectal cancer. Eflornithine slows the body’s production of polyamines, while Sulindac helps cells eliminate excess polyamines.
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Similar to NSAIDs, statins may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth. A study that is now closed at Avera tested the drug rosuvastatin versus a placebo, in patients who had polyps and/or stage 0-3 colon cancer. An open trial is testing the use of celecoxib (Celebrex), an NSAID, in conjunction with FOLFOX, a standard chemotherapy regimen that is given 12 times over a period of six months. It is also testing the difference between giving FOLFOX six times over a period of three months, versus the regular 12-dose regimen. One of the drugs in FOLFOX, oxaliplatin, is known to cause neuropathy as a side effect. “Damage to nerve endings can be mild, or debilitating in some patients. The idea of this study is to see if we can decrease the amount of FOLFOX to half, and at the same time, see if Celebrex will in some way compensate for the three months not given,” Dr. Tolentino said.