FRIDAY, Jan. 20, 2012 (HealthDay News) -- Adding oxaliplatin to a standard chemotherapy regimen boosts survival rates for patients with advanced colon cancer, according to a new study that bolsters previous research on the drug by looking at a broader group of patients.
"Physicians and patients should be reassured from our findings that oxaliplatin is associated with marginally but consistently superior survival for patients diagnosed before age 75 years in community settings," the study authors said in a news release.
In past studies, oxaliplatin, as an adjuvant to the established treatment of 5-fluorouracil (5-FU), improved survival by up to 23 percent. But the new study looked at a different group of colon cancer patients, who were older, sicker, more racially diverse and had never participated in a controlled clinical study.
The study, led by Dr. Hanna Sanoff, an assistant professor of medicine, hematology and oncology at the University of Virginia School of Medicine, appears in the Jan. 20 issue of the Journal of the National Cancer Institute.
Colon cancer is one of the world's deadliest diseases, with more than 100,000 Americans diagnosed last year, the researchers noted. Of these, roughly a third had an advanced -- stage 3 -- cancer, for which surgery is the principal treatment.
Surgery alone produces disease-free survival rates of between 15 percent and 50 percent five years following treatment, according to study background information. To improve their chances, patients often also undergo post-surgical chemotherapy.
Up until 2004, the drug 5-FU -- given in combination with leucovorin, which boosts its effects -- was the chemotherapy of choice for colon cancer, sparking a 26 percent drop in death rates compared to patients undergoing surgery alone.
But in 2004, several U.S. National Cancer Institute studies indicated that by adding oxaliplatin to the 5-FU mix, patients could see survival rates rise by yet another 23 percent.
The one caveat: Only a tiny slice of cancer patients (less than 2 percent) participated in those clinical trials, and those tended to be younger, healthier and less diverse than the larger general population of colon cancer patients.
To determine whether oxaliplatin would show a similar benefit among a "real-world" population of patients, the authors sifted through five cancer registries containing survival information on more than 4,000 people with stage 3 colon cancer. All were younger than 75, and all had begun chemotherapy -- either a standard regimen or in combination with oxaliplatin -- within four months of having surgery between 2004 and 2009.
Researchers compared their survival rates with those of nearly 8,300 patients who had participated in one of five different clinical trials using oxaliplatin.
The addition of oxaliplatin to standard chemotherapy protocols was found to be just as effective in prolonging survival among the community-based set of patients -- including the elderly, minorities and those with additional complicating health issues -- who were not enrolled in studies.
For her part, Dr. Felice Schnoll-Sussman, a gastroenterologist at New York-Presbyterian Hospital/Weill Cornell Medical Center in New York City, said the finding "goes along with what we've previously known."
"So, it's not surprising," she said. "But, certainly this is positive. The analysis doesn't focus on some of the most common adverse reactions seen with this combination. But in terms of survival, it certainly supports our previously held belief that oxaliplatin increases survival and lowers the chance of cancer returning in some of those stage 3 post-surgery patients."
For more on colon cancer, visit the U.S. National Library of Medicine.