A paper presented at the recent 2011 Gastrointestinal Cancers Symposium conference reported important evidence that, for colorectal cancer patients getting chemotherapy after surgery, the sooner the better.
For people diagnosed with stage III colon cancer, stage II rectal cancer, or stage II colon cancer showing certain high-risk features, researchers found that each four-week delay in starting chemotherapy after surgery was associated with a 12% lower rate of survival five years later.
One important caveat: All of these studies were done when 5-FU was the only available treatment, before oxaliplatin was added to standard chemotherapy. It’s too early to know long-term results for today’s typical regimines.
Based on this review, though, the researchers concluded that it is indeed best to avoid unnecessary delay in starting chemotherapy, and that there may in fact still be benefits for giving chemotherapy even if it must be delayed several months after surgery.
The most likely causes for delay the researchers noted are complications and healing time needed after surgery, or “system delays” in appointments between surgeon, medical oncologist, and treatment sessions.
Dr. James J. Biagi and associates at Queen’s University in Kingston, Ontario were testing two clinical assumptions: First, that chemotherapy should begin as soon as possible after surgery — which they found to be true; and secondly, that chemotherapy offered beyond three months after surgery might not offer benefits — which they found to be not necessarily true.
Those assumptions “haven’t been, and won’t likely be tested in randomized trials,” Biagi noted, because that kind of trial would require intentionally delaying chemotherapy in eligible patients. Using mathematical meta-analysis, they compared outcomes for 14,000 patients in nine clinical studies reported between 1975 and 2009. They found that, among patients fit enough to start chemotherapy four weeks after surgery, treatments delayed until eight weeks showed a 12% higher five-year mortality, or 25% higher mortality when treatment started at 12 weeks.
Translating those statistics into a typical patient (using Adjuvent! Online—a tool that helps doctors and patients evaluate risks and benefits of adjuvant therapy), Dr. Biagi described how a 65-year-old man diagnosed with stage III colon cancer who started chemotherapy at four weeks would have a 60% survival chance of surviving five years; the same person would have a 55% survival rate starting treatment at eight weeks; or 50% survival rate starting treatment 12 weeks after surgery. (Again, these survival rates are from earlier 5-FU-only treatments.) This compared to an estimated 45% chance of five-year survival with no chemotherapy at all.
Patient take-away: Avoid unnecessary delay starting chemotherapy after surgery
- To help avoid complications from surgery that could delay healing, patients may want to seek colorectal surgery specialists.
- Patients can and should work to avoid delay between the surgeon’s referral to the medical oncologist who determines your chemotherapy treatment, and beginning scheduled treatments. If you’re considering delaying chemotherapy until after an important event (e.g. child’s wedding), talk with the oncologist and oncology nurse about how chemo might affect both your short-term lifestyle and long-term outcome.
- Also know that if delay is necessary (e.g. to heal from surgery complications), you still may benefit from chemotherapy, even as long as three months after surgery.
Source: J Clin Oncol 29: 2011 (suppl 4; abstr 364)
Previously: Delaying Chemotherapy After Surgery