It doesn’t hurt to stop XELOX chemotherapy combined with Avastin after six treatments and continue with Avastin alone until colorectal cancer gets worse, according to a study reported at the 2010 Annual Meeting of the American Society of Clinical Oncology in Chicago.
Many patients have to stop oxaliplatin chemotherapy with before getting its maximum effectiveness because of peripheral neuropathy — tingling, numbness, or pain in their hands and feet. Xeloda® (capecitabine) can cause painful skin redness and cracking on the hands and feet or hand-foot syndrome, which can also affect time on chemotherapy.
Giving only six treatments of Avastin® (bevacizumab) plus XELOX chemotherapy and then stopping XELOX and using only Avastin until cancer progressed was as effective for the initial or first-line treatment of colorectal cancer as continuing XELOX. XELOX combines Xeloda® (capecitabine) with oxaliplatin.
In addition, the strategy reduced both severe peripheral neuropathy and hand-foot syndrome.
In the MACRO study, 480 patients who had not received previous chemotherapy for metastatic colorectal cancer were randomly assigned to get either get
- XELOX and Avastin until their cancer progressed or side effects made it impossible for them to continue treatment or
- Six treatments (18 weeks) of XELOX and Avastin followed by Avastin alone until progression.
After a median follow-up of 16 months, there were no significant differences in response rate, progression-free survival, or overall survival time.
- Median progression-free survival was 11.0 months when XELOX continued and 10.3 months when XELOX was dropped and Avastin continued as a single agent.
- Median overall survival was 25.3 months with continuous XELOX and 20.7 months continuing Avastin alone.
- Overall response rate was 60 percent for the continuing strategy and 57 percent for Avastin as a single agent after XELOX was stopped.
Severe grade three or worse side effects were
- Diarrhea: 11 percent in continuing strategy and 13 percent when Avastin was used alone.
- Hand-foot syndrome: 12 percent versus 6 percent.
- Neuropathy: 24 percent versus 7 percent
The researchers also pointed out that about 1 in 10 patients in both arms of the trial were able to have successful surgery to remove metastatic tumors.
Josef Tabernero, MD, and his colleagues concluded,
Bevacizumab (BEV) as a maintenance therapy following induction XELOX-BEV was not inferior to continuation XELOX-BEV. This study suggests that maintenance therapy with single agent bevacizumab is an appropriate option following induction XELOX-BEV in patients with metastatic colorectal cancer. Further studies evaluating single agent bevacizumab after standard chemotherapy in metastatic colorectal cancer are warranted.
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