New Strategies for Fighting Chemo Resistance

Ovarian cancer resistant to treatment may respond to chemo dose and timing changes

/ Author:  / Reviewed by: Robert Carlson, M.D

(RxWiki News) What if the odds of beating ovarian cancer could be improved by tinkering with existing chemotherapies? Tweaking chemo regimens may help patients who become resistant to initial therapies.

A recent study reviewed chemotherapy regimens for ovarian cancer that no longer responds to treatment.

Researchers found that shifting the doses and timing of existing chemotherapies may result in better success rates.

"Chemo questions?  Ask an oncologist."

David J. Pinato, PhD, postdoctoral Clinical Research Fellow in the Division of Experimental Medicine at Imperial College London in the UK, reviewed ovarian cancer treatment studies that experimented with the dosing and timing of chemotherapy regimens.

Typical advanced stage ovarian cancer treatments involve a surgery to remove the tumor followed by chemotherapy. The specific types of chemotherapy used in these advanced cases are combinations of carboplatin and paclitaxel every three weeks. Carboplatin is a platinum-based agent, and some ovarian cancer patients become resistant to it over time.

According to the study, ovarian cancer patients are considered resistant if the cancer returns within six months after surgery and three rounds of chemotherapy.

Patients who no longer respond to platinum chemotherapy are usually switched to other agents. Treatment is considered successful in a patient whose cancer does not worsen after 22 months and lives up to 57 months. However, the success rates for typical follow-up therapy are small—ranging between 5 to 15 percent.

For this study, authors reviewed attempts to use platinum-based chemotherapies with varying doses and timing in treatment-resistant patients.

The authors wrote, "In particular, platinum delivered weekly rather than 3 weekly (every 3 weeks), in a 'dose dense' fashion, with or without other drugs, may overcome proven clinical resistance to standard-schedule platinum, resulting in significant improvements in response."

Authors noted that such a strategy might be more expensive and inconvenient for patients.

This study will be published in an upcoming issue of Cancer Treatment Reviews.

No financial information was made publicly available.

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Review Date: 
February 2, 2013
Last Updated:
February 11, 2013