Breast cancer: Analyzing delays of chemotherapy after surgery
January 24, 2013 | by Shawn Le
With evidence from 20 years of clinical trials, the medical consensus is that chemotherapy treatment after surgery is beneficial for many breast cancer patients, reducing their risk of cancer recurrence. Now new research calls attention to potentially dangerous delays in such treatment.
Researchers from the National Comprehensive Cancer Network (NCCN), an alliance of 21 National Cancer Institute-designated comprehensive cancer centers, analyzed the timing for so-called adjuvant chemotherapy at member institutions, as well as factors that could be causing delays in such treatment.
Although the best timing for adjuvant chemotherapy has yet to be identified, lengthy delays in treatment are generally regarded as risky. The study found that 87 percent of women received chemotherapy within 120 days of diagnosis as recommended, but 6 percent didn’t start chemotherapy until after that recommended window of time. The results of the review study were published online Dec. 21 in the Journal of the National Cancer Institute. The study reviewed information in the NCCN Outcomes Database for 6,222 women treated for stage I through stage III hormone receptor-negative breast cancers diagnosed from 2003 through 2009. All of the women received chemotherapy after surgery at one of nine member institutions.
Researchers used a treatment guideline from the NCCN and the American Society of Clinical Oncology as a baseline measurement to evaluate the care provided to the breast cancer patients. The guideline recommends that women under 70 years old and diagnosed with stage II or stage III hormone receptor-negative breast cancer receive adjuvant chemotherapy within 120 days of their diagnosis.
Several factors were linked to treatment delays; among them were race and insurance coverage. Overall, the average time from diagnosis to surgery was 5.6 weeks, and the average time between surgery and adjuvant chemotherapy was 6.3 weeks. Compared to white women, black women waited an additional 1.5 weeks on average between surgery and chemotherapy. And black women treated through Medicare experienced longer delays than black women with private insurance.
But not all delays were tied to negative factors. Some treatment delays were due to extra diagnostic testing and therapeutic interventions. Patients who underwent a specific genetic test to predict their response to chemotherapy were delayed an additional 2.2 weeks on average, allowing their treatment to be better tailored to their cancer. Breast reconstruction immediately after a mastectomy added an average delay of 2.7 weeks.
Researchers said their review highlighted issues that need further study – such as understanding the root causes of the racial disparity in timely treatment. The authors wrote: “Future studies of patients diagnosed earlier with longer follow-up are needed to better assess the association of delay with breast cancer outcomes.”
Joyce C. Niland, Ph.D., chair of City of Hope’s Department of Research Information Sciences and the Edward and Estelle Alexander Chair in Information Sciences, was among the researchers taking part in the study.
Other than City of Hope, the NCCN cancer centers participating in the study were: Dana-Farber/Brigham Women’s Cancer Center in Boston; Fox Chase Cancer Center in Philadelphia; the University of Texas M.D. Anderson Cancer Center in Houston; Lee Moffitt Cancer Center and Research Institute in Tampa, Fla.; Arthur G. James Cancer Hospital and Richard J. Solove Research Institute at the Ohio State University in Columbus, Ohio; Roswell Park Cancer Institute in Buffalo, N.Y.; University of Michigan Comprehensive Cancer Center in Ann Arbor, Mich.; and UNMC Eppley Cancer Center at the Nebraska Medical Center in Omaha, Neb.
In an accompanying editorial, researchers wrote: “Initiatives to improve transfers in care and optimize definition of surgical margins, as well as thoughtful use of imaging, are within our control and should be pursued. However, some of these 'delays' … have greatly improved patient care. This suggests that we should proceed with caution before using time to initiation of treatment as a quality measure for breast cancer treatment. Evaluating time to treatment outside of the context of outcomes cannot accurately access quality. Indeed, faster is not always better.”
The study was supported with a grant from the National Cancer Institute (P50 CA89393 to Dana-Farber Cancer Institute).