Tardy Breast Cancer Surgery, Adjuvant Chemotherapy Reduces Survival

Prompt surgery and postoperative chemotherapy may aid breast cancer survival

medwireNews: Delaying breast cancer treatment reduces patient survival, confirm separate analyses of the impact of time to surgery (TTS) and time to chemotherapy (TTC) in US patients published in JAMA Oncology.

In the first, Richard Bleicher, from Fox Chase Cancer Center in Philadelphia, Pennsylvania, USA, and co-workers suggest that the interval between breast cancer diagnosis and surgery should be “minimized”, finding a significant and increasing deficit in survival for later treatment of noninflammatory, nonmetastatic, invasive breast cancer.

Compared with a TTS of less than 30 days, the hazard ratio (HR) for death was 1.09 for each additional 30-day interval for the 94,544 breast cancer patients aged 66 years and older who were entered into the Surveillance, Epidemiology, and End Results–Medicare database between 1992 and 2009.

And the HR for death was a comparable 1.10 for each 30-day delay to surgery for the 115,790 women diagnosed and registered in the National Cancer Database between 2003 and 2005, the authors say.

Subgroup analysis identified that the increased risk of poor survival was significant for women with stage I or II disease, with HRs of 1.16 and 1.09, respectively, although the risk did not reach significance for their stage III counterparts, after adjusting for demographic, tumour and treatment factors.

Eric Winer, from the Dana-Farber Cancer Institute in Boston, Massachusetts, USA, and co-authors of an accompanying opinion comment that this result “seemscounterintuitive if one assumes that patientswith higher-stage disease, who have a higher chance of micrometastases, may stand to benefit the most from timely treatment.”

They continue: “Conversely, as the authors imply, it is possible that a 30-day treatment delay carries less relative impact over the natural history of a more advanced tumor.”

The second study, examining outcomes of 24,843 patients with stage I–III breast cancer who were recorded in the California Cancer Registry between 2005 and 2010, demonstrated that a delay of 3 months or longer between surgery and receipt of adjuvant chemotherapy had a significant and adverse impact on patient survival.

The hazard ratios for poor overall survival and breast cancer-specific survival were 1.34 and 1.27, respectively, for patients who received adjuvant chemotherapy on day 91 or later compared with receipt within 31 days.

By contrast, there was no adverse impact for patients treated at 31–60 days or 61–90 days after surgery, reportMariana Chavez-MacGregor, from The University of Texas MD Anderson Cancer Center in Houston, USA, and co-authors.

Further analysis revealed that the brunt of delayed treatment was in women with triple-negative breast cancer, with a HR of 1.53 for both overall survival and breast cancer-specific survival.

Of concern, delay in TTC was associated with breast reconstruction and sociodemographic factors including low socioeconomic status, absence of private insurance and Hispanic and non-Hispanic Black race, prompting the authors to say that “removing barriers to access of care in vulnerable populations should be a priority.”

Mariana Chavez-MacGregor et alconclude: “Given the results of our analysis, we would suggest that all breast cancer patients that are candidates for adjuvant chemotherapy should receive this treatment within 91 days of surgery or 120 days from diagnosis.

“Administration of chemotherapy within this time frame is feasible in clinical practice under most clinical scenarios, and as medical oncologists, we should make every effort not to delay the initiation of adjuvant chemotherapy.”

References

Bleicher RJ, Ruth K, Sigurdson ER, et al. Time to surgery and breast cancer survival in the United States.JAMA Oncol 2015; Advance online publication 10 December.doi:10.1001/jamaoncol.2015.4508

Waks AG, King TA, Winer EP. Timeliness in breast cancer treatment – the sooner, the better.JAMA Oncol 2015; Advance online publication 10 December.doi:10.1001/jamaoncol.2015.4506.

Chavez-MacGregor M, Clarke CA, Lichtensztajn DY, Giordano SH. Delayed initiation of adjuvant chemotherapy among patients with breast cancer. JAMA Oncol 2015; Advance online publication 10 December.doi:10.1001/jamaoncol.2015.3856

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