Older Age Should Not Rule Out Chemo in Breast Cancer Patients

In Clinical Studies News by Barbara Jacoby

By: Leah Lawrence, Contributing Writer

From: medpagetoday.com

Elderly women benefitted from undergoing adjuvant chemotherapy for their node-positive, estrogen receptor-positive breast cancer, even in the presence of multiple comorbidities, retrospective data suggested.

A large study of 1,592 patients in the U.S. National Cancer Database from 2010 to 2014 showed that after adjustment for other risk factors, women ages 70 and older who underwent chemotherapy (n=350) for breast cancer had a 33% reduced risk for death compared with those who had no chemotherapy (HR 0.67, 95% CI 0.48-0.93, P=0.02), according to Nina Tamirisa, MD, of the University of Texas MD Anderson Cancer Center, and colleagues.

Other factors associated with improved survival were receipt of endocrine therapy (HR 0.47, 95% CI 0.31-0.72, P<0.001) and radiation therapy (HR 0.61, 95% CI 0.43-0.87, P=0.006), they reported in JAMA Oncology.

In contrast, women with a Charlson/Deyo comorbidity score of 3 compared with 2 had significantly worse survival (HR 1.94, 95% CI 1.34-2.79, P<0.001), as did those with a higher pathologic T stage (pT4 vs pT1, HR 3.51, 95% CI 1.86-6.62, P<0.001) and those with a higher pathologic N stage (pN3 vs pN1, HR 1.71, 95% CI 1.09-2.69, P=0.04).

“When evaluating these patients in a retrospective fashion, there are certainly unmeasured variables with respect to differences in luminal subtype and patient characteristics that contribute to our findings of improved survival in those patients treated with chemotherapy,” Tamirisa told MedPage Today. “In light of the increasing aging population and increased risk of breast cancer with age, our study underscores the importance of including older patients with comorbidities in clinical trials.”

In an editorial that accompanied the study, Nicolò Matteo Luca Battisti, MD, of the Royal Marsden National Health Service Foundation Trust, and colleagues pointed out the importance of using a large, nationwide database that includes information on real-world outcomes; however, among the “unmeasured variables” missing from the U.S. National Cancer Database are comprehensive geriatric assessments — which are now recommended by the American Society of Clinical Oncology for older patients with cancer receiving chemotherapy — and information on quality of life.

“Global health is a continuum that involves different domains, which is particularly relevant for older patients with cancer,” Battisti and colleagues wrote. “In older adults, several factors may be associated with survival outcomes, but survival should not be regarded as the only relevant end point of therapeutic approaches or considered in the absence of other important considerations, such as quality of life.”

Indeed, Tamirisa said that several factors outside of a patient’s age should be considered when weighing treatment options, such as comorbidities, functional status, the impact on quality of life with respect to toxicity, and estimated life expectancy.

“The goal is to avoid compromising a patient’s functional status, especially in the context of an already limited life expectancy,” Tamirisa said. “It is imperative for providers to understand patient priorities with respect to maintaining independence in activities of daily living that could be impacted by toxicities from treatment.”

Tamirisa and colleagues also acknowledged that despite their efforts, they could not eliminate all selection bias. Women who received chemotherapy were younger (74 vs 78 years; P<0.001), had larger primary tumors (P=0.005), and had higher pathologic nodal burden (P<0.001). This suggests that physicians “carefully selected patients likely to derive treatment benefit from adjuvant chemotherapy despite multiple comorbidities based on certain unmeasured variables.”

Identifying the older women who will benefit from treatment, Battisti and colleagues noted, continues to be the challenge.

“Chronologic age alone does not fully capture the complexity of elderly patients with cancer,” they wrote. “In this group of patients, treatment considerations should be individualized based not only on prognostic tumor-related factors but also on the global health status of patients, which is crucial to determine life expectancy and treatment tolerance.”

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