De-escalating surgery
Also at the session, Jennifer Tseng, MD, medical director of breast surgery at City of Hope Orange County Cancer Center, Irvine, Calif., discussed de-escalation of locoregional therapy. For some patients, this may mean skipping surgery or radiation.
“How do we de-escalate the extent of surgery, the extent of morbidity that we are imparting on our patients with surgery but still maximizing and preserving oncological outcomes?” she asked.
Currently more than 30% of new breast cancer diagnoses are in women age 70 and older, and estrogen receptor positive, HER2-negative disease is the majority biomarker profile.
At present, more than 70% of women with breast cancer in this older population will receive axillary surgery and/or radiation.
But for many patients with early, node-negative breast cancers with favorable tumor characteristics, less extensive surgery may be an appropriate option, especially for patients who have other significant comorbidities, Dr. Tseng said.
“Just at baseline, we know that mastectomy is a harder operation, it’s a harder recovery. You may be incorporating additional surgery such as reconstructive surgery, so breast-conserving surgery is always considered less invasive, less morbid,” she said.
“Do we absolutely have to do a mastectomy for a patient who has a second episode of cancer in the same breast? The answer is no,” she said, adding that omitting axillary surgery in early-stage disease may also be safe for some older patients.
De-escalating radiotherapy
Options for de-escalating radiation therapy include shortening the course of treatment with hypofractionation or ultra hypofractionation, reduction of treatment volumes with partial breast radiation, reducing radiation dose to normal tissues, or even in appropriate cases eliminating radiation entirely, Dr. Tseng said.
“My radiation oncologist turned to me and said, ‘This patient is now eligible for 3 days [or radiation] based on the latest trial we have open at City of Hope.’ I was like, wow, we went from 6 weeks to 3 days of radiation, but that is in the appropriate patient population with those early stage, really more favorable tumor characteristics,” she said.
Moving forward, the debate in radiation oncology is likely to focus on the option of ultra hypofractionation vs no radiation, she added.
Regarding reducing radiation volume, Dr. Tseng noted that most in-breast tumor recurrences happen within 1 cm of the original tumor bed, and partial breast irradiation targets the tumor bed with a 1- to 2-cm margin and provides excellent clinical outcomes with minimal adverse events, allowing for rapid recovery.
Deep inspiration breath holds and prone-positioning of patients with left-side tumors during beam delivery can also significantly decrease the dose to normal tissues, an especially important consideration for patients with cardiopulmonary comorbidities, she said.
Radiation may also be deferred in many older patients who may benefit from endocrine therapy alone and in those who have a very early stage and less aggressive tumor type.
Systemic therapy in the older patient
Etienne GC Brain, PhD, of the department of medical oncology at the Curie Institute in Paris and Saint-Cloud, France, reviewed evidence regarding systemic therapy in older patients with high-risk breast cancers.
For patients with triple-negative breast cancer pathologic stage T1b or greater he usually advises adjuvant chemotherapy with the option of neoadjuvant chemotherapy if breast-conserving surgery is a goal; for patients with HER2-positive disease, he advises 1 year of therapy with an anti-HER2 agent.
Shorter HER2 regimens may be possible for older patients, and frail older adults may have good outcomes with HER2 therapy alone, as shown recently by Japanese investigators, Dr. Brain noted.
“For lumimal disease, endocrine therapy remains the standard of treatment for me, and chemo, of course can be considered in higher risk, but the problem is we don’t know how to define this high risk, given the poor guidance provided by gene expression profiles,” he said.
For older patients, longer follow-up is needed to assess treatment benefit vs. life expectancy, Dr. Brain said, warning that the standard of care established in younger patients cannot be easily extrapolated to the care of older patients.
Dr. Schonberg disclosed authorship of review pages on preventive health for older adults for UpToDate. Dr. Tseng disclosed that she is a breast surgeon and that her discussion of radiation therapy may reflect personal bias. Dr. Brain disclosed honoraria from Lilly, Pfizer, and Seagen, consulting/advising for Daiichi Sankyo, AstraZeneca, Pfizer, and Sandoz-Novartis, and travel expenses from Pfizer.
A version of this article first appeared on Medscape.com.