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Older Women With High-risk Breast Cancer May Not Need Chemotherapy

Adding chemotherapy to hormone therapy after surgery did not improve survival in women over age 70 with high-risk hormone receptor-positive breast cancer, according to a study in the Lancet. The study included 1,089 women who received genomic testing to assess their risk of recurrence. The women were divided into two groups: one that received hormone therapy alone and another that received hormone therapy and chemotherapy. In the people who received both chemotherapy and hormone therapy, the overall survival was 90.5% at four years and 72.7% at eight years, compared with 89.3% and 68.3%, respectively, in the group that received only hormone therapy, MedPage Today reported. More women in the group that received chemotherapy reported severe toxicity. In fact, 52 (9%) of 548 people in the no chemotherapy group experienced at least one grade 3 or higher side effect, indicating that the effect interfered with daily activities and required treatment or hospitalization. Grade 3 effects were seen in 183 (34%) of 541 people in the chemotherapy group. Authors of an accompanying editorial in the Lancet said the study provides perspective about a patient population that has been historically excluded from clinical trials because of their age. The editorial also noted limitations in the study’s ability to analyze subgroups in the population, and the authors suggested that treatment decisions going forward will require nuance. “The comprehensive dataset will assist older women in balancing quantity and quality of life when considering chemotherapy to treat their high-risk, estrogen receptor-positive, HER2-negative early breast cancer,” medical oncologist Sabine C. Linn and researcher Florentine S. Hilbers, both of the Netherlands Cancer Institute in Amsterdam, wrote in the editorial.

Immune Response Linked to Outcomes in Early Trial of Pancreatic Cancer Vaccine

Twenty-one of 25 people with pancreatic or colorectal cancer mounted immune responses after receiving an off-the-shelf vaccine, according to a phase I clinical trial published in Nature Medicine. People who had strong immune responses, in which their immune systems seemed to identify KRAS mutations and other targets on the cancer cells, also lived the longest after the treatment, the study found. While personalized vaccines for cancer treatment require genomic profiling of the tumor, the vaccine in the study, called ELI-002 2P, used short chains of amino acids called peptides to help the immune cells recognize and fight cells with KRAS mutations. In the study, people with pancreatic cancer survived for an average of 29 months and lived recurrence-free for more than 15 months post-vaccination, NBC News reported, which suggests progress in a particularly difficult-to-treat disease. “That far exceeds the rates with resectable cancers,” Zev Wainberg, a medical oncologist at UCLA Health in Los Angeles and study co-leader, told NBC News.

Genetic Testing in Gastrointestinal Cancers Reduces Risk of Chemotherapy Side Effects

A study found testing people with gastrointestinal cancer for genetic changes associated with increased chemotherapy toxicity could guide decisions prior to starting treatment. The study, which was published in JCO Precision Oncology, also found testing reduced the risk of serious side effects in patients. Participants were tested for two gene variants: a DPYD variant that hinders the body’s ability to process fluoropyrimidines, such as fluorouracil and Xeloda (capecitabine), which can cause these chemotherapies to build up in the body to toxic levels, and a UGT1A1 variant that causes people to metabolize the chemotherapy irinotecan slowly, which can result in severe diarrhea or low white blood counts. Compared with records of gastrointestinal cancers patients who had the same mutations and received standard chemotherapy, people who had a tailored dose of chemotherapy based on genetic testing had fewer treatment modifications (38% vs 76%), as well as fewer severe treatment-related adverse events (38% vs 65%) and treatment discontinuations (31% vs 47%), MedPage Today reported. However, getting timely genomic testing results for this purpose is a challenge. For this study, researchers developed an assay able to produce results in seven to 10 days, and the median time to receive testing results was about 10 days. Just over half of the results came back before the patient was scheduled to start chemotherapy, Sony Tuteja, a clinician-scientist at Penn Medicine in Philadelphia, told MedPage Today. Of the 288 patients who were tested, 16 had one of the variants that would affect their treatment and received a dose adjustment. “Our study and others have shown that a good way to safely provide these chemotherapy drugs to patients who carry these variants is to test them before treatment and do the dose reductions prior to the first dose,” Tuteja said. “But we really have to create the clinical workflows and infrastructures to support genetic testing in clinical care to make it easy for the clinicians to use it.” Genetic testing for the DPYD variant is recommended through treatment guidelines for colon cancer in Europe but not in the U.S., MedPage Today reported.