Can Chemo Benefit Older Patients With Pancreatic Cancer?

TOPLINE:

Some vulnerable older patients with untreated metastatic pancreatic cancer can benefit from chemotherapy, but only if they can tolerate enough cycles of treatment, according to results of the randomized phase 2 GIANT study.

METHODOLOGY:

• Pancreatic cancer is most often diagnosed in adults aged 65 years or older. Providing cancer treatment for this older, often vulnerable, population comes with significant challenges and can lead to worse survival.
• To examine real-world outcomes of older adults with untreated metastatic pancreatic cancer, researchers recruited patients aged 70 years or older and performed a geriatric assessment to identify comorbidities, cognitive issues, and other geriatric abnormalities.
• Those who were deemed “fit” (ie, with no geriatric abnormalities) were assigned to receive off-study standard-of-care treatment, whereas those classified as “frail” (ie, with severe abnormalities) received off-study supportive care.
• The remaining 176 “vulnerable” patients with mild to moderate geriatric abnormalities completed a geriatric and quality-of-life assessment and were then randomly assigned to receive either dose-reduced 5-fluorouracil (5-FU), leucovorin plus liposomal irinotecan (n = 88) or modified gemcitabine plus nab-paclitaxel (n = 88) every 2 weeks. Ultimately, 79 patients started the 5-FU combination and 75 received gemcitabine plus nab-paclitaxel. Patients were assessed every 8 weeks until disease progression or intolerance.
• Overall, patients had a median age of 77 years; 61.9% were aged 75 years or older. About half were female, and 81.5% were White. The majority (87.5%) had a performance status of 0 or 1.

TAKEAWAY:

• Median overall survival was 4.7 months in the gemcitabine plus nab-paclitaxel arm and 4.4 months in the 5-FU combination group, with no significant survival difference observed between the two arms (P = .72).
• When the overall survival analysis was restricted to patients who received at least 4 weeks, or two cycles, of treatment (about 62% of patients), the median overall survival across the two treatment arms reached 8.0 months, in line with expectations for these regimens.
• Patient stratification revealed that those with a performance status of 2 had significantly worse overall survival than those with a status of 0: 1.4 months vs 6.9 months, respectively (hazard ratio [HR], 2.77; P 
• Overall, more than half of patients experienced grade 3 or higher adverse events. Just over 38% of patients received only one to three cycles of therapy, whereas 26% remained on treatment for 12 or more cycles. The adverse event rates were similar between the two regimens, but the toxicity profile was slightly different — the researchers, for instance, observed more peripheral neuropathy with gemcitabine plus nab-paclitaxel and more diarrhea in the 5-FU combination arm.

IN PRACTICE:

Overall, the “survival outcomes among vulnerable older patients were lower than expected, with high percentage of patients not able to start treatment, or complete one month of therapy due to clinical deterioration,” said study presenter Efrat Dotan, MD, Chief, Division of Gastrointestinal Medical Oncology, Fox Chase Cancer Center, Philadelphia. 

“For vulnerable older adults who can tolerate treatment, these two regimens provide clinicians with options for tailoring therapy based on toxicity profile,” Dotan added. But “tools are needed to better identify patients who can benefit from treatment.”

The results underline the need to perform geriatric assessments, as opposed to merely looking at performance status, commented David F. Chang, PhD, MS, MBBS, professor of Surgical Oncology, University of Glasgow, Scotland, who was not involved in the study. 

SOURCE:

The research, presented at the 2024 American Society of Clinical Oncology Annual Meeting, was funded by the National Cancer Institute and the Eastern Cooperative Oncology Group.

LIMITATIONS:

Chang noted that the study did not reveal which treatment regimen was more effective.

DISCLOSURES:

Dotan declared relationships with Agenus, Amgen, G1 Therapeutics, Incyte, Olympus, and Taiho Pharmaceutical and institutional relationships with Dragonfly Therapeutics, Gilead Sciences, Ipsen, Kinnate Biopharma, Leap Therapeutics, Lilly, Lutris, NGM Biopharmaceuticals, Relay Therapeutics, and Zymeworks. Chang declared relationships with Immodulon Therapeutics and Mylan and institutional relationships with AstraZeneca, BMS GmbH & Co. KG, Immodulon Therapeutics, and Merck.