Fasting During Chemotherapy May Improve Outcomes in Ovarian Cancer: Study
Italy: A small randomized study from Italy found that patients with ovarian cancer who fasted during chemotherapy experienced significantly longer progression-free survival (PFS) compared with those who continued a normal diet, suggesting fasting may enhance treatment effectiveness.
The findings were presented at the 2026 ASCO (American Society of Clinical Oncology) Annual Meeting by Claudia Marchetti from Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Rome, on May 30, 2026. It was subsequently published in the Journal of Clinical Oncology. The pilot trial explored whether short-term fasting (STF) around chemotherapy cycles could influence metabolic responses, treatment efficacy, and immune parameters in women with advanced ovarian cancer.
Researchers have hypothesized that temporary fasting may improve chemotherapy response by lowering insulin levels and reducing insulin-driven survival signaling pathways in cancer cells. However, robust clinical evidence in ovarian cancer has been limited, prompting this prospective randomized study.
The trial included women with advanced high-grade serous ovarian cancer receiving neoadjuvant chemotherapy with carboplatin and paclitaxel. Participants were randomized to either a short-term fasting regimen or a regular unrestricted diet. The fasting group abstained from food for 36 hours before and 24 hours after each chemotherapy cycle. Eligible patients had a BMI of at least 19 kg/m², while those with diabetes, eating disorders, or food allergies were excluded. The primary outcome was the change in insulin levels after three chemotherapy cycles, with progression-free survival and immune parameters assessed as secondary and exploratory endpoints.
The trial revealed the following findings:
- A total of 36 patients completed the study, with 18 participants in each treatment arm.
- Baseline clinical characteristics and insulin levels were comparable between the short-term fasting group and the free diet group.
- After three chemotherapy cycles, insulin levels increased in the free diet group but decreased in the fasting group, with a statistically significant difference between the two arms.
- Among patients undergoing interval cytoreductive surgery, those in the fasting arm showed a higher rate of strong pathological response, with more patients achieving a chemotherapy response score of 3 compared with the free diet group.
- At a median follow-up of approximately 18 months, progression-free survival was longer in the fasting group (38 months) compared with the control group (24 months), and the difference was statistically significant.
- Translational analyses suggested that short-term fasting was associated with modulation of immune response, including a reduction in immunosuppressive immune cell subsets linked to poorer chemotherapy outcomes.
- The study met its primary metabolic endpoint, demonstrating a significant reduction in insulin levels with short-term fasting compared to a free diet.
- Overall, short-term fasting was associated with favorable metabolic changes, improved pathological response signals, immune modulation, and longer disease control in this pilot study.
The researchers concluded that while these early results are encouraging, larger randomized trials are needed to confirm the benefits and further evaluate the safety, feasibility, and long-term impact of short-term fasting in the treatment of ovarian cancer.
Reference:
J Clin Oncol 44, 2026 (suppl 16; abstr 5517). DOI: 10.1200/JCO.2026.44.16_suppl.5517
Next Story