Dr. Edmund M. Chao's team at the University of California, San Diego (UCSD) announced at the American Society for Radiation Oncology (ASTRO) annual conference held in Boston on the 29th that they analyzed medical data from more than 265,000 patients with six cancers and confirmed this relationship between depression, cancer death risk, and mental health treatment.
Dr. Chao said, “This study shows that it is important to identify patients who need mental health treatment early and provide appropriate treatment quickly in cancer treatment,” adding that there is a need to prepare individualized mental health support measures for each patient in cancer treatment.
The research team pointed out that although depressive disorder occurs in 20% of cancer patients and is associated with worsening cancer treatment outcomes, it is not easy to detect because the symptoms overlap with symptoms that appear during the cancer itself or during the treatment process, and mental health services are not sufficiently integrated into cancer treatment.
The research team used the National Cancer Institute's (NCI) Surveillance, Epidemiology, and End Results (SEER) data and Medicare data to investigate whether depression is associated with cancer mortality and whether the results vary depending on the type of mental health treatment and when treatment is started.
The subjects of analysis were 265,639 Medicare beneficiaries aged 66 or older who were diagnosed with breast, colon, prostate, bladder, kidney, and non-small cell lung cancer between 2010 and 2017, of whom 22% were diagnosed with major depressive disorder.
We investigated psychological treatment and drug treatment for depressive disorder, and analyzed the relationship between receiving mental health treatment within 4 weeks after cancer diagnosis and cancer mortality. Additional analysis was also performed at 8 and 12 weeks.
The results showed that patients with both cancer and depression had an 11% higher risk of cancer death than cancer patients without depression. Cancer mortality rates 1 year and 5 years after cancer diagnosis were 29% and 43%, respectively, in patients with depression, but 21% and 35% in patients without depression.
On the other hand, if depressed patients received psychological treatment within 4 weeks of their cancer diagnosis, the risk of cancer death was 21% lower than patients who did not receive psychological treatment during this period.
When the timing of psychological treatment was expanded to 8 and 12 weeks, the risk of cancer death was lowered by 13% and 12%, respectively. As the timing of treatment was delayed, the correlation between psychological treatment and reduced risk of death became smaller.
However, among cancer patients with depression, only 3% received psychological treatment within 4 weeks of diagnosis, and even when expanded to 12 weeks, only 4.6%.
Antidepressants were used much more than psychotherapy, with 32.5% of patients using them within 4 weeks of cancer diagnosis, but when analyzing all cancer patients, antidepressant use was not associated with a reduction in cancer mortality.
Additionally, the association between psychotherapy and reduced risk of cancer death differed depending on the type of cancer, and was statistically significant in prostate, breast, and kidney cancer. Drug treatment was significantly associated with a reduction in cancer mortality only in prostate cancer patients.
The research team explained that these differences show that the relationship between mental health and treatment outcomes in cancer patients is not simple, and that necessary mental health support and effective intervention methods may vary depending on the type of cancer, prognosis, and treatment process.
However, because this study was a retrospective observational study that analyzed already collected medical data, it did not prove a causal relationship that psychotherapy directly lowers the risk of cancer death.
Dr. Chao said, "In cancer treatment, depression is easy to miss because fatigue, difficulty concentrating, and loss of interest overlap with the effects of cancer or treatment. If depression goes undetected or is not treated, it can add another layer of difficulty at a time when patients need a lot of support."
◆ Source: ASTRO 2026 Annual Meeting, Edmund M. Qiao et al., 'Role of Early Mental Health Interventions on Cancer Mortality for Patients with Depression', https://amportal.astro.org/sessions/ss-18-22867/role-of-early-mental-health-interventions-on-cancer-mortality-for-patients-with-depression-111078
