A new study suggests that giving lung cancer treatment in the morning could help patients live longer and slow down the growth of their cancer.
The research looked at people with advanced lung cancer who were receiving a type of treatment called immunochemotherapy.
This treatment uses both chemotherapy and drugs that help the immune system fight cancer. The researchers found that patients who received their treatment before 3 p.m. had better outcomes than those who received it later in the day.
The study, led by Yongchang Zhang and his team, involved 210 people with advanced non–small-cell lung cancer, which is one of the most common types of lung cancer. These patients had not yet started any treatment.
The team randomly divided the patients into two groups. One group received their treatment in the morning, before 3 p.m., and the other group received it at or after 3 p.m. This schedule was followed for the first four treatment cycles.
After following the patients for nearly 29 months, the researchers found that the morning group had much better results. On average, their cancer did not get worse for about 11.3 months.
In comparison, the afternoon group only went 5.7 months without their cancer progressing. This is called progression-free survival, which is an important measure of how well a treatment works.
The researchers also looked at overall survival, which means how long the patients lived. The morning group lived an average of 28 months, while the afternoon group lived around 16.8 months. These results suggest that simply getting treatment earlier in the day could make a big difference.
The study also showed that more people in the morning group responded well to the treatment—about 69.5%—compared to 56.2% in the afternoon group. Importantly, both groups had similar side effects, meaning the timing of the treatment didn’t make it more dangerous.
The researchers believe the body’s internal clock, known as the circadian rhythm, may explain why morning treatments work better. Our bodies have a natural 24-hour cycle that affects many functions, including how the immune system works.
Earlier studies in other types of cancer, like kidney cancer and melanoma, had suggested that the time of day might affect how well the immune system responds to treatment. However, this study is one of the first large trials to test this idea in a controlled way.
They also found that patients in the morning group had more active immune cells, especially CD8⁺ T cells, which help fight cancer. These cells were not only more active but also in better condition, meaning they were more likely to attack cancer cells and less likely to be worn out.
Although the results are promising, the researchers say more studies are needed. One limitation is that all the patients in this study were from China. So, scientists still need to test if the same results happen in people from other countries. Also, more research is needed to fully understand how the body’s clock affects cancer treatment.
Still, this study gives hope that something as simple as choosing the right time of day for treatment could help cancer patients. It’s a cost-free change that could improve survival and quality of life. If future research confirms these results, it might change how doctors around the world schedule cancer treatments.
If you care about lung health, please read studies about marijuana’s effects on lung health, and why some non-smokers get lung disease and some heavy smokers do not.
For more information about health, please see recent studies that olive oil may help you live longer, and vitamin D could help lower the risk of autoimmune diseases.
The study is published in Nature Medicine.
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