Potency-enhancing drugs that contain so-called PDE5 inhibitors, including Viagra, may have a cancer-inhibiting potential and improve the prognosis for men with colon and rectal cancer, a new Swedish study shows.
Previous preclinical studies have suggested that PDE5 inhibitors may inhibit tumor growth and tumor development in mice.
By comparing medical register data in Sweden, the researchers at the Center for Primary Care Research wanted to investigate whether the same applies to humans. They therefore coordinated nationwide registers with male patients with colorectal cancer, where some used the drugs after their cancer diagnosis. The comparison showed that 10.2 percent of patients with colorectal cancer who received PDE5 inhibitors died during the follow-up period, compared with 17.5 of those who did not receive the same inhibitors.
After adjusting for other clinical interference factors, the researchers concluded that the relative risk of death from colorectal cancer was 18 percent lower in patients receiving PDE5 inhibitors. The risk of metastases also decreased.
- We have also come to the conclusion that the anti-cancer effect is even stronger in patients who have undergone open surgery, says Wuqing Huang, one of the researchers behind the study.
But much research remains before the new findings can be put into practice.
- The biological mechanisms behind the anti-cancer effect are largely unknown, so further studies should be done to explore them, says Wuqing Huang.
The Center for Primary Care Research is a collaboration between Lund University and Region Skåne.
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