“One size fits all” may work for socks and neckties, but not for prostate cancer surgery. That seems to be the message coming out of the Gustave Roussy Cancer Campus in Paris. Scientists there completed a clinical trial – the first of its kind – that showed that precision medicine – or tailoring treatment for individual people – can slow down the time it takes for a tumor to grow back.

The doctors presented their work at the Molecular Analysis for Personalized Therapy conference.

The results from the trial indicated that 199 out of 1110 patients with advanced cancer, who had their genes mapped to look for mutations that could be targeted with drugs, including experimental therapies, and their treatment tailored, had about a 30 percent longer grace period before their cancer started growing again. This was as compared to any of the previous therapies the patients had tried. This ranged from between five and 32 months.

The trials enrolled patients with a number of advanced cancers, including prostate, lung, breast, neck and head, lung, stomach, bladder, and bowel cancer. It is the first of its kind to demonstrate that so-called “precision medicine” can increase the time it takes for a tumor to grow back, and also that this benefit holds true in a variety of cancer types.

“The great thing about this is that it’s not just for one type of cancer — patients with many different types of cancer could benefit from this [precision treatment] in the future,” said Christophe Massard, head of the early drug development multidisciplinary committee at Gustave Roussy.

This trials were for “last chancers:” patients who had no other treatment options left and who had already tried three or more cancer therapies. The team found potential faulty molecules to target for 411 of these patients and experimental drugs to hit the targets for 199 of these patients.

Professor Jean Charles Soria, principal investigator of the trial from the Gustave Roussy Cancer Campus, said: "This is the first precision medicine trial to show that analyzing a person's DNA improves treatment options for patients with late stage cancer. And these results are particularly exciting because in some cases we were testing experimental drugs, and found that we could slow down the growth of tumors in around one in five patients with advanced cancer."