"There's a lot of medical knowledge that when shared across borders will benefit the global healthcare system," Sermo's CEO Peter Kirk, told CNBC by phone.
For Armstrong who joined the service in 2007, Sermo has been "life-changing" for many of his patients who may not have otherwise had access to specialist expert knowledge. In the case of the thyroid cancer patient, the doctor posted details of the problem. Within the first 24 hours, Armstrong received 40 replies from colleagues across the U.S.
Eventually the patient landed in a research program at the University of Michigan and is now a seven-year survivor of the cancer.
Over the last year, 3,500 challenging patient cases were posted by doctors on Sermo. These cases were viewed 700,000 times and received 50,000 comments, the social network claims.
Sermo is not the only platform for doctors to share insights. Figure1 allows physicians to post pictures of diseases with fellow doctors posting responses for cures or identification of the condition. Another called SharePractice allows doctors to crowd source answers to medical problems, much like Sermo. Doximity is a professional network, sort of like a LinkedIn for doctors. And as well as the medical-specific social networking sites, doctors are also on LinkedIn and Facebook.
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But Sermo's CEO said the ability for doctors to remain anonymous on the platform is one of the key features for its 305,000 U.S. users.
"Doctors can use different social networks. They use Facebook for personal networking, many are on LinkedIn and so there are a number of different sites where they can do different things," Kirk told CNBC.
"But on Sermo, you can choose to be anonymous and more straightforward to the point where we have seen more doctors admit mistakes," Kirk said.
The U.K. launch marks Sermo's international expansion. Kirk said that other European markets such as Germany, France, Italy and Spain are next.
"For us it is about taking medical crowdsourcing to the next level," the CEO said.