Mike Weatherley, the Conservative MP for Hove, is to stand down at the next election.
Mr Weatherley, 57, was elected at the last general election in 2010 and has served as Prime Minister David Cameron’s intellectual property (IP) adviser since last September.
He suffered cancer of the oesophagus two years ago and needed major surgery but has never spoken publicly about his health.
Mr Weatherley, a chartered management accountant, is expected to return to the creative industries having worked as the European vice-president of the Motion Picture Licensing Company before becoming an MP.
He started Rock the House in 2010, Parliament’s biggest competition, which raises awareness of intellectual property rights and the importance of live music while encouraging young talent.
He also launched a similar competition, Film the House, with this year’s winners of both competitions being announced earlier this week.
Mr Weatherley also successfully campaigned for a change in the law to criminalise squatting in people’s homes.
In a letter to the Prime Minister today (Thursday 3 July) he wrote: “It is after profound consideration that I write to inform you that I will not be standing for re-election at the general election in 2015.
“I have nothing but huge admiration for the work of the government over the past four years, including what has been done to get our economy back on track.
“In Hove and Portslade this has translated to a drop in unemployment of a staggering 37.5 per cent.
“I am strongly in favour too of our efforts to reform our membership of the EU but even more so of our pledge of a referendum in 2017 as I have mentioned to you directly on a number of occasions.
“In terms of my own work, I have proudly served on the Administration and Justice Select Committees.
“I have campaigned relentlessly, with much success, to bring common sense to our laws on residential squatting.
“I have fought hard on a number of animal rights issues and firmly believe that the hunting ban should remain in place.
“I have also highlighted the dangers of nuclear power and, indeed, the benefits of solar and other renewables.
“Over the past year, I have taken immense pride in serving as your Intellectual Property Adviser.
“I am sure that you will agree that we have made huge steps towards really getting politicians and industry talking – which is key to making the most of our country’s wealth of creative talent.
“It would be a privilege to continue offering my assistance in this regard.
“It goes without saying that my years representing the wonderful people of Hove and Portslade have been one of the most fulfilling periods of my life which I will look back on with very fond memories.
“I have made so many friends over the years including so many of my loyal supporters both in and out of Brighton and Hove Conservatives. I cannot thank them enough.
“Ultimately, beating cancer two years ago has led me to review what I want for the future. It has been the toughest decision of my life but I do feel that now is the time to move on.”
Linda Freedman, chairman of Brighton and Hove Conservatives, said: “We are all incredibly sad that Mike won’t be restanding.
“He has been a seriously effective representative for Hove and Portslade over the past four years.
“Nothing stands still in politics though so our discussions as to what happens next are already far advanced. We’ll be making an announcement on this point shortly.”
