On Wednesday, a leaked document revealed a private-public sector consortium was the last remaining bidder for a Â£690m contract.
Campaigners handed over their petition at a clinical commissioning group (CCG) meeting on Thursday.
Commissioners said their focus was on improving outcomes for patients.
Speaking at a protest outside the NHS meeting in Hednesford, Gail Gregory, from the Cancer Not For Profit campaign group said the Staffordshire service should be run by the NHS.
"A private company is out to make a profit. That's what you want a private company to do. I'm not a profit opportunity, I'm a patient," she said.
Outsourcing contracts to cover both cancer and end of life care in Staffordshire were announced last year. Together, they are expected to be worth Â£1.2bn and cover a 10-year period.
The contracts will cover the areas controlled by Stafford and Surrounds, Cannock Chase, Stoke-on-Trent and North Staffordshire CCGs.
The cancer contract is expected to be awarded in December and, according to a leaked document seen by the BBC, discussions between the CCGs and the consortium are expected to take place over the next few weeks, before a formal proposal is submitted.
The group includes University Hospitals North Midlands, the Royal Wolverhampton Hospitals Trust and private firm Interserve.
The CCGs said they brought together a wide range of expertise.

Dr Hawley Harvey Crippen was executed in November 1910 after poisoning his wife and hiding her dismembered remains under the cellar floor.
He was caught as he tried to escape to Canada with his mistress, Ethel Le Neve, who was disguised as a boy.
The letters, written while he was in prison and sold in Wiltshire, would remain in the UK, auctioneers said.
Auctioneer Andrew Aldridge described the atmosphere in the saleroom as "frantic" with bidders calling in from Australia and the United States.
He said the letters provided a "fascinating insight" into Dr Crippen's mind during the last few days of his life.
One of his final letters, written to Lady Henry Somerset on 26 October 1910 - less than a month before he was executed - details his relationship with his mistress and his view that "all yet may come right".
Crippen was hanged at Pentonville prison, in London, on 23 November 1910, after an appeal against his sentence failed.
He became the first criminal to be captured with the aid of wireless communication, after the captain of the ship he was escaping on to Canada, the SS Montrose, became suspicious.
The ship's captain sent a telegraph message informing the owners he believed Crippen was on board.
The infamous killer's letters, which are being sold by a private collector, had been expected to make between £3,000 and £5,000 in the sale at Henry Aldridge and Son auctioneers.

Iron ore delivered into China fell 8.3% on Monday after Beijing reported weak export data over the weekend.
China is one of the biggest consumers of the commodity and there are concerns a slowdown in its economy may hurt demand and impact miners' profits.
Shares of BHP Billiton, Rio Tinto and Glencore Xstrata all fell.
Rio Tinto shares ended the day down by 5.7%, while BHP Billiton fell more than 4% on the Australian Securities Exchange.
Fortescue Metals tumbled nearly 10% in Sydney on Monday.
Mining stocks listed in London were also hurt, with Anglo American, Antofagasta and Glencore Xstrata all down by more than 2%.
Recent demand for minerals like iron ore and copper has been driven in part by China's export boom, as well as government-led infrastructure spending.
That has seen miners become increasingly dependent on China for growth.
However, over the weekend, China reported a surprise 18.1% fall in exports for February, compared to the same month last year.
A fall in China's steel futures also hurt mining shares because iron ore is a key ingredient in steel manufacture.
Fears of slowing demand from China have added to slides in other commodity prices, like that of copper, which has dropped to its lowest level in more than seven months.
China is the biggest buyer of the metal, which is used in electronics production and other manufacturing industries.
"Any poor news from China is always going to hit short-term market sentiment, especially in the mining sector, and fears of slower growth will hit base metals," said Steven Mayne, director at IPR Capital.
More than 63,000 people have signed a petition against what they say is the privatisation of cancer care in Staffordshire.
[NEXT_CONCEPT]
Letters written by one of the 20th Century's most notorious murderers have been sold for £11,000 at auction.
[NEXT_CONCEPT]
Shares in some of the world's biggest mining companies have been hit by a slump in the price of iron ore, amid fears of a slowdown in China's economy.