In some areas, patients are twice as likely to be found suffering from the disease during an emergency hospital admission than in the best performing parts of the country.
Nearly one in five people in the region amounting to around 5,500 patients in 2018-19 were found to have cancer following emergency admissions out of 28,100 cases of the illness diagnosed.
But in Hull, the Heavy Woollen area in West Yorkshire, and central Bradford, this rose to around one in four patients, compared to fewer than one in seven in the Harrogate district – one of the lowest rates in England.
NHS leaders are urging people with concerning symptoms to seek help earlier to give them a better chance of successful treatment if they go on to be diagnosed with cancer.
Latest figures published by Public Health England show 300 people were diagnosed in an emergency in Hull in the 12 months to March among more than 1,200 people found to have cancer.
A similar proportion totalling 200 people were diagnosed over the period in North Kirklees. The highest rates in the country of cases found in an emergency were in central Bradford although overall numbers of 50 patients were small.
In contrast, only 140 people out of 1,050 with the disease were diagnosed in the Harrogate district following an unexpected hospital admission.
There have been significant improvements in some parts of the region in the last four years, with rates of emergency diagnosis falling by around a quarter in Sheffield and Rotherham.
But there has been no change in other parts including Hull, Scarborough and Ryedale, and rates of cases detected in an emergency have even risen in Bradford, North Kirklees, Calderdale and North East Lincolnshire.
Across England, only Greater Manchester had higher rates of emergency diagnosis of the disease than west and south Yorkshire during 2018-19.
In a statement, NHS officials at Hull Clinical Commissioning Group (CCG), said work was underway to try to increase awareness of symptoms through a network of hundreds of cancer champions in the city.
“Hull is a city that has higher than average levels of deprivation and health inequalities which are recognised to be linked with increased cases of cancer,” said a spokesman.
“There are challenges around supporting people to recognise and seek advice for symptoms that could potentially point towards possible cancers, some of which are related to people’s level of understanding around their own health, symptoms and conditions.”
GP Ian Fenwick, clinical lead for cancer at Bradford City CCG, said a new cancer strategy had been drawn up including work to improve higher uptake of screening programmes.
He said: “We are aware of the challenges we face when it comes to cancer. Action plans will be developed in collaboration with all our partners to ensure any issues are addressed.”
NHS North Kirklees CCG said work was underway to raise awareness of the signs and symptoms of cancer and increase uptake of screening programmes including bowel cancer. A pop-up cervical screening clinic was being planned and lung health checks were due to begin next year.
Overall figures reveal fewer than two in five patients are diagnosed with cancer following urgent referral to hospital under official national two-week waiting time standards. Almost one in five cases are detected in an emergency admission and the remainder after checks for “vague” symptoms which could indicate a range of conditions including unexplained weight loss, pain or fatigue.