Thousands of Victorians could be living with undiagnosed cancer as people forget or choose not to undergo regular screening.

There was a 3.6 per cent decline in new cancer diagnoses in 2022 compared to 2021, according to the Victorian Cancer Registry report released on Thursday.

It was estimated there were 6660 fewer diagnoses than expected in the years between 2020 and 2022, the Cancer in Victoria report states.

"We know that during the pandemic, people put off seeking medical advice and their approach to health changed, only seeking help for serious, acute issues," Cancer Council Victoria chief executive Todd Harper said.

"Many Victorians are continuing to delay or are hesitant to book appointments with their doctor to discuss cancer symptoms or for cancer screening as they believe they will not be able to access a health system that they consider is overburdened."

Mr Harper said health professionals wanted to see Victorians if they noticed any concerning changes.

"It's still crucial that Victorians visit their general practitioner if concerned about their health and to get up to date with screening when due," he said.

"Thanks to improvements in the way we detect and treat cancer, the five-year survival rate for Victorians diagnosed with cancer has increased by 48 per cent over the past 30 years."

Overall, 36,299 cancers were diagnosed in 35,656 Victorians last year.

One in eight cancers diagnosed in Victoria is a blood cancer, accounting for about 13 per cent of cancers diagnosed in 2022.

"In good news, the five-year survival rate continues to improve for all blood cancers," Victorian Cancer Registry director Sue Evans said.

"Rates of blood cancer deaths are declining by more than two per cent annually."

The Cancer in Victoria report also found cancer was the cause of death for nearly one third of Victorians.

Lung, bowel, pancreas, prostate, and breast cancers are the leading causes of cancer death, which together account for just over half of all fatalities.