The number of people globally requiring chemotherapy will increase from 9.8 million in 2018 to 15 million by 2040, an international study predicted on Thursday.
Population growth was the main factor behind the increase shown in the study, and developing countries are predicted to account for 75 percent of additional cases.
Those responsible for the study have called for an expansion of services to deal with demand.
"Strategies are urgently needed to equip the global health workforce to enable safe treatment of current and future patients," lead author Dr Brooke Wilson from Australia's University of New South Wales (UNSW) said.
"Countries and institutions should use our data to estimate their future cancer physician workforce requirements and chemotherapy needs and plan national, regional, and global strategies to ensure all those who need it will have access to chemotherapy treatment."
Wilson said demand for physicians will sharply increase from 65,000 in 2018, to 100,000 in 2040.
The study also looked at the spread and location of anticipated new cases, with low and middle income countries tipped to see the biggest increases.
Large parts of Africa are estimated to see more than a 100 percent increase in cases requiring chemotherapy by 2040, while West Asia is expected to see a 99 percent increase.
According to the figures, the most common cancers requiring chemotherapy in 2040 will be lung with a 16.4 percent increase to 2.5 million cases, followed by breast cancer and colorectal cancer. Enditem