The latest Global Cancer Observatory (GLOBOCAN) estimates have highlighted widening inequalities in cancer prevention, diagnosis and treatment globally, with an estimated 20.6 million new cancer cases and 9.8 million cancer deaths recorded in 2024.
The report by the International Agency for Research on Cancer (IARC), released as the agency marked its 60th anniversary, projects that annual new cancer cases could rise to 34 million by 2050, while cancer deaths could reach 17.5 million if incidence and mortality rates are not reduced.
The findings come as the American Cancer Society (ACS) and cancer experts have urged people to pay attention to unusual changes in their bodies and seek medical evaluation promptly, noting that early recognition of warning signs can facilitate timely diagnosis and treatment.
According to the ACS, common signs and symptoms that should not be ignored include persistent fatigue or extreme tiredness that does not improve with rest; unexplained weight loss or gain of 10 pounds or more; loss of appetite; mouth changes such as sores or difficulty swallowing; and swelling or lumps in the breast, lymph nodes or other parts of the body.
Other warning signs include persistent or worsening pain, particularly when it is new or has no known cause; changes in the skin, such as a new mole, changes in an existing mole or a sore that does not heal; persistent cough or hoarseness; and unusual bleeding or bruising without an apparent cause.
The society also lists persistent changes in bowel habits, including constipation or diarrhoea, changes in the appearance of stool or blood in the stool; bladder changes such as painful urination, blood in the urine or changes in urinary frequency; fever or night sweats; and unexplained headaches, vision or hearing problems, among other symptoms.
Speaking during an interview session of the Naija Cancer Watch Fellowship organised by Sebeccly Cancer Care, clinical and radiation oncologist, Dr Omolola Salako, said cancer warning signs vary according to the type and location of the disease.
Salako stressed the importance of recognising unusual changes early and seeking appropriate medical assessment. She explained that breast cancer could present as a painless lump in the breast, although some lumps may be painful.
Other warning signs, she said, include lumps around the armpit or collarbone, changes in the appearance or symmetry of the breast, redness or deep dimpling of the skin, and changes to the nipple.
Concerning prostate cancer, Salako identified significant changes in urination, including repeatedly waking at night to urinate, difficulty controlling urine and blood in the urine. She added that severe bone pain could occur when the disease has spread to the skeletal system.
The oncologist, however, cautioned that such symptoms do not necessarily indicate prostate cancer, as other medical conditions can cause similar changes, making proper medical assessment essential.
On cervical cancer, Salako identified abnormal vaginal bleeding as a major warning sign, particularly bleeding after sexual intercourse, between menstrual periods or after menopause.
Recognition of warning signs, apart, she emphasised the importance of understanding the risk factors that increase an individual’s likelihood of developing cancer.
The GLOBOCAN 2024 estimates also reveal profound geographic inequalities in the global cancer burden, driven by population size, ageing, exposure to risk factors and unequal access to prevention and quality cancer care.
China alone accounts for about one in four cancer cases and cancer deaths worldwide, while Europe, with just 9.2 per cent of the global population, accounts for more than 20 per cent of global cancer incidence.
The report shows that standardised cancer incidence rates vary by as much as threefold between countries, while mortality rates can vary by up to fivefold.
The highest incidence rates are recorded in countries including Australia and Denmark, while some of the lowest rates are observed in parts of sub-Saharan Africa.
Cancer mortality rates are highest in Eastern Europe and Melanesia, with particular countries standing out because of specific cancer profiles, including liver cancer in Mongolia and cervical cancer in Zimbabwe.
According to Freddie Bray, head of the Cancer Surveillance Branch at IARC, the disparities reflect not only differences in cancer risk but also inequalities in early detection, diagnosis and access to effective treatment.
He said the variations in cancer outcomes underscore the need for countries to strengthen cancer prevention, early detection and access to quality treatment, particularly in regions carrying a disproportionate burden of the disease.
