Oncological diseases have a great social impact, both in Portugal and in the rest of the world and their incidence has been increasing.
The determining factors for this increase are mainly a consequence of the aging of the population, but also determinants that can be modified, such as the adoption of a healthy lifestyle and vaccination.
According to the World Health Organization, oncological diseases are one of the leading causes of death, having been responsible in 2020 for almost 10 million deaths, that is, about one in every 6 deaths in the world. In Portugal, they occupy the second place in the main causes of death, after cardiovascular diseases, and have been the main cause of years of life lost.
With the investment in the diagnosis and treatment of oncological diseases, there was an improvement in the prognosis of these patients.
But in addition to improving health care, each individual can contribute to reversing the statistics. Adopting an active lifestyle, with physical activity, a diet rich in fruit and vegetables and fiber, as well as avoiding substances that are proven to be related, such as tobacco, alcohol and pollution, and carrying out screening tests at the recommended ages are contributions that we must all assume.
But there are also some viruses related to the emergence of oncological diseases and for these, another form of protection is available – vaccination.
HPV Virus and Cervical Cancer
The Human Papilloma Virus is proven to be linked to some types of cancer, namely of the cervix (with HPV being responsible for almost 100% of all cases), vagina, anus, vulva, penis and oropharynx and annually in Portugal more than 1000 cases of cervical cancer.
Since 2008, Portugal has included in the National Vaccination Program (PNV) the vaccine against HPV infections for girls and, since 2020, for boys. The PNV recommends its administration at 10 years of age in a two-dose schedule, although it can be started up to 17 years of age.
Between 26 and 45 years of age, vaccination should be evaluated on a case-by-case basis. The vaccine is 90% effective in preventing HPV infections, which cause carcinogenic lesions in the cervix.
However, vaccination does not eliminate the usefulness of screening by cervicovaginal cytology (pap smear) with HPV screening. Pap smears allow early detection of changes in the cervix, allowing cancer prevention before it actually starts.
Hepatitis B Virus and Liver Cancer
It is known that 80% of hepatocellular carcinomas (liver cancer) are related to Hepatitis B virus infection.
Since 1995, the PNV started to include the vaccine against the hepatitis B virus, reaching an annual coverage of 98%.
The first dose of this vaccine is given at birth. It is usually the baby’s first vaccine. This vaccination is followed by booster doses up to 6 months of age.
After the implementation of vaccination, a decrease in the incidence of liver cancer was observed, in some studies with a value greater than 90%, demonstrating the positive impact of vaccination.
The protection conferred by these vaccines is indirect: they do not attack cancer cells, but protect the body from infections that are precursors of these tumors and thus reduce their risk of emergence.
Hepatitis B and HPV vaccines are safe and are not associated with the onset of other diseases. The main adverse effect is pain and swelling at the bite site, which are transient and usually mild.
Get advice from your healthcare professional about vaccination, information is essential and adherence to vaccination by each of us is of crucial importance, since, along with a healthy lifestyle, are the interventions that depend on each individual to give more health to the years we are gaining by increasing life expectancy.
Vice-President of the Portuguese Association of General and Family Medicine