We spoke to Francesco Cognetti, an oncologist and lecturer in Medical Oncology at UniCamillus University.
A total of 44,000 patients were diagnosed with lung cancer in Italy in 2023 (30,000 men and 14,000 women), while more than 35,000 people died of this disease in 2022 (data from AIRTUM – Italian Association of Cancer Registries). Around 80% of cases are caused by the non-small cell lung cancer variant.
As far as global figures are concerned, the World Health Organisation (WHO) points out that in 2022 around 1.81 million people died worldwide of lung cancer, with 2.48 million new cases being reported.
It is therefore the most common type of neoplasm and the leading cause of oncological death.
However, this data is relatively recent: at the beginning of the 19th century it was an extremely rare disease, affecting only 1-2% of the population. It began to spread in the middle of the 20th century and became the leading cause of death, especially among men, the most common assumption being that exposure to toxic gases during the First World War was the main cause. In the 1950s, however, it became clear that there was such a strong correlation between cigarette smoking and the onset of symptoms that anti-smoking campaigns were launched worldwide.
A diagnosis of lung cancer may sound like a death sentence, but there is some good news: the overall 5-year survival rate for lung cancer patients has increased by 15% in recent years. However, we continue to emphasise that early diagnosis of lung cancer increases the chances of survival, from 7-10% 5-year survival for advanced stage diagnosis to 60-70% for early stage diagnosis.
For this reason, the position paper ‘Tumore al Polmone: la Via Maestra è la Diagnosi Precoce’ (in English: Lung cancer: the right way is early diagnosis) was presented at the Chamber of Deputies in Rome on 27th September by a panel of representatives from the scientific community, patient associations and institutions, and was supported by Johnson&Johnson MedTech.
The talk highlighted the importance of early diagnosis, especially in high-risk groups such as smokers over the age of 50. To achieve this goal, free screening programmes and smoking cessation courses should be offered.
Types of lung cancer
There are several types of lung cancer, the most common of which is non-small cell lung cancer (NSCLC). This group has three main subtypes: adenocarcinoma, which often affects non-smokers and is the most common type; squamous cell carcinoma, which is typical of smokers and develops mainly in the central airways; and large cell carcinoma, a rarer form that can grow in any part of the lung.
However, about 20% of cases are small cell lung cancer (SCLC), which is characterised by extremely rapid and aggressive growth.
The main risk factor for lung cancer is undoubtedly cigarette smoking. “In smokers, the risk is 23 times higher than in non-smokers and 11 times higher than in former smokers”, says Francesco Cognetti, oncologist and lecturer in Medical Oncology at UniCamillus University. “The risk increases with the number of cigarettes smoked: it is 3 times higher for those who smoke less than 5 cigarettes a day and 36 times higher for those who smoke more than 25”. The age at which people stopped smoking is also very important: the risk decreases with the number of years since they stopped smoking.
Although cigarette smoking is responsible for 80% of lung cancer cases, it is not the only cause.
Other risk factors include exposure to radioactive gases such as radon, asbestos, environmental pollution and genetics.
The types of cancer that affect smokers are different from those that affect non-smokers: squamous cell carcinoma and small cell carcinoma, which are extremely aggressive, are more common in smokers, while in non-smokers, adenocarcinoma, which grows more slowly and affects more peripheral areas of the lung, is more often diagnosed.
mRNA vaccines: a promising prospect
What therapies are available? “Treatments are very different depending on the type of cancer”, explains Cognetti. 20% of cancers are oncogene addicted, i.e. they are not related to smoking, but have molecular alterations that may favour the development of the disease. They can be treated with molecularly targeted drugs, which are very useful both in patients at a late stage and in those who have already undergone surgery.
For cancers caused by cigarette smoking, chemotherapy is generally combined with immunotherapy, which has come a long way since its introduction. As mortality remains high, we are looking for new strategies, which could be offered by vaccines.
Already used in the prevention of hepatocellular carcinoma, vaccines are nothing new in cancer treatment. This is the era of mRNA vaccines, building on the experience of Covid-19, which involved the production of vaccines containing a viral protein and the development of mRNA vaccines is being tested in both lung cancer and malignant melanoma”, explains Cognetti.
Unlike Covid vaccines, cancer vaccines are curative, not preventive. Their aim is to stimulate the immune system to recognise and attack cancer cells. The process begins with an analysis of the tumour in which researchers identify specific proteins, called antigens, that are present only on cancer cells or in significantly higher amounts than on healthy cells. Once these antigens have been identified, a vaccine containing mRNA—a molecule that tells the body’s cells how to produce these tumour proteins―is developed. When the vaccine is administered, the mRNA enters the cells, which start producing the tumour proteins. At this point, the immune system recognises these proteins as foreign and activates T-lymphocytes, which are essential in the fight against cancer cells. These T-lymphocytes multiply and become capable of recognising and destroying cancer cells in the body.
The key aspect of this approach is that once the immune system has been ‘trained’ to recognise cancer cells, it can remain vigilant and ready to fight any relapses over time: this makes mRNA vaccines a major hope in the fight against cancer.
“Immunotherapy has been tested in melanoma with moderate success: very important results have been achieved even in the most advanced stages. Now the time has come for lung cancer”, explains Cognetti. “There is an ongoing trial that has shown significant results in a few dozen patients and has therefore been extended to 130 lung cancer patients, involving 34 treatment centres in the UK, the United States, Poland, Hungary, Germany, Spain and Turkey. The results are starting to come in and they look very promising”.
The trial is called LuCa-MERIT-1 and aims to stimulate the patient’s immune system against non-small cell lung cancer by giving the body’s cells instructions to produce cancer-specific proteins.
“It is not yet a standard treatment, but in the not too distant future, mRNA vaccines may be introduced in the fight against lung cancer”, Cognetti concludes.