Cancer: Symptoms, Diagnosis and Treatments

Cancer is caused by the uncontrolled proliferation of abnormal or altered cells, which can lead to the formation of tumors. What are the most dangerous and common cancers? What are the first symptoms of cancer? How to prevent cancer?

1. What are the most dangerous cancers?

According to the World Health Organization (WHO), cancer is the second leading cause of death worldwide, killing around 10 million people every year. According to the institution, in 2020, the most dangerous cancers and therefore, likely to lead to death, were:

- Lung cancer, responsible for 1.80 million deaths;

- Colorectal cancer, causing 935,000 deaths;

- Liver cancer, causing the death of 830,000 people;

- Stomach cancer, leading to the death of 769,000 individuals;

- Breast cancer, caused 685,000 deaths.

• The most common cancers

The most common cancers are not necessarily the most dangerous. In 2020, the WHO identified several pathologies according to the number of cases:

- Breast cancer, the most common in women;

- Lung cancer, which is also the most deadly;

- Colon cancer  ;

- Prostate cancer, the most common in men, but which can be treated well;

- Non-melanoma skin cancer;

- Stomach cancer.

• Cancer symptoms

The warning signs of cancer vary, from one disease to another. Cancer can progress insidiously for years, without causing symptoms. Nevertheless, certain clinical signs should alert, as they may suggest the appearance of cancer, such as:

• Persistent and unjustified pain;
• Rapid and unexplained weight loss;
• Chronic and intense fatigue;
• Digestive problems (nausea, vomiting, diarrhea, constipation, loss of appetite, etc.);
• Urinary disorders;
• Unusual bleeding: in the stool, urine, oral or vaginal secretions (outside the menstrual cycle or menopause);
• Physical changes: lymph node edema, a change in the appearance or color of a mole, the appearance of a palpable lump or mass, night sweats, etc. ;
• An inability to heal.

• Causes of cancer

The precise causes of cancers are difficult to establish. Cancer is often the consequence of the association of several risk factors, which are divided into two categories: external factors and internal factors.

- External factors

External factors include risk behaviors for developing certain cancers. In fact, about a third of cancer deaths are linked to five main elements, which increase the chances of developing a disease. The first risky behavior in the occurrence of cancer is smoking. Lung cancer is main cancer caused by smoking. However, epidemiological studies reveal that 17 other cancers are associated with smoking, such as cancer of the larynx, pharynx, mouth, pancreas, kidney, stomach, etc. An unhealthy or unbalanced diet is also one of the causes of cancer. Diet plays a major role in the prevention of this disease. Alcohol consumption is also associated with cancer, as it is believed to be responsible for approximately 150,000 cases of cancer per year and 15,000 deaths each year. Overweight, obesity, and lack of physical activity are other risk factors for developing cancer. It is also essential to protect yourself from UV radiation, whether natural or artificial because it can cause skin cancer.

There is also an infectious risk, as viral infections (caused by viruses or bacteria) are linked to almost 20% of cancers worldwide. Exposure to electromagnetic waves, certain chemical substances, and air pollution, is also associated with cancer risks.

- Internal factors

Internal factors are inevitable. For example, the older a person gets, the higher their chances of contracting cancer. Other elements may also be involved, such as genetic and hereditary factors, hormones, chronic inflammatory or autoimmune diseases.

2. Cancer: when to consult?

As soon as an unusual or persistent symptom appears, it is essential to consult a doctor as soon as possible. In the case of cancer, the diagnosis of which is confirmed by a medical examination, the general practitioner refers the patient to an oncologist. When a person already has the symptoms of cancer, this means that the disease is established. It is therefore important to listen to the signals sent by the body. Indeed, the earlier the treatment, the higher the chances of recovery and the less heavy the treatments. This is why screening campaigns are carried out when possible, such as for breast cancer ., prostate or cervix. This makes it possible to identify anomalies that can develop into cancer, to identify and better treat the disease. Other screenings are carried out, such as for colorectal cancer, oral or skin cancers.

• Cancer tests and diagnosis

When cancer is suspected following a clinical examination carried out by the doctor or a screening, different examinations are proposed, depending on the location of the tumor. Generally, a blood test is prescribed in order to assess the general state of health of the patient and to look for the possible presence of blood markers, revealing the existence of cancerous cells.

Then, an appointment for a medical imaging examination must be made, such as X-ray, CT scan, MRI (Magnetic Resonance Imaging), endoscopy, or even scintigraphy. It can also be a biopsy (removal of cells from the suspected tumor) or genetic or molecular analysis of the tissues.

Screening is also one of the ways to discover precancerous or cancerous cells, especially when the disease has not yet manifested itself. This is the case of mammography (to detect breast cancer) or cervical biopsy (for cancer of the cervix).

• Cancer treatments

Some types of cancers have high cure rates, especially if diagnosed early and correctly. Cancer treatment is increasingly personalized and management is multidisciplinary. Each type of cancer requires a specific protocol, which is most often based on a combination of radiotherapy, chemotherapy, and/or surgery. Depending on the objective of the patient, who wishes to improve his quality of life or extend his life expectancy, the treatment may vary.

On the other hand, the psychological dimension is taken into account, as well as physical and psychosocial well-being.

When a patient is in the terminal phase of cancer, palliative care is offered to him, not to cure him, but to relieve him. Palliative care aims to treat the symptoms of cancer and to maintain or improve the comfort of the patient's life.

3. How to prevent cancer?

It is possible to reduce the risk of cancer by adopting the right behaviors, such as:

• Have a healthy and balanced diet (avoid industrial dishes or refined sugars);
• Avoid smoking;
• Practicing physical activity and sports;
• Maintain a healthy weight;
• Limit consumption of alcohol and medication;
• Get vaccinated (against the papillomavirus or hepatitis B );
• Respect good practices for sun exposure, protect yourself against the sun and avoid artificial UV rays;
• Get screened regularly, for cancers for which it is possible.