Learn about the main tests used to diagnose cancer

Early detection of a tumor depends on many factors and remains essential to increase the chances of curing the disease and improving the prognosis. Early diagnosis allows for less invasive and less aggressive treatments for the patient," explains oncologist Maria Alzira Rocha, a member of the Scientific Committee of the Vencer o Câncer Institute.

The main type of test that helps diagnose cancer is screening, as pointed out by Dr. Fernanda Cano Casarotto, a member of the screening and prevention committee of the Brazilian Society of Clinical Oncology: "Important for diagnosing cancers at earlier stages, screening tests are a public health strategy, aimed at the general population, that is, people without symptoms."

The goal, in this case, is to detect premalignant lesions. Diagnostic tests are indicated in cases of suspected cancer, for people who already have symptoms or are at higher risk of developing the disease. Below are the main cancer screening, investigation, and diagnosis tests:

Mammography

It is the primary test for early detection of breast cancer, as it can detect tumors and microcalcifications, indicating a suspected cancer. It should be performed annually starting at age 40, with or without symptoms of the disease, according to the recommendations of medical societies and institutions. Women with a family history of the disease or who carry the BRCA1 and BRCA2 genes should begin screening earlier, under medical supervision.

Colonoscopy

It's the main screening test for colorectal cancer (or bowel cancer) and should be performed starting at age 45. It visualizes the inside of the rectum and large intestine with the help of a flexible camera device inserted into the patient's anus. In addition to detecting lesions that may be cancerous, colonoscopy also allows for the removal of polyps (benign lesions that can become cancerous) found in the intestine.

PSA (Prostate Specific Antigen)

One of the main prostate cancer screening tests, performed through a blood test, can detect early signs of the disease and should be performed starting at age 50. However, it is a starting point for a more in-depth investigation of suspected cancer. "In addition to the PSA test, an annual evaluation with a urologist for a digital rectal exam is recommended starting at age 50. To confirm the diagnosis (if suspected), prostate MRI and biopsy can also be performed," adds oncologist Maria Alzira Rocha.

Pap smear

It's the most common gynecological exam and one of the most important in preventing cervical cancer. It detects early cellular changes that may indicate infections, sexually transmitted diseases, and especially cancer. According to the Ministry of Health, it should be performed annually from the age of 25.

HPV DNA Research

Since May of this year, the Brazilian Unified Health System (SUS) announced the gradual replacement of the Pap smear with the HPV DNA test. The test is performed in the same manner as the Pap smear, except that, instead of looking for changes that could indicate precancerous lesions or cancer, the HPV DNA test directly detects the presence of the HPV virus. "Directly detecting HPV allows for more accurate diagnoses, so it's important for people to be aware of this test and ask their doctor about it," explains Fernanda Casarotto.

Computed Tomography

A computed tomography scan is an imaging test that uses radiation to provide detailed images of body structures. In the context of cancer, the test can identify small nodules and tumors of different types, making it essential not only for early diagnosis but also for monitoring the disease and defining treatments.

Dermatological consultation

A skin evaluation by a dermatologist is recommended for skin cancer screening, especially for people with frequent sun exposure or a family history of skin cancer. "Furthermore, during the skin evaluation, it's possible to remove high-risk, pre-malignant lesions, or even melanoma itself," adds the specialist from the Vencer o Câncer Institute.

Ultrasound, x-ray and blood test

Imaging and clinical tests such as ultrasound, x-rays, and blood tests can be used to aid in the diagnosis of cancer, but a biopsy is still necessary to confirm the diagnosis.

Biopsy

A biopsy is the primary test used to diagnose cancer. "It's like cancer's birth certificate, giving the disease's first and last name, the final diagnosis," adds Casarotto. It involves removing a tissue sample from the body for laboratory analysis. It's usually performed after a screening test indicates a suspected cancer.

Tumor markers

These are proteins that can be altered in cases of cancer. They are typically used to monitor the stage of cancer, but they do not determine diagnoses. "In practice, we see many people anxious and even scheduling appointments with oncologists when an abnormal test result appears, but markers alone are not powerful enough to diagnose cancer," explains Maria Rocha.