Screening tests reveal the tumour mass, but its character remains unknown. A detailed examination of the pathology, determining the lesion type, will provide an answer helping to choose appropriate treatment options.
After screening tests, doctors may want to confirm or exclude cancer diagnosis with a biopsy. They will aspirate a small tissue sample with a needle or resect it during surgery, and then send it to the laboratory, where a qualified pathologist examines the lesion under a microscope.
What is the importance of precisely defining the type of lesion?
Knowing the type of tumour allows your healthcare professional to select the best treatment. Why? Let’s understand the basics of tumour pathology.
Neoplasm is an abnormal, uncontrolled, and excessive growth of the cells. Typically, the lesion does not stop growing, even if the triggers for that growth are no longer present.
The mass formed of these cells is called a tumour. However, some neoplasms, such as leukeamia and most in situ carcinomas, do not form a tumour.
Tumour masses may differ in their size and location in the body.
Characteristics of different types of neoplastic lesions
There are three types of tumours:
- Benign – they are non-cancerous neoplastic lesions. They do not spread to nearby tissues or other parts of the body. Most of them do not require treatment, unless they cause pain or other complications. Typically, when the doctor removes them, they will not return. But you should stay alert and observe them for possible changes or growth.
- Premalignant – these cells are not cancerous yet, but may become malignant. They are localized – do not invade nearby tissues. Usually, the doctors recommend removing them, just in case.
- Malignant – these cancerous tumours can grow, invade, destroy nearby tissues, and spread inside the body (metastasize). Unfortunately, at this stage doctors must apply aggressive treatments like surgery, chemo- or radiotherapy.
Sometimes, we cannot predict future tumour behaviour. For example, benign lesions may transform into premalignant and then into malignant ones. So, it is essential to schedule your checkups and stick to them.
What is the difference between a tumour and a cyst?
In scans, cysts may look similar to tumours and they may also form in any organ or tissue, but they can be easily distinguished from tumours.
The tumour is a solid mass of cells, while the cyst is defined as an encapsulated lesion containing air or fluid. On palpation, tumours feel firm, and cysts seem to be softer.
Benign and malignant tumours – differences
The tumour is not synonymous with cancer. Cancer is malignant, whereas tumours can also be benign and precancerous.
Benign tumor usually does not do much harm and do not affect other body parts. But, still, they may cause health problems when they press on nerves and blood vessels or trigger overproduction of hormones.
Below, we listed some examples of benign tumours:
- Adenomas develop in glandular epithelial tissue, a membrane covering glands, organs, and other structures. Their examples include colon polyps, fibroadenomas – a common benign breast tumour, and hepatic adenomas (in the liver). Initially, adenomas are not cancerous. However, some may transform into adenocarcinomas.
- Fibroids or fibromas grow in the fibrous or connective tissue. The most common example are uterine fibroids. Other types of this tumour include angiofibromas, which may appear on the face as small red bumps, and dermatofibromas on the skin. Some fibromas may cause health issues and require surgical removal. Some of these lesions transform into cancerous fibrosarcomas.
- Haemangiomas develop from blood vessels. They have a form of discoloured marks on the skin or are found in the body. We can observe them in newborns, but later they disappear. Usually, they do not require any special attention, unless they do not resolve spontaneously. Then, doctors treat them with laser surgery.
- Lipomas derive from fat cells. Usually, they affect people from 40 to 60 years old. Most are small, painless, soft, and movable. They include fibrolipomas, combining fat and fibrous connective tissue, and angiolipomas, appearing under the skin.
Premalignant lesions are not cancerous, but need your attention and regular monitoring.
Examples of premalignant lesions:
- Actinic keratosis (known as solar keratosis) has a form of crusty, scaly, and thick skin patches. Patients with pale skin are more prone to this condition. Sunbathing raises its risk. Sometimes it will transform into squamous cell carcinoma, so doctors recommend removing the actinic keratosis.
- Cervical dysplasia may occur in the cells lining the cervix in consequence of infection with human papillomavirus. Cells are not cancerous but may become malignant 10 to 30 years later, developing into cervical cancer. Usually, this condition can be diagnosed with a Pap smear test. Treatment methods include freezing or removing the affected tissue.
- Lung metaplasia occurs in the bronchi, tubular ducts that carry air to the lungs. In some cases, especially in smokers, glandular cells lining the bronchi may be transform into squamous cells or cancer.
- Leukoplakia is a painless condition associated with thick white patches with raised edges developing in the mouth. They require doctors’ attention if they do not resolve with time. The doctor can remove them with a laser or scalpel. If possible, patient should preferably quit smoking.
Malignant lesions are cancerous. This type of tumour develops when cells divide uncontrollably. If they continue to grow and spread, the disease may become life-threatening.
Cancerous lesions differ, depending on the type of cells from which they originate:
- Carcinomas form from epithelial cells found in the skin and tissues lining organs. They are common malignant tumours and may develop in the stomach, the prostate, the pancreas, the lung, the liver, the colon, or the breast.
- Sarcomas originate in connective tissue such as cartilage, bones, fat, and nerves. They develop in the cells outside the bone marrow. Most are malignant.
- Germ cell tumours affect cells producing sperm and eggs. Usually, they locate in the ovaries or testicles, but sometimes doctors find them in the chest, the brain, or the abdomen.
- Blastomas derive from embryonic or developing cells. They are often diagnosed in children, and may affect the brain, eyes, or the nervous system.
- Meningiomas are the most common brain tumours. Sometimes they require surgery or other treatment.
How does identifying the type of lesion influence treatment?
Benign tumours do not affect your health, but doctors sometimes recommend removing them, to prevent possible development of cancer. Unfortunately, they are also easier to overlook.
Precancerous tumours are more likely to become cancerous, so they require surgical treatment. In many cases, tumour removal prevents cancer. However, the risk is still higher than in people without pre cancerous changes.
If the lesion is malignant, you may need a surgery first. Malignant tumours require aggressive treatments with potent anticancer agents such as chemotherapeutic drugs, radiation, and biological drugs. But, at the early stages, available therapies can effectively treat malignant tumor.
To wrap up
There are three main types of neoplastic changes: benign, precancerous, and malignant. Benign and precancerous lesions do not require treatment, but removing precancerous tumours prevents cancer. On the other hand, malignant tumours are cancers and they require surgery and aggressive treatments.