As you may know, cancer is a condition where cells begin to divide or grow uncontrollably, destroying healthy tissue. But you might be wondering, what is precancerous?
The term “precancerous” describes a condition that might or is likely to become cancer1. In recent decades, researchers have identified different molecular or cellular changes that can help pinpoint early damage to healthy tissue before it becomes cancer.
Understanding the changes that occur at the cellular (microscopic) level will increase your awareness and help you become more proactive about your health. With early detection and timely intervention, many precancerous conditions can be treated, stalled, or even reversed.
Here, you’ll gain insight into precancerous changes, various precancerous conditions, and the difference between benign, precancerous, and malignant (cancerous) cells. You’ll also learn about the power of early detection and specific actions you can take to stay on top of your health.
What Is Precancerous at the Cellular Level?
Cells are always growing, ageing, and dying. We have about 200 different types of cells that make up our body2. These normal cells go through their life cycles with a highly regulated process that allows healthy cooperation between adjacent cells. Once a cell is damaged or is too old to function properly, it undergoes apoptosis, or a controlled cell death3. The neighbouring cell begins to proliferate to replace the missing cell.
During proliferation, the DNA of the cell is duplicated to give two identical cells4. However, sometimes the replication machinery makes errors. The newly formed DNA carries mutations that can be permanent if not repaired5. Some of these abnormal cells can be precancerous cells.
When a mutation occurs in a gene coding for the shape, the cell will end up misshapen6. If the mutation occurred in genes coding for pigmentation, the cell displays an unusual colour7.
Interestingly, these abnormal cells escape their controlled death and continue proliferating8. Ultimately, they will form noticeable entities like misshapen and discoloured moles or small polyps in the cervix and the colon, for example.
Here are some of the most common general features and explanations regarding precancerous cell changes.
What Are Atypical Cells?
“Atypical” is a term used to describe cells that look different from normal cells under a microscope9. Atypical cells can be found in various tissues and organs. Their presence can indicate potential precancerous changes, although not all atypical cells progress to cancer.
“Hyperplasia” refers to tissue that grows thicker10. Most of the time, this is a normal thing our bodies do. For example, part of a woman's uterus gets thicker every month, and that's because of hyperplasia.
Hyperplasia can sometimes increase the risk of developing cancer. For example, endometrial hyperplasia caused by an imbalance of estrogen and progesterone hormones in a woman's body is not a precancerous condition. However, it increases a woman’s risk for developing endometrial cancer in the future11.
Another example is atypical ductal hyperplasia (ADH), a fairly common lesion found in about 3.5-5 per cent of breast biopsies12. While ADH isn’t cancer, women with ADH have an increased risk of developing breast cancer in the future13.
Atypical lobular hyperplasia (ALH) is a condition where cells inside the breast's milk-producing glands (lobules) appear abnormal under a microscope. According to the NHS, it can also increase your risk of developing breast cancer in the future14.
While there’s no way to know how long it might take for atypical cells to turn into cancer, your healthcare provider will want to keep a closer eye on your symptoms and increase the frequency of cancer screening.
What Is Precancerous Dysplasia?
Dysplasia is a condition where cells in the body grow abnormally15. The severity of dysplasia can vary from mild to severe16. Mild or low-grade dysplasia means only a small number of cells are abnormal. Moderate dysplasia means a greater number of cells are abnormal. Severe (high-grade) dysplasia means that most or all of the cells are abnormal.
Carcinoma in situ is the most severe form of dysplasia. It means that the entire thickness of the epithelial layer (the tissue that lines your organs) contains abnormal cells, but not yet invaded deeper tissues17.
Dysplasia can occur in different body parts, including the lobules (milk-producing glands) of the breasts, cervix, colon, oesophagus, skin, and oral cavity. Colonic dysplasia can be detected during a colonoscopy18. Regular cancer screenings, such as mammograms, can help find precancerous growths and abnormalities like dysplasia before they become cancerous19.
What Is a Precancerous Skin Lesion?
In the context of skin cancer, precancerous conditions refer to abnormal skin cells or lesions that have the potential to become cancerous but are not yet malignant. Recognising and treating these lesions can help prevent skin cancer.
Some common precancerous skin conditions include:
Actinic Keratosis (AK): This is the most common precancerous skin condition20. It manifests as rough, scaly patches that can be red, pink, or flesh-colored. They typically develop on sun-exposed areas, such as the face, ears, neck, scalp, backs of the hands, and forearms. If untreated, AK can progress to squamous cell carcinoma, a cancer type.
Moles (Atypical or Dysplastic Nevi): While most moles are benign, some might be considered "atypical" or "dysplastic," meaning they have certain characteristics that are different from common moles21. Atypical moles might have irregular borders, varied colours, or a larger size. People with many atypical moles are at an increased risk for melanoma, which is the most dangerous form of skin cancer22. It's essential to monitor these moles and have them checked by a dermatologist.
Bowen's Disease: This condition (also called squamous cell carcinoma in situ) is considered an early form of squamous cell carcinoma23. It appears as red, scaly patches and, like AK, often develops on sun-exposed areas.
Leukoplakia: This condition manifests as thick, white patches on the mucous membranes, which can sometimes be inside the mouth24. While leukoplakia itself is not a skin cancer, it can sometimes be associated with squamous cell carcinoma25.
What Is Precancerous vs. Benign?
Precancerous lesions are abnormal cells that pose a greater risk for becoming cancerous. Precancerous cells have not spread to other parts of the body, but they have the ability to do so if they continue to grow unchecked. Active surveillance (monitoring for changes) and early cancer treatment are key to stopping disease progression.
Benign skin lesions are not cancerous26. If the cells remain benign, they will not become invasive cancer (spread to nearby tissues or other body parts). Many benign tumours do not need treatment, especially if they aren’t causing symptoms. However, if a benign tumour requires treatment, it’s usually removed surgically.
For instance, a benign brain tumour can still be dangerous and may be removed if it puts pressure on structures, nerves, and blood vessels. In rare instances, benign tumours can undergo microscopic changes and become cancerous27.
Common benign lesions include28:
- Seborrheic keratoses: The most common benign epithelial tumour is generally harmless but may be removed for cosmetic reasons.
- Skin tags: These non-cancerous lumps or bumps often appear in areas where the skin rubs against clothing or skin, such as the neck, armpits, and groin.
- Cherry angiomas: These are small, bright red bumps on the skin that are usually harmless. An overgrowth of blood vessels causes them and can appear anywhere on the body.
- Lipomas: These are the most common subcutaneous soft-tissue tumours made up of fat cells that can develop anywhere. Lipomas typically feel soft and rubbery to the touch and are usually painless.
Will My Precancerous Cells Turn Into Cancer?
Let’s say during a routine check-up, your doctor told you they found precancerous lesions or carcinoma in situ, the earliest form of cancer. Anxiety most certainly heightens at the terms “cancer” and “carcinoma.” It’s completely understandable.
But, in this case, the term “precancer” does not mean you have cancer. It does mean that you need to be on the lookout for any changes. For skin cancer, you should thoroughly check your skin to make sure you’re aware of how it normally looks29.
Very few abnormal cells will turn into cancer cells, and nobody can tell for sure if these lesions will change over time. Actually, most will stay benign all your life. Even if the abnormal cells become malignant, the good news is that thanks to regular check-ups, cancer can be detected at a very early stage, and, if it’s detected, treatment options exist. And they work.
How Long Does It Take for Precancer to Become Malignant (Cancerous)?
Since precancerous (or abnormal) cells haven't turned into cancer, you have a window of opportunity to intervene. You can do this either by monitoring the condition more closely or by proactively removing the precancerous cells.
If treated or managed appropriately, many precancerous conditions never progress to cancer. However, if left unchecked, some precancerous cells can become malignant over time30. The speed of this progression can vary widely depending on the type of precancerous condition and individual factors.
Annual screenings and physical exams promote early detection and help your health professional or oncologist address and manage both benign and precancerous conditions before they progress or cause other health complications.
What Is Precancerous Screening?
Precancerous screening, often just called "cancer screening," involves tests and examinations to detect precancerous conditions or early-stage cancers before they produce symptoms31. The primary goal is to identify and manage these early changes, thereby reducing the risk of progression to full-blown cancer.
Routine screenings include:
Mammography: X-rays of your breasts help detect early-stage breast cancer. However, it can also identify precancerous conditions, like ductal carcinoma in situ (DCIS) or atypical ductal hyperplasia (ADH)32.
Cervical Screening: This is a test where cells from the cervix are collected and examined under a microscope33. It detects some precancerous changes (like cervical dysplasia) and early-stage cervical cancer.
HPV Test: Done at the same time as the cervical screening, this test checks for high-risk strains of human papillomavirus (HPV) that are linked to cervical cancer34.
Colonoscopy: This procedure allows a physician to examine the inner lining of the large intestine (colon and rectum)35. It can detect precancerous polyps and early-stage colorectal cancer36.
Faecal Occult Blood Test (FOBT) or Faecal Immunochemical Test (FIT): These tests check for tiny amounts of blood in the stool, which can be an early sign of colorectal cancer or large polyps37.
Skin Examinations: Regular skin checks, either self-examinations or by a dermatologist, can identify precancerous lesions like actinic keratosis or early-stage skin cancers38.
Vigilance Is Key for Keeping Cancer at Bay
Even though cellular changes are not cancerous, they are a warning sign. From atypical hyperplasia in the breasts to dysplasia in the cervix, the body sometimes provides early alerts of irregularities that demand our attention. To heed these signals and detect abnormalities, it’s worth having the standard cancer screenings mentioned above.
Ezra invites you to know your risk factors with a quick five-minute assessment. You can also follow up by booking an MRI Scan with Spine, which is a complement to the above standard screening tests. It covers 14 other organs, making it a more comprehensive screening. This method is not only effective but it’s also safe, pain-free, and reasonably priced.
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References
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