A growing scar can be worrying, but a keloid is a benign skin growth, meaning it is not cancer. Understanding keloid cancer risk requires separating ordinary keloid behaviour from a suspicious new skin change—and from studies about cancer diagnoses in people who have keloids. [1,2]
Keloids are benign and are not normally expected to turn into cancer. Rare case reports describe cancers arising in keloid scars, while some cancers can mimic them. A persistent sore, repeated bleeding, or an unusual new change needs assessment. Studies linking keloids with cancer do not prove that keloids transform into cancer. [1–4]
What Does “Cancer-Like” Mean in Keloid Research?
Keloids grow beyond the original injury because scar tissue production becomes excessive. They can itch, hurt, and return after treatment. These keloid symptoms can be distressing without being cancerous. [1,3]
The review of keloid pathobiology by Tan and colleagues examines keloids from a “quasi-neoplastic” perspective. In plain language, this means they share some growth-related features with tumours, including changes in cell activity, inflammation, and tissue-growth signals. [1]
However, keloids are non-malignant. Local growth into nearby skin is different from malignant spread to distant organs. Researchers study these similarities to understand keloid formation and explore possible treatments—not to establish that a typical keloid is progressing towards cancer. [1]
A paper’s use of words such as “tumour”, “invasive”, or “cancer-like” needs to be read in that context.
What Does the Keloid Cancer Risk Study Actually Show?
The population-based study by Lu and colleagues compared 17,401 people diagnosed with keloids with 69,604 controls using Taiwanese health-insurance records. Its time-ordered analysis found an association with non-melanoma skin cancer and a pancreatic cancer association among women. These findings concern diagnoses in groups of patients, not proof that cancer developed inside their keloids. [2]
Association Is Different From Transformation
A person can have both a keloid and an unrelated cancer. A database association cannot establish that the keloid caused the cancer, that scar cells became cancer cells, or that removing the scar would prevent cancer.
The study lacked information about keloid location, extent, and severity, as well as lifestyle and family history. Most participants were ethnically Chinese, limiting generalisation. Its initial analysis did not establish which diagnosis came first; later analyses excluded cancers diagnosed before keloids, and some findings changed. [2]
These limitations matter when interpreting research about keloid cancer risk.
Does Having Keloids Mean You Need Extra Cancer Screening?
Lu and colleagues proposed additional skin checks and pancreatic screening for women with keloids. This was a recommendation from an observational study, not evidence that screening improves outcomes. [2]
The US Preventive Services Task Force recommends against pancreatic cancer screening in asymptomatic adults who are not known to be at high inherited or familial risk. [5]
A keloid alone does not establish a need for pancreatic scans or tumour-marker blood tests. Discuss screening with your usual clinician, based on your overall medical and family history. Assessment of a changing skin lesion is a separate matter from screening someone without symptoms.
How Should Rare Reports of Cancer in Keloid Scars Be Understood?
The American Academy of Dermatology’s keloid overview states that keloids do not turn into cancer. This reflects the usual clinical understanding of a keloid as a benign condition. [3]
The medical literature also contains rare reports of cancer arising in tissue described as a keloid. For example, a case report by Majumder and colleagues described squamous cell carcinoma, a type of skin cancer, arising in a postsurgical keloid scar. [4]
These reports justify examining unusual changes. They do not establish a reliable transformation rate or mean that ordinary keloids commonly become malignant. A case report describes an individual event; it cannot tell you the probability for everyone with the condition.
Cancer developing within scarred skin, cancer initially mistaken for a keloid, and a separate cancer in someone with keloids are different situations. Keeping them separate prevents an unusual report from becoming an exaggerated claim about all keloids. [1,2,4]
Keloid vs Skin Cancer: What Needs Checking?
Appearance alone is not always enough to distinguish a keloid from another skin growth. Some benign and malignant tumours can resemble keloids. [1]
| Finding or situation | What it does—and does not—tell you |
|---|---|
| A diagnosed keloid slowly extends beyond the wound | This can be ordinary keloid behaviour; growth alone does not establish cancer. |
| Itching or tenderness | These can occur in benign keloids and are not cancer tests. |
| A sore remains open or repeatedly bleeds | This needs assessment; injury, infection, and cancer are among possible explanations. |
| A scar-like lump has an uncertain diagnosis | Further investigation may be needed before scar treatment begins. |
These distinctions are supported by the keloid review and guidance on suspicious scar changes and diagnosis. [1,6,7]
Arrange a prompt appointment for persistent ulceration, repeated unexplained bleeding, or an unusual change in an established scar. An ulcer is an area where the skin has broken down into a sore. Do not assume it is harmless because the area was previously labelled a keloid. [4,6]
If your concern is a scar getting bigger, note changes in its surface and symptoms as well as its size. Photographs can help you describe those changes during an appointment.
Is Marjolin Ulcer Risk the Same as Keloid Cancer Risk?
No. A Marjolin ulcer is cancer arising in a scar or chronic wound, most commonly an old burn scar. It is usually squamous cell carcinoma. This is a distinct clinical problem, not another name for a growing keloid. [6]
According to DermNet’s guidance on Marjolin ulcer, warning features include a persistent non-healing sore that may bleed easily, become painful, or enlarge. Such changes require examination and may need a biopsy. [6]
Evidence from longstanding burn scars, pressure sores, or chronic ulcers cannot automatically be used to calculate risk in an intact keloid. A percentage reported for burn scars should not be presented as the chance that your keloid will become cancerous.
Likewise, routine post-burn keloid treatment should not replace assessment of an unexplained open sore within a burn scar.
When Is a Biopsy for Keloids Needed?
A typical keloid can often be diagnosed by examination. A biopsy may be appropriate when the clinician suspects another condition or cannot confidently explain a change. [7]
The American Academy of Dermatology’s diagnosis guidance explains that a skin biopsy involves numbing the area and removing a small tissue sample for examination under a microscope. This can help distinguish scar tissue from other causes of a lump or ulcer. [7]
Being offered a biopsy does not mean cancer has been diagnosed. It means tissue examination may answer a question that appearance alone cannot resolve.
Tell the clinician about your tendency to form keloids and ask about wound care after sampling. The need for an accurate diagnosis should guide the decision, with scar planning discussed alongside it.
Once the diagnosis is confirmed, keloid scar treatment can focus on appropriate goals such as reducing raised tissue and relieving symptoms. These treatments should not be presented as cancer prevention.
Practical Patient Checklist
Before your appointment:
- Confirm whether the growth has been examined and diagnosed as a keloid.
- Bring photographs showing changes in its surface or shape.
- Report persistent sores, repeated bleeding, or changes you cannot explain.
- Share previous treatments, including injections, surgery, or radiotherapy.
- Ask what a biopsy would clarify if one is recommended.
- Discuss cancer screening according to your personal and family history, rather than a research headline alone.
Conclusion
Keloid cancer risk should be understood in context: keloids are benign, research associations do not prove transformation, and rare case reports do not establish a common risk. Uncertain diagnoses and persistent changes still deserve assessment. [1–4]
Book a consultation if you want your scar assessed or its treatment options explained. Seek prompt medical assessment for a persistent open sore, repeated unexplained bleeding, or an unusual change in an established scar.
Read Also / See Related
- Keloid vs hypertrophic scar — Understand the differences between two types of raised scars.
- Do scars get bigger with age? — Explore changes in scar size and visibility over time.
- Newly formed keloid scars — Learn about assessment and management of an emerging raised scar.
Sources
- [1] Tan S., Khumalo N., Bayat A. — 2019 — Understanding Keloid Pathobiology From a Quasi-Neoplastic Perspective: Less of a Scar and More of a Chronic Inflammatory Disease With Cancer-Like Tendencies. Frontiers in Immunology, 10, 1810. Uploaded PDF reviewed. DOI: 10.3389/fimmu.2019.01810.
- [2] Lu Y.Y., Tu H.P., Wu C.H., et al. — 2021 — Risk of Cancer Development in Patients With Keloids. Scientific Reports, 11, 9390. Uploaded PDF reviewed. DOI: 10.1038/s41598-021-88789-1.
- [3] American Academy of Dermatology — Keloid scars: Overview. Patient information about keloids.
- [4] Majumder A., Srivastava S., Ranjan P. — 2019; published online 2018 — Squamous cell carcinoma arising in a keloid scar. Medical Journal Armed Forces India, 75(2), 222–224. Case report. Article.
- [5] US Preventive Services Task Force — 2019 — Pancreatic Cancer: Screening. Final recommendation statement.
- [6] Junaid F.; editor Oakley A. — 2017 — Marjolin ulcer. DermNet. Clinical features and diagnosis.
- [7] American Academy of Dermatology — Keloid scars: Diagnosis and treatment. Diagnosis, biopsy, and treatment guidance.
Medical disclaimer
The information in this article is provided for general educational purposes and does not replace professional medical advice, diagnosis, or treatment. Consult a dermatologist or another qualified healthcare professional about your symptoms and treatment options. Do not disregard professional medical advice or delay seeking care because of information you have read on KeloidCare.org. Responses to keloid treatments vary, and individual results cannot be guaranteed.