Keloids and Hypertrophic Scars in Cancer Patients' Surgical Journeys
For cancer survivors, surgical scars often symbolize triumph over disease. But for some, these marks transform into raised, painful, and expanding lesions known as keloids or hypertrophic scars. These pathological scars affect 4.5%-16% of African, Hispanic, and Asian populations, compared to <0.1% of Europeans, creating disparities in surgical recovery experiences 4 6 .
Keloids and hypertrophic scars originate from dysregulated wound healing involving three phases: inflammation, proliferation, and remodeling. When this process derails:
Keloids show a 20-fold collagen increase versus normal skin, while hypertrophic scars show a 3-fold rise 5 .
| Feature | Keloids | Hypertrophic Scars |
|---|---|---|
| Growth pattern | Extends beyond wound borders | Confined to original wound |
| Regression over time | Rare | Common (after 6–12 months) |
| Collagen type | Predominantly Type I (thick fibers) | More Type III (finer fibers) |
| Recurrence after excision | >50% | <10% |
| Common sites | Earlobes, chest, shoulders | Joints, extensor surfaces |
Keloids and cancers share fibrotic microenvironments and biological drivers:
Aberrant DNA methylation and microRNA (e.g., miR-29 downregulation) occur in keloids and metastatic melanoma 9 .
A landmark 2021 study in Scientific Reports analyzed Taiwan's National Health Insurance Research Database (NHIRD) 8 :
17,401 keloid patients (1998–2010) vs. 69,604 matched controls (1:4 ratio).
Prior cancer diagnoses to ensure temporality.
Controlled for age, sex, geography, and comorbidities.
Used logistic regression and Cox proportional hazard models.
| Cancer Type | Relative Risk (RR) | High-Risk Subgroup |
|---|---|---|
| All cancers | 1.49 | Both genders |
| Skin cancer | 1.73 | Males (RR=2.16) |
| Pancreatic cancer | 2.19 | Females |
| Esophageal cancer | 1.70 | Both genders |
Keloid fibroblasts and melanoma cells both show reduced miR-29, enhancing collagen deposition and tumor growth.
Chronic inflammation in keloids and pancreatitis drive fibrosis via shared IL/TGF-β pathways.
Use Z-plasties or fascial sutures in high-tension areas (joints, chest) 1 .
Deprodone propionate plaster or fludroxycortide tape quell early inflammation 1 .
| Therapy | Mechanism | Efficacy Notes |
|---|---|---|
| Intralesional triamcinolone | Suppresses collagen synthesis | 50–80% response; +5-FU improves results 4 9 |
| Cryotherapy | Freezes tissue, inducing apoptosis | 50–75% flattening; hypopigmentation risk 4 |
| Radiation therapy | Post-excision fibroblast inhibition | Recurrence <10% with 12–20 Gy 1 |
| 5-Fluorouracil (5-FU) | Antimetabolite targeting fibroblasts | 60–90% improvement combined with steroids 9 |
| Stem cell therapy | Paracrine modulation of inflammation | Experimental; reduces myofibroblasts 4 |
| Reagent/Technique | Function | Application Example |
|---|---|---|
| TGF-β1 inhibitors | Block fibroblast activation | Tested in pirfenidone trials (NCT02823236) 4 9 |
| miR-29 mimics | Restore anti-fibrotic microRNA | Reversed collagen overproduction in keloid fibroblasts 9 |
| 3D keloid cultures | Simulate extracellular matrix | Drug screening (e.g., verapamil efficacy) 4 |
| Optical coherence tomography (OCT) | Real-time collagen imaging | Guided excision in Mohs surgery 7 |
| Circulating tumor DNA (ctDNA) | Detect micrometastases | Post-surgical monitoring in high-risk patients 8 |
Keloids and hypertrophic scars represent more than cosmetic concerns—they are windows into systemic dysregulation linking fibrosis, inflammation, and cancer. For oncology teams, adopting tension-reducing surgical techniques and early anti-inflammatory interventions (e.g., silicone sheets, steroid tape) can significantly improve scarring outcomes 1 2 . Meanwhile, patients with keloids benefit from vigilant cancer screening, particularly for skin and pancreatic malignancies. As research unravels shared pathways like TGF-β and miR-29, therapies that once treated scars may one day prevent cancers, transforming remnants of disease into symbols of resilience.
"Keloids teach us that healing is not always linear—but science can bend the curve toward recovery."