When a Tender Spot on Your Skin Won't Heal

Why a sore that won't heal is worth a look

Skin heals on a schedule. A scrape, a shaving nick, or a popped pimple usually closes within one to two weeks. A spot that scabs, seems to heal, then reopens — or that simply persists past a month without closing — has broken that pattern, and persistence is the signal that matters. The two most common skin cancers, basal cell and squamous cell carcinoma, classically show up as exactly this: a sore that will not finish healing.

The common thread is sun. Ultraviolet radiation from the sun, sunlamps, and tanning beds is the main modifiable cause of skin cancer 1Ref 1National Cancer Institute (PDQ Screening and Prevention Editorial Board) (2025).Skin Cancer Prevention (PDQ®)–Health Professional Version.Ultraviolet radiation from the sun, sunlamps, and tanning beds is the main modifiable risk factor for skin cancer.. Non-healing lesions tend to appear where a lifetime of that exposure lands — the face, ears, scalp, lips, and the backs of the hands and forearms. A spot in one of those places that keeps not healing earns a closer look, not because it is certainly serious, but because this is the way serious things here tend to begin.

The everyday explanations, and why a checklist can't settle it

Most spots that are slow to heal are not cancer. An inflamed hair follicle, a cyst, a stubborn insect bite, or irritant contact dermatitis — barrier damage from repeated contact with water, soap, friction, or chemicals — can all linger, feel tender, and look angry for weeks 2Ref 2Patel K, Nixon R (2022).Irritant Contact Dermatitis — a Review.Irritant contact dermatitis results from non-immune skin-barrier damage caused by repeated contact with water, soap, friction, or chemicals, and can persist and feel tender.. Rough, scaly patches called actinic keratoses sit in a gray zone of their own: sun-damaged spots that are not yet cancer but can turn into squamous cell carcinoma over time, which is why clinicians often treat them, most commonly by freezing them with liquid nitrogen 3Ref 3American Family Physician (2007).Treatment Options for Actinic Keratoses.Actinic keratoses are precancerous scaly lesions that can progress to squamous cell carcinoma and are most commonly treated with lesion-directed cryotherapy (liquid nitrogen)..

Here is the hard part. None of these can be reliably told apart from an early skin cancer by eye. A dermatologist cannot do it from a photograph, and a symptom list on a screen cannot do it either. That is not a reason to panic — it is the reason the honest answer to a persistent spot is always the same: have it examined in person rather than watched indefinitely at home.

What 'won't heal' actually means

A practical threshold is four to six weeks. Ordinary wounds close well within that window, so a spot that is still open, crusting, or reopening after a month has crossed a line worth acting on. So has one that heals over and then returns in the same place more than once. A spot that heals then comes back can be especially misleading, because a skin cancer can crust over and look resolved between episodes, buying itself weeks while it is still there.

The single most useful thing you can tell a clinician is how long the spot has been there and that it has not healed. Duration and non-healing are what separate a spot worth sampling from a fresh scab. A sore that keeps returning to one fixed location is a stronger signal than one that migrates or clears completely.

The features clinicians weigh

When a clinician examines a non-healing spot, no single feature confirms or rules out cancer; they read the whole picture. The findings that raise concern are consistent ones, and knowing them helps you describe what you are seeing:

• Bleeds too easily — oozes or bleeds with minor contact, or bleeds on its own
• A raised, rolled, or pearly border, sometimes with tiny visible blood vessels across the surface
• A central dip, crater, or crust that keeps reforming after it flakes off
• A change in sensation — newly tender, itchy, numb, or tingling
• Steady growth — wider, thicker, or more raised than it was a month ago
• Color that does not belong — a pearly translucence, or a dark brown-to-black area within the spot

These are patterns, not proof. A harmless spot can show one of them, and an early cancer can show none. That is exactly why the list points toward an exam, not toward a self-diagnosis.

Photograph it and track it before your visit

Before the appointment, document the spot. Take a clear, well-lit photo from directly above, place a ruler or a coin beside it for scale, and note the date. Re-photograph every couple of weeks from the same distance. This turns 'it seems bigger' into a record a clinician can actually measure, and it captures change that is too slow to notice day to day.

Some of these spots are easy to overlook. A scalp lesion hides under hair and gets found only by a partner or a hairdresser. Skin cancer on the ear is written off as weather-chapping, and a non-healing spot on sun-exposed hands is mistaken for a scrape that just will not quit. If a skin growth that keeps getting bigger is somewhere you cannot see well, having someone photograph it for you is worth the awkwardness.

What the appointment and biopsy involve

The visit itself is usually quick. A clinician examines the spot, often with a handheld magnifier called a dermatoscope, and if anything looks suspicious, takes a skin biopsy — a small sample removed under local anesthetic and sent to a pathologist. Looking at the cells under a microscope is the only way to know what a spot is; nothing before that step is a diagnosis. For a dark or pigmented non-healing spot that could be melanoma, guidelines favor removing the whole lesion with a narrow margin rather than sampling a fragment, so its depth can be measured accurately 4Ref 4Swetter SM, Tsao H, Bichakjian CK, et al. (2019).Guidelines of care for the management of primary cutaneous melanoma.For a suspected melanoma, guidelines favor excisional or narrow-margin biopsy that removes the whole lesion so tumor depth can be measured accurately..

If the biopsy shows a basal or squamous cell carcinoma, most are removed by a straightforward surgical excision, and low-risk tumors need only a standard margin of normal skin taken around them 5Ref 5Kim JYS, Kozlow JH, Mittal B, et al. (2018).Guidelines of care for the management of cutaneous squamous cell carcinoma.Low-risk cutaneous squamous cell carcinomas are treated with standard surgical excision margins, while high-risk tumors are managed with Mohs micrographic surgery.. Tumors in high-risk spots — the face, ears, lips, and hands — or with aggressive features under the microscope are often handled with Mohs surgery, a technique that checks the margins during the procedure so the smallest necessary amount of tissue is removed 5Ref 5Kim JYS, Kozlow JH, Mittal B, et al. (2018).Guidelines of care for the management of cutaneous squamous cell carcinoma.Low-risk cutaneous squamous cell carcinomas are treated with standard surgical excision margins, while high-risk tumors are managed with Mohs micrographic surgery.6Ref 6Ad Hoc Task Force (Connolly SM, Baker DR, Coldiron BM, et al.) (2012).AAD/ACMS/ASDSA/ASMS 2012 appropriate use criteria for Mohs micrographic surgery.Mohs micrographic surgery is appropriate for skin cancers in high-risk anatomic locations, such as the face and ears, and for tumors with aggressive histology..

How soon should it be seen?

This is not an emergency, but it is not something to watch for another season either. A spot that has not healed in a month is a weeks-not-months appointment. Move faster than that if the spot bleeds without being touched, is growing visibly week to week, or is a new dark or black spot that will not heal — and faster still if it sits on the lip, ear, or eyelid, where even small tumors matter more.

Two groups should lower their threshold further. People who have had a skin cancer before are at higher risk of another, and people who are immunosuppressed — organ-transplant recipients and those on immune-suppressing medication — develop skin cancers more often and sometimes faster. For them, a non-healing spot is worth a call sooner rather than later.