The Band That Widened
Ms. P., 56, books a full set before her son's wedding. On her left thumbnail she has a dark brown-to-black vertical band about 4 mm wide running from the cuticle to the free edge. The pigment spills a few millimeters onto the proximal nail fold, the band has widened since she first noticed it about nine months ago, and the plate is splitting within the band. She remembers no injury - no door, no hammer, no dropped object. No other nail is affected. She says her family doctor "looked at it last year and said not to worry." She wants a dark burgundy gel so it "won't show in the photos."
1. What should this finding make you think of, and what is your immediate professional obligation?
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A single, widening, irregular brown-black band with pigment on the proximal fold is subungual melanoma until a physician says otherwise.
The features that matter, using the standard nail-melanoma checkpoints: a brown/black band, in a single digit, that is changing, with extension of pigment onto the surrounding skin (Hutchinson's sign), plus nail splitting and no trauma history. Benign longitudinal streaks exist - a nail matrix nevus, a melanocyte activation from friction or medication - but a benign streak is usually uniform in color, narrow, and stable over years. This one has widened and now involves the fold.
Obligation: do not buff, thin, stain, or cover the nail. Refer promptly to a dermatologist or physician, in writing, with the specific reasons - the widening, the fold pigment, the splitting, the absence of injury. Tell the client exactly what you observed and that you are not diagnosing, but that this needs a medical look before any enhancement. Document the referral and the date.
2. The client says her doctor already cleared it and insists on a full set. Can you service the other nine nails?
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You may service the other nine nails if the client understands the situation and consents; you may not cover the affected nail.
A year-old "don't worry" is not the same as an evaluation of a band that has changed. A respectful way to handle it: "I'm not a doctor and I can't diagnose anything. What I can see is that the band has gotten wider and the pigment has moved onto the skin, and that's the kind of change a dermatologist should look at again - especially with photographs coming up. I'm happy to do the other nails today, but I won't put product over this one, because covering it means nobody can watch it."
Practical guardrails: no product, no buffing, no primer or dehydrator on that nail; do not take clinical photographs without written permission; note in the record that the service was limited and why, and that a medical referral was given. If the client refuses the referral and demands coverage, the correct answer is still no - declining a service is always within your authority, and "the client insisted" does not shift the risk to her.
3. Another tech insists the spot is just a bruise from a manicure last month. How do you reason about that without overstepping your scope?
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Compare the two pictures and let the timeline decide.
A subungual hematoma - a bruise under the plate - follows a specific injury, usually hurts at the time, and grows out with the nail: the leading edge moves distally, and because nail plate grows roughly 3 mm a month, a spot from an injury a month ago would still be near the base and traveling. It does not widen from the cuticle and it does not stain the surrounding fold.
This band starts at the matrix and has spread, which is the opposite pattern. Other look-alikes worth naming only so you know you cannot sort them out yourself: a benign matrix nevus (narrow, even, stable), fungal melanonychia, and bacterial green-black discoloration (which is green, soft, and associated with lifting).
The technician's job is description, not diagnosis: record color, width, borders, location, whether the fold is involved, and whether anything has changed since the last visit; then refer. A confident label - "it's just a bruise" - is the one thing that can cost a client months.