10 derm mistakes you don’t want to make
Patient care can suffer—or be delayed—by these common mistakes. Here’s how to avoid them.
When I have a report from a general pathologist suggesting a potentially worrisome lesion (melanoma, severely dysplastic nevus, [atypical] Spitz nevus), I always suggest to my patients that we get a dermatopathologic second opinion. (I send all my dermatopathology specimens to dermatopathologists, so this applies to patients referred in with prior pathology in hand.)
Sometimes, even the dermatopathologists do not agree on the nature of the lesion. In such cases, I have my “MELTUMP discussion” with patients. That is, I tell patients that we don’t know for sure what it is, and that ultimately only the final lab test—time—will tell us the true nature of the lesion (FIGURE 3).4
- Send all “skin” to a dermatopathologist. You owe it to your patients.
- Send pictures (electronic or hard copy) to the dermatopathologist when the pathology report and clinical picture do not appear to match. While pictures of skin lesions and dermoscopic photographs would most likely be meaningless to general pathologists, they are useful to dermatopathologists. Research has shown that pathologists in various areas of medicine may alter their diagnosis or differential diagnosis when presented with additional clinical information.5
Mistake #5: Freezing neoplasms without a definitive Dx
“We’ll freeze it and if it doesn’t go away, then…”
This approach poses a significant risk to you (medicolegally) and your patient.
While most of the time what I see has been inappropriately frozen first by first-line providers, that is not always the case. Dermatologists also fall into this trap. FIGURE 6 shows a lesion just behind the hairline on the frontoparietal scalp that was frozen by a very good, and reputable, dermatologist. The patient came to me for a second opinion with an “obvious” BCC.
Some clinicians are “thrown off” when a lesion (like the one on this patient) has hair. Some sources6 indicate that BCCs never have hair, but this is patently untrue.
FIGURE 6
This shouldn’t have been frozen
A dermatologist froze this lesion on a patient’s scalp, believing that it was seborrheic keratosis, based on the patient’s history. The patient sought a second opinion, and the lesion (which had hair) was histologically identified as basal cell carcinoma.
- Don’t freeze a lesion when you are unsure; biopsy it. This is especially critical when you consider that cryotherapy is not considered a first-line treatment for BCC, the most common human malignancy. It is better to biopsy, assure the diagnosis, and then provide the appropriate therapy.
Mistake #6: Treating psoriasis with systemic corticosteroids
Plaque psoriasis can, albeit uncommonly, be transformed to pustular psoriasis after the administration of oral or injectable systemic corticosteroids.7 Although this rarely occurs, most experts consider this poor practice and not worth the risk. In addition, some experts note that systemic glucocorticoids are a drug trigger for inducing or exacerbating psoriasis.8
- Avoid systemic corticosteroids in psoriasis, since psoriasis is generally a long-term disease and systemic corticosteroids are a short-term fix. if there is widespread psoriasis and you are not familiar with systemic treatments, refer the patient. If there is localized disease, consider topical treatment options—such as various strengths of corticosteroids, calcipotriene, and tazarotene (individually or in combination)—depending on location and plaque thickness.
Mistake #7: Doing shave biopsies on melanocytic lesions
For a melanoma, not only can shaving part way through the vertical dimension of the lesion interfere with staging, it can also hinder the pathologist’s ability to arrive at the correct diagnosis.9
- Do a full-thickness, narrow-margin, fully excisional biopsy when you suspect melanoma. Certainly, there are individuals who are expert at saucerization (deep shave biopsies, often with scalloped, sloping edges that go to the deep reticular dermis) and who can perform biopsies of melanocytic lesions while still obtaining reasonable pathologic staging information.
Mistake #8: Using corticosteroid/antifungal combination products
Corticosteroid/antifungal combination products are generally shunned by dermatologists, although they are used extensively by nondermatologists.9 The difficulty with a preparation like Lotrisone, which contains a class III corticosteroid (betamethasone dipropionate [Diprosone]) and the antifungal clotrimazole, is that it is often used long-term for presumed fungal infection on thin-skinned areas. Unfortunately, though, chronic use in these areas can lead to atrophy and striae (FIGURE 7).
Additionally, corticosteroid is essentially “fungus food.” Majocchi’s granulomas can form because the corticosteroid interferes with clotrimazole’s antifungal effect. Note also that these combination products can suppress fungus sufficiently to render cultures and KOH preparations falsely negative and alter the clinical appearance of psoriasiform dermatitis, interfering with subsequent, accurate diagnosis.
FIGURE 7
Striae after corticosteroid combination therapy
This patient developed striae and atrophy after using a combination high-potency topical corticosteroid/antifungal preparation in a thin-skinned area (proximal medial thigh). It was unclear what the prescriber was treating.
