1. Seborrhoeic wart
Also known as seborrhoeic keratosis or basal cell papilloma.
Benign epidermal tumours of unknown cause. Common in the elderly. They are
commonest on the trunk but also affect the face and limbs. Patients may have one,
several, or hundreds. Treatment is only required if the seborrhoeic wart is traumatized,
when it may become inflamed or bleed, sometimes simulating a melanoma.
What should I look for?
• A well-defined oval, pigmented tumour, around 0.5–2cm in diameter, that appears stuck
onto the surface of the skin.
• Rough surface that may feel slightly greasy. Dark pits studded over the surface—easier
to see with magnification using dermoscopy.
• Colour can range from a pale pink-brown to dark brown or black.
• Seborrhoeic warts may be virtually flat or raised by several mm.
Chondrodermatitis nodularis helicis chronica
Nodules caused by prolonged pressure on the skin of the ear, but sun damage or cold may
also play a part. The history is usually characteristic and differentiates this nodule from a
skin cancer. The affected ear is generally the one on which the patient sleeps, and pain
prevents from lying on that side. Apparently, nuns who wore wimples were affected by
chondrodermatitis. Treatments include relieving pressure, topical or intralesional
corticosteroids, cryotherapy and, surgery.
What should I look for?
• A tender nodule on the helix or, in women, the antihelix of the ear.
• A keratotic plug or a small ulcer in the centre of the nodule.
2. Dermatofibroma
Also known as fibrous histiocytoma or sclerosing haemangioma.
The localized proliferation of fibroblasts is probably triggered by minor trauma such as
an insect bite. These benign growths are common in young women. If you can make a
confident diagnosis, no treatment is required—excision will merely leave another scar.
Multiple dermatofibromas have been reported in conditions such as HIV infection, SLE,
and other diseases in which the immune state is altered.
What should I look for?
• A brownish red dermal nodule, 0.5–1cm in diameter, usually on the arm, shoulder,
thigh, or leg.
• The overlying epidermis is usually smooth.
• The lesion is firm—this suggests the diagnosis.
• A central scar seen under dermoscopy with pseudo-pigmentation peripherally.
• Pinch the skin gently on each side of the tumour, and it will sink down into the
dermis—the ‘buttonhole sign’ or ‘dimple sign’.
Pyogenic granuloma
Typically, this vascular tumour presents at the site of a penetrating injury, e.g. rose thorn,
usually on the fingers, lips, or face.
• An amelanotic malignant melanoma or SCC may look like a pyogenic
granuloma—always ask the patient if anything preceded the development of the tumour.
Was there a ‘mole’ at the site, or did it arise on normal skin? Always send excised lesions
for histological examination.
What should I look for?
• A history of rapid growth: pyogenic granulomas grow on previously normal skin over a
period of weeks to a size of 0.5–4cm.
• Fleshy vascular tumour composed of friable granulation tissue that bleeds readily on
contact.
• Exclude any underlying pigmented lesion: inspectany ‘pyogenic granuloma’ at an
atypical site particularly carefully, using a dermatoscope, if possible. Melanin can be
mistaken for old haemorrhage.
Other common benign tumours or inflammatory nodules
Epidermal :
• Viral infections ,e.g. viral wart or molluscum contagiosum.
• Nodular prurigo (caused by chronic rubbing).
• Epidermal naevus (warty lesion,present since infancy).
Dermal :
• Epidermoid cyst or ‘sebaceous’ cyst: although not sebaceous at all, but arises from the
upper part of the hair follicle. has a punctum. Often becomes inflamed and ruptures.
• Pilar cyst: arises from the lower part of the follicle and usually found in the scalp—no
punctum. Spontaneous rupture uncommon.
• Keloid: dense fibrous scar tissue spreading beyond the original wound.
• Spider naevus; Campbell de Morgan spot (cherry angioma).
• Infantile haemangioma (strawberry naevus).
• Neurofibroma.
• Xanthelasma or xanthoma.
