Acanthosis Nigricans
In this condition there is hyperpigmentation and hyperkeratotic thickening of the skin in the flexures, and small papillomatous lesions that may also appear on mucous membranes of the mouth, particularly if associated with malignancy. These changes are often related to benign conditions, such as obesity and hyperinsulinaemia, or are induced by drugs, such as steroids. However, if they develop suddenly in middle age, particularly in the absence of obesity, it may indicate underlying malignancy (particularly of the stomach or bowel). These tumours can be aggressive.
Acquired ichthyosis
This condition is characterised by areas of rough, scaly dry skin. There may be areas of hyperkeratosis on palms and soles. In many, this is a congenital problem inherited through an autosomal dominant gene, with symptoms usually starting in the first year of life and continuing into old age.
However, first appearance of such symptoms in adults is usually associated with an underlying problem, such as thyroid disease, or is related to drugs, such as cimetidine. Also consider underlying malignancy. Successful treatment of any underlying problem should improve the ichthyosis.
Inflammatory breast cancer
In this type of breast cancer malignant cells infiltrate the skin and lymphatics causing inflamed, hot and oedematous skin with a patch of reddened, swollen skin that mimics the skin of an orange (peau d'orange). It is easily mistaken for infective cellulitis, and if axillary or cervical lymph nodes are enlarged it is possible that infection could be diagnosed.
Usually there is no palpable lump in the breast itself. This type of breast cancer is more common in older women; referral to a breast clinic is recommended if it does not respond to antibiotics and/or is not improving after a week.
Paget's disease of the nipple
This condition presents with unilateral, apparent eczematous change or ulceration of one nipple and the areola, which is associated with an underlying intraductal or infiltrating carcinoma. The lesion is sharply demarcated and may itch, ooze and bleed. Eventually the nipple is destroyed. The condition usually develops in women aged 50 to 60 years and progresses slowly. Diagnosis should be confirmed by biopsy; a mammogram is required to determine the underlying problem, which may or may not be palpable manually. Referral to a breast clinic is necessary.
Extra-mammary Paget's disease
Similar eczematous changes occasionally occur around the genitalia, affecting the vulva or perianal area, glans penis or genitoscrotal area. This is a rare cutaneous adenocarcinoma, usually starting in the epidermis, but often associated with underlying adnexal carcinoma and internal malignancy.
Perianal Paget's disease is associated with a GI malignancy, while in men there is more likely to be a genitourinary carcinoma. The diagnosis is confirmed by biopsy and wide excision of the area is recommended.
Horner's syndrome
The symptoms of Horner's syndrome develop as the result of involvement of the sympathetic nerve in the neck or brain stem. The patient may have certain specific signs, such as unilateral ptosis, miosis of the pupil or enophthalmos on the affected side with loss of sweating on that side of the face.
A number of different neurological problems, as well as dissection of the carotid artery, can lead to these changes but a carcinoma at the apex, upper lobe of the lung can also be the cause. Chest X-ray is required to exclude this.
Skin secondaries
These may present before there is diagnosis of a primary carcinoma or as in this case of a woman who had undergone a mastectomy for breast cancer years before. Firm, rubbery, skin-coloured/brown/bluish black nodules develop in the skin. Here the nodules had developed in the lie of the scar and were clearly related to the old malignancy.
Where there is no previous history, a thorough search for the primary carcinoma should be made. A clue to its site may come from biopsy of the lesion. Secondaries in breast cancer most commonly occur on the chest, scalp and neck.
Dermatomyositis
Symptoms of this condition include a marked heliotrope rash on sun-exposed areas, such as the face and limbs, including the palms where there is also erythema, thickening and scaling. Other signs include erythema and splinter haemorrhages at the base and sides of the nail plate. Associated myopathy affects the proximal muscles of the limbs.
The cause is unknown but there may be underlying malignancy which should be identified because prognosis can be poor. Other causes include genetic factors and viral infections; treatment involves oral corticosteroids.
