Thyroid-Related Eye Disease

(Canada—Canadian Family Physician, April 1998, pp. 749, 757.) Thyroid-related eye disease most commonly occurs in cases of Graves' disease, but the eye may also be involved in other forms of hyperthyroidism or hypothyroidism or may be affected in patients who are clinically and chemically euthyroid. The condition is believed to be caused by the action of cross-reacting antibodies on orbital fibroblasts or related muscle tissue. Most patients have only mild symptoms, such as irritation in both eyes and cosmetic concerns. Conversely, severe cases of thyroid-related eye disease may result in double vision or even loss of vision. Treatment may range from use of lubricants to steroid therapy and surgical decompression. Systemic steroid therapy may benefit patients with thyroid-related optic neuropathy. In addition to orbital decompression, irradiation may be helpful in certain patients. The mnemonic “NO SPECS” is endorsed by specialist organizations to remind physicians of key aspects of thyroid-related eye disease: no signs or symptoms; only signs (lid retraction or lid lag), but no symptoms; soft tissue involvement (lid edema or conjunctival chemosis); proptosis; extraocular muscle involvement; corneal involvement, and sight loss.

Identifying Malignant Melanoma

(Great Britain—The Practitioner, April 1998, p. 254.) The number of new cases of malignant melanoma diagnosed each year worldwide is estimated to be 7.8 per 100,000 men and 12.3 per 100,000 women, and this incidence is increasing. Malignant melanoma is one of the most common malignancies in young adults and the second most frequently occurring neoplasm (after cervical carcinoma) in women 20 to 35 years of age. Risk factors for malignant melanoma include freckles, multiple small benign moles (more than 20), atypical nevi and a history of severe sunburn, especially in childhood. The most common sites of malignant melanoma are the back in men and the lower leg in women. Lesions most frequently present as a mole that itches, bleeds or changes in size, shape or color. Use of a checklist of three major and four minor clinical features can improve diagnostic accuracy. Melanoma is likely if a new mole arises or an existing mole enlarges, or if lesions change in shape or color, especially if a variety of shades are seen in a single lesion. The minor features (diameter greater than 6 mm, inflammation, itching and oozing, crusting or bleeding) add to the probability of melanoma.

Premalignant Skin Conditions

(Great Britain—The Practitioner, April 1998, p. 270.) Most cases of squamous cell carcinoma of the skin are preceded by one of several premalignant conditions. These conditions vary greatly in their potential for malignant transformation and in the rapidity of progression to carcinoma. Actinic keratoses have a low potential for conversion to malignancy and have a latent period of probably at least 10 years. However, since patients may have large areas of skin affected by actinic keratoses, the cumulative risk for malignant transformation is significant. Cutaneous horns also have a low potential for malignancy, but such lesions represent dysplastic epidermis and should be removed and sent for pathologic diagnosis. In contrast, Bowen's disease is carcinoma in situ and has a potential for metastasis of approximately 10 percent. The scaly, erythematous plaque of Bowen's disease may be difficult to differentiate from several other skin lesions and perhaps may be diagnosed only by biopsy. Keratocanthoma is also regarded as premalignant. In some cases the tumor regresses spontaneously, but some clinicians recomend wide excision.

Polycystic Ovary Syndrome

(Great Britain—The Practitioner, February 1998, p. 98.) The original description of polycystic ovary syndrome, comprising anovulation, obesity, hirsutism, infertility and enlarged ovaries, has been extended to include hyperinsulinemia, type 2 (non–insulin-dependent) diabetes mellitus and abnormal lipid profiles. The condition is estimated to occur in 3 percent of women and in more than one half of those with menstrual dysfunction. Pelvic ultrasonography, including transvaginal evaluation, is the most important diagnostic modality in polycystic ovary syndrome, but other tests and laboratory investigations may be useful to rule out alternative diagnoses in individual patients. The goal of treatment of polycystic ovary syndrome is to control symptoms and minimize the adverse effects of obesity and abnormalities of insulin and lipid metabolism. Selected oral contraceptive agents are useful to restore normal menstrual cycles. Some women also require treatment for hirsutism, acne, obesity and infertility. In cases of infertility when anovulation is confirmed and the patient is not hypogonadotrophic or hypoestrogenic, clomiphene is usually the first-line therapy to induce ovulation.