Mrs M was 70 years old and in good health. For two years she had been troubled by this cyst below her right eye. Her GP drained it twice but each time it returned, only to increase in size. On examination a solitary translucent cystic lesion was seen with some telangiectasia running over the surface. What is the diagnosis, management and differential diagnosis?
Diagnosis and management
Mrs M was referred to the dermatology unit for drainage and excision of the lesion, which was sent to the laboratory for histology to exclude alternative problems. An apocrine hidrocystoma was confirmed. Hidrocystomas are fairly common. They occur in adult life, equally in men and women. The eyes are most often affected.
Possible different diagnoses
- Cystic basal cell carcinoma.
- Blue naevus.
- Malignant melanoma.
Basal cell carcinoma
- Common in older patients who have suffered sun damage over the years.
- Occur on the face, trunk and limbs.
- May start as a small papule, with raised rolled edges that later breaks down, ulcerates or increases in size.
- Cystic lesions occur when the central area does not break down.
- Excision and biopsy preferred but alternative treatments are radiotherapy, curettage and cautery or cryotherapy.
Contributed by Dr Jean Watkins, a seasonal GP in Hampshire.