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Hair: hair samples should be plucked, not cut, from the patient and sent unfixed to the laboratory. The hair is mounted unfixed on glass slides and examined for hair shaft anomalies, or to look at the hair roots and count the telogen:anagen ratio - this requires a minimum of 50 hairs. Scanning electron microscopy provides more information in patients with hair shaft anomalies and picks up more subtle changes than those seen at light microscopy.

Nails: fragments of nails may be submitted for examination, either to detect fungi or the cause of nail pigmentation. The fragments are softened in phenol and then processed in the usual way for histology. For pigmented lesions or growths beneath the nail, the nail must be removed by the surgeon before skin biopsy of the nail bed is taken. Nails may be involved in several skin diseases, but usually a biopsy of skin involved elsewhere is taken to confirm the diagnosis.

Digits: pigmented lesions beneath nails often cause diagnostic problems in distinguishing between benign lesions, trauma and malignant melanoma. Trauma to the nail which bleeds grows outwards as the nail grows whereas naevi and melanomas do not. If melanoma is suspected the clinician must first remove the nail and biopsy the lesion on the nail bed. Excision biopsy is ideal but if this is not possible then a diagnostic biopsy is permitted. This is allowed in the nail bed as treatment for melanoma is amputation of the digit. Because of this the pathologist should only diagnose melanoma when there is a high degree of certainty, otherwise another biopsy is requested. Digits are measured and described in the usual manner, including which joints have been disarticulated. The tumour is measured and described. The surgical margin of excision is blocked and the tumour sampled through its deepest area.

Eyelid: the eyelid margins can be involved in a variety of benign and malignant tumours. Benign tumours are dealt with in the usual manner. In malignant tumours, especially basal cell carcinomas, squamous cell carcinomas and melanomas, the surgeon's aim is to remove all the tumour with as little normal tissue as possible. The surgeon may use a modified Mohs' technique to do this or orientate the specimen with pins and sutures. This will then be treated in the laboratory as a wedge excision and the margins carefully marked.

Ear: the ear may be involved in skin rashes, benign and malignant tumours. Skin rashes rarely only involve the ear and skin from elsewhere should be sampled. Benign lesions will have a variety of biopsy samples which are dealt with in the usual way. Tumours are often removed as a wedge and dealt with accordingly (Figure 37.6).

Lip: lip biopsies from benign lesions are treated as other biopsies but malignant tumours are removed as a wedge and dealt with accordingly (Figure 37.6).

Pilonidal sinus: occurs in the natal cleft of young-to-middle-aged males due to insinuation of hair shafts into the dermis and subcutis forming a tract variably lined by epidermis and/or granulation tissue. It is associated with serous discharge and, potentially, infection with pain and abscess formation. There may be several tracts present and communication points with the surface epidermis. Treatment involves wide elliptical excision of the skin and subcutis down to the level of the sacral fascia. The specimen is measured and the presence of opening(s)/tract(s) noted. A horizontal transverse block of the deep limit allows microscopic assessment of tract extension to the deep margin. The tract is demonstrated by serial vertical slices (Figure 37.8).

How To Prevent Skin Cancer

How To Prevent Skin Cancer

Complete Guide to Preventing Skin Cancer. We all know enough to fear the name, just as we do the words tumor and malignant. But apart from that, most of us know very little at all about cancer, especially skin cancer in itself. If I were to ask you to tell me about skin cancer right now, what would you say? Apart from the fact that its a cancer on the skin, that is.

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