Most squamous and basal cell carcinomas may be adequately treated by complete eradication either by excision or by destructive means, such as curretage, freezing or electrodesiccation. Excision has the advantage of providing for histological analysis to ensure negative margins, although the alternative modalities of local destruction have proven to be highly effective (Fitzpatrick et al., 1999), especially when lesions are small and biologically nonaggressive. In situations where tumours are present in close proximity to vital structures, particularly involving facial skin, a modified Mohs technique may be desirable (Leslie and Greenway, 1991). In this setting, multiple frozen sections of marginal tissue are examined at the time of the excision. Lymph node dissection in the case of invasive squamous cell carcinoma may be indicated when there exists suspicious clinical enlargement of draining lymph node chains.
The role of wide excision and lymph node dissection in the setting of vertical growth phase melanoma is potentially problematic. Primary lesions are generally recommended to be excised with a margin that will minimize the likelihood of local recurrence. However, this recommendation is controversial, with some experts arguing that although wider excisions may decrease the incidence of local metastases, they fail to improve survival. This assumption is based on the contention that local metastases of melanoma generally correlate with contemporaneous seeding of distant sites (Ackerman and Scheiner, 1983). In recent years, sentinel lymph node sampling has gained acceptance in the treatment of many vertical growth phase melanomas. In this procedure, a radiographically detectable dye is injected at the site of the primary tumour. This dye is taken up by draining lymphatic vessels and delivered physiologically to regional lymph nodes. The first nodes to be detected by this method are presumed to be candidates for early metastases, and therefore they are surgically removed and studied extensively by histological and sometimes by immunohistochemical analysis for the presence of occult melanoma metastases. Occasionally, entire lymph node chains will be removed as part of a procedure termed prophylactic elective regional lymph node dissection. The clinical rationale for such procedures is to eradicate surgically early metastases while they are theoretically confined to draining lymph nodes. This approach remains to be validated by prospective data. Moreover, it is complicated by the theoretical possibility that latent systemic metastases may occur synchronously with nodal ones, and by the notion that nodal deposits of tumour cells may in some instances eventuate in positive effects in terms of sensitizing the immune system against specific tumour-associated antigens.
In this regard, adjuvant therapy for melanoma has recently focused on immunoenhancing therapies, such as melanoma vaccines and treatment with proinflammatory mediators, such as interferon-a. Although these approaches have provided encouraging preliminary data in the treatment of clinically advanced melanoma metastases (Murphy et al., 1993), their role as adjuvants to ameliorate the potential for eventual metastatic spread is not as yet fully defined and awaits further experimental validation.
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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.