[Oncological principles of the treatment of facial skin cancer].

The complete mastery of reconstructive plastic surgery is a basic requirement essential for sufficient radical treatment of basal cell carcinoma in the facial area. Furthermore, the subclinical growth of the basal cell carcinoma must be taken into consideration. One can assume that the growth of the b.c.c. is much greater than the apparent clinical limits, especially in cases of recurrent tumours, tumours of long standing, tumours in frontal and temporal regions, as well as tumours with diameters of more than 2 cm and scleroderma growth. In such cases a safety margin of 8-15 mm is required, whereas in primary and locally well-defined b.c.c. a safety margin of 3-5 mm is regarded as sufficient. Following the examination of the microscopically controlled surgery developed by Mohs, which is suitable for improvement of the five-year cure rate after surgical treatment of b.c.c., the treatment of the squamous cell carcinoma of the bottom lip is dealt with. Taking into account the tendency of these tumours to metastasize, it is advised to carry out an elective neck-dissection confined to the suprahyoidal region in case of large squamous cell carcinoma and also in suspicious metastatic changes in the lymph nodes. The diagnosis of a malignant melanoma is fundamentally histological: The tumour is electrically excised with a clearance safety margin of surrounding skin of 0.5-1 cm if clinically there appears to be a 10% likelihood of the tumour being a malignant melanoma. If the histological frozen section of the excised tumour confirms the suspected diagnosis, in cases of high-risk melanomas an area of not less than 3 cm from the edge of the primary tumour must be reexcised. A free skin graft is preferred to cover the defect rather than a plastic repair by a pedicle-flap graft. The elective lymph node dissection in the case of malignant melanoma stage I is made dependent on the level of invasion and on the thickness of the tumour. Low-risk melanomas are operated on locally only whereas an elective dissection of the regional lymph nodes is generally recommended in cases of high-risk melanomas.