Body site of cutaneous malignant melanoma : Primary tumor location in relation to phenotypic and prognostic factors

The main purpose of this thesis was to analyze the primary body site of cutaneous malignant melanoma (CMM) in relation to phenotypic traits and prognosis. It is clear that several characteristics of CMM are different, and vary with the skin location where the tumor originated. The different types of sun exposure (chronic/occupational and/or intermittent/recreational) on different parts of the skin could be one of the reasons for this. A new computer program, EssDoll©, developed for detailed studies of site of CMM was used in this thesis. A cohort of 756 patients, with head-neck CMM was analyzed. The CMM density was 3.4 times higher in the face compared to skin surfaces outside the head-neck area. Similarly, nodular melanoma (NM) was 2.3- and lentigo maligna melanoma (LMM) 74 times more dense in the face. It is known that chronic exposure to UV-fadiation is a risk factor for LMM, and our findings suggest such a relationship for NM as well. 'Me mean age at diagnosis was 12 years higher for CMM in the head-neck compared to sites outside the head-neck (66 vs. 54 yr.). Ibis relatively later diagnose supports the view of a natural tan to be somewhat protective for CMM. We found tumor thickness to be the only statistically significant prognostic factor for patients with head-neck CMM. The surgical resection margin at operation of the primary tumor (1-10 vs. 2: 11 mm) had no impact on patient outcome. A software, EssDoll©, was developed and used in a cohort of 2517 patients with 2608 primary CMMs. The primary sites of CMMs was plotted on a movable doll and linked to patient ID. With this software one or more skin area(s) can be chosen for analysis. Using this type of analysis we confirmed that the predominant site for CMM in men was the trunk, and in women the lower extremities. Superficial spreading melanoma (SSM) and NM were most common on the trunk while LMM was most common in the head-neck. Patients with hereditary CMM (HCMM) and patients who have been treated for a sporadic CMM have an increased risk to develop new CMM. The anatomic sites of CMM in these patient groups were analyzed separately. in the database there were 104 patients with HCMM and 69 patients with more than one sporadic CMM (MCMM). For patients with sporadic MCMM, the second tumor often arose in the same body field as the first. The concordance was statistically significant (p