We have previously demonstrated the use of pyrosequencing to investigate NRAS [neuroblastoma RAS viral (v-ras) oncogene homolog] mutations in melanoma biopsies. Here, we expanded the analysis to include BRAF (V-raf murine sarcoma viral oncogene homolog B1), another member of the Ras-Raf-mitogen-activated protein kinase (MAPK) signalling pathway, and analysed a total of 294 melanoma tumours from 219 patients. Mutations in BRAF exons 11 and 15 were identified in 156 (53%) tumours and NRAS exon 2 mutations in 86 (29%) tumours. Overall, mutations in NRAS or BRAF were found in 242 of 294 tumours (82%) and were found to be mutually exclusive in all but two cases (0.7%). Multiple metastases were analysed in 57 of the cases and mutations were identical in all except three, indicating that BRAF and NRAS mutations occur before metastasis. Association with preexisting nevi was significantly higher in BRAF mutated tumours (P=0.014). In addition, tumours with BRAF mutations showed a significantly more frequent moderate to pronounced infiltration of lymphocytes (P=0.013). NRAS mutations were associated with a significantly higher Clark level of invasion (P=0.022) than BRAF mutations. Age at diagnosis was significantly higher in tumours with NRAS mutations than in those with BRAF mutations (P=0.019). NRAS and BRAF mutations, however, did not influence the overall survival from time of diagnosis (P=0.7). In conclusion, the separate genotypes were associated with differences in several key clinical and pathological parameters, indicating differences in the biology of melanoma tumours with different proto-oncogene mutations.

No abstract

The present investigation demonstrates that CDKN2A germline gene mutations were observed in 7.8% of the 64 Swedish melanoma kindreds that each included at least two first-degree relatives with melanoma and dysplastic nevus syndrome. No CDKN2A exon 1beta or CDKN2B mutations were identified. The critical genes responsible for the inheritance of a susceptibility to develop melanoma among family members in this population have yet to be identified.

No abstract

No abstract

Objectives/Hypothesis: For cutaneous malignant melanoma (CMM) of the head and neck, neither prognostic factors in population-based groups, nor outcome with respect to surgical resection margins is clear. Therefore, we analyzed data in a regional registry to align treatment results for CMM of the head and neck with prognosis and survival times. Study Design: Patient material collected prospectively for an 18-year period in a Swedish cancer registry underwent statistical analyses to establish the most reliable prognostic factors and the influence of surgical treatment on the survival of patients with CMM of the head and neck. Methods: Data originated from the CMM database of the Stockholm-Gotland area of Sweden. Tumor thickness or invasiveness (Breslow or Clark's levels), extent of surgical margin, sex, histogenetic type, anatomic site, and ulceration were compared statistically for 469 patients. Results: Male patients with head and neck CMM had a 68% 10-year survival rate; the 10-year survival rate for female patients was 87%. The corresponding figures for CMM at other sites were 83% and 90%, respectively. Tumor thickness (or Clark level of invasion) was the only statistically significant prognostic factor in a multivariate analysis (P < .001). The surgical resection margin seemed to be of no importance to outcome. Conclusions: Long-term survival after treatment for CMM of the head and neck is better than reported in most earlier publications, presumably because our evaluation used population-based materials, an important factor in accurate reporting of this kind. Tumor thickness is the main prognostic factor in estimating outcome.

Background. Thin melanomas can metastasize and be lethal. The predictive importance of tumor thickness in thin melanomas and the specific features identifying the patients at risk have not been investigated fully. Methods. Prognostic factors were analyzed in 585 patients with clinical Stage I invasive cutaneous malignant melanoma with a thickness of less than or equal to 0.8 mm. The patients were included in a population‐based cancer registry in Stockholm county during 1976–1987. They constituted about 64% of all patients with thin melanomas who were diagnosed in the region during the study period. Information was available on age, sex, anatomic site of the tumor, histologic type of melanoma, level of invasion, tumor thickness, and tumor regression. In a Cox regression analysis, the prognostic importance of each factor was studied. By a case‐control technique with individual matching for the identified independent predictors of recurrence, the additional prognostic information given by type and grade of inflammatory response, presence of vertical growth phase, mitotic rate/mm2, and histologic ulceration of the tumor was assessed. Results. After a median follow‐up time of 50 months, recurrent disease developed in 26 patients (4%). There was no difference in recurrence rate between patients treated with narrow (1–2 cm) or wide (5 cm) excision. Anatomic site, tumor thickness, level of invasion, and tumor regression were found to be independent prognostic factors in the multivariate analysis. In the case‐control study, only grade of inflammatory reaction added significant prognostic information. No subgroup could be identified that was without risk of recurrent disease. Conclusions. Thin melanomas do not seem to constitute a separate form of melanoma, but compose one end of a continuous spectrum of biologic behavior.

In all age groups among men, living alone is significantly associated with reduced CMM-specific survival, partially attributed to a more advanced stage at diagnosis. This emphasizes the need for improved prevention and early detection strategies for this group.