Clinical implications of distinct metastasizing preferences of different melanoma subtypes.

BACKGROUND: The incidence and mortality of malignant melanoma have been rising during the past decades, the latter being due to the high invasion capacity and the metastatic potential of melanoma cells to distant organs. OBJECTIVE: We investigated the distribution pattern of melanoma metastases taking into account different clinicopathological subtypes of melanoma. METHODS: We studied 310 stage IV (AJCC 2009) melanoma patients retrospectively with regard to potential correlations between frequency and occurrence of metastasis and the genetic background and pathological/clinical melanoma subtypes. For all patients, the time to distant metastasis (TTDM) and the distribution patterns of metastases were analyzed and correlated to the median survival time. RESULTS: Superficially Spreading (SSM) and Nodular melanomas (NMM) spread to the brain more frequently than Acrolentiginous (ALM) and Mucosal (MM) melanomas (p = 0.0012). The preference to affect the skeleton was significantly higher for ALM and MM in comparison to SSM and NMM (p = 0.0049). Lentigo maligna (LMM) tumors showed a significantly lower metastatic spread to distant lymph nodes (p = 0.0159). BRAF mutant versus wildtype tumors showed no significant differences concerning localization of metastasis but patients with BRAF mutant tumors were significantly younger at primary diagnosis and had a significantly shorter stage IV survival (p = 0.0106). CONCLUSION: This study shows a clear distinction of melanoma subtypes with regard to metastasizing preferences. Further knowledge about melanoma subtype specific characteristics, including molecular markers predictive of homing preferences, may help to understand and manage this heterogeneous disease in terms of prognosis and follow-up procedures.

Analysis of 10 km swimming performance of elite male and female open-water swimmers.

This study investigated trends in performance and sex difference in swimming speed of elite open-water swimmers at FINA 10 km competitions (i.e. World Cup races, European Championships, World Championships and Olympic Games). Swimming speed and sex difference in swimming speed of the fastest and the top ten women and men per event competing at 10 km open-water races between 2008 and 2012 were analysed using single and multi-level regression analyses. A total of 2,591 swimmers (i.e. 1,120 women and 1,471 men) finished 47 races. Swimming speed of the fastest women (1.35 ± 0.9 m/s) and men (1.45 ± 0.10 m/s) showed no changes across years. The mean sex difference in swimming speed for the fastest swimmers was 6.8 ± 2.5%. Swimming speed of the top ten female swimmers per event was 1.34 ± 0.09 m/s and remained stable across the years. The top ten male swimmers per event showed a significant decrease in swimming speed over time, even though swimming speed in the first race (i.e. January 2008, 1.40 ± 0.0 m/s) was slower than the swimming speed in the last race (i.e. October 2012, 1.50 ± 0.0 m/s) (P < 0.05). To summarize, swimming performances remained stable for the fastest elite open-water swimmers at 10 km FINA competitions between 2008 and 2012, while performances of the top ten men tended to decrease. The sex difference in swimming speed in elite ultra-swimmers (~7%) appeared smaller compared to other ultra-distance disciplines such as running. Further studies should examine how body shape and physiology of elite open-water ultra-distance swimmers influence performances.