|
| Study | Male : female | Age of onset | Percent of tumors in the head and neck |
|
| Asian | | | |
| Present study | 1 | 68.9 | 100 |
| Zhang et al. [24] 1993 (Japan) | 0.94 | 58.8 | 80 |
| Ikeda et al. [1] 1989 (Japan) | 1.1 | N/A | 73.6 |
| Kikuchi et al. [22] 1996 (Japan) | 0.97 | 59.1 | 75.3 |
| Takenouchi et al. [27] 2001 (Japan) | 0.93 | 67.1 | N/A |
| Yap [32] 2010 (Malaysia) | 1.05 | 60.9 | 82.8 |
| Black African | | | |
| Mora and Burris [15] 1981 (US) | 0.82 | 59 | 76.3 |
| Abreo and Sanusi [2] 1991 (US) | 0.73 | 68.5 | 88.3 |
| Itayemi and Oluwasanmi [16] 1974 (Nigeria) | 0.72 | 41.1 | 57.9 |
| Caucasian | | | |
| Reizner et al. [25] 1993 (US) | 1.93 | 56.5 | 54.7 |
| Green [13] 1982 (Australia) | 2.02 | N/A | 61.8 |
| Czarnecki et al. [12] 1992 (Australia) | 1.95 | 51.9 | 61.7 |
| Roenigk et al. [11] 1986 (US) | 1.15 | 63.8 | 58.8 |
| Chuang et al. [9] 1990 (US) | 0.85 | 64.6 | 83.9 |
| Swerdlow [14] 1985 (UK) | 1.2 | N/A | 92 |
| Gallagher et al. [7] 1990 (Canada) | 1.2 | N/A | 68.8 |
| Dahl et al. [8] 1992 (Sweden) | 0.97 | N/A | 60.2 |
|