Table 1.
Epidemiological data for PPGLs.
| Parameter | HNPGLs | PHEO | Other Extra-Adrenal PGLs | ||
|---|---|---|---|---|---|
| CPGL | MEPGL | VPGL | |||
| Mean age at diagnosis | 40–50 * [7,8] | 55 [4] | 41–47 [4] | 40–50 [9] | 40–50 [9] |
| Female/male ratio | 2:1–8:1 ** [10,11] | 3:1–9:1 [12] | 2:1–8:1 [12] | 1:1 [9] | 1:1 [9] |
| Multifocal cases, % | 10–25 [1] | 10–50 [13] | 10 *** [14] | 8 [15] | 33 [15] |
| Metastatic cases, % | 4–6 [12] | 2 [12] | 16–19 [10,12] | 10 [9] | 2.5–50 [9] |
CPGL, carotid paraganglioma, MEPGL, middle ear paraganglioma, VPGL, vagal paraganglioma. * Metastatic cases are characterized by a 10-year earlier age of diagnosis. ** The ratio is higher in populations living at high altitudes under hypoxic conditions. *** Incidence of multiple paragangliomas increases to 30–40% in patients with a positive family history.