Last name Phansithoum (Phansithoum 
) , in the entire world, is a rare cognomen. The cognomen Phansithoum is habitual in South-eastern Asia, particularly Laos, where it is quite a rare surname.
| VARIANT | COUNTRY |
|---|---|
| Phansithoum | Laos |
Bounxou, Soulichanh, and Thongvilay