Etumba attended and graduated from the Royal Military Academy in Belgium before joining the Forces Armées Zaïroises. He held important positions in the Alliance of Democratic Forces for the Liberation of Congo during the First Congo War and Second Congo War. In 2007 he was appointed Chief of Staff of the Congolese Navy. He was made Chief of Staff of the Armed Forces the following year. He retired from the post on 14 July 2018. He subsequently worked for Emmanuel Ramazani Shadary's presidential campaign organisation.