Mr. Mutombo, who did not begin playing basketball until adolescence, retired with the second-most blocked shots in league history.
Dikembe Mutombo, who arrived at Georgetown University as an international student with aspirations of being a doctor but became a towering presence in professional basketball and a dedicated humanitarian in his native Democratic Republic of Congo, died on Monday. He was 58.
The cause was brain cancer, according to the National Basketball Association, which announced the news.
Mutombo did not play basketball until midadolescence, having preferred soccer as a child. An older brother, Ilo, and his father, Samuel, encouraged him to try the sport in which his outsize frame, which ultimately stretched to 7 feet 2 inches, combined with his athletic agility could be of greater benefit.
He wound up playing 18 seasons in the N.B.A. for six teams, retiring with the second-most blocked shots in league history behind Hakeem Olajuwon, another African-born center. He was known for his trademark finger wag, a provocative pose he used to dissuade shooters from challenging him at the rim.
A full obituary will follow.
