Dikembe Mutombo's heartbroken over the loss of Matadi Sela Petit, but incredibly ... he's staying positive, and says the tragedy's only strengthened his focus on helping people.
The Basketball Hall of Famer tells TMZ ... he's been working with the 8-year-old boy's family to transport his body back to the Democratic Republic of Congo for a proper burial, which should happen soon. He says dealing with the loss is tough ... but everyone's hanging in there.
We broke the story ... Dikembe flew the child from Africa to the U.S. earlier this month in hopes of removing the large tumor from his face, so he could return to his home and live a normal, happy life.