It says in the article there that the tumor is benign, so she doesn't have brain cancer. That's good news. That said, benign tumors can cause increased intracranial pressure and in turn cause headaches, seizures, and cognitive dysfunction, so obviously it can't be taken lightly.
That said, I don't see how anyone could question his choice. For those of you who have seen the Breaking Bad series, recall this scene...
https://www.youtube.com/watch?v=M5l8spk68CA...and the words at the end. Professional basketball (or any professional obligation for that matter) means nothing relative to family. Even if it's game 7 of the NBA finals.
One of my cousins had a sudden onset of a major headache one day - he had been having numerous headaches up until that point over a few years but ignored them - and went to the hospital where he was found to have a malignant brain tumor. He died a few days later at age 36.
Can't mess around with major health issues.