The highest scoring Scrabble word containing Myoma is Leiomyomata, which is worth at least 18 points without
any bonuses.
The next best word with Myoma is leiomyomas, which is worth 17 points.
Other high score words with Myoma are
myomas (13),
myoma (12),
myomata (14),
myomatous (16),
and
leiomyoma (16).