The 26-year-old was diagnosed last week with the disease, which affects the thyroid gland and often causes people to lose weight and feel fatigued, according to the National Grave's Disease Foundation.
The disease is treatable, but incurable.
The Montreal native was scheduled to participate in the final stage of LPGA Tour Q-school starting Wednesday in Daytona Beach, Fla.
Beisiegel has played on the LPGA Tour the past two seasons. After a promising rookie year, she struggled in 2005, making just two cuts and less than $7,000 in 19 events. That forced her to go through qualifying to earn a card for next season.
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