Man proposes to high school sweetheart on her last day of chemo

FLORIDA -- Talk about the sweetest proposal!

Lucas D'onofrio's girlfriend was diagnosed with Non-Hodgkins Lymphoma on February 13th and after her last chemotherapy session, he decided it was time to pop the question!

In a heartwarming YouTube video, Lucas plans the memorable moment with the help of family, friends and nurses at Boca Raton Regional Hospital.

Grab a tissue and watch Lucas get down on one knee and surprise the love of his life!