The 38-year-old former model, who won the Miss Universe crown in 1994, said these children know how to celebrate life.
"I celebrated 20 years of winning Miss Universe with a 100 little kids today. All cancer patients who truly know how to celebrate life! Salute," Sushmita posted on Twitter.
The 'Main Hoon Na' star also watched Amole Gupte's 'Hawaa Hawaai' with the patients.
"Here we are!! My peaceful warriors and I. Watching 'Hawaa Hawaai' and celebrating our spirit that Cancer can't beat," Sushmita added by posting a picture.