Tennis champ Leander Paes, 30, is being treated for a brain lesion in an American hospital.

He checked himself into the emergency room of a local hospital near his Orlando home on August 17 after suffering from severe headaches for three days.

He was transferred to MD Anderson Cancer Centre in Orlando on Tuesday, hospital spokeswoman Michelle Lynch said.

After an initial brain CT scan and MRI, Paes was told that he has a lesion in the left occipital region of the brain.

Tests are being conducted to determine the lesion's cause and a brain tumour has not been ruled out, Lynch said.