Yuvraj Singh is undergoing chemotherapy to treat a cancerous growth that may have been bothering him even while he produced his World Cup heroics last year.
The growth in his chest was originally thought to be benign, but has recently been diagnosed as malignant, and he traveled to the United States on Jan. 26 to seek treatment.
"It is a rare tumor and is cancerous, but it has been detected in stage-one," Singh's physiotherapist, Jatin Chaudhary, was quoted as saying Monday by the Press Trust of India.
"Doctors had to decide whether to continue medication or go for chemotherapy, but since parts of the tumor are just above the artery of his heart, there was a danger that while running it could burst. But it is 100 percent curable," he said.
Dr. Nitish Rohatgi, an oncologist in New Delhi's Max Hospital who has been co-ordinating with Singh's doctors in the United States, said the cricketer had been responding well to treatment.
Yuvraj Singh's mother Shabnam said in November that her son probably carried the illness through the World Cup in March and April last year, saying that the allrounder suffered from constant "bouts of coughing and vomiting" during the tournament and medical tests revealed a "golf-ball size lump over the left lung."
India's sports minister Ajay Maken has promised help to Singh.
"Wish Yuvraj a speedy recovery! Asking officials to find the quantum and nature of help required. Government should and will help him," Maken posted on Twitter.
The Board of Control for Cricket in India has wished Singh "a speedy recovery" in an e-mailed statement, in which it also asked the media to respect the privacy of Singh and his family members.
The 30-year-old Singh, man-of-the-tournament during last year's home World Cup-victory, last played for India during a home test series against the West Indies in November.
Singh has played 37 tests, 274 limited-overs internationals and 23 Twenty20 internationals.
He played a large part in India winning the World Cup for the first time since 1983, playing in all nine matches at the 2011 edition and contributing 362 runs at an average of 90 and taking 15 wickets at 25 with his left-arm spin.
Singh is also famous for striking six sixes in an over off England paceman Stuart Broad during the Twenty20 World Cup in 2007.
Singh's absence on India's current tour of Australia has been noticeable. India was trounced 4-0 in the test series and won just one of two Twenty20 matches before losing its opening one-dayer against Australia by 64 runs Sunday.
