Singh is in London after a treatment for a malignant lung tumour in the US .
A TV grab shows Indian cricketer Yuvraj Singh , speaking on his 2011 World Cup performance in an interview , on Sunday .
cricketer is in London after a treatment for a malignant lung tumour in the US .
A TV grab shows Indian cricketer Yuvraj Singh , speaking on his 2011 World Cup performance in an interview , on Sunday .