Actress Manisha Koirala , who played Sanjay Dutt’s mother Nargis Dutt in the upcoming “Sanju” , says she was shocked when she saw Ranbir Kapoor as Sanjay Dutt and couldn’t differentiate between them. Manisha and Sanjay Dutt's mother Nargis Dutt , both suffered from cancer. But only Manisha Koirala survived through.