The Glasgow-born actress, 51, was best known for her role as Sheila Ramsay in the STV soap High Road.
She died in hospital in Glasgow on Saturday, with her family at her bedside.
The mother-of-one was diagnosed with the disease in 2009 and underwent a mastectomy, but the cancer returned in 2010.
She was admitted to hospital last Wednesday and her death at the weekend came as a shock to her former colleagues.
Comedian Andy Cameron, 72, who played Chic Cherry in the soap, said: "I got the call this morning to tell me Lesley was dead and I was gutted.
"She was a real trouper, you couldn't meet a nicer person."
Gary Hollywood, who played her adopted son Dominic in the Loch Lomond-set soap and now stars in TV comedy Mrs Brown's Boys, said he was "devastated" about Lesley's death.
After the STV show was axed in 2003, Lesley moved mainly into theatre work and was a panto favourite in west Scotland.
Elizabeth Partyka, deputy director of channels at STV, added: "We are sorry to hear of the passing of Lesley, who will be fondly remembered by the many fans of Take The High Road.
"It remains one of the UK's longest running drama series and Lesley's contribution to its success was significant."
The actress had a number of other television shows to her credit.
These included the STV series The Prime Of Miss Jean Brodie in 1978 and The Spaver Connection in 1984 with John Gordon Sinclair.
She lived in Milton Of Campsie, Dunbartonshire, and is survived by her 17-year-old daughter, Marnie, from her marriage to former husband Calum Thompson.