The businesswoman and mother-of-three receives the bombshell news following a routine smear test later this year, just after she has finally made a choice between husband Greg and ex-partner Max Branning in the climax to their current love triangle story.
EastEnders producers have worked closely with various experts and charities including Jo's Cervical Cancer Trust and Macmillan Cancer Support while researching the storyline with the aim of accurately reflecting and highlighting the issue.
Confirming the plot, EastEnders' executive producer Bryan Kirkwood commented: "During the summer, EastEnders viewers will see Tanya receive the devastating news that she has cervical cancer. EastEnders has worked closely with experts in the field to ensure we accurately portray this sensitive issue.
"Viewers will see how Tanya, a mother of three, will use her inner determination to deal with what will be one of the toughest challenges of her life."
Meanwhile, Robert Music - Director of Jo's Cervical Cancer Trust - added: "As the UK's only charity solely dedicated to informing and supporting women affected by cervical abnormalities and cervical cancer, we think it is fantastic that EastEnders has decided to highlight the issue of cervical cancer. This is a disease that affects thousands of women and their loved ones in the UK every year, and for many can be preventable by taking proactive steps, such as attending cervical screening when invited.
"EastEnders have gone to great lengths to research this story with us and we hope that by showing this storyline to its millions of viewers, it will not only raise awareness of cervical cancer but also help the public to be more informed about this issue."
Ellen Lang, senior Macmillan cancer information nurse, added: "Cervical cancer is sadly diagnosed in thousands of women every year in the UK, so we congratulate EastEnders for tackling this difficult subject that affects so many people.
"822 people, like Tanya, are diagnosed with cancer every day. Most will feel overwhelmed when they are told that they have cancer, especially breaking the news to children and loved ones. It's vitally important that the cancer patient, and their family, get the support they need. We hope that anyone watching who is affected by this issue knows that they can get the support they need from Macmillan Cancer Support."
News of Tanya's shock diagnosis follows weeks of speculation over the character's future following previous hints that she would receive "a huge, life-changing shock" in the weeks ahead. Jake Wood, who plays Max, had also confirmed that a "big twist" was in store.
A show source told the newspaper: "Stefan's exit will come shortly after he discovers what Tanya has been up to."
Following her diagnosis in a few weeks' time, Tanya's illness storyline is expected to continue airing across the autumn.
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