In her early 40s, Brenda Cunnington was living life to the fullest—travelling, working at TMX Group in downtown Toronto, and raising her two kids, Jack and Katie. Then, in August 2017, she discovered a small lump in her left breast. Early testing confirmed it was a simple cyst, but because she had heterogeneously dense breast tissue and an area of calcification, she was advised to return for regular screening every six months.

For the next five years, Brenda’s mammograms all came back clear. Trusting the process, she believed any problems would be caught early. But in November 2022, she was blindsided by a diagnosis she never expected: invasive lobular breast cancer. What had first been dismissed as a cyst ruptured during a routine mammogram, and further testing revealed a 10-centimetre tumour that had already spread to her lymph nodes. “I can’t describe the shock,” Brenda says. “It came out of left field. I had never even heard of lobular breast cancer until I was diagnosed with it.”

Through her journey, Brenda has learned that lobular breast cancer behaves differently from other types of breast cancer and is often missed on mammograms, leading to later-stage diagnoses. Despite being the second most common subtype, less than 1% of breast cancer research funding is directed toward lobular cases. “That needs to change,” Brenda says.

For Brenda, advocacy has become a personal mission. She credits patient advocacy groups and organizations like Breast Cancer Canada for bringing visibility to lobular breast cancer and ensuring patient voices are heard. “Breast cancer is a club no one wants to be a member of, but when you join, it’s amazing the people who become part of your circle,” she says.

She is especially encouraged by the work of researchers like Dr. David Lim, supported by Breast Cancer Canada, who are studying why some breast cancers are still being missed. His research into gene patterns in invasive lobular breast cancer could lead to earlier detection, better treatments, and improved survival.

“Progress means change,” Brenda says. “With more research and more awareness, we can ensure fewer women are blindsided the way I was. That’s how we change the future for the next generation.”