The 50-year-old actress is now free of the disease after undergoing a lumpectomy followed by chemotherapy, a course of radiation treatment and additional medication in response to a tumour being detected during an ultrasound late last year.
The Office star revealed on Instagram: “Back in October 2023, I posted a photo of myself on Instagram preparing for my routine mammogram with a joking reminder to ‘take care of your ticking time bags’ a la Michael Scott. After inconclusive results on that mammogram due to dense breast tissue my doctor ordered a breast ultrasound.
“They found something in my left breast. A biopsy was ordered. Then, on December 1, 2023, I learned I had stage 1 triple positive breast cancer.”
In January, the Office star underwent a lumpectomy to remove the tumour, which hadn’t spread, but due to the “aggressive nature” of her cancer, she needed further treatment so underwent 12 rounds of chemo beginning the following month, and three weeks of radiation in June and she is now “feeling great”.
Jenna urged women to undergo their annual mammograms as if she hadn’t, things could have been “much worse”.
She wrote: “I’m making this announcement for a few reasons. One, I’m ready to ditch the wigs. Two, to implore you to get your annual mammograms. You can also ask your doctor to calculate your Breast Cancer Risk Assessment Score and get any additional screenings required. I’m serious, call your doctors right now.
“If I had waited six months longer, things could have been much worse. It could have spread.
“Seeing women post photos of their mammogram appointments on Instagram needled me into setting my own (which I was late for). I’m so glad I did.
“Consider this your kick in the butt to get it done ... Suddenly everything in your life is geared around one thing: fighting cancer.”
The Blades of Glory actress - who has two children with husband Lee Kirk - thanked her medical team and friends, family and fellow cancer survivors for helping her over the last year and she is delighted to now be “cancer free”.
She wrote: “I’m happy to say that I was recently re-screened, and the treatments worked. I am cancer free. I will continue to be treated and monitored to help me stay that way.
“Again, don’t skip your mammogram … And know that should you get a breast cancer diagnosis, there is a village waiting to care for you.”