The once golf-ball-sized tumour, has now shrunk to 4mm in diameter.
Van Dijk said two things have helped her on her journey. First that her doctor never directly told her, 'you have cancer', and that she felt physically healthy going into chemotherapy.
"When the doctor found the tumour, he said it was cancerous - stage two, grade three.
"I have separated the cancer from the normal me.
"Fortunately, I found it early enough and felt quite strong going into this. The tumour didn't make me feel sick, going through chemo did."
Her diagnosis was a double blow. Newly married, this year was going to be about trying for a baby.
"I was diagnosed in January. Then it was a whirlwind from there – we had just enough time to do a round of IVF – we got a couple of embryos frozen – the following week I started chemo.
"Friends have said they are like my insurance policy, as they know someone who has been through chemo and got pregnant afterwards."
Rebecca will have a lumpectomy on July 10, then eight weeks later will start radiation.
"I feel like mentally I have got the worst done. I have closed one chapter and I am onto the next."
The turning point came when she attended a Look Good Feel Better class, a free workshop that helps combat the physical side effects of cancer treatment, as well as helping people regain confidence and their self-esteem.
"I went to Look Good Feel Better after my first chemo. On a Monday I noticed my hair was starting to come out, and my heart sunk. The class was the next day and we chatted and had a laugh about what we were going through. I knew then it was going to be okay.
"After my class I went to the hairdresser and we cut my hair really short – I got the confidence to do that through the class."
Look Good Feel Better is the recipient charity for Dry July 2018. It offers free classes around New Zealand to anyone undergoing any cancer, at any stage of treatment.
Rebecca is in the top 10 fundraisers for the Dry July campaign.
"I want to give back somehow - not only to the charities who helped me along the way - but also as a thank you to the community, my friends and family."
Van Dijk said battling through cancer is a humbling experience, "it alters your perspective on life".
"Little things that used to bother me don't matter anymore, at the same time there are also little things that I now appreciate more."