Hello , thanks for reaching out. While I don't have personal experience with breast cancer and psoriatic arthritis, I do hope that any of our community members who do (or even have experience with any type of cancer and PsA) see your question and share their experiences with you here. We did have a community member post about dealing with cancer and PsA (from several years ago) and I will share a link to that a forum with you, https://psoriatic-arthritis.com/forums/dealing-with-cancer-and-psa. You might also be interested in this article about PsA and cancer risk, https://psoriatic-arthritis.com/clinical/cancer-risk.
Is this something you are currently going through? Did your rheumatologist and/or oncologist say anything about staying on your immunosuppressant? While I hope you get helpful feedback from other members here, please don't hesitate to have a conversation with your medical team, especially if you have questions about medication changes and how that might change depending on cancer treatment.
This community is here for you, so please reach out here anytime. Sending you gentle hugs. -- Warmly, Christine (Team Member)