Allyson,

When you were diagnosed or when you started treatment, did you apply for Family Medical Leave Act (FMLA) ?  If at any point since diagnosis, you requested benefits under FMLA, then you have formerly registered for accommodations and therefore there is no need to repeat it in your self evaluation.

The point of the self evaluation is whether you have been able to perform the position as described and the goals set for the position,with or without accommodations. When you were offered the new position, that would have been part of the agreement.

I suggest you focus on demonstrating how well you performed the position bouncing off of the requirement of the job and hopefully you can show how you went over and beyond the expectations.  I don't see any winning side to attempt to justify poor performance based on your medical condition.

Since HR and Management is aware of your challenges, you obviously work for a company where the culture is compassionate and they have accommodated you by providing a more appropriate position to make it easier on you. You might add your thanks to them and the company in your self evaluation, for their accommodations and compassion during a difficult year and that you plan to continue doing your very best to not disappoint the trust they have in you.

Whether you are applying for a position or a promotion, it is not appropriate nor beneficial to discuss your illness unless you are requesting  an accommodation under the FMLA or ADA (American Disability Act).

You may also want to contact with Cancer and Careers' legal experts to seek their advice.  My advice is coming from a perspective of an experienced Human Resource professional, as well as a Career Coach and Management Consultant.

Hope this is helpful to you.  Good Luck.  We always welcome feedback on how your approach went.

Margot