So you have been planned for a total neoadjuvant therapy. Wherein now you will receive chemotherapy for 6 -8 cycles. This is a recent approach and its shown that it causes complete shrinkage of tumour and some patients may have a disappearance of tumor as well (which is called as a PcR). This is standard and please continue with it. The itching must be because of radiation, it will go away in due course of time. CEA coming down is a good sign as well which means that the tumour is responding to the treatment taken.