If my breast ca shows vascular invasion, how likely that the ca has metastasized to an organ? what abt micrometastases to an organ? will my chemo help

Totality of data...: In breast cancer there are various pathologic (eg vascular invasion) and molecular (her2 status, oncotype DX or mammaprint recurrence scores) that determine risk. Initial staging determines staging. The risks and benefits of chemotherapy are individualized based on the host (you) and tumor characteristics. That decision can be aided by tools such as adjuvant online! but needs careful consideration.

Their is a risk: The risk of systemic spread is higher when there is vascular invasion but it is not guaranteed. The idea behind chemotherapy is to kill any stray cells that may spread before they can establish themselves in another organ.