Having just read through your synopsis. the obvious conclusion is that chemo ACTUALLY usually shrinks tumor at a higher rate AND PRIOR TO elevation of the risk of metastases, and is therefore a very valuable first step in treatment, especially in cases of highly aggressive tumors where rapid response is vital. (Empahsis on FIRST step).

Going to the article abstract

Chemotherapy-induced TMEM activity and cancer cell dissemination were reversed by either administration of the TIE2 inhibitor rebastinib or knockdown of the MENA gene.

would indicate that only a careless course of treatment would ignore chemo followup with either or a combination of those treatments, or

"One approach would be to obtain a small amount of tumor tissue after a few doses of preoperative chemotherapy. If we observe that the markers scores are increased we would recommend discontinuing chemotherapy and having surgery first, followed by postoperative chemotherapy."