Metastasize rhymes with:
fantasize, romanticize, deemphasize, emphasize, fantasize, hypothesize, ostracize, overemphasize, reemphasize, romanticize, synthesize
Metastasize sounds like:
matsushita's, medicates, metastasis, midgets, midgett's, midwest's, mindsets, mitigates, mitsotakis, montesdeoca