if I sync photos from PC to iphone via iTunes. post complete syncing, if I were to turn on my iCloud photos, the earlier synced photos via iTunes will be deleted?

I had backup my photos into PC, formatted my iPhone. Post re-format, I would like to re-sync back the photos from my PC to my iPhone via iTunes (I do not turn on iCloud Photo before I formatted my iPhone). After re-sync back my photos from my PC to my iPhone, when I were to re-turn on iCloud Photo, the earlier synced photos via iTunes will be auto deleted. Is there anyway to fix?