If Julius Caesar lived to invade Parthia?

[Quintius Clavus]

One of the interesting things about the Roman invasions of Parthia was that they could conquer the cities, many of whose occupants were Greek, but they couldn't do much in the hinterlands away from those cities or away from the great rivers, the Euphrates and Tigris rivers. The Parthians were a tribal society, though much more sophisticated than the Germans, of course. After the several Roman attempts to capture and hold Parthian territory, the Greeks in the cities must have gotten fed up, because, ultimately the Romans didn't/couldn't stick around to protect them and they must have faced some punishment from their Parthian overlords for any support given to the Romans.