Everything depends on the wave propagation in a given line structure.
If you have a twisted-line cable, then the AC or RF power travels in it using the "differential" mode. If the line is well balanced ad far from any other conductors, it would not radiate. Once there appears a close conductor, common-mode currents are induced in it, and radiation can occur due to it. The only good solution is to surround the twisted-line with a conductive tbe, so nothing can radiate outside.