After TLI burn, just before Transposition, Docking and Extraction, the later design crafts jettisoned 4 pieces of the SLA fairing/shroud. These 4 pieces supposedly would follow similar path as the CSM/LM assembly, with the difference that they wouldn't reduce their speed for Lunar Orbit Insertion. What happened to them? Are they still in Earth orbit somewhere out there (they wouldn't leave Earth gravity influence since the spacecrafts after TLI burn didn't quite reach Earth escape velocity) or did they collide with something during all these years?
This paper by Dan Adamo states that their fate is unknown.
Other Apollo Program hardware certainly accompanied some of the components cited here into interplanetary space. Unfortunately, there are no empirical data relating to these objects' trajectories. Likely the largest such undocumented disposed components are four spacecraft/LM adapter (SLA) panels explosively jettisoned from each S-IVB at Command-Service Module (CSM) separation during trans-lunar coast. Although these jettisons were performed on missions Apollo 8 and Apollo 10 through Apollo 17, missions Apollo 13 through Apollo 17 targeted S-IVB disposal via lunar impact. In any of these cases, zero to four SLAs may have entered interplanetary space.
The four pieces of the SLA fairing would follow a similar path as the third stage S-IVB of the Saturn V. The SLA pieces were separated by explosive devices only, so their additional acceleration was very, very small. See apollomaniacs.
After Wikipedia, the S-IVB stages of the missions 8 to 12 are in heliocentric orbits now and of the missions 13 to 17 were crashed on the lunar surface as seismic tests.
In my opinion, the SLA pieces shared the fate of the S-IVB stages.