S/PDIF-how different than an IC?

If you don't match characteristic impedance between source, cable, and destination you might get reflections in the cable on impedance boundaries.  These reflections can modify (add to) transition edge.  Such modification, can create staircases on the signal transition.  It makes variation in exact moment of level recognition - a time jitter.  This time jitter translates to noise in frequency domain.
This characteristic impedance is pretty much SQRT(L/C).  Inductance and capacitance in the cable depend on geometry and dielectric.  Every cable has characteristic impedance.  The chances are, that that your IC have impedance that is very close especially to destination (DAC).  You often pay for high purity metals or very low absorption dielectric in analog IC, that are not important in S/Pdif cable.  In addition, reflections in the cable might miss the edge originating them (hence 1.5 min recommendation) and you might be OK even when it is mismatched.  You can experiment, but I would start with inexpensive 75 ohm coax.  Main factor here is impedance matching and inexpensive cable might be better than fancy one.
Also, recommendations/reviews posted make no sense, since it is system dependent.

Thank you Kijanki! 
Zardozz-are you sure? What you state does not match the limited understanding I have. 

+1 @kijanki.

Blue Jeans Cable sells an SPDIF cable that seems to be well engineered and for 3-foot length is $19 plus freight. I have a couple of their SPDIF cables that I use when I need one. I had them made with yellow cabling, so I don’t mix them up with ordinary interconnects.

Like others have said, you can technically use a standard IC for a digital S/PDIF connection.  It will work because they are both just a wire that is connected using RCA plugs.  However, the IC is likely not going to perform as well because of the shielding and impedance requirements of the S/PDIF specification. 

The specificaion states a recommended use of BNC connector due to the 75 ohm design.  Most manufacturers just use RCA because this was a trend started a long time ago.  The problem is that RCA has an actual impedance of about 30-35 ohms.  This means it is more likely to have signal reflection problems.  This occurs when the digital pulse hits the receiver on the DAC side and actually produces a pulse reflection (like a sound wave reflected off a wall).  That reflection travels back down the cable to the source and causes distortion and inaccuracies on additional transmitted pulses.  The audible result is loss of high frequency resolution or other audio inaccuracies. 

Also, I always recommend 2 meter cable minimum to reduce reflections, even on BNC cables.