The 110 cartridge can sometimes be salvaged, though whether you can open it in a reusable manner in the dark and save the film is questionable.
One classic method to do one-off 16mm processing is to tape the 16mm film (in the dark, obviously) to a long enough fixed-out 35mm strip and load it into your regular 35mm reel. If you're going to shoot 16mm routinely, you'll probably want to either modify a plastic reel to the correct width, or get a stainless 16mm reel and learn to load it (does
not work the same as 35mm/120 stainless reels -- I have one, somewhere and have never gotten the film to go into it, even in the light). What I did, since I shoot Minolta/Kiev 16 format, was to build an ABS drain pipe tank with pour-through light trap and a sealed core (to reduce liquid requirements -- takes less than 80ml for a 120-length roll of 16mm). Film is taped to the core, core loaded into the pipe, fill cap installed in the dark, then it's just like any daylight tank -- except it takes far less liquid.
(Pentax Spotmatic SP, Super Takumar 50 f/1.4, Tri-X, Caffenol
(Same as above)
As I recall, I later made a longer tank section and core to accommodate longer film than the standard Minolta 16 size of about 20 inches. I have not, however, located this tank since getting my darkroom built.