Update: the asker has clarified in comments that the flight they wish to skip is the final leg of the return journey, which alters the situation somewhat as there would be no subsequent trips under risk of cancellation.
However, my advice still stands - you need to talk to the airline, there is no other way to get the luggage off loaded at the interstitial airport, only the airline can change the final destination of the luggage.
One trick is, when checking the luggage in Korea, to ask for the luggage to be made available at the Turkey stop for "medical reasons", and if they ask why you cannot take said "medical reasons" in hand luggage (they should not, thats confidential medical information they are asking for), just respond that you will be carrying "sharps" and they need to be checked into the hold. I see no reason why the airline wouldn't provide the baggage on request.
I do not know the layout of Istanbul airport, so I am unsure if the airline may ask difficult questions such as "how do you intend to recheck the luggage items", especially if you need a Turkish visa to enter Turkey and
you may need to do that to recheck the luggage, I am not sure.
Old answer: You need to speak to the airline, because there is a very high chance that if you do not complete all legs of the outward bound journey (Incheon to Tirana) then the airline may cancel your return flight completely.
Speak to the airline and change the ticket to a multi-city ticket, where the outbound trip terminates in Turkey and the return trip flies from wherever you want to return to Korean from.
Related - Is is possible to skip the middle leg of a flight?