please dont take my post as rude. it is basically down to the niddy griddy with you.
from his pics you not only have some sort of abscess . the flat sunken in lobes on his head suggest that he is malnurished, dehydrated and has mouth area suggests he possibly has mbd. although it could be a birth defect but i dont think so in the case. your care for him needs to step up. im not going to ask you to fill a "how to ask form" to criticize your care. i can tell by his condition many things need to change. here is a basic care sheet for panthers. PLEASE follow what i am about to post.
he definitely needs a vets attention for the abscess but the rest you should be able to help with a change in care.
Cage:24x24x48' SCREEN cage lots of rope, vines and live plants if you can. live plants will help with the humidity. make sure you cover the soil with screen or large rocks. put cage as high up in the room as you can. not near any vents, fans or windows.
Lighting: 5.0 reptisun or reptiglo linear tube (length depends on cage size)/house hold bulb for basking. the house bulb watt will depend on how far your nearest branch is from the light and your ambient room temps.
***change UVB bulbs every 6 months.
Temps: basking temp around 90* for a male low 80's* for female / ambient temps 72* measure by digital guages.
Hydration: manual spray 2-5 minutes/2-3 times a day. provide a dripper.
Feeders: gutload (24 hours before feeding) with fresh veggies and fruits and once a week with sticky tongues gutload. Crickets, mealworms (as a snack), silkworms, hornworms, dubai roaches, reptiworms, BB flies. NO SUPERWORMS
Supplements: repcal calcium w/o d3 every feeding, repcal calcium w/d3 twice a month, repcal herptivite twice a month (i also rotate herptivite with reptivite)
heres a link to help him get rehydrated. if he has a appetite, he just needs fed the proper amount of food and frequency.
https://www.chameleonforums.com/blogs/ataraxia/454-dehydration-solutions-force-fluid-tips.html