Leonard,
Overall I would say you're doing well, and kept the weight loss to a minimum of 6 pounds. Doctors do get concerned with 5% unintentional weight loss from your pretreatment weight during a 6 month period, which is the biggest cause of treatment stoppage, and poorer outcome, and if continued, and may require intervention such as a peg or nasal tube, and others. Many factors influence the weight loss due to pain, swallowing difficulty, dry mouth, infections, cancer itself, physiological, etc, including cancer cachexia, which is difficult reverse, gain back, even with increased nutrition due to metabolic changes, is mostly skeletal muscle, and each need to be treated accordingly. I lost significant weight several times, over 120 my first round with chemo, 40 just with radiation, 10 here and there during other treatments, and took several years to gain back 50lbs.
Radiation effects start becoming more difficult from the 3rd week, and more difficult as time goes on, even up to 3 weeks post treatment being the worst.
As far as thick mucus, that's a result of the radiation to the major salivary glands, more so in the parotid, which basically kill thin mucus, so you're left more with the thick. Usually thick mucus starts subsisting two to three weeks at the end of your treatment when the other glands start producing more and or glands start recovering depending if spared, the radiation dose, and areas. Overall, it can take up to 2-3 years to recover, if not longer, plus radiation has acute toxicities, lasting up to 3 months, and long term, longer than three months that can occur months, years later.
To help thick mucus you can sleep on an incline, use a humidifier, keep hydrated, brush/rinse out mouth, a steam shower, usual salt water baking soda rinse, rinsing with seltzer, pineapple or papaya juice, even used diluted meat tenderizer.
I don't see mentioning working with a registered dietician, a Speech and Swallow Therapist, SLP, which I recommend. When I did radiation I had my mouth sprayed out daily in radiology, which helped mucocitus,and thrush, which are sometimes difficult to differentiate and occur concurrently, along with other conditions, including bacterial or viral infections, which need to be treated appropriately, and had extra hydration in radiology, in addition to being prescribed NeutraSal for Mucocitus & Dry Mouth, Nyststin for thrush, Magic mouthwash for pain in order to swallow, opioids.
OCF has a nice page to help you through the treatment process, and recovery, and recommend reading that, and if you have time, through the various blogs.
http://www.oralcancerfoundation.org/treatment/Good luck, and if you have any questions, ask.
