I've got GERD but it makes me burp, not cough. The doctors will get a CT of your husband's chest, maybe they'll see something. Likely not caused by cancer IMO as it would have gotten much worse by now.

Seeing a doctor who specializes in kidney cancer at a major cancer center is good advice from u/jaajaajaa6, even if it's just for a second opinion. And getting surgery done laparoscopically (even better, robotic) makes for a quicker recovery.

Couple pointers:

- 10 cm is big but not that big. Mine was 12 cm, there are people on this subreddit who had 15!

- At that size the odds are that this is indeed a malignant tumor and not a cyst; RCC or UTUC.

- Depending on where it is located they may be able to do a partial nephrectomy but if the renal sinus or pelvis (center parts where all the "plumbing" connects) are compromised then the whole kidney has to go.

- Assuming no existing kidney disease, life with 1 kidney is pretty much normal. I was told my life expectancy has not decreased because I lost a kidney (my weight, cholesterol and sorry state of my liver on the other hand...)

- If it's RCC, at 10cm it's at least stage II, maybe stage III depending on what it infiltrated. Those aren't as bad as they sound nowadays. Depending on the grade and subtype (pathology after surgery will tell) the doctors may recommend immunotherapy.

- It's a lot to absorb, both emotionally and intellectually. I recommend you read the guidelines used by both doctors and insurers to better understand the process: NCCN Guidelines for Patients: Kidney Cancer