Hi, Lori. I'm very sorry to hear of your bad news. I suppose the most important thing to know is that marginal zone lymphoma is generally slow growing (the word used is 'indolent'). Sometimes treatment isn't even started for many months. A lot depends on the subtype, which is one of these three: MALT, Nodal or Splenic.
MALT is the most common subtype, and might be treated just with antibiotics when it is located in the stomach. But since your husband's lymphoma was only found when it was already at an advanced stage, I'd have to guess that the type he has is the Nodal marginal zone lymphoma. Is that correct? Has he been told that the docs are only going to observe him for now, with no treatment starting yet? This is called 'watch and wait'.
The Nodal subtype starts in the lymph nodes, not in the digestive tract.
The treatment for Nodal marginal zone lymphoma might be rituximab, which is very mild as far as side effects. It's not at all like the harsh chemo that everybody has heard about.
Please feel free to ask any questions whatsoever, and I'll try to be of help.
"I’m just confused that they say it’s a slow growing cancer but he is already in stage 4."
I would take that to mean that the lymphoma was there for a long time, slowly growing but without being noticed. It wouldn't be noticed without bumps in the neck or underarms or other places that can be seen or felt. It also wouldn't be noticed unless/until it was causing problems, such as with internal organs.
"So his diagnosis with the second opinion with Mayo is marginal zone lymphoma involving multiple extranodal sites."
Let's just take a moment for the terminology. Most lymphomas start in lymph nodes. When outside of lymph nodes, it is called 'extranodal' -- and mostly that occurs in the digestive tract because the digestive tract is lined with cells that are just like the cells in lymph nodes. MALT is the name for when extranodal marginal zone lymphoma is in the digestive tract. But extranodal marginal zone lymphoma can also be in other places besides the digestive tract.
"My husband does have a mass in his left kidney."
This might be why they want to start treatment right away, to save the kidney. Is the kidney near to failing?
Or else they want to start treatment right way because the lymphoma is in multiple sites and they fear it will keep spreading.
I will say that extranodal marginal zone lymphoma in the kidney is extremely rare because the kidney doesn't contain any cells like the ones that are in lymph nodes.
Are you satisfied, with the 2nd opinion, that this is the correct diagnosis?
"2 drugs, Rituxan and Bendamustine"
The combination of Rituxan with bendamustine looks pretty good, as far as effectiveness. The overall outlook looks pretty good, too. We can discuss that, if you like.