My suggestion would be to strongly advocate for a more aggressive approach to this process. Make an appointment with his oncologist. There is this test called a Pet scan that is much more effective for zeroing in on this lump if he has not had test so far. There is also the option of whether this lump can be biopsied. Ultimately you could get a second opinion. I would certainly consider this option for sure. These are my suggestions. I hope they give you some food for thought.

I had Rituximab treatment for B cell marginal zone Lymphoma and I had a positive response .In my experience it was a first class treatment. It is my hope that he has a good response also.
How are you doing Janet. I hope you have some support as you are certainly having some anxiety about your husband’s condition and perhaps some caregiving duties also.
I don’t know if you are interested but you can join the caregiver group on My Lymphoma Team. That group could be a helpful resource. My best wishes for your husband and for you. Stay in touch with me please. Perhaps we can get to share some of our stories beyond the lymphoma team.

He had a biopsy on gland enlarged on jaw which confirmed the follicular lymphoma 24th April. No one has suggested a biopsy on lump in chest (I don't think they are certain what it affects even after the PET-CT scan 26th July but there has been a comment in a letter to drs saying they're trying the Rituximab to avoid doing a bone marrow biopsy. Feels like second class treatment.

I had a biopsy on lump in groin which proved Fullicular Lymphoma- PetScan followed to establish stage of cancer.
In my case stage 3A- last of 6 chemo cycles this coming weekend.
After that another scan to see progress

Hubby has only been offered Rituximab on its own despite having a delay between symptoms with incorrect diagnosis by a PHYSICIANS ASSISTANT and actual diagnosis . Eventually determined as stage 4 with an indeterminable lump inside his ribcage which they are not sure what is, or what it is attached to. Feel now we have been fobbed off again and he should have been receiving a higher rate of treatment.