B‑cell lymphoma affects patients in ways they do not always expect, especially when it comes to their immune system. As nurses, we see this every day. Patients may come in worried about cancer itself, but over time they start noticing something else. They are getting sick more often, infections linger, and they do not bounce back the way they used to. A big part of that comes down to what the disease does to their B‑cells.
B‑cells are the part of the immune system responsible for making antibodies. These antibodies help us fight everyday illnesses like sinus infections, bronchitis, or even a common cold. When B‑cells are functioning normally, they create a diverse and effective antibody response. This is what keeps most people from developing frequent or severe infections. When the immune system is not working properly, everyday infections can become more frequent and more difficult to recover from.
In B‑cell lymphoma, the cancerous B‑cells develop in the lymph nodes, spleen, and bone marrow, the same places where healthy B‑cells normally develop. As these abnormal cells multiply, they replace the healthy B‑cells the body relies on to fight infections. Even though there may be many B‑cells present, they are not functional. They crowd out the healthy cells and interfere with normal immune function. Many patients end up with low immunoglobulin levels, especially IgG, which is the main antibody that protects against bacterial infections. This is why repeated infections become such a common issue.
Treatment for B‑cell lymphoma often includes medications like rituximab. These therapies work by targeting the lymphoma cells, but they also remove the remaining healthy B‑cells. Once those healthy B‑cells are gone, the body cannot make antibodies the way it used to. Some patients stay immunosuppressed for months or even years after finishing treatment. They may feel like they are constantly fighting infections.
This is where immunoglobulin therapy can make a big difference.
Immunoglobulin therapy (Ig) supplies patients with antibodies they cannot make on their own so they have better protection against infections.
There are three main ways patients receive Ig. It can be infused intravenously (IVIG), typically administered every 3 – 4 weeks in a clinic or at home. Depending on how the patient tolerates the infusion, doses are typically infused over 2 – 4 hours. Alternatively, Ig can be infused subcutaneously (SCIG) at home, often independently after being taught by a nurse. SCIG infusions are typically infused through multiple subcutaneous sites simultaneously (usually 2 – 4), shorter in duration (usually about an hour) and more frequently (usually weekly or biweekly). A third option is facilitated subcutaneous immunoglobulin (fSCIg), which uses recombinant human hyaluronidase to allow larger volumes of Ig to be infused into the subcutaneous tissue. This enables patients to receive larger doses less frequently, often every 3 to 4 weeks, while still benefiting from subcutaneous administration. fSCIg is typically infused in 1 or 2 injection sites and can often be administered at home after appropriate training. All three methods are effective, and the choice often depends on lifestyle, comfort, and how steady the patient needs their Ig levels to be.
In summary, lymphoma interferes with how the body makes antibodies, and treatment of the lymphoma can take away healthy B‑cells that produce antibodies. Without those antibodies, infections tend to occur more often and take longer to resolve. Ig therapy gives the body some of the immune support it is missing. It will not treat the lymphoma, but it can help patients reduce infections and feel more protected.
For patients who continue to get sick during or after treatment for lymphoma, checking serum IgG levels can provide helpful insight. If those levels are low and infections continue to recur, Ig therapy may be a good option to explore with the care team.
Sources:
- American Cancer Society. Non‑Hodgkin Lymphoma: B‑Cell Lymphomas. American Cancer Society, 2026.
- Leukemia & Lymphoma Society. Understanding Lymphoma and Immune Function. Leukemia & Lymphoma Society, 2026.
- American Academy of Allergy, Asthma & Immunology (AAAAI). Guidance on Hypogammaglobulinemia and Immunoglobulin Replacement Therapy. AAAAI, 2026.
