Diagnosing diffuse large B-cell lymphoma usually involves several tests, including blood work and imaging, along with a physical exam.

Diffuse large B-cell lymphoma (DLBCL) is a type of non-Hodgkin’s lymphoma. An estimated 25–30% of people with non-Hodgkin’s lymphoma have this type.

Lymphoma is a blood cancer that develops in lymphocytes (a type of white blood cell). Lymphocytes are an important part of your immune system. Healthy lymphocytes fight infections to keep you well.

B cells are a type of lymphocyte. When DLBCL develops, abnormal B cells grow faster than healthy B cells, and the abnormal cells crowd out healthy white blood cells.

There are different types of lymphoma. Doctors can use tests to find out which type of lymphoma you have. This information helps guide treatment decisions.

As part of a DLBCL diagnosis, you’ll likely have a physical exam and several tests.

Here’s more about how doctors diagnose this type of lymphoma.

There is no routine screening for DLBCL. This type of cancer can cause swollen lymph nodes, which is often the reason that people first seek medical attention.

A healthcare professional will first consider your signs and symptoms. DLBCL does not usually have symptoms in its early stages, so it’s most often diagnosed at an advanced stage.

Along with swollen lymph nodes, symptoms of DLBCL include:

  • an unexplained fever that keeps coming back
  • night sweats
  • unexpected weight loss

A healthcare professional will do a physical exam to check your lymph nodes, especially under your arms and in your neck and groin. Although lymph nodes are also found in other parts of your body, the lymph nodes in these areas are most likely to be swollen.

Cancerous B cells grow larger and more quickly than healthy B cells. Swelling happens when the abnormal cells build up in your lymph nodes.


A physical exam is not enough to diagnose DLBCL since the symptoms can be similar to those of other conditions. That’s where further testing comes in. Doctors can use the findings from these tests to make the correct diagnosis.

Here are some of the tests your doctors may use in the process of diagnosing DLBCL:

  • Blood work: A blood test can provide more details about the health of your blood cells. But this is not enough to make a diagnosis.
  • Biopsy: In this procedure, a healthcare professional removes a sample of your cells, often from a swollen lymph node, and sends it to a lab for examination under a microscope. DLBCL cells are larger than healthy lymphocytes. They also have markers that indicate that they grow and divide more quickly than healthy cells.
  • Imaging tests: Tests such as X-ray, CT, MRI, and PET scans can be helpful to find out whether cancer has spread to other parts of your body.
  • Bone marrow biopsy: Bone marrow is where blood cells are made. In a bone marrow biopsy, a healthcare professional uses a needle to remove a sample of your bone marrow cells. Doctors then study the cells to look for cancer.
  • Lumbar puncture: A healthcare professional uses a needle to remove a small amount of your spinal fluid. Doctors then study the fluid to look for cancer cells to see whether lymphoma has spread to your brain and spinal fluid.

Stages of DLBCL

DLBCL is a fast-growing type of cancer. Since white blood cells are found throughout your lymphatic system, DLBCL spreads easily in your body. Most of the time, DLBCL is diagnosed at stage 3 or 4.

When diagnosing cancer, a doctor will also determine which stage the cancer is in. Staging is based on the amount of cancerous cells found in your body, whether the cancer has spread, and how much it has spread.

DLBCL has four stages:

  • Stage 1/1E: Cancer cells are found in one place — either in one lymph node or in one place outside your lymph nodes, often an organ in your lymphatic system (1E). The lymphoid organs include your tonsils, spleen, and thymus. The “E” means “extranodal,” which indicates that the cancer is outside your lymph nodes.
  • Stage 2: Lymphoma is found in two lymph nodes or a lymph node and a lymphoid organ. Both sites of cancer are in either the area of your body above your diaphragm or below your diaphragm.
  • Stage 3: Cancer has spread to sites above and below your diaphragm.
  • Stage 4: Lymphoma has spread to parts of your body that are not part of your lymphatic system, such as your liver or lungs.

You may feel like you’ve had a lot of testing done before you finally get a diagnosis. Your doctor may share test results with you, or they may refer you to an oncologist right away. An oncologist is a doctor who specializes in cancer. They can explain exactly what the results mean and what the next steps might be.

Your doctor or oncologist will tell you more about your type of cancer, the stage, and what this means for you.

After receiving a diagnosis of DLBCL, you’ll probably have a lot of questions. Your oncologist will do their best to answer your questions and guide you in making decisions about your best treatment options.

DLBCL is a fast-growing type of cancer, so you’ll start treatment as soon as you can. You may feel in a rush to get started. Although it’s best to start treatment quickly, you can still take time to ask questions and make sure you understand what the plan is.

Consider asking about any resources and supports in your area that might be helpful, such as support groups or programs to help with the costs of cancer.

The first-line treatment for DLBCL is a chemotherapy regimen known as R-CHOP.

R-CHOP includes:

  • rituximab, a type of targeted treatment
  • cyclophosphamide, a chemotherapy medication
  • hydroxydaunorubicin hydrochloride (often called doxorubicin), a chemotherapy medication
  • vincristine (Oncovin), a chemotherapy medication
  • prednisone, a steroid medication that reduces inflammation and helps chemotherapy work better

The R-CHOP regimen includes six cycles of chemotherapy. Cycles are typically 3 weeks apart. Rituximab and the chemotherapy medications are intravenous (IV) medications. Prednisone is an oral medication.

Although R-CHOP is the standard first treatment, your doctor may also discuss other options with you.

Other DLBCL treatment options include:

  • other chemotherapy medications
  • targeted therapies
  • stem cell transplant
  • immunotherapy treatments

The best treatment options for you will depend on several factors, such as your stage of cancer, age, and overall health.

Although R-CHOP works well to treat DLBCL, the cancer will not always respond to it. About 30–40% of people with DLBCL need another treatment, either because R-CHOP does not work for them or because their cancer returns.

If that happens, your doctor will discuss potential next steps with you.

There are also ongoing clinical trials for people with DLBCL. You can ask your doctor whether a clinical trial is an option for you.

The overall 5-year relative survival rate for all stages of DLBCL is 65%. That means someone with DLBCL is 65% as likely as someone without cancer to still be alive 5 years after diagnosis.

Diffuse large B-cell lymphoma (DLBCL) is the most common type of non-Hodgkin’s lymphoma. Since there are many types of lymphoma, testing is important to find out exactly what type of lymphoma you have.

Certain treatments work better for different types of lymphoma. It is fast-growing, so treatment usually starts quickly. R-CHOP is the regimen that is considered the first-line treatment for DLBCL.