Diagnosis

Diagnosing lymphoma is a step-by-step process that involves several healthcare professionals, each with specific expertise. These include specialists in clinical care (hematologists), surgery (such as general or thoracic surgeons), pathology (anatomopathologists), and molecular biology (biologists or biotechnologists).

In most cases, the diagnostic process begins when a specialist—such as a hematologist, oncologist, or surgeon—identifies a possible suspicion of lymphoma. This is based on a careful review of the patient’s medical history, a physical examination, blood tests, imaging studies, and, importantly, the analysis of a tissue sample obtained through biopsy.

A biopsy is always essential to confirm the diagnosis. It allows doctors to identify the exact type of lymphoma and choose the most appropriate treatment.

Medical history and physical examination

The doctor collects information about symptoms and medical history, and examines lymph nodes in the neck, armpits, and groin. The size of the liver and spleen is also assessed.

Imaging tests

Chest X-ray: a simple initial test that provides a basic view of the chest. It may be one of the first steps leading to suspicion of lymphoma and is also used during treatment to monitor possible infections.

Ultrasound: useful for evaluating superficial lymph nodes, as well as those in the abdomen and the spleen. It does not expose patients to radiation and is widely accessible.

CT scan (Computed Tomography): a detailed imaging test that allows doctors to examine internal organs and detect abnormalities in different parts of the body. It is often performed with a contrast agent injected into a vein and helps measure the size and extent of the disease.

MRI (Magnetic Resonance Imaging): not routinely used for all lymphoma cases, but particularly helpful in specific situations, such as evaluating the central nervous system or bones. It does not use ionizing radiation and may be preferred in children or during pregnancy.

PET/CT scan: this combined imaging technique helps identify areas where lymphoma is active. It involves injecting a small amount of radioactive glucose, which accumulates in lymphoma cells. PET/CT is especially useful in certain types of lymphoma, such as Hodgkin lymphoma and diffuse large B-cell lymphoma, and helps assess response to treatment.

Lymph node biopsy

A lymph node biopsy involves removing all or part of a lymph node to examine it under a microscope and determine whether lymphoma is present and which type it is.

If the lymph node is easily accessible, the procedure is usually performed under local anesthesia.

If it is located deeper in the body (such as in the chest or abdomen), surgery under general anesthesia may be required.

In some cases, less invasive needle biopsy techniques guided by CT scans can be used.

If lymphoma is confirmed, further tests are needed to understand how far the disease has spread (this process is called staging).

Because identifying the exact subtype of lymphoma is crucial for treatment decisions, it is important that the diagnosis is carried out in specialized pathology laboratories with proven expertise.

Bone marrow tests and blood tests

To understand whether lymphoma involves the bone marrow, doctors may perform:

Bone marrow aspiration: a small amount of bone marrow is taken, usually from the back of the hip bone, using a needle under local anesthesia. The procedure takes about 15–20 minutes and may cause brief discomfort. Patients can usually return to normal activities the same day.

Bone marrow biopsy: similar to aspiration, but a small core of bone tissue is collected for more detailed analysis

Blood tests: a routine blood sample provides important information about overall health and helps evaluate organ function (such as liver and kidneys) and markers related to lymphoma activity.