Hodgkin lymphoma

Hodgkin lymphoma is a group of malignant neoplasms of lymphocytes (usually B) and, less frequently, histiocytes.

They represent 2-3% of all tumors (their frequency is higher than that of Hodgkin’s disease) and they are more common in men; they have a peak of incidence between 20 and 40 years (they are the most frequent neoplasms at this age).

Causes of Hodgkin lymphoma

The various studies carried out have shown the correspondence of Hodgkin’s lymphomas with various etiologies, such as:

• Viral infections, Epstein-Barr virus (related to Burkitt lymphoma, a type of non-Hodgkin lymphoma), HTLV-1 virus (adult T-cell leukemia-lymphoma virus).
• Helicobacter pylori infection (bacteria related to gastritis and stomach cancer ).
• Previous immune deficiency (due to AIDS , transplants, etc.).
• Previous chemotherapy or radiation therapy .

In some non-Hodgkin lymphomas (Burkitt, centrocytic, follicular) there are characteristic genetic alterations.

The cells of the immune system that, due to the factors listed above, have become malignant proliferate uncontrollably in the lymph nodes and the rest of the lymphatic tissue, causing tumors and subsequently infiltrating (to a greater or lesser degree, depending on their aggressiveness), other tissues. .

As we have just said, there is variability in terms of the aggressive capacity of the different lymphomas, a fact on which the different classifications of these tumors are based:

Job classification

Low-grade lymphomas

• Small cell lymphocytic.
• Follicular, with a predominance of small cleft cells.
• Mixed follicular, with small and large cleft cells.

Intermediate grade lymphomas

• Follicular with a predominance of large cells.
• Small cleft cell diffuse.
• Small and large cell mixed diffuse.
• Large cell diffuse.

Highly aggressive lymphomas

• Immunoblastic large cell lymphoma.
• Lymphoblastic
• Small cell non-cleft lymphoma (Burkitt’s lymphoma).

Rappaport classification

• Lymphocyte lymphomas (corresponding to the small cells of the previous classification), which can be: well differentiated or poorly differentiated.
• Histiocyte (large cell) lymphomas.
• Mixed lymphocytic-histiocytic lymphomas (small and large cells).
• Undifferentiated lymphomas (variety including the Burkitt type).

Kiel or European classification

Low aggressive lymphomas

• Lymphocytic lymphoma or chronic lymphocytic leukemia.
• Lymphoplasmacytic lymphoma or immunocytoma.
• Centrocytic lymphoma (corresponding to the cleaved cells of the Working classification). ˇ Centrocytic-centroblastic lymphoma (the centrocytes corresponding to the cleft cells of the Job classification, and the centroblasts to the large cells of said classification and to the histiocytes of the Rappaport classification) or follicular.

Highly aggressive lymphomas

• Centroblastic lymphoma (large cells or histiocytes).
• Lymphoblastic lymphoma (Burkitt or non-Burkitt type). ˇImmunoblastic lymphoma (the immunoblast corresponds to large cells and histiocytes).

Actual classification

Very similar to the previous ones, adding to the low aggressive lymphomas the large granular cell lymphocytic leukemia and the marginal zone lymphomas (which include those associated with mucosa), and to the highly aggressive lymphomas the angioimmunoblastic and anaplastic large cell lymphomas.

Symptoms of Hodgkin lymphoma

In the case of low aggressive lymphomas, the multiplication and development of the tumor are slow, with prolonged symptoms and few symptoms at the beginning, which means that, usually, at the time of diagnosis, the disease is already present. advanced. Unfortunately, the fact that cell duplication is not rapid leads to a lower response to chemotherapy, making it difficult to achieve complete cure.

Highly aggressive lymphomas proliferate very rapidly, with a short course with accelerated growth of lymphadenopathy, abundant metastases in different organs and a short course. Paradoxically, the fact that they multiply quickly allows a complete cure to be achieved in 80% of cases when the patient undergoes treatment, although, as is logical due to their high aggressiveness, they have a poor prognosis if chemotherapy is not applied.

Extranodal involvement occurs with great frequency (especially in Waldeyer’s lymphatic ring -located in the throat-, the digestive tract, the skeleton, the skin, the lungs, etc.).

In these, the clinical manifestations vary according to the location. Thus, a feeling of occupation or obstruction, pain, abdominal discomfort, bleeding or intestinal obstruction may appear (especially in children), nodules on the skin … They are also very frequent: presence of paraprotein, as well as malignant cells in the blood (leukemia ), painless peripheral lymphadenopathy and liver involvement without spleen damage.

The listed symptoms appear more frequently in this type of lymphoma than in Hodgkin’s disease, although the following are more common in the latter: B symptoms (that is, fever , night sweats, and unexplained weight loss greater than 10% in patients). last 6 months), mediastinal involvement and localized disease.

How is it diagnosed?

After carrying out the clinical history and physical examination, emphasizing the latter in areas such as Waldeyer’s ring, we will perform the fundamental test for the diagnosis of this disease, the lymph node biopsy.

This will also allow us to obtain the histological type of the lymphoma, according to the classifications previously outlined, which is essential for the prognosis of the tumor.

Laboratory tests, such as blood tests (to check, among other things, for anemia), liver and kidney function tests, checking for genetic abnormalities, biochemical analysis, and protein electrophoresis will be of great help. serum to detect the presence or absence of the paraprotein.

Chest x-rays and chest computed tomography (CT), in addition to diagnosis, will be useful for tumor staging.

The staging method known as the Ann Arbor classification was created for Hodgkin’s disease, and it is not widely applicable to Hodgkin’s lymphomas; It is simply convenient to know that stages I and II refer to the fact that the process is located on one side of the diaphragm (better prognosis), III means that both sides are affected and IV, that there is already extranodal extension, especially in the medulla bone and liver (infiltration of these two organs will be demonstrated by doing the biopsy as well).

Other tests, also useful (depending on the case) in the study of the extension of this disease, are abdominal CT, lumbar puncture , study with barium contrast of the digestive tract and gallium scintigraphy.

Surgical staging with tests such as laparotomy is less and less used.

The differential diagnosis must be considered, fundamentally, with Hodgkin’s disease, although it can also be done with certain solid tumors, such as some types of lung cancer.

Hodgkin lymphoma treatment

We must differentiate between the treatment of low aggressive lymphomas and those of high aggressiveness. Thus, currently in the case of the former, polychemotherapy (sometimes interferon alfa or fludarabine) and bone marrow autotransplantation are used, while in the latter, aggressive polychemotherapy cycles are indicated, such as CHOP (which consists of the association of cyclophosphamide , vincristine, prednisone and doxorubicin) or its combination with other agents (bleomycin, nitrogen mustard, cytosine arabinoside, etc.), resorting to bone marrow transplantation in patients who do not respond.

In the case of gastric lymphomas associated with infection by the Helicobacter pylori bacterium, treatment consists of eliminating this microorganism by combining the drugs omeprazole, clarithromycin, and amoxicillin .

The prognosis of the disease will depend, as we have already said, mainly on the histological type (unlike Hodgkin’s disease in which the most important factor is the tumor stage).

In general, patients with low-grade lymphomas respond worse to chemotherapy.

It should also be noted that the presence of certain factors, such as the advanced age of the patient, other associated diseases (such as AIDS), poor general condition or the existence of B symptoms, worsens the prognosis.

How can I avoid it?

Unfortunately there is no effective way to prevent this disease.

The family doctor should be consulted in the prolonged presence of any of the mentioned symptoms; for example, sensation of obstruction in the throat, digestive discomfort, lumps in different regions of the body …