Hodgkin’s Lymphoma is one of the most curable malignancies. It typically presents mainly in the 20s age group, and then again in the 50s.
There are no obvious risk factors, but there are associations in sibling family members. This suggests a common exposure to an infectious or environmental agent during the early years. Epstein-Barr Virus genetic material has been found in Hodgkin’s tumor tissue.
Diagnosis: requires a biopsy of the involved lymph nodes. Sometimes, multiple biopsies are required, to detect the abnormal cells in the milieu of the normal fibrous tissue, blood vessels and the variety of normal lymphoid cells.
The Reed-Sternberg cell is required for diagnosis of Hodgkin’s lymphoma. It has a typical appearance, but sometimes hard to find. Special stains and genetic tests on the tumor tissue can help identify the R-S cell.
Signs and Symptoms: Commonly, the disease presents with involvement of lymph nodes above the diaphragm. These can be detected with swollen lymph glands in the neck and armpit. Additionally, the patient can experience night sweats, unexplained fevers, weight loss, and itching, also called” B symptoms”.
Staging: Is done by
-Counting the number of involved sites, 1-4, going from one site to extensive.
-Whether the disease is present on both sides of the diaphragm
-If the disease is bulky, particularly in the center of the chest
-If the lymphoma involves the adjacent extra-nodal tissue, e.g. the spleen, liver, or bone marrow
-If B symptoms are present.
The required investigations include CT scans, and a PET scan (which has eliminated the need for a splenectomy). A bone marrow biopsy is recommended, particularly if the disease is considered to be an early stage, and limited treatment is being considered. Bone marrow involvement would upstage the disease, and limited treatment would then not be adequate treatment.
Blood tests will include a Complete Blood Count (CBC), Alkaline phosphatase, LDH and ESR (which are markers of disease activity), and baseline liver and kidney function tests.
Different histological subtypes: depend on the proportion of the components of the lymph gland: Nodular sclerosis is the most common type, followed by mixed cellularity, Lymphocyte predominant is less common, if often localized, and can be treated with radiation alone. Lymphocyte depleted is rare, usually presents in an advanced stage, and has an aggressive clinical course.
Treatment: depends on Stage, presence of bulky disease, and B symptoms.
Radiation therapy of the involved field alone is feasible for limited stage, non-bulky disease, with good features
Chemotherapy in combination with radiation therapy is the most common approach for intermediate stage, or bulky disease. The number of chemotherapy treatments required is evolving, with the goal of maximizing cure and minimizing long-term toxicity. Recent trials have shown benefit of decreasing radiation fields by delivering 2-4 cycles of chemotherapy up front.
Chemotherapy alone is recommended for disease on both sides of the diaphragm, and Stage 4 disease.
Disease response is measured during treatment with serial blood work and CT scans.
Salvage chemotherapy is available for relapses. If there has been a long disease free interval, they may be treated with standard doses. If the relapse is within 1 year, high dose chemotherapy will be required. If there has been no response, high dose chemotherapy with bone marrow transplantation may be required.
The most common first line chemotherapy combination is Adriamycin, Bleomycin, Vinblastine and Dacarbazine: ABVD. This is infused 2 days of every month, on Day 1 and Day 15. This cycle is repeated every 28 days for the prescribed duration. Other chemotherapy combinations have not yet shown better results with less toxicity.
Toxicity: our goal is to minimize toxicity while maximizing cure, given the young age at presentation, and expectation of a long life span.
Long term Radiation related toxicity:
Unfortunately, since the areas of involved lymph nodes are usually in the neck, chest or groin, the surrounding vital tissue (thyroid, heart, breast tissue, ovarian and testicular tissue) is vulnerable to radiation toxicity. This can result in
-Hypothyroidism
-Inflammation of the heart and lung linings, or coronary artery disease
-2nd malignancies: e.g. Breast Cancer and Lung Cancer
-Infertility
Long term Chemotherapy toxicity: is related to the individual drugs being used.
-Adriamycin can cause cardiomyopathy, though rarely at the doses used for initial therapy. Retreatment is a bigger problem
-Bleomycin can cause lung toxicity. This is monitored with lung function tests with each cycle of treatment, and the drug is dropped if they worsen.
-Infertility or premature menopause
-2nd malignancies are seen 15 years later
-Myelodysplasia (bone marrow malfunction) and acute leukemia can been seen between