What is lymphoma?
To understand what a lymphoma is, we need to know what lymph nodes are. Lymph nodes are small, grape-sized structures that are present in various locations on the body. They are a part of an organ system called the lymphatic system. This involves lymphatic organs and vessels and lymph nodes. They form a vital part of our immune system. The organs that are a part of this system are spleen, thymus, lymph nodes, lymphatic vessels.
The cancer associated with lymphatic system is called lymphoma.
There are two types of lymphoma:
- Non-Hodgkin’s lymphoma
- Hodgkin’s lymphoma.
What is Hodgkin’s lymphoma?
It is a type of cancer of the lymphatic system that involves the lymphocytes. It is the lesser common type of the two and commonly affects individuals within the age group of 20 to 40.
Hodgkin’s lymphoma spreads though lymph nodes more commonly and frequently affect the upper section of the human body. It rarely spreads through blood or local invasion.
What are the types of Hodgkin’s lymphoma?
Based on their structure and intensity of spread, they are further classified:
- Classical Hodgkin’s lymphoma:
It is the most common type which accounts for over 95% of the cases. This form of lymphoma affects the B lymphocytes and produce an abnormal type of cell called the Reed-Sternberg cells. This type has four subtypes:
- Nodular sclerosing HL: it is the most common subtype. It presents with Reed-Sternberg cells with reactive eosinophils, lymphocytes and plasma cells. It also shows varying degrees of sclerosis.
- Mixed cellularity HL: it contains numerous Reed-Sternberg cells and inflammatory cells which include eosinophils, lymphocytes, and plasma cells. There is no sclerosis involved.
- Lymphocyte rich: this type is rare and shows many features. It is often confused with a subtype of non-Hodgkin’s lymphoma. It also has the best prognosis of them all.
- Lymphocyte depleted: this is again a rare form of HL. It shows pleomorphic (structurally different) Reed-Sternberg cells. It may be easily confused with diffuse large cell lymphoma.
- Nodular lymphocyte predominant Hodgkin’s lymphoma:
These are a much rarer form of HL. They account for around 5% of the cases. They contain distinct variants of Reed-Sternberg cells called popcorn cells.
What are the risk factors for causing Hodgkin’s lymphoma?
There are a few factors which are said to increase the risk of HL:
- Epstein Barr virus infection: infectious mononucleosis is an infectious disease caused by Epstein Barr virus. It slightly increases the risk of developing Hodgkin’s Lymphoma. Sometimes, even parts of the virus may be present in the Reed-Sternberg cells.
- Age: people in their late 20s to 40s and post 55 years are more prone to Hodgkin’s Lymphoma.
- Sex: Hodgkin’s Lymphoma is more common in males than females.
- Region: it is more common in the United States, Canada, and Europe and least common in African and Asian countries.
- Family history: patients with siblings who are confirmed to be affected by Hodgkin’s lymphoma are at a higher risk, especially in twins, where one is confirmed to be affected.
- Socioeconomic status: research says that people having higher socioeconomic status tend to have an increased risk of contracting HL.
- HIV infection: the patients who are immuno-compromised also develop HA much easier than patients who are not affected.
What are the causes for HL?
It is believed that once the patient contracts the Epstein Barr virus, there are changes in the DNA of the B lymphocytes. This leads to formation of Reed-Sternberg cells which are the cancer- causing cells.
Reed-Sternberg cells further stimulate the cytokines which attract other lymphocytic cells and enlarge them. This in turn feeds the Reed-Sternberg cells.
What are the signs and symptoms of HL?
- Night sweats
- Weight loss
- Loss of appetite
- Itchy skin
- Loss of appetite
OTHER NON-SPECIFIC SYMPTOMS:
- Lumps: lumps or swellings are seen in regions where lymph nodes are usually present. The most common site it the neck. It is usually painless but does show symptoms of pain on consumption of alcohol (in about 5% of the cases). The lymph node enlargement due to infections go back to their normal size within a week or two and show extreme tenderness to touch. On the other hand, lymphomas do not reduce in size, but may increase in size and usually do not pain.
- Cough and difficulty in breathing: the lymph nodes present in the throat and chest region may swell up and impinge on the trachea. This may cause cough and make breathing difficult. It may even cause chest pain.
- Splenomegaly: enlargement of the spleen may be seen in some of the patients.
- Hepatomegaly: enlargement of the liver may also be notices although uncommon. A combination of both spleen and liver may also be seen which is called hepatosplenomegaly.
- Red bleed spots, petechiae, bruises: due to bone marrow infiltration, the number of platelets are reduced leading to bleeding through capillaries and blood vessels.
- Nephrotic syndrome: it is a disorder which involves the failure of the kidneys. It may be seen in some cases of lymphoma.
How do we detect Hodgkin’s lymphoma?
Being aware of the early symptoms and suspicious features can aid in early detection and screening of HL.
If any long-standing, multiple lymph node swellings are noted, unexplained weight loss, persistent fever, severe and constant itching of the lymph node after drinking alcohol are some symptoms which should not be ignored.
- Biopsies: biopsies are a small section of the tissue which is to be sampled. The tissue is removed from the swelling and fixed. It is sent to the histopathology labs for reports. There are two types of biopsies: incision biopsy and excision biopsy.
Incision biopsy: one in which the entire swelling is not removed but a small section is removed.
Excision biopsy: one in which the complete lymph node is removed and sent for biopsy.
It can be done under local anaesthesia or general anaesthesia if the swelling is located in deep structures.
- Needle biopsy: instead of making a cut on the skin, a needle bore is used to get a sample of the tissues and biopsy it. This again has two types: fine needle aspiration cytology and core needle biopsy.
Fine needle aspiration cytology (FNAC): is used to withdraw fluids into a syringe barrel which is then sent for cytology.
Core needle biopsy: it is one in which a larger needle is used to remove a larger piece of tissue.
- Bone marrow biopsy: it is similar to needle biopsy, but the sample taken out is bone marrow. It is done to see if the lymphoma has spread to the bone marrow.
- Imaging: x-rays, CT scans, MRI, PET scans, and bone scans may be used.
Chest X-rays: the Hodgkin’s lymphoma can be detected on an X-ray
C T scans (computer tomography scans): they give a better view of the swellings and are useful to detect swellings in the neck, chest, abdomen and pelvis.
They may be used to guide the needle for FNAC.
PET scans (positron emission tomography): a radioactive form of sugar which accumulates in the cancer cells.
- Blood tests: complete blood count: an estimate of the blood cells is measured to check for deficiencies in the blood components, erythrocyte sedimentation rate, and even liver and kidney function.
- Heart and lung function tests: these may be performed if the medications given have a harmful effect on those with heart and lung conditions.
After diagnosis, the lymphoma is grouped into stages for better management and treatment.
What are the methods of treatment used for Hodgkin’s lymphoma?
The treatment modalities for Hodgkin’s lymphoma are:
There are various regimes for treatment:
- MOPP: this involves using four drugs- Mustargen, Oncovin, Prednisolone, Procarbazine. The treatment is done in four-week cycles, for six cycles. This treatment is currently used for relapse cases.
- ABVD: this involves the following drugs – Adriamycin, Bleomycin, Vinblastine, Dacarbazine. This treatment usually lasts from six to eight months.
- Stanford V: this treatment regime involves the same drugs as ABVD but it is more intensive and also includes radiation therapy.
- BEACOPP: this regime involves Doxorubicin, Bleomycin, Vincristine, Procarbazine, Cyclophosphamide, Etoposide, Prednisolone. It is used in lymphomas which are above the second stage. It is believed to have a mild chance of causing secondary leukaemia. It shows a success rate which is 15% higher than ABVD.
Radiation therapy: radiations of electron field and X rays are given through a type of therapy called external beam radiation therapy. It is usually combined with radiotherapy and is given for 30 minutes per dose.
What is the success rate of the treatment?
In a recent study, it was seen that a five-year survival rate for the patients with favourable prognosis was 98% and for those with worse prognosis was at least 85%.
The factors that indicate a poor prognosis are:
- People over the age of 45
- Stage 4 disease
- Haemoglobin less than 10.5 g/dl
- Lymphocytic count less than 8%
- Albumin less than 4g/dl
- White blood count more than 15,000/microliter