LYMPHOMA ISN'T YOUR typical cancer. There isn't always a large tumor growing on an organ such as in breast or prostate cancer. Lymphoma affects the cells in the blood and lymphatic system. It attacks lymphocytes (a type of white blood cell) and causes a malignancy, resulting in tumors in the lymphoid tissue. There are many different types of lymphomas, so diagnosis and treatment can be complicated.
In order to understand what non-Hodgkin's lymphoma (NHL) is and how it affects the body, it's helpful to have an understanding of how the lymphatic system works. Let's review.
The lymphatic system
The lymphatic system plays three major roles in the body.
* Its most well-known function is defense against invading microorganisms and disease.
* It returns excess interstitial fluid to the blood.
* It aids in absorption of fats and soluble vitamins from the digestive system and their subsequent transport to the venous circulation.
The lymph system is divided into two organ groups. The primary group includes the bone marrow, where lymphocytes originate, and the thymus gland, where specific lymphocytes called T cells mature. Lymphocytes that mature in the bone marrow are called B cells. All blood cells arise from the bone marrow where they begin as stem cells; there they eventually replicate and differentiate into different types, including lymphocytes.
The secondary group of the lymphatic system is made up of lymphoid tissue and vessels through which mature lymphocytes travel to protect the body from foreign invaders such as bacteria, viruses, and fungi.
The main stations for circulation of lymphocytes throughout the body include the spleen and lymph nodes, which are located in several areas. Microscopic lymphatic vessels branch off from larger vessels, connecting to bean-shaped nodes in the axillary, inguinal (see The lymphatic system of the body) and cervical (see The lymphatic system of the head and neck) regions. Lymph, or extracellular fluid containing antigens and lymphatic cells, flows through the lymphatic vessels.
Lymphocytes circulating in this system undergo numerous genetic changes to perform defensive roles in the immune system. Generally, B cells recognize and help produce specific antibodies against attacking antigens; T cells help produce cytokines, which kill infected or mutated cells and regulate the body's immune responses. Lymphomas can affect any one of these cells, and diagnosing which cell is affected is essential in determining the patient's treatment plan and prognosis.
Lymphoma: malignant lymphocytes
Lymphomas occur when ordinary lymphocytes undergo malignant change and produce tumors in lymphoid tissue. This process occurs when healthy lymphocytes begin an unregulated growth due to genetic changes or mutations. These mutations interfere with normal cell growth and function.
Lymphomas are classified as either Hodgkin's disease or NHL. When a biopsy shows the presence of giant cells with one or two large nuclei (Reed-Sternberg cells), the diagnosis is Hodgkin's disease. When it shows infiltration of malignant B cells or T cells in the lymph system, the diagnosis is NHL.
Many types of NHL
About 30 different types of NHL exist. Diagnosis depends not only on how the cells look under a microscope but also on how they behave. Diffuse large B-cell lymphoma (DLBCL) is one of the most common forms of NHL, accounting for about one-third of all lymphomas.
NHL attacks the B cells in lymph nodes and bone marrow. Researchers have found that afflicted B cells have certain DNA variants, and the nuclei are twice as large as their normal-sized neighbors. In about 30% of DLBCL cases, genetic mutations of a specific chromosome, BCL-6, are seen that result in an abnormal production of a protein that triggers cell growth.
The cause of most NHLs is unknown. The risk of getting the disease increases with age, and men are more likely than women to contract NHL. Immunodeficiency is linked to an increased risk as well, whether it's acquired, inherited, or from an organ transplant. Certain infections also appear to increase the risk, such as AIDS or an infection with the bacterium Helicobacter pylori.
Aggressive or indolent
NHL spreads through the lymphatic circulation and is classified as either aggressive or indolent.
Aggressive NHL is fast growing, so patients are usually sicker at diagnosis. It's classified as intermediate or high-grade. Because it's usually discovered in the early stages, a cure is more likely.
Indolent NHL is also known as low-grade NHL. Slow growing, it advances further before discovery, making early diagnosis and cure more difficult. Some types of advanced indolent NHLs can be treated immediately or just undergo watchful waiting. The earlier the stage at the time of treatment and diagnosis, the better the cure rate.
Signs and symptoms
Common signs and symptoms of NHL include enlarged lymph nodes, fatigue, weight loss, fever, itching, bone or chest pain, coughing or trouble breathing, and night sweats. About one-third of patients with aggressive NHL have these symptoms. The most common sign of NHL is one or more enlarged lymph nodes in the neck. If the healthcare provider suspects the patient may have NHL, a thorough medical history and blood tests will be completed.
Diagnosis and staging
Once the healthcare provider has determined that the patient's enlarged lymph node or other symptoms aren't caused by something like an infection, a more invasive procedure is necessary to determine a diagnosis. Usually, this entails a biopsy of the lymph node, bone marrow, or involved organ, such as the spleen.
The healthcare provider can perform the biopsy with the patient under local anesthesia. Once cells are extracted, they're sent for a cytology exam to determine whether they're malignant; the report will also indicate the size, type, and even the aggressiveness of the lymphoma. The cells also undergo immunophenotyping (classifying the cells as B or T cells) to further classify the lymphoma.
Besides the biopsy, other diagnostic tests such as complete blood cell (CBC) count, X-ray, magnetic resonance imaging, computed tomography, and positron emission tomography are used to help stage NHL. The staging process helps identify which treatments the oncologist will choose for the patient as well as determine prognostic factors (see Staging NHL).
Once NHL is diagnosed and staged, you'll play an important role in educating your patient. She'll be anxious about her illness and will need information about the disease, the treatments she'll undergo, and any adverse reactions the treatments may cause. Not only will you need to expand on what the healthcare provider has explained, but you'll also refer her to any outside services such as online or local support groups.
Treating NHL
The earlier a patient is diagnosed and treated for NHL, the better her chances of survival. She may receive radiation, chemotherapy, or both, depending on the disease type and stage. The standard treatment for intermediate-grade NHL is R-CHOP chemotherapy (rituximab, cyclophosphamide, hydroxydoxorubicin, Oncovin, and prednisone), which cures about 40% of patients treated. This aggressive regimen kills cancerous cells at various stages in their reproduction cycles.
The patient may also receive chemotherapy alone if she has only a partial response to R-CHOP chemotherapy or to prevent a recurrence.
When used in addition to chemotherapy regimens, radiation can be equally effective with fewer adverse reactions than an increased number of chemotherapy cycles. However, very few cases of NHL are treated solely with radiation, mostly due to the widespread nature of the disease and because radiation can't target lymphoma cells circulating in the body.
The goal of NHL treatment is most often to cure, but some patients have a recurrence after treatment. High-dose chemotherapy with autologous stem cell transplantation (ASCT) is a treatment option for a patient with a relapse. The patient, after receiving high-dose chemotherapy that destroys her bone marrow cell supply, receives a transplant of these cells, which are harvested before chemotherapy, to rescue the bone marrow.
Relapses may occur within the first 2 to 3 years after the NHL diagnosis. During this time, the oncologist will discuss further treatment options, which likely include more chemotherapy, ASCT, or clinical trials.
After a patient has been disease-free for 4 or more years, NHL rarely recurs. However, she must continue to be monitored because secondary cancers may result from the cancer treatment.
Nursing considerations
When your patient is undergoing aggressive treatment for NHL, you'll play a key role in educating her and her family about the disease, monitoring her for adverse reactions, and helping manage her symptoms. The most common issues a patient may face while undergoing treatment for NHL include:
* myelosupression. This common adverse reaction results in the destruction and decreased production of stem cells. A low red blood cell count (anemia) means less oxygen-carrying ability, and the patient may experience shortness of breath and tachycardia. A low white blood cell count (neutropenia) means less protection against infection, and the patient may experience fever, chills, and painful or frequent urination. A low platelet count (thrombocytopenia) means less clotting capabilities, and the patient may experience bloody urine, black stools, excessive bruising, and cuts that stop bleeding only with applied pressure. Monitor your patient's CBC count before each treatment and administer packed red blood cells as ordered. Monitor her temperature daily and assess her for signs and symptoms of infection. Call the healthcare provider if her temperature exceeds 100.5[degrees] F (38[degrees] C).
* nausea and vomiting. Common after chemotherapy, these reactions are often preventable and treatable with antiemetics before and after treatment. A combination of antiemetics with steroids and antianxiety drugs, such as ondansetron (Zofran) or granisetron (Kytril), is often used.
* mucositis. Mouth sores often develop as chemotherapy and radiation destroy epithelial cells in the oral mucosa. Fungal infections may develop in the mouth and can be so severe that the patient can't eat, speak, or swallow. Baking soda and saline rinses every 6 hours can help reduce the severity of mucositis.
* alopecia. The patient's hair commonly falls out 10 to 14 days after starting chemotherapy. It usually grows back after treatment but the texture or color may be different. Provide your patient with resources such as cancer organizations and support groups so she can receive wigs or scarves, if she requests them, before or early on in treatment. Related skin changes or nail changes may occur as well, so encourage your patient to moisturize her skin regularly and use sunscreen.
* fatigue. Treatment for NHL can be incredibly tiring, so encourage your patient to pace her daily activities by taking frequent breaks. The fatigue may be severe and require physical therapy consultations. Recommend mild-to-moderate exercise, such as walking. Fatigue may be associated with a loss of appetite or feeling hungry; encourage your patient to eat frequent small, high-protein and high-calorie meals throughout the day and to drink plenty of fluids. Advise her not to eat right before treatment.
* cardiotoxicity. Chemotherapy can cause damage to the heart muscle; monitor your patient with an ECG to determine adequate left ventricular ejection fraction before her first chemotherapy treatment. Watch for signs and symptoms of heart failure, including dyspnea on exertion, orthopnea, paroxysmal noctural dyspnea, and fatigue.
* hyperglycemia. Prednisone can elevate blood glucose levels; if your patient has diabetes, her treatment regimen may need to be altered.
* fertility. Treatment for NHL can lead to sterility, so sperm banking is usually offered to men before treatment. Because chemotherapy and radiation can cause birth defects in a fetus, patients must use birth control during treatment. Provide options and support, especially to young adults.
* infusion reactions. Common during chemotherapy, infusion reactions may be reduced or less severe if the patient is premedicated with antihistamines, steroids, or acetaminophen. Visually monitor her vital signs and look for signs and symptoms of a reaction (flushing, rash, back pain, anaphylaxis). Stop the infusion immediately and notify the healthcare provider if a reaction occurs.
Most of these adverse reactions related to the treatment of NHL are manageable and resolve after treatment. It's important that your patient and her family understand what's happening to her, what adverse reactions are considered normal, and what signs or symptoms are emergencies for which they need to immediately alert the healthcare provider.
Provide support
Many treatment options are available to a patient diagnosed with NHL, and she'll be feeling scared and overwhelmed. The first step in effectively educating your patient is educating yourself. Keep up to date on current treatments and cancer management, as they're always evolving. Knowing how to best help your patient fight this disease will have a positive impact on her experience and her ability to manage it.
Staging NHL
Stage I
Limited to one node or region of nodes
Stage II
Present in two or more regions; both regions are located either above or below the diaphragm
Stage III
Extends to either side of the diaphragm and may or may not include nearby organ involvement
Stage IV
Has spread to an organ not located near nodal involvement or extends to bone, liver, brain, spinal cord, or pleura (of the lung)
On the Web
The American Cancer Society: http://www.cancer.org
Leukemia & Lymphoma Society: http://www.leukemia-lymphoma.org
Lymphoma Information Network: http://www.lymphomainfo.net
Gilda's Club: http://www.GildasClub.org
Selected references