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Bone marrow transplantation questions & answers.

Introduction

During the last decade, bone marrow transplantation has evolved from a last-resort, desperate experiment to a well-established treatment option for a variety of life-threatening diseases.

In 1977, a total of 169 patients received bone marrow transplants worldwide; by 1993, 10,000 patients had received transplants carried out in more than 250 centers in 40 countries. Currently, patients with leukemia, lymphoma, advanced or resistant solid tumors, severe aplastic anemia and selected immune deficiency disorders and genetic errors now have another possible treatment that offers meaningful chances for cure.

As a direct result of the burgeoning interest and treatment possibilities in the field of bone marrow transplantation, the Leukemia Society of America has developed this brochure to explain the procedure and many related questions.

Q. What is "Bone Marrow Transplantation"?

A. bone marrow "transplant" (BMT) is best viewed not as a surgical procedure or operation, but as a transfusion of marrow, not blood, from one individual to another or to the same individual. Bone marrow is the spongy tissue inside bones which manufactures various components of blood and the immune system: red blood cells, white blood cells and platelets. Each of these different cells has a vital role to perform in keeping the body healthy and free of disease.

In the case of leukemia, the white blood cells are the usual malignant target. Since restraints on their growth are lost, leukemic white blood cells usually overproduce. Such overproduction hinders the process of normal blood cell development in the bone marrow. Thus, there is:

1. decreased red blood cell production leading to anemia.

2. decreased platelet production leading to bleeding either internally, externally or into the skin (bruises and purpura).

3. decreased production of normal white blood cells, leads to greater risk of infections. If untreated, leukemia can lead to progressive disease and death.

Chemotherapeutic agents (drugs and other biological material) can destroy these malignant cells, but are destructive to the normal marrow cells as well. Standard treatments for leukemia usually limit the drug dosages so they are not too damaging to the bone marrow and elsewhere. Very large doses of drugs are given during a bone marrow transplant to potentially eradicate the disease. The patient's bone marrow is restored to grow as "normal", with balanced production of all blood cell components. Transplantation takes place after chemotherapy, radiation and other treatments have eradicated the malignant cells from the patient's system and have suppressed the patient's immune system, the latter designed to prohibit an intact immune system from rejecting the "foreign" or donor marrow. The patient's bone marrow is then replaced by an infusion of bone marrow from a donor (allogeneic) or from the patient him or herself (autologous).

The transplanted bone marrow cells migrate to the marrow space and actually begin the process of repopulation. When the marrow is successfully accepted (i.e. engrafts) and the leukemic cells do not recur, the patient has a chance for leukemia-free survival leading to cure.

In lymphoma, the cells which make up the lymph node tissue become malignant. In malignant solid tumors, the cells which make up muscle, bone, glands, i.e. all tissues, become malignant. Standard chemotherapy destroys the malignant cells but is also toxic to normal marrow cells, thus limiting the dose of the drugs that can safely be given. Bone marrow transplantation is used to counter the destructive effects of chemotherapy on the normal marrow cells so that massive doses of chemotherapy can be given to eliminate cancer in patients who do not respond to standard drug dosages.

It is also known that following allogeneic transplantation, a subset of the infused cells have a beneficial anti-leukemic effect, which enhances the marrow transplant, per se, by an ongoing onslaught against residual "drug resistant" cancer cells.

Q. When is a bone marrow transplantation indicated as treatment?

A. Bone marrow transplantation is currently considered the treatment of choice for severe aplastic anemia, specific immune deficiency states (e.g., severe combined immune deficiency or SCID), chronic myeloid leukemia (CML) and in a sub-group of patients with acute lymphocytic and nonlymphocytic leukemias who have specific chromosomal markers which are known to predict a poor outcome (e.g., Philadelphia chromosome) or other factors (e.g. high tumor burden at onset). It is also indicated for those patients who have failed standard methods of treatment, primarily chemotherapy and radiation therapy. These include patients with acute lymphocytic leukemia (ALL) in second or subsequent remissions, acute myelogenous leukemia (AML) in second or subsequent remissions, resistant forms of lymphoma, as well as advanced or resistant solid tumors.

Among the considerations that determine transplant eligibility are age (usually, but not always, under 55 years of age), general physical health, condition of specific organs (heart, lungs, liver, etc.), prior chemotherapy treatment and transfusion history. Patients should inquire about the possibilities for bone marrow transplantation soon after diagnosis. Contacts with institutions specializing in bone marrow transplantation are best directed through the patients' physician, who is familiar with the details of personal medical and psychological histories.

Q. Who can act as a donor for a bone marrow transplant?

A. The ideal donor is a tissue-matched family member, usually a sibling. Identical twins are not ideal as donors in the leukemias because of the failure to induce controlled graft-versus-host disease (GVHD) and its attendant anti-leukemic effect. Unfortunately, only one out of every four who need transplantation have genetically matched siblings.

For those who do not have a family donor, other options include autologous or unrelated donor transplants. In the autologous setting, patients act as their own donors. Patients receive back their own marrow, which had been previously removed at an earlier stage of illness or when the disease was in remission. It is then treated, frozen and stored until needed. Sometimes an unrelated donor may be identified through donor bank searches. Matched unrelated donors offer an additional 10 to 15 percent chance for transplantation.

Peripheral blood also contains marrow-like stem cells. A technique, called peripheral stem cell pheresis, is performed after priming the patients bone marrow with substances known as growth factors during a critical period after certain chemotherapy courses. The "turned on" bone marrow "spills" some of its cells into the peripheral bloodstream that can then be collected and isolated. Because the ratio of the stem cells in the bloodstream is generally about 10 percent of those in the marrow itself, usually three or four phereses are needed to obtain a proper number of engraftable cells.

Q. How is the bone marrow "treated" to rid

it of unwanted cells?

A. Once the marrow cells are aspirated, treatment in the laboratory with specific agents is carried out in the following situations:

1. If the source of the bone marrow is the patient and if the cancer has already involved the bone marrow, the contaminating malignant cells can be removed (i.e. purged) using special advanced techniques. These may involve the use of either chemotherapy agents in the laboratory (e.g. vincristine, dexamethasone, etc.) or of microspheres attached to markers called monoclonal antibodies (e.g. cALLA, or "common acute lymphoblastic leukemia antigens"). These markers attract malignant cells. The spheres with the attached malignant cells are then eliminated using magnets. This technique is called immunomagnetic purging. Complement, a natural anti-cancer product, can also be used with the antibodies.

2. If the donor is not a perfect match, graft-versus-host disease (GVHD) is a serious and potentially fatal complication. Under these circumstances, to decrease the incidence and the severity of this complication, the donor bone marrow cells are cleansed of a particular population of cells (known as T cells) that are thought to cause GVHD.

Q. What determines if a donor/recipient "match" will be successful?

A. The body's immune defense system consists of white cells which travel continuously throughout the body in surveillance of foreign substances or cells. They destroy what they perceive as "non-self".

Therefore, when donor bone marrow cells are transplanted into a new host, a spectrum of donor-host interactions occurs. On one end of the spectrum, the recipients immune system may reject the donor's cells (i.e. graft rejection or failure). On the other end, the donor's cells may attack (reject) the recipient's tissues in what is called graft-versus-host reaction.

The closer the match is between the patient and the donor, the less these complications are likely to occur. Preparatory treatments that are currently used before transplantation and which suppress the patient's immune system make graft rejection a rare event. Also, current technology is now able to remove or suppress the T cells which are responsible for GVHD, thus making bone marrow transplants between genetically unmatched individuals possible. However, transplants between genetically matched individuals still have the best chance for success.

Q. How is a potentially successful bone marrow match identified?

A. Bone marrow cells have surface structures which can recognize and reject foreign tissues. These are called human leukocyte antigens or HLAs. Four sets of HLA antigens have so far been identified. A, B, C, D. To insure the best possible acceptance of donor bone marrow, it is best to match all of the four HLA antigen sites. The D-antigen set is closely scrutinized, since it determines the level of immune response and rejection of foreign tissues.

Two blood tests are done to determine how good the match is between donor and patient cells. They are referred to as HLA typing and MLC assay. All that is needed to determine if an individual is a possible donor is a small sample of blood. Donor and patient samples are compared by mixing small samples of white blood cells with small amounts of blood sera positive for specific HLA-A, B, C, and D. If cells are destroyed, this indicates

that the cells carry the particular HLA set being tested. Then, blood cells from the donor are mixed with blood cells from the patient in a radioactive assay. If there is a high amount of cross-reactivity between them, or radioactivity, the donor cells are incompatible despite the apparent match. The blood assay is called MLC, or mixed leukocyte culture assay.

A more sensitive method to detect subtle differences between the HLA typing of both the donor and the recipient is DNA typing. It is far more effective in identifying those patients at risk for development of GVHD.

Q. What is the procedure for donating bone marrow?

A. Marrow is withdrawn (harvested) from the donors hip bone using a special syringe and needle in the operating room under general anesthesia. A bone marrow cell count is performed to determine if the recommended cell dose of 2-6 X [10.sup.8] nucleated cells/kg (200-600 million cell/kg) of patient weight has been achieved. The needle puncture sites may be tender for less than a week and leave essentially no scars. Some mild stiffness and tenderness will last for a day or so, but this discomfort can be lessened through exercise and low dose pain medication. Donors are usually discharged from the hospital the next day.

The relatively small amounts of marrow and blood taken from the donor (based on the volume needed by the recipient which varies from a few ounces to one to two pints) does not result in any bad effects. Marrow cells are quickly produced by the donor and the amount which is removed will be manufactured in two or three weeks. Often, blood is taken before the marrow donation and may be returned to donors to restore their blood volume.

The procedures involved in blood and bone marrow donation are simple, but they still can be new and unsettling experiences. Most centers which specialize in bone marrow transplants are aware of this, and their hospital staff are supportive. They recognize that donors are very special people.

Q. How is the marrow transplant carried out?

A. When the marrow has been taken from the donor (in some cases the patient himself), it is strained through closed plastic filters and containers to remove fat, small pieces of bone and other particles, and to break up large clumps of cells. Sometimes, the marrow is processed further to remove the previously described additional unwanted disease or immune system cells. If patients are their own donors, the marrow is preserved and frozen until the patient needs it. If the bone marrow cells are to be frozen, a protective agent called dimethyl sulfoxide (DMSO) is used to maintain the integrity of the cells in the frozen state. This substance has a strong, garlic-like odor that may be excreted into the patients breath for one to three days. If the marrow is not stored after processing, it is packaged in plastic bags and brought to the patients bedside. Much like a transfusion, the purified marrow enters the patient's bloodstream through an intravenous line. It finds its way to the proper place in the interior of the major bones of the body, "homes" in and begins to produce new and normal blood cells. This process is called engraftment and usually takes two to three weeks. (The exact body mechanisms controlling the homing effect of marrow is not fully understood.)

The infusion of donor bone marrow usually takes about two hours. Marrow recipients suffer no special discomfort from the transplant although an allergic type of reaction may develop: hives, chills and a rapid pulse or heartbeat. Antihistamines, and other allergy medication, are given as a precaution.

Q. How long is it from the time patients enter the hospital until they receive the donated bone marrow?

A. The average time from admission to transplant is about two weeks. Ideally, patients should be in remission from their leukemia in order for a bone marrow transplant to be considered an appropriate treatment. Prior to admission, the patients' disease status and physical condition are evaluated in order to see if they will benefit from such a procedure. A series of tests which are all familiar procedures for cancer patients will take place at this time. They include bone marrow aspiration and biopsy, x-rays, blood tests, tests of heart, liver, lungs and kidney function.

Before admission, patients receive a Hickman or Broviac catheter, a hollow tube much like an intravenous line, placed in between the neck and the shoulder leading into a vein. This special catheter allows blood samples to be taken and medications given without the use of needles and painful injections.

During the first few days after admission, chemotherapy with or without total body radiation is administered in doses large enough to destroy the patients own bone marrow and blood cells as well as the cancer cells. This process is known as "conditioning" and serves three different purposes. 1) it creates space in the bone marrow to allow for the expansion of the new marrow cells, 2) it helps to prevent graft rejection, and 3) it eradicates malignant cells. The infusion of new marrow will rescue the patient from the cell-depleting effects of the chemotherapy and radiation.

Q. What happens after the transplant?

A. Within about two weeks, the transplanted marrow will begin to engraft and to repopulate the patients body with healthy cells. However, not until three to four weeks after the transplant, will a patient's new bone marrow have developed enough to produce sufficient mature cells. Early on, within the first three weeks after transplantation, patients will be given donated blood products as replacement for their developing cells. About six to eight weeks after the actual transplant, patients may leave the hospital if they are able to eat, have no fevers and otherwise are well. Patients are followed for approximately three months, with visits during this time. Many hospitals, through the social work department, assist patients and families in finding living accommodations close to the transplant center.

Three to four months after the transplant, patients may be discharged back to their homes and to their referring physicians. It is not unusual for patients to remain in the hospital longer or to be readmitted for observation or further treatment of infection, or graft-versus-host disease. Patients should not plan to return to work or school for six months after the transplant. Even though blood tests may be normal, the immune system takes that long to recover. Convalescence, both physical and psychological, takes up to one year.

The first two weeks after the transplant are the most physically draining for patients. Many patients develop infections.

Antibiotic and antifungal medications are usually administered in order to prevent infections like pneumonia. Diarrhea and skin rash can be early effects of graft-versus-host disease. Many patients cannot eat much during this time due to the treatment related mouth or gut sores and are given nutrients and fluids through the Hickman catheter.

Patients, staff, and visitors are often required to take some germ-free precautions including antiseptic washing and wearing of a protective mask or sterile garments. Patients are confined to isolation. However, family members and friends may visit and be allowed to help with patients' care during this time.

Q. What is graft-versus-leukemia effect?

A. As previously mentioned, the donor marrow cells contain some active immune cells (T cells) which are responsible for the complication known as GVHD. However, another subgroup is also contained in this population of cells that fights cancer cells and causes the beneficial effect known as "graft-versus-leukemia," or GVL. Scientists are now working on methods to dissect this T cell population into its subgroups. Therefore, the harmful group that causes GVHD can be eliminated or suppressed, while the beneficial group that causes GVL is preserved.

Q. What are growth factors and why are they used?

A. Growth factors are certain substances that are produced in minute quantities in our bodies to stimulate our bone marrow to produce more cells when needed. Investigators have found that when these substances are given to patients with low blood counts, the time period for counts to return to normal is shortened. This also shortens the period during which infectious complications are most likely to occur. Two of the more commonly used factors are termed G-CSF and GM-CSF i.e. granulocyte (type of white cell)-colony stimulating factor and granulocyte-macrophage (another type of white cell)- colony stimulating factor.

Q. What help can patients and families expect from staff of the bone marrow transplant unit?

A. Transplant teams are extensively prepared to support the patient and family throughout the stressful transplantation time. Many centers offer social services and financial advice/planning as soon as an individual is referred to the bone marrow transplant unit as a potential candidate.

Physicians receive extra education to serve on these units. Psychiatrists or psychologists, along with team physicians, provide support for patient, family and donor. Nurses are prepared to care for the special needs of hospitalized bone marrow transplant patients. Social workers, dieticians, pharmacists and physical and occupational therapists are all part of the transplant team and work closely with the physicians and nurses in attending to the transplant patients' social, nutritional and medication needs. Patients and their families should not hesitate to draw upon the expertise and support of the transplant team during all stages of the transplantation and convalescent periods.

Q. Are there any side effects of the bone marrow transplantation procedure?

A. The regimen of total body irradiation and high dose chemotherapy is given to help eradicate leukemia or malignant cells and help prevent graft rejection. High dose radiation usually affects the sexual organs which cannot be shielded because of fear of missing "hiding" leukemia cells. Sterility is a permanent side effect. Bone marrow patients are unable to conceive children. However, sexual function will not be affected. A sperm bank is usually available for male patients who wish to store sperm for future use. Radiation can cause a transient skin rash or burn, nausea, vomiting, swelling of the parotid glands (located near the ears), temporary hair loss and mouth sores. With high dose cytoxan, patients can develop nausea, vomiting, water retention, irritation or bleeding of the bladder, temporary hair loss, and a weakening of the muscles of the heart called cardiomyopathy.

Another common drug used in bone marrow transplantation is called Ara-C. Ara-C interrupts production of blood cells in the bone marrow, and causes nausea, vomiting, loss of appetite, and pain and swelling of tissues lining the esophagus and stomach. When taking this drug, patients may have difficulty in walking and experience photophobia (burning pain in their eyes on looking at light). Their livers may not work normally

Some other drugs used include: VP-16 and busulfan which can bring about a decrease in all blood cell production and which can cause skin darkening, cataracts, hair loss and lung damage. A loss of muscle control (seizure) may also occur during treatment with high dosages of busulfan. This can be prevented by using a drug called dilantin.

Q. What are other possible complications of bone marrow transplantation?

A. Bone marrow transplants are done for high-risk patients. In spite of the great strides made, bone marrow transplantation is still a drastic procedure that may make patients ill and can be fatal. Before a transplant is done, patients' general health, and the condition of certain organs which may have been damaged by earlier treatments, are examined. However, complications may still occur and these include.

1. Infections: Antimicrobial agents are used to prevent certain bacterial, viral and fungal infections. However, due to decreased immunity following transplantation, the patient may still contract an infection which can be serious, and sometimes even fatal.

2. GVHD: As previously described, the donor bone marrow cells can attack the patients tissues, particularly the skin (rashes, pain, itching), gastrointestinal tract (diarrhea, bleeding), or the liver (jaundice and liver dysfunction). As previously mentioned, the bone marrow may be treated in special ways to remove the cells responsible for this complication. In the meantime, medications (e.g. methotrexate, cyclosporin A and corticosteroids) may be used to prevent and/or treat this complication.

3. Veno-occlusive disease: Blood vessels in the liver, kidneys, and less commonly in the lungs may get occluded (blocked). This leads to water retention, increased weight gain and abnormal liver function.

4. Late complications: These may include some hormonal disturbances (e.g. decreased thyroid function, sterility, infertility, sexual dysfunction, etc.), and cataracts, lung damage, second malignancies, and chronic graft-versus-host disease.

Q. How has the Leukemia Society of America supported bone marrow transplantation research? What have been some of the major contributions? What is in store for the future?

A. Since 1955, the Leukemia Society of America has committed approximately five million dollars to pioneer the development of bone marrow transplantation. Bone marrow transplantation has become a standard treatment for aplastic anemia, leukemia and other malignant and genetic diseases.

Use of bone marrow transplantation has increased dramatically in the 1980s. There were fewer than 200 allogeneic transplants worldwide in 1977. In 1992, 10,000 transplants were performed in over 250 centers located in 40 countries. More than 70 percent of the transplants were for leukemia. For this reason, research concerning the best methods of carrying out such treatment must be continued. There are some promising research developments in ways to prevent and to treat graft-versus-host disease which is the single largest complication of bone marrow transplantation. New drugs which control rejection and graft-versus-host disease have also widened the field by allowing the successful transplantation from unrelated donors. More potent chemotherapy drugs, newer methods of administering current drugs, and new schedules, methods and doses of total body irradiation are being investigated so that it becomes easier to destroy the last remaining malignant cells and prevent the disease from recurring. Hopefully, methods will be found to reduce the massive doses of cell killing drugs and total body radiation that are today's only effective treatment. As the function of malignant cells is better understood, transplantation techniques could be greatly refined.

In the future, bone marrow transplants may well be used to treat other diseases of the immune system, such as lupus erythematosus and arthritis. Transplants have already been used to correct genetic abnormalities of the immune system, such as severe combined immunodeficiency disease (SCID), and inborn abnormalities of the blood, such as sickle cell anemia and thalassemia. Exciting research is now being conducted to correct and insert missing genes into bone marrow cells which are then reinfused to correct genetic defects using patients' own bone marrow cells (e.g. sickle cell anemia and fatal enzyme deficiencies).

Q. How can I support marrow donation and transplants?

A. Of the thousands who could benefit from a marrow transplant, nearly 70 percent cannot find a suitable match within their families. These patients need to find unrelated donors - people willing to come to the assistance of someone they likely will never meet. Hundreds, perhaps thousands, of lives could be saved if more people added their names to the list of potential marrow donors.

The requirements to be a marrow donor are few. Unrelated donors must be between 18 and 55 years of age and be able to pass a thorough physical examination, according to the National Marrow Donor Program.

Q. How can I add my name to the list of potential marrow donors or contact a marrow donor registry?

A. There are two registries for unrelated marrow donors in the United States: the National Marrow Donor Program and the American Bone Marrow Donor Registry. The National Marrow Donor Program recruits marrow donor volunteers and maintains a central registry of possible bone marrow donors through their toll-free number 1-800-654-1247. Because this organization represents the largest pool of volunteer donors, it is recommended by the Leukemia Society.

The American Bone Marrow Donor Registry is an association of independent, non-profit donor registries throughout the United States. Individuals wishing to act as marrow donors for this group can call the American Registry at 1-800-7-DONATE. Persons wishing access to the American Bone Marrow Donor Registry on behalf of a patient should contact The Caitlin Raymond International Registry of Bone Marrow Donor Banks at 1-800-7-AMATCH.

Reading in Bone Marrow Transplantation

Non-Technical Books

Mann, Bruce W. Leukemia: A Family's Challenge. Traverse City, Michigan: Prism Publications Inc., 1987.

Thompson, Francesca Morosoni, M.D. Going for the Cure. New York: St. Martins Press, 1989.

Zumwalt, Elmo. My Father, My Son. New York: Macmillan Publishing Company, 1986.

Non-Technical Articles

Schmeck, Harold M. Jr. "Marrow: A Powerful New Tool." New York Times, January 10, 1984.

Stevens, R. "Childhood Bone Marrow Transplantation," Practitioner 1512: 280-285, 1992

Technical Books

Whedon, M. (ed.). Bone Marrow Transplantation: Principles, Practice and Nursing Care. Monterey Ca: Jones and Bartlett Publishers, 1991.

Technical Articles

Armitage, James O. and Gale, Robert Peter. "Bone Marrow Autotransplantation." American Journal of Medicine 86: 203-206, 1989.

Ball, E.D., Rybka, W.B. "Autologous Bone Marrow Transplantation for the Treatment of Adult Acute Leukemia." Hematology Oncology Clinics of North America 7 (#1): 201-231, 1993.

Beatty, P.G. "Results of Alogeneic Bone Marrow Transplantation with Unrelated or Mismatched Donors." Seminars in Oncology 19 (#3, Supplement 7): 7-12, 1992.

Bernstein, S.H. "Growth Factor in the Management of Adult Acute Leukemia." Hematology Oncology Clinics of North America 7 (#1): 255-274, 1993.

Bortin, M.M., Horowitz, M.M., Gale, R.P. et al. "Changing Trends in Allogeneic Bone Marrow Transplantation for Leukemia in the 1980s." Journal of the American Medical Association 268 (#5): 607-612, 1992.

Christiansen, N.P. "Allogeneic Bone Marrow Transplantation for the Treatment of Adult Acute Leukemia." Hematology Oncology Clinics of North America 7 (#1): 177-200, 1993.

Herzig, R.H. "The Role of Autologous Bone Marrow Transplantation in the Treatment of Solid Tumors." Seminars in Oncology 19 (#3, Supplement 7): 7-12, 1992.

Lenarsky, C. and Parkman, R. "Bone Marrow Transplantation for the Treatment of Immune Deficiency States." Bone Marrow Transplantation 6: 361-369, 1990.

Lesko, L. M., "Bone Marrow Transplantation." Psychooncology: the Psychological Care of the Patient with Cancer. New York: Oxford University Press, 1989.

Parr, M.D., Messino, M.J., McIntyre, W. "Allogeneic Bone Marrow Transplantation: Procedures and Complications." American Journal of Hospital Pharmacy 48: 127-137, 1991.

Singer, J.W. "Role of Colony Stimulating Factors in Bone Marrow Transplantation." Seminars in Oncology 19 (#3, Supplement 7): 27-31, 1992.

Thomas, E.D. "Bone Marrow Transplantation: Past Experiences and Future Prospects." Seminars in Oncology 19 (#3, Supplement 7): 3-6, 1992.

Vega, R.A., Franco, C.M., Abdel-Mageed, A.S. and Ragabe, A.H. "Bone Marrow Transplantation in the Treatment of Children with Cancer: Current Status." Hematology Oncology Clinics of North America 1 (#4): 777-800, 1987.

Glossary

blood typing and cross matching

blood cells contain certain factors which can differ from person to person. Before a blood transfusion can be given safely, blood samples from the donor and recipient are typed or classified according to these blood factors (A,B,AB, or O). After typing, the blood samples are cross matched to see if they are compatible. Red cells of the donor are placed in a sample of the recipient's serum and red cells of the recipient in a sample of the donors serum. If the blood does not form clumps, or agglutinate, the two bloods are compatible. Techniques for typing white blood cells and platelets are similar but more complicated.

bone marrow

marrow is the spongy tissue inside the bones which produces many of the elements of the blood.

bone marrow transplant

a procedure in which a patient's bone marrow is destroyed by high doses of chemotherapy or radiation therapy and replaced with new bone marrow from a donor, usually a sibling with HLA typing identical to the patients.

CBC (complete blood count)

a series of tests which examines the various components of the blood, including white cells, red cell and platelets. The tests help determine a patient's general condition and the results of treatments, including regeneration of the bone marrow after transplant.

chemotherapy

treatment with drugs that combat malignant disease. Usually, a combination of several drugs is administered to bring a patient into a remission or abatement of disease symptoms.

granulocytes

one type of white blood cell. It destroys invading bacteria which can cause disease.

HLA

human leukocyte antigens; structures which appear on white blood cells as well as cells of almost all other tissues. By typing for HLA antigens, donors and recipients of white blood cells, platelets, and bone marrow can be "matched" to insure survival of transfused and transplanted cells.

hyperalimentation

intravenous administration of nutrients. It is also called total parenteral nutrition (TPN).

immune response

the body's defense against disease and foreign substances, including transplanted bone marrow. During the immune system response, a substance can be ingested by a cell, recognized as "foreign," and then "killed" by other cells or a substance specifically formed against it.

infection

the invasion and multiplication of disease-producing organisms within the body.

intravenous

the administration of a drug or fluid substance directly into the vein.

leukemia

a malignant disease of the blood-forming tissues, including the bone marrow. Leukemia results in the uncontrolled production and growth of abnormal white blood cells.

leukocytes

white blood cells. They play a major part in the body's defense against infection and disease. These cells are divided into three main subgroups: granulocytes, lymphocytes and monocytes.

lymphatic system

tissues found throughout the body which contain the infection-fighting white blood cells.

lymphoma

the name of a group of malignant disorders affecting lymphatic tissues.

malignant

cancerous; characterized by an abnormal growth of cells.

platelet

one of the main components of blood that produces clots to seal up injuries and prevent excessive bleeding.

radiation therapy

treatment using high energy radiation, as from x-ray machines.

red blood cells

cells that carry oxygen to all parts of the body; also called erythrocytes.

relapse

the reappearance of a disease after a period in which symptoms of the disease had lessened or disappeared.

remission

the disappearance of symptoms of a disease. Also, the period during which no evidence of disease is present.

toxicity

the state of being poisonous or causing in effects.

Public Education Medical Advisory Committee

Chairman

Kathleen A. Hays, R.N., M.N.

Clinical Nurse Manager

University of Pittsburgh Medical Center

Lawrence D. Ellis, M.D.

Clinical Professor of Medicine

University of Pittsburgh

Samuel Gross, M.D.

Medical Director

Walt Disney Memorial Cancer Institute

at Florida Hospital, Orlando

Lynna Lesko, M.D., Ph.D.

Assistant Director, International Clinical Research-CNS

Hoffman LaRoche, Inc.

Nutley, New Jersey

Adjunct Associate Attending Psychiatrist

Memorial Sloan-Kettering Cancer Center

New York, New York

Dennis F. Moore, M.D.

Clinical Professor of Medicine

Kansas University School of Medicine, Wichita

Seth A. Rudnick, M.D.

President and CEO

Cytotherapeutics, Inc., Providence

Vice Chairman, Medical and Scientific Affairs

Ronald P. McCaffrey, M.D.

Chief, Section of Medical Oncology

Boston University Medical Center
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Title Annotation:includes bibliography and glossary
Publication:Pamphlet by: Leukemia Society of America
Article Type:Pamphlet
Date:Jun 1, 1993
Words:5406
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