- Leukemia is a malignancy or cancer of the blood and bone marrow which primarily affects the white blood cells.
- The rapid growth and division of abnormal blood cells can overwhelm the presence of healthy blood cells, leading to an impairment of several cell activities.
- The fatality of leukemia or its actual prognosis would depend on a few factors such as the type of leukemia the person has, the age of the patient and his or her health status.
Leukemia is a malignancy or cancer of the blood and bone marrow which primarily affects the white blood cells- the blood cells responsible for fighting off infections and other foreign organisms that enter the bloodstream. With leukemia, the bone marrow produces a higher level of immature white blood cells, weakening the immune system. The disease also affects the red blood cells and platelets and its specific cell functions, as the rapid growth and division of the abnormal blood cells can overwhelm the presence of healthy blood cells leading to an impairment of several cell activities.
Depending on the person and type of cells the leukemia is attacking, different signs and symptoms will show. In the United States alone, there are about 54,000 new cases of leukemia that are diagnosed every year, and approximately less than 50 percent of those cases or about 24,000 people die from leukemia each year. It is believed that leukemia makes up three percent of the type of cancer in newly diagnosed patients. Thus, leukemia is a fatal disease, but there are treatment plans available and certain types of leukemia are less fatal than others.
Factors that affect fatality
The fatality of leukemia or its actual prognosis would depend on a few factors such as the type of leukemia the person has, the age of the patient and his or her health status. The progression of the disease will also affect prognosis. For example if the cancer has already spread out and is affecting vital body organs, it will be more fatal. Based on previous actual cases, elderly people with leukemia have a higher mortality rate compared to children and young adults.
Some types of leukemia, especially for children or the younger population, have a high survival rate of at least five years. With continuous advancements in medicine and cancer treatments, the chances of being treated and cured from leukemia grow each day.
As leukemia has the tendency to cause abnormal growth of white blood cells in any part of the body including the brain, spleen, liver, digestive system, lymph nodes, testicles, lungs, kidneys or eyes, the body shows an array of signs and symptoms. Leukemia is divided into stages depending on the disease type. The factors which decide and affect the fatality of the condition are:
- Medical history of blood disorders
- Bone damage
- Chromosome abnormalities or mutations
- White blood cell or platelet count
- Enlarged spleen or liver
One – five and ten-year survival for leukemia
For at least one- year 71 % men survive leukemia. For five year or more this falls to 54%. This statistic was based on diagnosis of leukemia patients during 2010-2011 in England and Wales. Whereas for women, for one - year 60% women survive leukemia and this falls to 49% for five years or more. Beyond five years after diagnosis the survival gradually decreases. It is predicted that 48% men and 44% women survive leukemia for ten years or more. This was based on patients diagnosed with leukemia 2010-2011 in e England and Wales.
Survival by age
In younger men and women five-year survival for leukemia is generally higher. This decreases as the age increases. For patients diagnosed with leukemia in England during the year 2009-2013 the net five - year survival in men ranges from 74% in 40-49-year-old to 29% in 80-99 year olds. The five-year survival in women ranges from 70% in 50-year-old to 23% in 80-99 year olds.
Survival rate over time
The survival rate is improving. Some of these are due to the changes in diagnosis, classification and registration. Interpretation of these should be undertaken carefully. In men one-year survival has increased from 35% in 1971-1972 to 71% in the year 2010-2011 in England and Wales. Whereas for women one-year survival has increased from 33% to 66%.
Since 1960 the overall survival rate has quadrupled. Major strides have been made in identifying treatment for leukemia which would be effective. Significant progress in understanding the underlying cause of the condition is being made by the scientist. Many people diagnosed with leukemia are living longer and high quality lives. New and better ways have been discovered and implemented to prevent diagnosis and treat the conditions.
Many factors that affect the rate for fatality are:
- Age of the patient at the time of diagnosis
- Whether the cancer cells have spread in the brain or spinal cord
- Whether the condition has recurred
- Patient’s response
Hence the survival rate can improve even further.
Types of leukemia
Based on the symptoms and facts, there are two major types of acute and chronic leukemia. These two major types are further divided into more than 12 types, but there are just four among the lot which are common in children and people between the age group of 41 to 60. The acute type is fatal, but chronic doesn’t cause immediate harm as it grows gradually. If left untreated for long, leukemia of any type can alter the production of important cells in the lymphatic system. Without treatment, one of the most common types, acute myeloid leukemia or ALL, can turn fatal more quickly than others, especially if left untreated. The reason behind the fatality is the fact that being acute in nature, this form of leukemia has the tendency to spread quickly to blood and major organs like liver and lymph nodes.
The four main types of leukemia are classified based on the progression of the diseases as well as the affected blood cells.
- The first type of leukemia is acute lymphocytic leukemia or ALL, and it happens when the bone marrow produces an abnormally high level of lymphocytes, which is a type of white blood cell. Acute lymphocytic leukemia most commonly occurs in teens and children, primarily between the ages of two and four, but adults may also develop this type of leukemia mostly at the age of 65 or higher. Cases have shown that children have a higher survival rate as compared to adults for at least five years, which is about 85 percent for young ones and 50 percent for the adult population with ALL.
- The second type of leukemia is chronic lymphocytic leukemia or CLL, which is a slow progressing condition with symptoms that may not appear for a couple of years. This type of leukemia affects the lymphoid cells which primarily are involved in the body’s immune system and most commonly occurs among middle aged adults, but can still be diagnosed among children and teenagers.
- The third type of leukemia is acute myeloid leukemia or AML, also known as acute myelogenous leukemia, is the most common acute type of leukemia among adults although it can still be diagnosed at any age. There is a rapid growth of myeloid cells with AML, which is involved in different cell functions including the immune system.
- The fourth type of leukemia is chronic myeloid leukemia, which ordinarily is only diagnosed in adults. A person with this type of leukemia may feel well for years and not show any symptoms of the disease that would result in seeking treatment.
Other less common types of leukemia include:
- Hairy cell leukemia
- Acute promyelocytic leukemia or APL, which is a subtype of AML
- Chronic myelomonocytic leukemia or CMML
- Juvenile myelomonocytic leukemia or JMML, which is diagnosed among children below six years old
- Large granular lymphocytic leukemia or LGL leukemia, which involves either an abnormally rapid or slow growth of lymphoid cells
Leukemia would manifest differently based on its type and progression. The signs and symptoms of leukemia are directly due to the effect of the overwhelming amount of abnormal blood cells compared to the amount of healthy cells which hamper the normal blood cell functions. With the chronic type of leukemia, the symptoms may appear after several years as there is a slow progression of the disease. With the acute type of leukemia, immediate medical attention is needed as the symptoms appear rapidly and are far worse.
The prognosis of leukemia is majorly based on a ‘five year survival rate’, meaning patients with this diagnosis should survive and live for five years or more after the diagnosis according to their doctor. Leukemia affects the red blood cells, lymphocytes and platelets. The red blood cells' function is to carry oxygen across the body. The lymphocytes make the immune system strong. The platelets are responsible for proper clotting of blood. Leukemic cancerous cells can travel through the bloodstream, engulf the bone marrow and attach vital organs of the body, making it an extremely dangerous disease.
Acute myeloid leukemia
Every year estimated 20,000 people in the United States with acute myeloid leukemia are diagnosed. On a yearly bases an estimated 10,000 deaths take place because of the disease. Many receive chemotherapy treatment. Chemotherapy is treating with medicines that rapidly kill the cancer cells. Roughly 70 to 80 percent of people younger than 60 after induction of chemotherapy will go into remission. In this condition symptoms of the disease are not experienced and blood cell counts are also in normal range. People older than 60 years don’t respond to the treatment and they also have a higher rate of fatality during the treatment. Some people may go into remission but they remain in that state. For patients with acute myeloid leukemia the five- year overall survival rate is 20 percent, which means an estimated of 26 out of thousand still live five years even after diagnosis. The five-year survival rate for lower risk acute myeloid leukemia groups is 65 percent.
Factors that affect fatality of patients with acute myeloid leukemia:
- Age: this can be a major factor in determining the response of the treatment. For people under the age of 60 diagnosed with acute myeloid leukemia, survival rate is more promising. The possible reason could be that since the body is not in good health it can make it difficult for their bodies to handle the strong medications of chemotherapy.
- Type of acute myeloid leukemia- several types exist depending on the type of leukemia cell present in the bone marrow and blood. Some have better survival outlook.
- Response to treatment- some people show better response to the treatment than others. Usually a person who has received chemotherapy treatment and the cancer hasn’t come back are considered curable. However, the treatment outcome is not favorable if it comes back or if the person doesn’t respond to the treatment at all.
- Prognosis is based on factors such as the outcome and analysis of blood test, imaging studies, bone marrow biopsies, and cerebrospinal fluid examination. Some people may show poor prognosis but may live for many years than predicted by the doctor.
Chronic lymphocytic leukemia
Its survival rate is higher than many other cancers. Five-year survival rate is 83 percent. In people with over the age of 75 this survival rate drops to less than 70 percent. The survival and fatality of chronic lymphocytic leukemia depends on myriad factors. This disease is more common in men especially those over the age of 60 and some people have a higher risk of developing it. Race, gender, family history, other blood disorder also increases the risk of developing chronic lymphocytic leukemia.
Factors that influence these include stage of the disease, response to the treatment along with certain cellular and genetic markers. Great promise has been show by the combination chemotherapy called FCR in patients who were previously treated, were in good heath and have certain favorable cellular markers. This treatment can increase the survival by increasing the number of years and possibly can induce a cure. However, this treatment is not suitable for people above 65 years old since their kidney function is poor.
Acute lymphoblastic leukemia
Estimated 6,590 people are diagnosed with this disease in United States in 2016. It leads to death of about 1,430 people. The survival rate depends on the age when diagnosed. The five-year survival rate is 85 percent. From 1975 to 1977 for all ages the five-year survival rate was 41 percent. For adults and children, the fiver year survival rate is 69 percent. However, the survival rate is improving and continues to improve over time.
Factors that affect fatality:
- Age: according to National Cancer Institute people diagnosed with acute lymohocytic leukemia and are 35 years old or less have a better chance of survival. Children over age 10 have higher risk. Older adults have poor prognosis.
- Subtype of acute lymphocytic leukemia: Generally, those with cell subtypes pre-B, common or early pre –B have better chances of survival than those with mature B-cell leukemia.
Chromosomal abnormalities: Different changes can occur on person chromosomes due to the cancers that cause acute lymphocytic leukemia. It causes chromosomal abnormalities and these are associated with poorer prognosis. These abnormalities include:
- Ph1-positibe t (9; 22) abnormities
- BCR/ABL-rearranged leukemia
- t (4;11)
- Deletion of chromosome 7
- Trisomy 8
- Response to the therapy: People who show quick response to the therapy have a better survival outlook. Outlook is not good if the treatment takes longer duration to reach remission. Prognosis can get affected if it takes longer than four weeks to reach remission.
- Spread to nearby organs: Survival outlook is poorer if acute lymphocytic leukemia spreads to the nearby organs including the CSF.
- At the time of prognosis white blood cell count- usually the prognosis is poorer if the white blood cell count is higher during the diagnosis.
There are several different treatments for leukemia. Typically, it is treated through medications and chemotherapy. It is the infection that makes the immune system weak and kills the person.