LEUKEMIA - A General Overview

Leukaemia is a cancer of blood-forming cells. There are different types. If you develop leukaemia it is important to know what type it is. This is because the outlook (prognosis) and treatments vary for the different types. 

This leaflet gives a general overview. Separate leaflets 
give more details about the different types of leukaemia (see under 'What is the treatment for leukaemia?' below).

What is leukaemia?

Leukaemia is a cancer of cells in the bone marrow (the cells which develop into blood cells).

Cancer is a disease of the cells in the body. There are many types of cancer which arise from different types of cell. What all cancers have in common is that the cancer cells are abnormal and do not respond to normal control mechanisms. Large numbers of cancer cells build up because they multiply 'out of control', or because they live much longer than normal cells, or both.

With leukaemia, the cancerous cells in the bone marrow spill out into the bloodstream. There are several types of leukaemia. Most types arise from cells which normally develop into white blood cells. (The word leukaemia comes from a Greek word which means 'white blood'.) If you develop leukaemia it is important to know exactly what type it is. This is because the outlook (prognosis) and treatments vary for the different types. Before discussing the different types of leukaemia it may help to know some basics about normal blood cells and how they are made.

What is normal blood made up of?

• Blood cells, which can be seen under a microscope, make up about 40% of the blood's volume. Blood cells are divided into three main types:
  • Red cells (erythrocytes). These make blood a red colour. One drop of blood contains about five million red cells. Red cells contain a chemical called haemoglobin. This binds to oxygen, and takes oxygen from the lungs to all parts of the body.
  • White cells (leukocytes). There are different types of white cells, which are called neutrophils (polymorphs), lymphocytes, eosinophils, monocytes, and basophils. They are part of the immune system. Their main role is to defend the body against infection.
  • Platelets. These are tiny and help the blood to clot if we cut ourselves.
• Plasma is the liquid part of blood and makes up about 60% of the blood's volume. Plasma is mainly made from water, but contains many different proteins and other chemicals, such as hormones, antibodies, enzymes, glucose, fat particles, salts, etc.

When blood spills from your body (or a blood sample is taken into a plain glass tube) the cells and certain plasma proteins clump together to form a clot. The remaining clear fluid is called serum.

The bone marrow, stem cells and blood cell production

Bone marrow

Blood cells are made in the bone marrow by 'stem' cells. The bone marrow is the soft 'spongy' material in the centre of bones. The large flat bones, such as the pelvis and breast-bone (sternum), contain the most bone marrow. To make blood cells constantly you need a healthy bone marrow. You also need nutrients from your diet, including iron and certain vitamins.

Stem cells

Stem cells are primitive (immature) cells. There are two main types in the bone marrow - myeloid and lymphoid stem cells. These derive from even more primitive common 'pleuripotent' stem cells. Stem cells constantly divide and produce new cells. Some new cells remain as stem cells and others go through a series of maturing stages ('precursor' or 'blast' cells) before forming into mature blood cells. Mature blood cells are released from the bone marrow into the bloodstream.

• Lymphocyte white blood cells develop from lymphoid stem cells. There are three types of mature lymphocytes:
  • B lymphocytes make antibodies which attack infecting bacteria, viruses, etc.
  • T lymphocytes help the B lymphocytes to make antibodies.
  • Natural killer cells, which also help to protect against infection.

All the other different blood cells (red blood cells, platelets, neutrophils, basophils, eosinophils and monocytes) develop from myeloid stem cells.

Blood production

You make millions of blood cells every day. Each type of cell has an expected life-span. For example, red blood cells normally last about 120 days. Some white blood cells last just hours or days - some last longer. Every day millions of blood cells die and are broken down at the end of their life-span. There is normally a fine balance between the number of blood cells that you make, and the number that die and are broken down. Various factors help to maintain this balance. For example, certain hormones in the bloodstream and chemicals in the bone marrow called 'growth factors' help to regulate the number of blood cells that are made.

The main types of leukaemia are:

• Acute lymphoblastic leukaemia - 'ALL' (sometimes called acute lymphocytic leukaemia).
• Acute myeloid leukaemia - 'AML'.
• Chronic lymphocytic leukaemia - 'CLL'.
• Chronic myeloid leukaemia - 'CML'.

There are various 'sub-types' of each of these. In addition there are some other rare types of leukaemia. The word:

• 'Acute' means the disease develops and progresses quite quickly.
• 'Chronic' means persistent or ongoing. When talking about leukaemia, the word chronic also means that the disease develops and progresses slowly (even without treatment).
• 'Lymphoblastic' and 'lymphocytic' mean that an abnormal cancerous cell is a cell that originated from a lymphoid stem cell.
• 'Myeloid' means that an abnormal cancerous cell is a cell that originated from a myeloid stem cell.

There are separate leaflets (listed below) that give details about each of these types of leukaemia. Briefly:

Acute lymphoblastic leukaemia

In acute lymphoblastic leukaemia (ALL) the bone marrow makes large numbers of abnormal immature lymphocytes called lymphoblasts. There are various sub-types of ALL. For example, the abnormal lymphoblasts can be immature B or T lymphocytes. Typically, ALL develops quite quickly (acutely) and rapidly becomes worse (over a few weeks or so) unless treated. ALL can occur at any age, but about 6 in 10 cases occur in children. It is the most common form of leukaemia to affect children (although it is an uncommon disease).

Acute myeloid leukaemia

In acute myeloid leukaemia (AML) the bone marrow makes large numbers of abnormal immature white blood cells which are derived from a myeloid stem cell. The abnormal immature cells are called blasts. There are various sub-types of AML, depending on exactly what cell type becomes cancerous and at what stage in the maturing process. Typically, AML develops quite quickly (acutely) and rapidly becomes worse (over a few weeks or so) unless treated. AML is an uncommon disease. Most cases occur in people aged over 50.

Chronic lymphocytic leukaemia

In chronic lymphocytic leukaemia (CLL) you have many abnormal B lymphocytes. The main reason for the build-up of the abnormal lymphocytes is because they live too long - they do not die after the usual lifespan of a lymphocyte. (This is different to the acute types of leukaemia where the cells rapidly multiply 'out of control'. In CLL the abnormal lymphocytes are not thought to multiply faster than normal lymphocytes.) Typically, CLL develops and progresses very slowly - over months or years, even without treatment. CLL is the most common type of leukaemia. It occurs in around 2,750 people each year in the UK. Most cases occur in people over at the age of 60.

Chronic myeloid leukaemia

Chronic myeloid leukaemia (CML) develops due to a problem with a stem cell in the bone marrow which becomes abnormal. The abnormal stem cell multiplies and the cells that are made from the abnormal stem cells mature and develop into near normal white cells - mainly neutrophils, basophils and eosinophils (collectively called granulocytes). Typically, CML develops and progresses slowly - over months or years, even without treatment. CML is the rarest of the four main types of leukaemia. There are fewer than 1,000 cases in the UK each year. It occurs mainly in adults, and becomes more common with increasing age.

What causes leukaemia?

A leukaemia is thought to start first from one abnormal cell. What seems to happen is that certain vital genes which control how cells divide, multiply and die, are damaged or altered. This makes the cell abnormal. If the abnormal cell survives it may multiply 'out of control' or survive a long time, and develop into a leukaemia.

In most cases of leukaemia, the reason why a cell becomes abnormal is not known. There are certain 'risk factors' which increase the chance that certain leukaemias will develop, but these only account for a small number of cases. Risk factors for some types of leukaemia include:

• Radiation. For example, previous radiotherapy for another condition. Many of the survivors of the atom bomb used in World War II developed leukaemia due to the fall out of radiation.
• Past treatment with chemotherapy or other drugs that weaken the immune system.
• Certain genetic disorders, the most common being Down's syndrome.
• Exposure to certain chemicals such as benzene.

What are the main symptoms of leukaemia?

As large numbers of abnormal blood cells are made, much of the bone marrow fills with these abnormal cells. Because of this it is difficult for normal cells in the bone marrow to survive and make enough normal mature blood cells. Also, the abnormal cells spill out into the bloodstream. Therefore, the main problems which can develop include:

• Anaemia. This occurs as the number of red blood cells in the bloodstream goes down. This can cause tiredness, breathlessness and other symptoms. You may also look pale.
• Blood clotting problems. This is due to low levels of platelets in the bloodstream. This can cause easy bruising, bleeding from the gums and other bleeding-related problems.
• Serious infections. The abnormal white blood cells do not protect against infection. Also, there is a reduced number of normal white blood cells which usually combat infection. Therefore, serious infections are more likely to develop. Depending on the type and site of infection which develops, the symptoms can vary greatly.

The time taken to develop these symptoms after the disease starts varies. Typically, it is within weeks for ALL or AML. It may take months or years for symptoms to develop with CLL or CML, as these leukaemias progress slowly.

The abnormal cells may also build up in lymph glands and in the spleen. You may therefore develop swollen glands in various parts of the body, and develop an enlarged spleen.

Other symptoms which may develop include: pain in the bones or joints (mainly with ALL), persistent fever and weight loss.

How is leukaemia diagnosed and assessed?

A blood test

A blood test can often suggest the diagnosis of leukaemia, as abnormal cells are often detected in the blood test. Further tests are usually done to confirm the diagnosis.

A bone marrow sample

For this test a small amount of bone marrow is removed by inserting a needle into the pelvis bone (or sometimes the breastbone (sternum)). Local anaesthetic is used to numb the area. A small sample of bone may also be taken. The samples are put under the microscope to look for abnormal cells and are also tested in other ways. This can confirm the diagnosis. (See separate leaflet called 'Biopsy - Bone Marrow' for more detail.) A bone marrow test may not be needed to confirm the diagnosis of CLL.

Cell and chromosome analysis

Detailed tests are often done on abnormal cells obtained from the bone marrow sample or blood test. These find out the exact type, or sub-type, of the cell that is abnormal.

Lumbar puncture

This test collects a small amount of fluid from around the spinal cord - cerebrospinal fluid (CSF). It is done by inserting a needle between the vertebrae in the lower (lumbar) region of the back. (See separate leaflet called 'Lumbar Puncture' for more detail on this test.) By examining the fluid for leukaemia cells, it helps to to find out if the leukaemia has spread to the brain and spinal cord. This is mainly done when assessing ALL and sometimes AML.

Various other tests

A chest X-ray, blood tests and other tests are usually done to assess your general wellbeing.

What is the treatment for leukaemia?

The treatment advised depends on the exact type of leukaemia, and the stage it is at. For example, ALL is usually treated as soon as possible with intensive chemotherapy. On the other hand, people in the early stages of CLL may not need any treatment. This is because CLL often progresses very slowly and may not need treatment for several years.

For details of treatments for each type of leukaemia, see separate leaflets called:

• Acute Lymphoblastic Leukaemia
• Acute Myeloid Leukaemia
• Chronic Lymphocytic Leukaemia
• Chronic Myeloid Leukaemia

What is the outlook (prognosis)?

The outlook varies for each of the different leukaemias. However, the overall outlook may be better than many people imagine. For example, the outlook for ALL has greatly improved over the last 20 years or so. Most children with ALL (about 7-8 in 10 cases) can be cured. Also, the chronic leukaemias (CLL and CML) often progress slowly - often over several years. Even in those cases which are not cured, treatment with chemotherapy and other treatments can often prolong survival for quite some time.

The treatment of cancer and leukaemia is a developing area of medicine. New treatments continue to be developed and the information on outlook above is very general. There are some newer drugs that have been introduced in the last few years that show promise to improve the outlook. The specialist who knows your case can give more accurate information about the treatment and outlook for your particular situation.

Source: http://www.patient.co.uk/

LEUKEMIA - Signs and symptoms of leukemia

A sign is something that can be observed and recognized by a doctor or healthcare professional (for example, a rash). A symptom is something that only the person experiencing it can feel and know (for example, pain or tiredness). The signs and symptoms of leukemia can also be caused by other health conditions. It is important to have any unusual symptoms checked by a doctor.

Signs and symptoms of acute leukemia (fast growing) may be similar to the flu and come on suddenly within days or weeks.

In the early stages of chronic leukemia (slow growing), many people have few or no symptoms. Signs and symptoms usually develop gradually and people will complain that they just do not feel well. The disease is often discovered during a routine blood test.

Signs and symptoms of leukemia are:

• fatigue
• malaise
• loss of appetite
• weight loss
• fever
• anemia
  • shortness of breath
  • paleness
  • palpitations (rapid heartbeat)
  • weakness
  • dizziness
• bleeding
  • widespread bruising
  • frequent or severe nose bleeds
  • bleeding gums
  • mid-cycle or heavy menstrual flow
  • red spots on the skin (petechiae)
• frequent infections
  • lungs (pneumonia)
  • urinary tract
  • gums
  • around the anus
  • cold sores
• vomiting
• headache
• sore throat
• night sweats
• bone or joint pain
• enlarged lymph nodes in the neck, underarm, groin or above the collarbone
• abdominal discomfort or feeling of fullness
• vision problems
• sores in the eyes
• swelling of the testicles

Rare signs and symptoms

Rare signs and symptoms of leukemia are:

• chloroma (granulocytic sarcoma) – a tumour-like collection of leukemia cells under the skin or in other parts of the body occur
• skin changes
  • Leukemia cutis occurs when leukemia cells enter the skin. The sores or patches can be any size and are usually pink or tan in colour.
  • Leukocytoclastic vasculitis resembles an allergic reaction on the skin. Sores usually appear on the extremities (hands and feet).
  • Sweet's syndrome (acute febrile neutrophilic dermatosis) includes fever and painful sores that may appear anywhere on the body.

Source: http://www.cancer.ca/en/cancer-information/cancer-type/leukemia/signs-and-symptoms/?region=on#ixzz3EPx6AIZA

CANCER - Mystery of the cancer cluster killing Chinese workers at factory that makes new iPhone 6: 13 struck by leukaemia in SAME plant... were cleaning agents to blame?

Mystery of the cancer cluster killing Chinese workers at factory that makes new iPhone 6: 13 struck by leukaemia in SAME plant... were cleaning agents to blame?

• Five staff at iPhone factory in Shenzhen, China have died from leukaemia 
• Cancer may have been caused by cleaning chemicals, victims' families say 
• One worker had only been at factory four months before he was diagnosed
• Feng Honggan, 20, suffered heavy nosebleeds in factory and has since died
• 
  

By SIMON PARRY IN SHENZEN, CHINA

PUBLISHED: 21:01 GMT, 13 September 2014 | UPDATED: 00:34 GMT, 14 September 2014

Apple is investigating its supply chain after the discovery of a disturbing cluster of leukaemia deaths among young workers at a factory in China where millions of its iPhones are made, The Mail on Sunday has learnt.

At least 13 workers in their late teens and early 20s have been diagnosed with leukaemia after falling sick at the massive factory in Shenzhen since 2010. Five have died – and at ages when doctors say cases of the blood cancer are rare. 

Families and a labour welfare group believe the leukaemia was caused by exposure to chemicals used to clean electrical panels and say many more workers could have been affected. They add that young workers who fall sick with leukaemia are dismissed and denied continuing medical coverage, bankrupting families as they desperately pay for treatment.

Scroll down for video 

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CONCERNS: Workers at the Foxconn factory in Shenzhen, where iPhones are made 

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Apple says it is taking the allegations ‘very seriously’ and is looking into the issue at the Shenzhen factory

Apple – whose launch celebrations for the iPhone 6 last week included a performance by Irish rock band U2 – says it is taking the allegations ‘very seriously’ and is looking into the issue at the Shenzhen factory, where about two million iPhones a week are made by an army of 230,000 migrant workers from across China. 

The factory is used for manufacturing by other electronics giants but has been the main production base for Apple’s iPhones since the first model in 2007.

Details of the leukaemia cluster emerged after Apple last month announced it was banning the use of two potentially toxic chemicals, benzene and n-hexane, in the final assembly of iPhones and iPads.

Foxconn, owner of the Shenzhen factory, is sending officials to meet the Hong Kong-based labour welfare group to find out more about the leukaemia cases, the labour group said.

However, the Taiwan-based company, which also makes products for other electronics giants, insisted there was no evidence to link the leukaemia cases to the victims’ work and said it had not used benzene and n-hexane ‘for many years’.

It also claimed the rate of leukaemia at its plants across China was ‘significantly lower than the reported annual rate’. Leukaemia affects about three people in 100,000 globally, but the majority of its victims are children and elderly people.

All 13 identified victims were aged between 19 and 24 when their cancer was diagnosed and were working on or near production lines mostly for iPhones and Apple products at the Longhua and Ganglan plants at Foxconn in Shenzhen, Labour Action China said.

Families of the victims said workers regularly used chemicals with only disposable plastic gloves and face masks for protection, were given little or no information about the potential dangers, and were not told which substances they were handling.

After falling sick at work and being diagnosed with leukaemia, the families of two workers said they were dismissed and paid off by Foxconn within three months, denying them medical cover to pay for hospital treatment.

The leukaemia cluster emerged when families visiting sick relatives in the cancer ward of the Number Two People’s Hospital in Shenzhen noticed how many other Foxconn workers were being treated.

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Charity, CureLeukaemia, explains what Leukaemia is

Cheng Fuying, whose son Yi Long is now in the advanced stages of leukaemia, said seven to eight workers a year from the same factory were diagnosed and admitted.

Yi Long, now 26, from a village in China’s Hubei province, was 22 when he began at Foxconn in March 2010, on a basic salary of £150 a month.

Speaking at her son’s hospital bedside, Ms Cheng said: ‘For the first month, he was cleaning all the machines with chemicals. He never knew what chemicals he was handling because they were given to him by the distributor up the line. He said he was just given a bucket of liquid to clean the machines. 

'After that, he changed jobs every month or two within the factory but he was on a production line when he fell ill. He started non-stop bleeding from his gums so co-workers helped him go to hospital.’

He was diagnosed with leukaemia.

‘I was shocked,’ said Ms Cheng, who has given up work to care for her son, sleeping on a mattress on the floor of his ward. ‘I had never even heard of that disease in my home town. I thought, “How could this happen?”’

A doctor treating Yi Long told Ms Cheng that chemicals at Foxconn might be to blame. ‘He told me Foxconn has a high incidence of this disease,’ she said, adding that the doctor had rounded angrily on Foxconn managers when they visited. 

‘The doctor told them, “You know why this is happening. Even your boss [Foxconn’s billionaire founder] Terry Gou’s brother died of leukaemia. You have so many patients in our hospital already. Do you really need to ask how he is?”’

Yi Long began a course of chemotherapy. Factory bosses told him he would have his wages paid to April and would then be dismissed.

Fellow workers collected about £6,000 towards Yi Long’s medical bills, while Foxconn paid him £3,000 for his termination, equivalent to a year’s wages with overtime.

By August 2012, Yi Long’s family could no longer afford his medical bills. ‘We asked for help from the factory but they said, “It’s not our fault, it’s your disease,” ’ Ms Cheng said. By then, she had discovered there were many other workers from Foxconn being treated for leukaemia at the same hospital.

‘There were seven or eight people from Foxconn who got leukaemia that year alone,’ she said.

A group of them protested outside the factory gates, demanding to see management, but were threatened with arrest unless they left. When their money ran out, Yi Long’s mother took him home to Hubei where they tried treating him with Chinese traditional medicine. He returned to Shenzhen in August last year as his condition worsened.

‘The doctors say he needs a bone-marrow transplant and they have found a donor but we have no money for the transplant,’ his mother said.

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The identity card belonged to Feng Honggan, who died of leukaemia last year aged just 20. He had been working at Foxconn’s Shenzhen plant for four months when he began to suffer heavy nose bleeds

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Celebrating: Apple CEO Tim Cook with U2 at the iPhone 6 launch last week 

Another worker, Feng Honggan, had been working at the factory for only four months when he was taken to hospital after suffering heavy nose bleeds in June 2011. He was diagnosed with leukaemia and died in November 2013, aged 20.

His parents Feng Huifeng and Qin Quixia, both 50, rented out their farm in Gansu, north-west China, and now work as street-cleaners in Shenzhen to try to pay off £80,000 of debt from paying for his treatment.

Honggan worked in the inventory of the factory, handing out materials and chemicals to workers. He wore disposable gloves and a face mask but was told by his bosses the chemicals were safe, his father said.

‘I talked to other patients and families in hospital and I found many of the patients had worked in Foxconn – a dozen or more,’ Mr Feng said.

A delegation of factory managers came to see Honggan in hospital. ‘First they came to see how he was doing. Then they brought him 21,000 renminbi [£2,100] and said, “This is a donation from the factory towards your illness.” They never came again and that was all he got.

‘Three months after he fell ill, they stopped paying him his wages, including his social insurance.’

Mr Feng went to the local government in Shenzhen to seek a ruling that his son’s death was the result of industrial disease, but he received a written reply saying Foxconn was a clean working environment that satisfied government requirements on chemical safety. 

Suki Chung, executive director of Labour Action China, said she believed the 13 known cases in Shenzhen were ‘the tip of the iceberg’ and that many more Foxconn workers had succumbed to the disease.

In most cases, workers had returned to their home provinces where they were entitled to free medical help after being dismissed, despite the fact that many rural hospitals lack facilities to treat them.

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The factory, in Shenzhen, China, is used for manufacturing by other electronics giants but has been the main production base for Apple’s iPhones since the first model in 2007

In an email to Labour Action China about the leukaemia cases, Apple’s senior director for supplier responsibility, Jacky Haynes, said Apple took the concerns ‘very seriously’, adding: ‘We are working closely with Foxconn on this matter.’

Before announcing its ban on benzene and n-hexane last month, Apple said it had conducted a four-month investigation into 22 factories and said it found no evidence that the chemicals endangered the 500,000 people working there.

An Apple spokesman said in a statement it had discovered ‘a few cases’ in which suppliers were using benzene or n-hexane before it banned the two chemicals from its final assembly lines. However, the statement said use of the two chemicals ‘was in low concentrations and each use complied with our Regulated Substances Specification’.

A spokesman for Foxconn said he could not comment on individual former employees but added in a statement: ‘The incidence of leukaemia among the over one million employees in our campuses across China is significantly lower than the reported national annual rate of incidence of leukaemia.

‘We can also confirm that the employees who were diagnosed with leukaemia held different positions and job functions while working at our company across different product lines and customers, as the majority of our campuses in China serve multiple customers and manufacture a variety of products – there is no commonality, including links with any chemical agents, associated with the work they were doing.

‘Foxconn does not allow any entity within our company to use benzene or n-hexane, and has not procured or used these chemicals in any aspect of our operations for many years.’

Ms Cheng told The Mail on Sunday she had a message for Apple CEO Tim Cook.

‘If you have a conscience, Apple should at least make sure my son’s disease is treated. I don’t want compensation. I just want his medical bills to be covered so that his disease can be treated to give him a chance to live,’ she said.

‘I know that without a bone- marrow transplant my son will probably die. But we don’t have the money to pay for it.’ 

Source: http://www.dailymail.co.uk