People affected by T-cell prolymphocytic leukemia typically have systemic disease at presentation, including enlargement of the liver and spleen, widespread enlargement of the lymph nodes, and skin infiltrates.

Due to the systemic nature of this disease, leukemic cells can be found in peripheral blood, lymph nodes, bone marrow, spleen, liver, and skin. A high lymphocyte count (> 100 x 10/L) along with low amounts of red blood cells and platelets in the blood are common findings. HTLV-1 serologies are negative, and serum immunoglobins are within normal limits with no paraproteins present.

Patients usually present with constitutional symptoms (malaise, weight loss, fatigue), and hepatosplenomegaly is commonly found on physical exam. Lymphadenopathy is also found to a lesser extent. Due to the aggressive nature of the disease, patients may initially present at a more advanced stage, with coagulopathies, hemophagocytic syndrome, and multi-organ failure.

Initial symptoms can be nonspecific, particularly in children. Over 50% of children with leukemia had one or more of five features: a liver one can feel (64%), a spleen one can feel (61%), pale complexion (54%), fever (53%), and bruising (52%). Additionally, recurrent infections, feeling tired, arm or leg pain, and enlarged lymph nodes can be prominent features. The B symptoms, such as fever, night sweats, and weight loss, are often present as well.

Central nervous system (CNS) symptoms such cranial neuropathies due to meningeal infiltration are identified in less than 10% of adults and less than 5% of children, particularly mature B-cell ALL (Burkitt leukemia) at presentation.

The signs and symptoms of ALL are variable and include:

- Generalized weakness and feeling tired

- Anemia

- Dizziness

- Headache, vomiting, lethargy, nuchal rigidity, or cranial nerve palsies (CNS involvement)

- Frequent or unexplained fever and infection

- Weight loss and/or loss of appetite

- Excessive and unexplained bruising

- Bone pain, joint pain (caused by the spread of "blast" cells to the surface of the bone or into the joint from the marrow cavity)

- Breathlessness

- Enlarged lymph nodes, liver and/or spleen

- Pitting edema (swelling) in the lower limbs and/or abdomen

- Petechiae, which are tiny red spots or lines in the skin due to low platelet levels

- Testicular enlargement

- Mediastinal mass

This disease is known for an indolent clinical course and incidental discovery. The most common physical finding is moderate splenomegaly. B symptoms are seen in a third of cases, and recurrent infections due to the associated neutropenia are seen in almost half of cases.

Rheumatoid arthritis is commonly observed in people with T-LGLL, leading to a clinical presentation similar to Felty's syndrome. Signs and symptoms of anemia are commonly found, due to the association between T-LGLL and erythroid hypoplasia.

"T-cell leukemia" describes several different types of lymphoid leukemias which affect T cells.

The most common T-cell leukemia is precursor T-cell lymphoblastic leukemia. It causes 15% of acute leukemias in childhood, and also 40% of lymphomas in childhood. It is most common in adolescent males. Its morphology is identical to that of "precursor B-cell lymphoblastic leukemia". Cell markers include TdT, CD2, CD7. It often presents as a mediastinal mass because of involvement of the thymus. It is highly associated with NOTCH1 mutations.

Other types include:

- Large granular lymphocytic leukemia

- Adult T-cell leukemia/lymphoma

- T-cell prolymphocytic leukemia

In practice, it can be hard to distinguish T-cell leukemia from T-cell lymphoma, and they are often grouped together.

Historically, they have been most commonly divided by the stage of maturation at which the clonal (neoplastic) lymphoid population stopped maturing:

- Acute lymphoblastic leukemia

- Chronic lymphocytic leukemia

However, the influential WHO Classification (published in 2001) emphasized a greater emphasis on cell lineage. To this end, lymphoid leukemias can also be divided by the type of cells affected:

- B-cell leukemia

- T-cell leukemia

- NK-cell leukemia

The most common type of lymphoid leukemia is B-cell chronic lymphocytic leukemia.

In hairy cell leukemia, the "hairy cells" (malignant B lymphocytes) accumulate in the bone marrow, interfering with the production of normal white blood cells, red blood cells, and platelets. Consequently, patients may develop infections related to low white blood cell count, anemia and fatigue due to a lack of red blood cells, or easy bleeding due to a low platelet count. Leukemic cells may gather in the spleen and cause it to swell; this can have the side effect of making the person feel full even when he or she has not eaten much.

Hairy cell leukemia is commonly diagnosed after a routine blood count shows unexpectedly low numbers of one or more kinds of normal blood cells, or after unexplained bruises or recurrent infections in an otherwise apparently healthy patient.

Platelet function may be somewhat impaired in HCL patients, although this does not appear to have any significant practical effect. It may result in somewhat more mild bruises than would otherwise be expected for a given platelet count or a mildly increased bleeding time for a minor cut. It is likely the result of producing slightly abnormal platelets in the overstressed bone marrow tissue.

Patients with a high tumor burden may also have somewhat reduced levels of cholesterol, especially in patients with an enlarged spleen. Cholesterol levels return to more normal values with successful treatment of HCL.

It is postulated that the originating cell line for this disease is a mature (post-thymic) T-cell.

The way CML presents depends on the stage of the disease at diagnosis as it has been known to skip stages in some cases.

Most patients (~90%) are diagnosed during the chronic stage which is most often asymptomatic. In these cases it may be diagnosed incidentally with an elevated white blood cell count on a routine laboratory test. It can also present with symptoms indicative of hepatosplenomegaly and the resulting upper quadrant pain this causes. The enlarged spleen may put pressure on the stomach causing a loss of appetite and resulting weight loss. It may also present with mild fever and night sweats due to an elevated basal level of metabolism.

Some (<10%) are diagnosed during the accelerated stage which most often presents bleeding, petechiae and ecchymosis. In these patients fevers are most commonly the result of opportunistic infections.

Some patients are initially diagnosed in the blast phase in which the symptoms are most likely fever, bone pain and an increase in bone marrow fibrosis.

The leukemic cells of T-LGLL can be found in peripheral blood, bone marrow, spleen, and liver. Nodal involvement is rare.

This disease is typically found and diagnosed in peripheral blood, and while it can involve any organ, it is usually found in the spleen, liver, and bone marrow.

A B-cell leukemia is any of several types of lymphoid leukemia which affect B cells.

Types include (with ICD-O code):

- 9823/3 - B-cell chronic lymphocytic leukemia/small lymphocytic lymphoma

- 9826/3 - Acute lymphoblastic leukemia, mature B-cell type

- 9833/3 - B-cell prolymphocytic leukemia

- 9835/3-9836/3 - Precursor B lymphoblastic leukemia

- 9940/3 - Hairy cell leukemia

Acute mast cell leukemia is a rapidly progressive disorder with leukemic mast cells in blood and in large numbers in marrow. The common signs and symptoms include fever, headache, flushing of face and trunk. The typical cutaneous mast cell infiltrates of urticaria pigmentosa are usually not present before, during, or after diagnosis in patients who have mast cell leukemia. Symptoms include abdominal pain, bone pain, and peptic ulcer which are more prevalent than in other subtypes of acute myeloid leukemia. These former symptoms are due to release of a substance called histamine from neoplastic mast cells. Enlargement of the liver and spleen, or hepatosplenomegaly is characteristic. The mast cells release also many anticoagulants like heparin which can lead to serious bleeding. Liver and splenic dysfunction also contributes to hemorrhage. Involvement of the bone can lead to osteoporosis. Abdominal ultrasound or computerized tomography (CT) scanning is used to look for hepatosplenomegaly and lymphadenopathy. Plain radiography and bone densitometry can be used to assess bone involvement and the presence of osteoporosis. Endoscopy and biopsy can be useful if gut involvement is suspected.

T-cell leukemia describes several different types of lymphoid leukemia which affect T cells.

Types include:

- Large granular lymphocytic leukemia

- Adult T-cell leukemia/lymphoma

- T-cell prolymphocytic leukemia

In practice, it can be hard to distinguish T-cell leukemia from T-cell lymphoma, and they are often grouped together.

BAL has similar symptoms with other types of leukemia, but usually more serious.

Symptoms caused by bone marrow damage

Bruising, spotting: the reason is lack of platelets, it is very common in BAL patients, most of patients die due to the

Anemia: Because the decline of hematopoietic function, need blood transfusion therapy

Persistent fever, infection prolonged healing:

Diffuse hemorrhage: also called Septicemia, which is dangerous and might lead to death.

Symptoms caused by blood cancer cells infiltration into tissues:

Lymphadenopathy

Joint pain

Swelling of the gums

Hepatoslenomegaly

Headache and vomiting: blood cancer infiltration into the wear performance of the central nervous system.

Skin lumps: Because look was slightly green, also known as the "Green tumor."

Pericardial or pleural effusion

Most people are diagnosed without symptoms as the result of a routine blood test that shows a high white blood cell count. Less commonly, CLL may present with enlarged lymph nodes without a high white blood cell count or no evidence of the disease in the blood. This is referred to as small lymphocytic lymphoma. In some individuals, the disease comes to light only after the cancerous cells overwhelm the bone marrow resulting in anemia producing tiredness or weakness.

The most common symptoms in children are easy bruising, pale skin, fever, and an enlarged spleen or liver.

Damage to the bone marrow, by way of displacing the normal bone marrow cells with higher numbers of immature white blood cells, results in a lack of blood platelets, which are important in the blood clotting process. This means people with leukemia may easily become bruised, bleed excessively, or develop pinprick bleeds (petechiae).

White blood cells, which are involved in fighting pathogens, may be suppressed or dysfunctional. This could cause the patient's immune system to be unable to fight off a simple infection or to start attacking other body cells. Because leukemia prevents the immune system from working normally, some patients experience frequent infection, ranging from infected tonsils, sores in the mouth, or diarrhea to life-threatening pneumonia or opportunistic infections.

Finally, the red blood cell deficiency leads to anemia, which may cause dyspnea and .

Some patients experience other symptoms, such as feeling sick, having fevers, chills, night sweats, feeling fatigued and other flu-like symptoms. Some patients experience nausea or a feeling of fullness due to an enlarged liver and spleen; this can result in unintentional weight loss. Blasts affected by the disease may come together and become swollen in the liver or in the lymph nodes causing pain and leading to nausea.

If the leukemic cells invade the central nervous system, then neurological symptoms (notably headaches) can occur. Uncommon neurological symptoms like migraines, seizures, or coma can occur as a result of brain stem pressure. All symptoms associated with leukemia can be attributed to other diseases. Consequently, leukemia is always diagnosed through medical tests.

The word "leukemia", which means 'white blood', is derived from the characteristic high white blood cell count that presents in most afflicted patients before treatment. The high number of white blood cells are apparent when a blood sample is viewed under a microscope, with the extra white blood cells frequently being immature or dysfunctional. The excessive number of cells can also interfere with the level of other cells, causing further harmful imbalance in the blood count.

Some leukemia patients do not have high white blood cell counts visible during a regular blood count. This less-common condition is called "aleukemia". The bone marrow still contains cancerous white blood cells which disrupt the normal production of blood cells, but they remain in the marrow instead of entering the bloodstream, where they would be visible in a blood test. For an aleukemic patient, the white blood cell counts in the bloodstream can be normal or low. Aleukemia can occur in any of the four major types of leukemia, and is particularly common in hairy cell leukemia.

ATL is usually a highly aggressive non-Hodgkin's lymphoma with no characteristic histologic appearance except for a diffuse pattern and a mature T-cell phenotype. Circulating lymphocytes with an irregular nuclear contour (leukemic cells) are frequently seen. Several lines of evidence suggest that HTLV-1 causes ATL. This evidence includes the frequent isolation of HTLV-1 from patients with this disease and the detection of HTLV-1 proviral genome in ATL leukemic cells. ATL is frequently accompanied by visceral involvement, hypercalcemia, skin lesions, and lytic bone lesions. Bone invasion and osteolysis, features of bone metastases, commonly occur in the setting of advanced solid tumors, such as breast, prostate, and lung cancers, but are less common in hematologic malignancies. However, patients with HTLV-1–induced ATL and multiple myeloma are predisposed to the development of tumor-induced osteolysis and hypercalcemia. One of the striking features of ATL and multiple myeloma induced bone disease is that the bone lesions are predominantly osteolytic with little associated osteoblastic activity. In patients with ATL, elevated serum levels of IL-1, TGFβ, PTHrP, macrophage inflammatory protein (MIP-1α), and receptor activator of nuclear factor-κB ligand (RANKL) have been associated with hypercalcemia. Immunodeficient mice that received implants with leukemic cells from patients with ATL or with HTLV-1–infected lymphocytes developed hypercalcemia and elevated serum levels of PTHrP. Most patients die within one year of diagnosis.

Infection with HTLV-1, like infection with other retroviruses, probably occurs for life and can be inferred when antibody against HTLV-1 is detected in the serum.

Chronic myelogenous leukemia (CML) is a cancer of the white blood cells. It is a form of leukemia characterized by the increased and unregulated growth of predominantly myeloid cells in the bone marrow and the accumulation of these cells in the blood. CML is a clonal bone marrow stem cell disorder in which a proliferation of mature granulocytes (neutrophils, eosinophils and basophils) and their precursors is found. It is a type of myeloproliferative neoplasm associated with a characteristic chromosomal translocation called the Philadelphia chromosome.

CML is largely treated with targeted drugs called tyrosine-kinase inhibitors (TKIs) which have led to dramatic improved long-term survival rates since 2001. These drugs have revolutionized treatment of this disease and allow most patients to have a good quality of life when compared to the former chemotherapy drugs. In Western countries, CML accounts for 15–25% of all adult leukemias and 14% of leukemias overall (including the pediatric population, where CML is less common).

Hairy cell leukemia is an uncommon hematological malignancy characterized by an accumulation of abnormal B lymphocytes. It is usually classified as a sub-type of chronic lymphoid leukemia. Hairy cell leukemia makes up approximately 2% of all leukemias, with fewer than 2,000 new cases diagnosed annually in North America and Western Europe combined.

Hairy cell leukemia was originally described as histiocytic leukemia, malignant reticulosis, or lymphoid myelofibrosis in publications dating back to the 1920s. The disease was formally named leukemic reticuloendotheliosis and its characterization significantly advanced by Bertha Bouroncle and colleagues at The Ohio State University College of Medicine in 1958. Its common name, which was coined in 1966, is derived from the "hairy" appearance of the malignant B cells under a microscope.

Chronic lymphoid leukemia (CLL) is a type of cancer in which the bone marrow makes too many lymphocytes (a type of white blood cell). Early on there is typically no symptoms. Latter non-painful lymph nodes swelling, feeling tired, fever, or weight loss for no clear reason may occur. Enlargement of the spleen and anemia may also occur. It typically worsens gradually.

Risk factors include having a family history of the disease. Agent Orange and certain insecticides might also be a risk. CLL results in the build up of B cell lymphocytes in the bone marrow, lymph nodes, and blood. These cells do not function well and crowd out healthy blood cells. It is divided into two main types those with a mutated IGHV gene and those without. Diagnosis is typically based on blood tests finding high numbers of mature lymphocytes and smudge cells.

Management of early disease is generally with watchful waiting. Infections should more readily be treated with antibiotics. In those with significant symptoms chemotherapy or immunotherapy may be used. The medications fludarabine, cyclophosphamide, and rituximab are typically the initial treatment in those who are otherwise healthy.

CLL affected about 904,000 people globally in 2015 and resulted in 60,700 deaths. The disease most common occurs in people over the age of 50. Males are affected more often than females. It is much less common in people from Asia. Five-year survival following diagnosis is approximately 83% in the United States. It represents less than 1% of deaths from cancer.

Symptoms of Richter’s transformation in a CLL patient include fever (without infection), an elevated serum levels of lactate dehydrogenase, and rapidly enlarging lymph nodes. While about 8% of all CLL patients will have elevated levels of serum lactate dehydrogenase (LDH), more than 50% of CLL patients with Richter's transformation will have elevated LDH levels.

Richter's can appear suddenly, even in patients who were in remission.

Mast cell leukemia is an extremely aggressive subtype of acute myeloid leukemia that usually occurs "de novo" but can, rarely, evolve from transformation of chronic myeloid leukemia into the more aggressive acute myeloid leukemia. In a small proportion of cases, acute mast cell leukemia may evolve from a more progressive form of systemic mastocytosis. The diagnosis of acute mast cell leukemia by the WHO criteria includes the requirement for a prevalence of 20% neoplastic mast cells in marrow and 10% in blood. If the mast cells represent less than 10% of blood cells, the tumor is called "aleukemic" mast cell leukemia.

Most signs and symptoms of AML are caused by the replacement of normal blood cells with leukemic cells. A lack of normal white blood cell production makes people more susceptible to infections; while the leukemic cells themselves are derived from white blood cell precursors, they have no infection-fighting capacity. A drop in red blood cell count (anemia) can cause fatigue, paleness, and shortness of breath. A lack of platelets can lead to easy bruising or bleeding with minor trauma.

The early signs of AML are often vague and nonspecific, and may be similar to those of influenza or other common illnesses. Some generalized symptoms include fever, fatigue, weight loss or loss of appetite, shortness of breath, anemia, easy bruising or bleeding, petechiae (flat, pin-head sized spots under the skin caused by bleeding), bone and joint pain, and persistent or frequent infections.

Enlargement of the spleen may occur in AML, but it is typically mild and asymptomatic. Lymph node swelling is rare in AML, in contrast to acute lymphoblastic leukemia. The skin is involved about 10% of the time in the form of leukemia cutis. Rarely, Sweet's syndrome, a paraneoplastic inflammation of the skin, can occur with AML.

Some people with AML may experience swelling of the gums because of infiltration of leukemic cells into the gum tissue. Rarely, the first sign of leukemia may be the development of a solid leukemic mass or tumor outside of the bone marrow, called a chloroma. Occasionally, a person may show no symptoms, and the leukemia may be discovered incidentally during a routine blood test.

Acute lymphoblastic leukemia (ALL) is a cancer of the lymphoid line of blood cells characterized by the development of large numbers of immature lymphocytes. Symptoms may include feeling tired, pale skin color, fever, easy bleeding or bruising, enlarged lymph nodes, or bone pain. As an acute leukemia, ALL progresses rapidly and is typically fatal within weeks or months if left untreated.

Most cases occur due to an unknown reason. Genetic risk factors may include Down syndrome, Li-Fraumeni syndrome, or neurofibromatosis type 1. Environment risk factors may include significant radiation exposure or prior chemotherapy. Evidence regarding electromagnetic fields or pesticides is unclear. Some hypothesize that an abnormal immune response to a common infection may be a trigger. The underlying mechanism involves multiple genetic mutations that results in rapid cell division. The excessive immature lymphocytes in the bone marrow interfere with the production of new red blood cells, white blood cells, and platelets. Diagnosis is typically based on blood tests and bone marrow examination.

ALL is typically treated initially with chemotherapy aimed at bringing about remission. This is then followed by further chemotherapy typically over a number of years. Additional treatments may include intrathecal chemotherapy or radiation therapy if spread to the brain has occurred. Stem cell transplantation may be used if the disease recurs following standard treatment. Additional treatments such as immunotherapy are being studied.

ALL affected about 876,000 people globally in 2015 and resulted in about 111,000 deaths. It occurs most commonly in children, particularly those between the ages of two and five. In the United States it is the most common cause of cancer and death from cancer among children. ALL is notable for being the first disseminated cancer to be cured. Survival for children increased from under 10% in the 1960s to 90% in 2015. Survival rates remain lower for babies (50%) and adults (35%).