ALL is the commonest of childhood cancers and accounts for almost 25% of all cancers in children below the age of 15 years.

Acute lymphoblastic leukemia has, over the last decade or two, evolved and served as an ideal model for diagnosing and treating cancers in children as well as in adults.

Research and advances has resulted in development of the best combination of chemotherapy that has improved the cure rate, especially in children, to almost 70 to 80%.

What is ALL?

Acute Lymphoblastic Leukemia is a form of blood cancer that is characterized by the abnormal proliferation of the lymphoblasts in the bone marrow and the lymph. ALL has the ability to evolve over a short period of time.

'Acute' refers to the fact that -

• The disease appears suddenly,
  
• Is fast- developing, and
  
• May quickly spread to other vital organs.

In a healthy individual, the T- cells and B- cells are the two different types of lymphocytes that produce antibodies to fight infections. These lymphocytes are distributed in the blood, lymph nodes, and spleen.

In patients with ALL, the lymphocytes remain immature and are referred to as lymphoblasts. These immature cells rapidly proliferate and outnumber other blood cells in the blood, bone marrow, and lymph tissue.


Microscopic view of Acute Lymphoblastic Leukemia
In the majority of ALL cases (85%), the B-cell lymphocytes are affected, while in the rest, the T-cells are altered.

ALL is fatal if left untreated and therefore requires immediate attention. Certain varieties of acute leukemia respond favorably to treatment and several affected individuals are successfully cured. However, there are certain types that do not have a pleasing prognosis.