MCQ Detailed View

Most cancers are known to form solid tumors—abnormal masses of tissue caused by uncontrolled cell division. Examples include breast cancer, lung cancer, and bladder cancer. However, not all cancers behave this way. The type of cancer that does not form a tumor is leukemia.

Leukemia is a cancer of the blood and bone marrow. Instead of producing a solid lump, it results in the uncontrolled growth of abnormal white blood cells. These cells circulate throughout the bloodstream, crowding out healthy blood cells and interfering with the body’s ability to fight infections, transport oxygen, and clot blood properly.

There are different types of leukemia, such as acute lymphoblastic leukemia (ALL), acute myeloid leukemia (AML), chronic lymphocytic leukemia (CLL), and chronic myeloid leukemia (CML). Symptoms often include persistent fatigue, frequent infections, fever, unexplained bruising, and anemia.

In contrast, the other options listed are solid tumor cancers:

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  Metastatic breast cancer originates in the breast but can spread (metastasize) to other organs, forming tumors elsewhere.

  
  


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  Lung cancer typically forms a mass in the lungs.

  
  


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  Bladder cancer produces tumors within the bladder lining.

  
  

Leukemia is unique because it affects the circulatory system rather than forming localized growths. This makes detection and treatment different compared to solid tumors. Treatments often include chemotherapy, targeted therapy, immunotherapy, and bone marrow transplants.

In summary, the correct answer is Leukemia, the type of cancer that does not form a tumor but instead causes abnormal proliferation of white blood cells in the bloodstream and bone marrow.