Which technique is commonly used for the early detection of cancers through the examination of stained tissue sections under a microscope?
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → Biopsy
Cancer is found early by studying the suspected tissue itself. In a biopsy, a piece of the suspected tissue is taken out and cut into thin sections. The sections are stained and examined under a microscope by a pathologist. This study of tissue is called histopathology.
Option (1) Biopsy — Correct. Biopsy takes a piece of tissue, and its stained sections are examined under a microscope.
Option (2) Radiography — Incorrect. Radiography uses X-rays to take pictures of internal organs. It shows the inside of the body without taking out any tissue, so no stained sections are made.
Option (3) CT scan — Incorrect. A CT (computed tomography) scan uses X-rays to build a three-dimensional image of the internal organs. It is an imaging method, not a study of tissue under a microscope.
Option (4) MRI — Incorrect. MRI (magnetic resonance imaging) uses strong magnetic fields and non-ionising radiation to show changes in living tissue. It is also an imaging method and needs no tissue sample.
NCERT Extract:
Cancer – “… Cancer detection and diagnosis : Early detection of cancers is essential as it allows the disease to be treated successfully in many cases. Cancer detection is based on biopsy and histopathological studies of the tissue and blood and bone marrow tests for increased cell counts in the case of leukemias. In biopsy, a piece of the suspected tissue cut into thin sections is stained and examined under microscope (histopathological studies) by a pathologist. Techniques like radiography (use of X-rays), CT (computed tomography) and MRI (magnetic resonance imaging) are very useful to detect cancers of the internal organs.”