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How does a biopsy help pathologists diagnose abnormalities such as tumours?

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Tuberculosis — disease A doctor examining chest X-rays of patients infected with tuberculosis, which remains one of the world's deadliest diseases.

A biopsy is a definitive diagnostic procedure in which cells or tissues are removed from a patient to be examined, typically under a microscope, to determine if a tumour is benign or malignant.12

Pathologists use several methods to obtain these samples, such as needle aspiration, excision, or abrasion. Once collected, the tissue is often fixed, embedded in paraffin, and sliced into thin sections. These sections are stained to highlight cellular characteristics, allowing the pathologist to perform a detailed microscopic analysis.1

This process helps diagnose abnormalities by:
* Visualizing Architecture: Examining the structural organization of tissue to identify cancerous growth patterns.2
* Cellular Assessment: Analyzing individual cell features, which is particularly useful in fine-needle aspiration.2
* Advanced Testing: Utilizing electron microscopy, immunohistochemistry, or molecular techniques to detect specific antigens, mutations, or chromosomal abnormalities.2
* Surgical Guidance: Providing "frozen sections" during surgery to confirm if a tumor has been completely excised.12

By identifying the site of origin and microscopic appearance, pathologists provide the critical information necessary to determine a patient's prognosis and treatment plan.3