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How are X-rays used to help diagnose cancer?
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cancer
View through an endoscope of a polyp, a benign precancerous growth projecting from the inner lining of the colon.
X-rays are a vital diagnostic tool for identifying cancer by utilizing the differential absorption of radiation as it passes through body tissues. Because different structures absorb X-ray photons at varying intensities, these rays can reveal abnormalities, such as tumors, that might otherwise require exploratory surgery.12
Key diagnostic methods include:
- Standard X-rays: These provide images that differentiate between bone and soft tissue. To improve visibility of soft tissue abnormalities, physicians may use a contrast medium to enhance detail.2
- Mammography: This specialized procedure uses X-rays to detect breast lesions before they are palpable, which is critical for early diagnosis and improving survival rates.3
- Computed Tomography (CT): By rotating a narrow X-ray beam around the patient, CT scans generate high-resolution, cross-sectional images. This technique is far more sensitive to small density variations than conventional imaging, allowing for the precise location and monitoring of tumors and metastasis.123
While X-rays are essential for detection, a biopsy is typically required to confirm the presence of cancer.3