Diagnosis of Cancer
A systematic process is used in cancer diagnosis in order to identify, validate, and assess the disease's severity. This include imaging examinations, biopsies, laboratory tests, and patient evaluation. For better results and efficient treatment, an early and precise diagnosis is essential.
1. Patient Evaluation:
A comprehensive clinical evaluation is the first stage in patient evaluation. A thorough medical history is taken first, with particular attention paid to symptoms including chronic exhaustion, unexplained weight loss, tumors, bleeding, or pain. In addition to lifestyle factors like alcohol or tobacco use and occupational exposures to possible carcinogens, family history is evaluated for genetic predispositions, such as BRCA mutations in breast cancer. After that comes a physical examination that includes palpation to find lumps or masses, neurological evaluations if brain or spinal tumors are suspected, and observation for changes in the skin, moles, or enlargement of organs. This all-encompassing method aids in directing subsequent diagnostic procedures.
2. Screening Tests:
In order to identify cancer early on, screening is done for at-risk asymptomatic patients. Common screening modalities are:
· Mammography: For breast cancer detection.
· Pap Smear and HPV Testing: For cervical cancer.
· Colonoscopy or Fecal Tests: For colorectal cancer.
· Low-Dose CT Scan: For lung cancer in high-risk groups (e.g., heavy smokers).
· Prostate-Specific Antigen (PSA) Test: For prostate cancer.
3. Imaging Tests:
Imaging is useful for identifying the location, size, and spread of tumors as well as for visualizing interior structures.
· X-rays: Initial imaging, e.g., chest X-rays for lung abnormalities.
· Ultrasound: Identifies cysts or solid masses (e.g., in breast or abdominal organs).
· Positron Emission Tomography (PET): Detects metabolic activity of cancer cells using radiotracers.
· Computed Tomography (CT): Provides detailed cross-sectional images.
· Magnetic Resonance Imaging (MRI): Superior for soft tissue imaging (e.g., brain, spinal cord).
· Bone Scans: Identify metastases to bones using radioactive tracers.
4. Laboratory Test:
Laboratory tests can confirm the diagnosis of cancer or reveal details about its biological activity.
Your doctor may perform laboratory testing, like blood and urine tests, to find anomalies that could be cancer-related. For example, a routine blood test known as a complete blood count may show an abnormally high or low quantity of white blood cells in individuals with leukemia.
5. Biopsy:
The gold standard for diagnosing cancer is a biopsy, which involves removing tissue and examining it under a microscope.
Your doctor takes a sample of cells during a biopsy so that they may be tested in a lab. There are various methods for gathering a sample. The type and location of your cancer will determine which biopsy approach is best for you. A biopsy is typically the only method that can provide a conclusive diagnosis of cancer.
Doctors examine cell samples under a microscope in the lab. Normal cells have a consistent appearance, comparable sizes, and a well-organized structure. Cancer cells are less structured, with different sizes and no discernible pattern.
Types of Biopsies:
· Needle Biopsy: Fine-Needle Aspiration (FNA): Extracts cells and Core Needle Biopsy: Extracts tissue samples.
· Incisional and Excisional Biopsies: Partial (incisional) or complete (excisional) tumor removal.
· Endoscopic Biopsy: Uses a flexible tube to visualize and collect tissue (e.g., for gastric or colon cancers).
· Bone Marrow Biopsy: For hematological cancers like leukemia or lymphoma.
· Liquid Biopsy: Detects circulating tumor cells (CTCs) or DNA in blood.
