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Tumor markers. Tumors. Benign tumors: e.g. moles, warts Malignant tumors: metastasis, called cancer. Tumor markers. CANCER: Loss of control of cellular growth NEOPLASIA: New growth TUMOUR: Swelling ONCOLOGY: Study of cancer CARCINOMA - epithelial cells SARCOMA - connective tissue
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Tumors • Benign tumors: e.g. moles, warts • Malignant tumors: metastasis, called cancer
Tumor markers • CANCER: Loss of control of cellular growth • NEOPLASIA: New growth • TUMOUR: Swelling • ONCOLOGY: Study of cancer • CARCINOMA - epithelial cells • SARCOMA - connective tissue • OSTEOMA - bones
Etiology of cancer • Multifactorial (Physical, Chemical, Genetic & Environmental) • chemical carcinogens • Radiating energy • Carcinogenic viruses • By any means DNA of host is affected
Molecular Basis of cancer • Activation of protooncogenes to oncogenes • Viral insertion into chromosome • Chromosomal translocation • Gene amplification • Point mutation
Tumor marker definition Biochemical substances synthesized & released by cancer cells or produced by host in response to cancerous substance.
Applications • Screening • Diagnosis • Prognosis • Classification • Monitoring response of therapy • Follow up-Recurrence
Characters of an ideal tumor marker • Analytical Criteria • High analytical sensitivity and specificity • Accuracy and Precision • Easy to measure at a low cost • Clinical Criteria • Disease sensitive (no false-negative results, ability to detect micrometastasis). • Disease specificity (no false-positive results, negative in disease-free individuals). • Associate only with particular cancer. • Levels should remain relatively constant and not fluctuate in patients with stable disease. • Correlate well with cure rate. • Should be undetectable or low in patients in complete remission.