The body's normal cells in different long-term effect of cancer-causing factors, the performance of the cells increased, but cell morphology has not changed. While the increase in the number, cell morphology and tissue of origin differences in cell morphology gradually increased, but not yet developed into cancer, the stage is a precursor stage of cancer, known as " precancerous lesions . "
Common clinical precancerous lesions are the following:
1. Leukoplakia: In order to place limitations on the new film, shiny and thick white spots. Occur in the lips, tongue, mouth, vulva occurred in a small number of teaching film, occur oral cancer and vulvar cancer risk.
2. Atrophic gastritis: atrophic gastritis to gastric cancer may develop 1.5910_3910's for atrophic gastritis patients should have regular endoscopy.
3. Cervix William Black: Black Lian female cervix, the cervical cancer incidence rate of cervical smooth than 2 times higher thousand. If suspected of having cervical cancer, colposcopy or cervical biopsy should be checked.
4. Cystic breast disease: The disease occurs mainly in 30_50 usually found in breast development between the ages of the smaller and more maternal, reproductive women can occur without the disease. Clinical features occur within the breast or multiple main round is hard swelling, and skin, muscle, fascia no adhesion can promote. Size rarely exceeds 3 cm. An average of 10% can develop into breast cancer.
5. Old solar keratoses: mainly in the face, arms and other exposed parts, there may develop into skin cancer.
6. Pigmented dry skin disease: light sensitivity for the autosomal recessive congenital hereditary diseases, often beginning at an early age the incidence of skin damage occurs mainly in exposed areas, the prognosis is good in small, often die of cancer, such as basal cell carcinoma, squamous cell carcinoma, malignant melanoma and other malignancies.
Clinical common precancerous lesions, 7. Jeghers: especially with familial polyposis of the colon, large intestine adenoma much longer, at least 100 or more, often after the age of 40, large intestine, this British adenoma occur due to colorectal carcinogenesis.