Diagnosing pre-malignant lesions before they evolve into true, potentially invasive cancers has many advantages - they cab be treated while still very small and cost and side effects of therapy are minimal. The cost of treatment of positive lesions is much less than that of treating malignant tumours and, depending upon circumstances can be treated in the patient's own village (or a location near-by. Unfortunately, not all cancers can be detected in a pre-malignant phase - in fact, very few present while still asymptomatic, and symptoms occur when the cancer has already become invasive. Two major exceptions to this are cervical cancer and mouth cancer, since these cancers can be souoght by simple and safe screening approaches which cost little, and if organized well, can lead to diagnosis at a time when simple excision or cryosurgery are adequate in the vast number of cases to remove all potentially malignant cells.
Cancer Prevention and Early Diagnosis