Introduction to Cancer: Causes and Types

Cancer Overview

• Cancer is a group of diseases characterized by uncontrolled cell growth.
• It arises from failures in mechanisms controlling cell division, growth, and death.
• Uncontrolled abnormal cell growth forms tumors, which can be benign (non-cancerous) or malignant (cancerous).
• Malignant tumors invade surrounding tissues and may metastasize (spread) to other body parts.
• Cancers vary based on tissue/organ origin, including lung, breast, colon, and leukemia.
• Cancer encompasses diverse diseases with differing causes, characteristics, and treatments.

Causes of Cancer

• Genetic mutations (inherited or acquired) increase cancer risk.
• Exposure to carcinogens (chemicals, radiation, certain viruses) contributes to cancer.
• Lifestyle factors (smoking, diet, inactivity, obesity) elevate cancer risk.
• Certain chronic infections increase cancer risk in some populations.

Types of Cancer and Development

• Cancer development is a multi-step process, often involving multiple genetic mutations over many years.
• Different cancers have varying properties regarding cell origin, growth rate, and treatment response.
• Some cancers progress slowly, others rapidly.
• Specific mutations cause uncontrolled cell growth/division, beginning tumor formation.

Tumor Characteristics

• Benign tumors are typically encapsulated and do not invade other tissues. They can cause issues if they grow large and compress organs/vessels.
• Malignant tumors lack encapsulation, are invasive, exhibiting abnormal cell shapes, faster growth, and unusual behaviors.
• Metastasis, the spread of cancerous cells to distant sites via the circulatory or lymphatic systems, is a hallmark of malignant tumors.

Cancer Diagnosis

• Diagnosis uses a combination of physical exams, imaging (X-rays, CT, MRI), biopsies, and blood tests.
• Blood tests (like complete blood counts) provide information regarding cancer progression, treatment response, and overall impact on the body.

Cancer Treatment

• Treatment options depend on the cancer type, stage, patient's health, and choose from various options, including surgery, radiation, chemotherapy, targeted therapies, immunotherapy, and hormone therapy.
• The goal is to remove/destroy cancer cells, shrink tumors, reduce spread, manage symptoms, and improve quality of life.

Cancer Prevention

• A healthy lifestyle (balanced diet, regular exercise, avoiding tobacco) reduces cancer risk.
• Regular screenings (e.g., mammograms, colonoscopies) detect cancer early, improving treatment outcomes.
• Reduced exposure to known carcinogens is essential for prevention.