cancer

Table of Contents

Introduction & Top Questions
Malignant tumors and benign tumors
Tumor nomenclature
- Nomenclature of benign tumors
- Nomenclature of malignant tumors
- Site of origin
Cancer rates and trends
- Statistical records
- Preventable cancers
- Cancer and age
- Death rates
- Variation with region and culture
- Exposure to carcinogens and disease
The growth and spread of cancer
- Tumor progression: the clinical view
  - Presentation
  - Precancerous stage
  - The noninvasive stage
  - Invasion and dissemination
- Metastasis: the cellular view
  - Angiogenesis
  - Microinvasion
  - Dissemination
- Effects of tumors on the individual
  - Local effects of tumor growth
    - Effects of location
    - Effects of functional activity
    - Effects of acute events
  - Systemic effects of malignant tumors
- The immune response to tumors
  - Immune surveillance
  - Tumor antigens
    - Tumor-specific antigens
    - Tumor-associated antigens
Diagnosis and treatment of cancer
- Diagnostic procedures
  - Biopsy
  - Evaluation of tumors
    - Grading and staging
    - Molecular evaluation
- Therapeutic strategies
  - Conventional therapies
    - Surgery
    - Radiation therapy
    - Chemotherapy
    - Bone marrow transplantation
  - Targeted therapies
  - Angiogenesis inhibitors
  - Immunotherapy
  - Gene therapy
- Strategies for cancer prevention
  - Chemoprevention
  - Screening and early detection
Causes of cancer
- The molecular basis of cancer
  - Genetic and epigenetic programs
  - Hallmarks of cancer cells
  - The role of mutation
  - Oncogenes
    - Retroviruses and the discovery of oncogenes
    - Proto-oncogenes and the cell cycle
    - From proto-oncogenes to oncogenes
      Chromosomal translocation
      Gene amplification
      Point mutation
  - Tumor suppressor genes
    - The RB and p53 genes
      Discovery of the first tumor suppressor gene
      Loss of function of the RB protein
      The p53 gene
    - Other tumor suppressor genes
  - DNA repair defects
  - Apoptosis and cancer development
  - Telomeres and the immortal cell
  - Cancer stem cells
- Invasion and metastasis
- Cancer-causing agents
  - Oncogenic viruses
    - DNA viruses
      Human papillomaviruses
      Epstein-Barr virus
      Hepatitis B virus
    - RNA viruses
  - Chemicals, particulate matter, and fibers
    - Initiators
    - Promoters
  - Radiation
    - Ultraviolet radiation
    - Ionizing radiation
- Inherited susceptibility to cancer
  - Familial cancer syndromes
  - Syndromes resulting from inherited defects in DNA repair mechanisms
Milestones in cancer science

References & Edit History Quick Facts & Related Topics

Images & Videos

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For Students

cancer summary

cancer

Q: What characterizes cancer as a disease?

Cancer is characterized by the uncontrolled growth of abnormal cells in the body, which arises from malfunctions in the regulatory mechanisms that oversee the cells’ growth and development.

Q: What are the two major categories of tumors?

Tumors are divided into malignant (cancerous) and benign categories. Benign tumors remain localized to the area in which they originated and pose little risk to health. Malignant tumors grow and spread aggressively.

Q: How can the global cancer burden be reduced?

The global cancer burden could be reduced by 30 to 50 percent through prevention strategies, particularly avoiding known risk factors.

disease

Also known as: malignant neoplasm

Written by José Costa

Fact-checked by The Editors of Encyclopaedia Britannica

Last Updated: Jan 7, 2025 • Article History

Key People:: Gregg L. Semenza; Tasuku Honjo; Peter J. Ratcliffe; James P. Allison; Gregory P. Winter

Related Topics:: pancreatic cancer; breast cancer; prostate cancer; colorectal cancer; lung cancer

See all related content

What characterizes cancer as a disease?

What are the two major categories of tumors?

How can the global cancer burden be reduced?

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cancer, group of more than 100 distinct diseases characterized by the uncontrolled growth of abnormal cells in the body. Though cancer has been known since antiquity, some of the most significant advances in scientists’ understanding of it have been made since the middle of the 20th century. Those advances led to major improvements in cancer treatment, mainly through the development of methods for timely and accurate diagnosis, selective surgery, radiation therapy, chemotherapeutic drugs, and targeted therapies (agents designed against specific molecules involved in cancer). Advances in treatment have succeeded in bringing about a decrease in cancer deaths, though mainly in ...(100 of 22022 words)

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