World Cancer Day 2023: Time to Recognize the Problem and Take Action

What Is Cancer?

Cancer develops when changes in normal cells produce uncontrolled abnormal growth, forming a lump called a tumor. This tumor formation applies to all cancers except leukemia, a blood cancer (see our detailed explanation of cancer).

Untreated tumors can grow and invade normal tissue or spread through blood and lymph to other body regions. They may affect digestive, nervous and circulatory systems or release hormones that alter bodily functions.

Cancers can be classified by their cell of origin into five main types:

• Carcinoma: Carcinomas can invade nearby tissues and organs and metastasize to lymph nodes and elsewhere. Common examples include breast, prostate, lung and colon cancer.
• Sarcoma: A malignant bone or soft-tissue tumor. Common forms include leiomyosarcoma, liposarcoma and osteosarcoma.
• Lymphoma and Myeloma: Lymphoma affects the lymphatic system, which circulates throughout the body, so it can arise anywhere. Myeloma begins in plasma cells, white blood cells producing infection-fighting antibodies. It may impair effective antibody production.
• Leukemia : Cancer of white blood cells and bone marrow, the tissue producing blood cells. Several subtypes exist; common ones include lymphocytic and chronic lymphocytic leukemia.
• Brain and Spinal Cord Cancers: Known as central nervous system cancers. Some are benign, while others grow and spread.

According to WHO, approximately 20 million new cases and 10 million deaths were reported in 2020, the year of the latest global statistics. The most common cancers in 2020 by new cases were:

• Breast (2.26 million);
• Lung (2.21 million);
• Colon and rectum (1.93 million);
• Prostate (1.41 million);
• Skin, excluding melanoma (1.20 million); and
• Stomach (1.09 million).

The commonest causes of cancer death in 2020 were:

• Lung (1.80 million);
• Colon and rectum (916 000);
• Liver (830 000);
• Stomach (769 000);
• Breast (685 000).

Approximately 400,000 children develop cancer annually. The commonest cancers vary between countries; cervical cancer is the most common in 23 countries.

What Causes Cancer?

Many factors may cause cancer. As with other diseases, most cancers result from exposure to several different causal factors.

Modifiable Risk Factors:

• Alcohol;
• Overweight or obesity;
• Diet and nutrition;
• Physical activity;
• Tobacco;
• Ionizing radiation;
• Workplace hazards;

Nonmodifiable Risk Factors:

• Age;
• Carcinogens occurring naturally, such as radon and arsenic;
• Genetics;
• The immune system.

What Are Cancer Symptoms?

The signs and symptoms of different cancers vary and depend on where the disease is located. Nevertheless, important symptoms and complaints to watch for include:

• Unusual lumps or swelling;
• Cough, breathlessness or difficulty swallowing;
• Changes in bowel habits;
• Unexpected bleeding;
• Unexplained weight loss;
• Extreme fatigue;
• Pain;
• A new mole or changes in an existing one;
• Urinary problems;
• Unusual breast changes;
• Loss of appetite and unintended weight loss;
• A wound or ulcer that does not heal;
• Heartburn or indigestion;
• Heavy night sweats.

A 3-Year Campaign

World Cancer Day 2022-2024 Theme: Close the Care Gap

World Cancer Day is more than a single day. This 3-year campaign was designed to inspire progress. A multiyear approach aims to build global awareness, greater impact, participation and opportunity.

2022 Slogan: Recognizing the Problem

The first year of Close the Care Gap focused on understanding and recognizing cancer care inequities worldwide: keeping an open mind, challenging assumptions and examining facts.

• Inequity in cancer care costs lives.
• People seeking cancer treatment face barriers at every turn.
• Income, education, geography and discrimination based on ethnicity, sex, sexual orientation, age, disability and lifestyle are among the factors affecting care.
• These gaps affect everyone, including you and your loved ones.
• These barriers are not set in stone. They can change.

2023 Slogan: Uniting Our Voices and Taking Action

As the campaign continues, we will celebrate real-world progress in many forms and use that momentum to drive the fight for equity.

"We will do more than spread the word: we will shout it from the rooftops, build stronger alliances and create innovative collaborations."

Actions can take countless forms, from neighbors driving someone to a cancer center to ensuring healthy, affordable food choices in public schools.

2024 Slogan: Together, We Challenge Those in Power

The final year raises attention to a higher level. It will amplify voices to engage leaders in confronting inequity and create fully equipped, lifelong advocates demanding lasting change.

"Together, we will make sure leaders know we demand their commitment to prioritize cancer, develop innovative strategies addressing inequity, and invest resources in a fair, cancer-free world."