The NIH estimates that 2 million Americans will be diagnosed with cancer in 2025. Nearly half of all new cases will involve breast, lung, prostate, or colorectal cancers. Similarly, lung, colorectal, pancreatic, and breast cancers account for almost 50% of all cancer-related deaths.

Dr. Paulien Moyaert, on her YouTube channel, explains that it’s not always the cancer itself that kills, but the side effects it triggers within the body. In a 3D simulation, she details how metastatic cancer—the most lethal form—can spread from a single cell to other organs, ultimately causing them to fail.

If cancer develops in the digestive system, it can block food absorption and waste elimination, potentially leading to fatal intestinal perforation. In the pancreas, cancer may cause the organ to digest itself, making pancreatic cancer one of the deadliest and most painful types.

Lung cancer may result in death by asphyxiation, while infection is the second leading cause of death in cancer patients. Cancer weakens the immune system, and chemotherapy further suppresses bone marrow, reducing the body’s ability to produce white blood cells.

When cancer infiltrates the bone marrow, it disrupts blood cell production, leading to anemia, infection risk, and uncontrolled bleeding. Cachexia, or severe muscle loss, affects nearly 50% of cancer patients and contributes to their decline.

Despite these challenges, the video—viewed over 6.6 million times—stresses that no cancer patient should die in pain, with effective treatments like morphine and opiates available for pain relief.