A Brief History of Cancer

When was cancer discovered?

Cancer has affected animals for millions of years. Scientists have found cancer in dinosaur bones from 70 to 80 million years ago.

The earliest signs of cancer in humans were tumors found in fossilized bones and mummies from 3000 BCE in ancient Egypt. The oldest written description of cancer is found in the Edwin Smith Papyrus from 3000 BCE. It was described as a “bulging tumor of the breast.”

Hippocrates was a Greek doctor who lived from 460–370 BCE. He was the first person to use the word “cancer” in his writings. He used the Greek terms for crab – carcinos and carcinoma – to describe a tumor because it looked like a moving crab.

Hundreds of years later, a Roman doctor named Celsus, who lived from 25 BCE–50 CE, translated the Greek terms into the Latin word cancer.

Galen, a Greek doctor who lived from 130–200 CE, was the first to use the word oncos (Greek for swelling) to describe tumors. This is where we get the words oncologist and oncology.

Early theories about cancer

For thousands of years, people have tried to figure out what causes cancer. In ancient Egypt, getting cancer was blamed on the gods. Hippocrates thought cancer developed because a person’s body fluids were out of balance.

From the 1500s through the 1700s, scientists had many ideas about what causes cancer. They thought cancer formed because of lymph fluid problems, chronic inflammation, injury, or an infection passed from person to person.

Setting the groundwork for modern oncology

It took some major advances for scientists to gain a better understanding of cancer.

Invention of pathology and the microscope

An Italian doctor named Giovanni Morgagni was a pioneer in the field of pathology. He did the first autopsies in 1761. He described what he saw in a person’s body after death, often linking a person’s illness to their cause of death. These reports led to what’s known as scientific oncology, or cancer research.

In the 1800s, the modern microscope was developed. This led to several discoveries, such as:

• Cancer is made up of cells.
• All cells, including cancer cells, come from other cells.
• Cancer cells look different from normal cells under the microscope.

These discoveries led scientists to study how cancer cells act and how molecular changes determine how cancer cells behave.

Additionally, using the microscope, pathologists could look at body tissues removed during surgery to diagnose cancer. They could also tell surgeons whether they had completely removed the cancer.

All these findings have advanced the fields of oncology, pathology, molecular biology, and epidemiology. Studies in these fields have led to better early cancer detection and more effective treatments.

Field of epidemiology 

During the 1700s, two key observations launched cancer epidemiology.

In 1713, an Italian doctor named Bernardino Ramazzini connected certain jobs to different diseases. He noted that women who were nuns rarely got cervical cancer and had high rates of breast cancer. He wondered if there was a link to their lifestyle, celibacy, and not having children. This led to a greater understanding of the role of hormones and sexually transmitted diseases in cancer.

In 1775, a British surgeon named Percival Pott described how soot exposure could cause scrotal cancer in men working as chimney sweeps. This led to further study of how certain occupational exposures may cause cancer.

In 1971, the National Cancer Act led to the creation of a network of cancer registries to track cancer data. It also set up the Surveillance, Epidemiology, and End Results (SEER) Program to track cancer rates and survival.

Carcinogens

Research has identified many factors that can cause cancer (carcinogens). Here are some examples of major breakthroughs in cancer causes:

• In 1761, tobacco use was linked to cancer.
• In 1911, a virus that caused cancer in chickens was found. This research helped show that several viruses are linked to cancer in humans. Researchers linked hepatitis B virus (HBV) with liver cancer and the Epstein-Barr virus (EBV) with non-Hodgkin lymphoma.
• In the 1980s, the bacteria H. pylori was shown to increase the risk of stomach cancer.
• In 1991, research showed that DNA damage in cells can happen from certain exposures in the environment. As a result, the cells can be more sensitive to carcinogens, such as UV radiation and cigarette smoke.
• In 1999, human papillomavirus (HPV) was shown to be present in 99.7% of cervical cancers. This led to the development of the HPV vaccine to prevent cervical cancer in 2006.

DNA changes, oncogenes, and tumor suppressor genes

By the mid-20th century, breakthroughs in molecular biology were milestones in cancer research. One example is the discovery of DNA’s structure, which revealed how changes (mutations) in a cell’s genes lead to cancer. These changes could be inherited or caused by carcinogens in a person’s environment. They also found that cancer cells with damaged DNA do not die, unlike normal cells.

In the 1970s, scientists identified oncogenes and tumor suppressor genes. Mutations in these genes can lead to cancer. For example, BRCA1 and BRCA2 are inherited mutations that increase breast and ovarian cancer risk. At the time, other inherited mutations were linked to colon, kidney, ovary, thyroid, pancreas, and skin cancers.

The completion of the Human Genome Project in 2000 helped researchers identify more gene mutations in people with cancer. This helped develop more effective cancer treatments.

Understanding how cancer can be found early

Screening tests help find cancer in people without symptoms. Regular screening increases the chances of finding certain cancers early, before cancer has a chance to spread. Some screening tests, like those for cervical and colorectal cancer, can find abnormal growths before they become cancer. Removing these pre-cancerous growths can help prevent cancer.

The first widely used screening test was the Pap test for cervical cancer. It was developed in the 1920s. The Pap test helped decrease cervical cancer rates by more than half through early detection and treatment. Pap tests are still sometimes used to help find cervical cancer today. However, the discovery of human papillomavirus (HPV) as a cause of most cervical cancers led to guidelines recommending the use of a primary HPV test with or without a Pap test.

The mammogram was developed in the 1960s and remains the most reliable way to screen for breast cancer.

There continue to be advancements in cancer screening. Colonoscopy and stool-based tests are used to detect colorectal cancer, and low-dose CT scans of the chest are used to screen for lung cancer in those at increased risk.

Multi-cancer early detection (MCED) tests are a new type of lab test that looks for signs of many types of cancer in the blood and other body fluids. Some of these tests are available but are expensive and not yet FDA-approved. 

Brief history of cancer treatment

Cancer treatment has changed and improved over time. Below is an overview of the history of the most common types of cancer treatment.

Surgery and anesthesia

In ancient times, surgery was very crude and caused many problems. Without anesthesia or an understanding of infection, operations often did more harm than good. The Greek physician Galen (130–200 CE) thought cancer could not be cured because surgical options were limited.

That belief held for centuries until 1846, when effective anesthesia transformed what surgeons could do. Tumors and lymph nodes could be removed more completely and safely. By the late 1800s, the radical mastectomy was developed to treat breast cancer, though it would take another century to show that breast-conserving surgery could work just as well.

As technology advanced through the 1900s, surgical precision improved further: limbs were spared, breasts preserved, and incisions made ever smaller. Today, imaging tests like CT, MRI, and PET scans allow surgeons to locate tumors without surgery, and robotic systems allow them to operate on some patients through openings barely larger than a keyhole.

Hormone therapy

Early cancer surgeries also paved the path for new treatment methods. As far back as 1895, removing the ovaries (oophorectomy) was shown to slow breast cancer, hinting at the disease’s dependence on estrogen. This led to the development of hormone therapy.

In 1977, the FDA approved tamoxifen, which is a medicine that blocks hormone activity without the need for surgery. The same logic guided prostate cancer treatment: surgical castration in the 1940s gave way to medicines that suppress or block male hormones.

Radiation therapy

While surgery was the first line of defense, other breakthroughs followed. The discovery of x-rays in 1895 led to radiation therapy, which was soon used for cancer treatment.

Early forms of brachytherapy (internal radiation) were first used in the early 1900s to treat cervical and prostate cancers. At the same time, external beam radiotherapy was being developed and improved to increase effectiveness and decrease side effects. Proton beams, introduced in the 1960s, offered even greater precision. Further advances in the 1990s helped reduce damage to healthy tissue through methods like conformal and intensity-modulated radiation therapy.

Chemotherapy

Another effective treatment against cancer came from the military. Researchers studying chemical agents found that nitrogen mustard could shrink lymphoma tumors, and it was approved for treatment in 1949. This finding was the birth of chemotherapy (chemo).

Soon after, medicines like aminopterin and methotrexate were shown to treat childhood leukemia. By the 1960s and 1970s, chemotherapy was leading to cures for Hodgkin disease, childhood ALL (acute lymphoblastic leukemia), and testicular cancer. Today, new chemo medicines, combinations of chemo, and new ways to give these medicines have made chemo more effective and helped reduce side effects.

Stem cell and bone marrow transplants

The toxic effects of radiation and chemotherapy on bone marrow led to another major advance: stem cell and bone marrow transplants. First performed in 1957, these procedures put healthy blood stem cells back into a person’s body after their bone marrow has been destroyed by disease, chemotherapy, or radiation treatments. Improvements in genetics and immune science have since reduced stem cell rejection and side effects, making transplants a key part of treatment for blood cancers.

Immunotherapy and precision medicine

Throughout the 1900s, advances in cellular biology provided new options for cancer treatment. In the 1980s, researchers began designing targeted therapies, or medicines that block certain functions that cancer cells use to grow and spread. The first, trastuzumab, approved in 1998, blocks the HER2 protein, which is a biomarker that drives the growth of some breast cancers. Two decades later, pembrolizumab became the first treatment approved to target a tumor’s genetic changes rather than where it began. This was an important step toward fully personalized care.

Around the same time, scientists were learning about how the immune system fights cancer. Immunotherapy, or therapies that help the immune system detect and get rid of cancer, became a reality with the approval of interferons to treat hairy cell leukemia in 1986. A wave of discoveries followed: BCG for some bladder cancers, interleukins for kidney cancer, monoclonal antibodies like rituximab for lymphoma, cancer vaccines for prostate cancer, and checkpoint inhibitors for melanoma skin cancer. More recently, cell-based therapies have been developed, like CAR T-cell therapy for certain blood cancers and TIL therapy for some solid tumors.

Today, precision medicine ties all these treatments together. By analyzing the genes and proteins in a person’s tumor or blood, doctors can choose treatments that are most likely to be effective against their cancer.

Understanding cancer survivorship

As of 2022, more than 18 million cancer survivors were living in the US. This number is expected to exceed 22 million by 2035. All these cancer survivors have unique needs for follow-up care, late and long-term side effects, and mental health support.

To help address the needs of cancer survivors, the National Coalition for Cancer Survivorship (now Cancer Nation) was founded in 1986. The organization supports research about cancer survivorship and people diagnosed with cancer at all points in their cancer journey.

In 1996, the Office of Cancer Survivorship (OCS) was created as part of the National Cancer Institute (NCI) to help increase knowledge and promote research about how to manage the long-lasting effects experienced by cancer survivors.

In 2006, the Institute of Medicine (now the National Academy of Medicine) released a report on cancer survivorship called From Cancer Patient to Cancer Survivor: Lost in Transition. The report emphasized the need for an effective transition plan to support the long-term health of cancer survivors, especially when making the transition from active treatment to post-treatment. It outlined the needs of cancer survivors and called for better coordination of care between the cancer care team and primary care providers.

What the future of cancer research holds

Cancer research continues to find new ways to prevent, detect, and treat cancer and meet the needs of cancer survivors. Research is also looking at cancer outcomes for different groups of people and improving access to cancer care. Some examples of current research are:

• Physical activity and inactivity can affect the risk of some cancers.
• New ways to calculate breast cancer risk can help personalize prevention and screening.
• Inadequate health insurance can affect cancer survival.
• New gene testing tools may personalize ovarian cancer care.

The possibilities of what might be accomplished through research and other  developments excite patients and researchers alike and allow for a more hopeful picture for cancer survivors and those who get cancer in the future.