The 19th century saw the birth of scientific oncology with use of the modern microscope in studying diseased tissues. Rudolf Virchow, often called the founder of cellular pathology, provided the scientific basis for the modern pathologic study of cancer. As Morgagni had linked autopsy findings seen with the unaided eye with the clinical course of illness, so Virchow correlated microscopic pathology to illness.
This method not only allowed a better understanding of the damage cancer had done, but also aided the development of cancer surgery. Body tissues removed by the surgeon could now be examined and a precise diagnosis could be made. The pathologist could also tell the surgeon whether the operation had completely removed the cancer.
The precise origins of cancer have been a source of debate due, in part, to the scarcity of historical evidence. Possibly the earliest reference to the disease is attributed to the great Egyptian physician Imhotep, who lived around B. The likely reason that cancer is a relative newcomer in the historical record is that it most commonly afflicts those 65 and older, and for a long time, few people lived long enough for cancer to become a concern. Evidence for cancer has also been elusive in the fossil record, which preserves only a miniscule fraction of the bones of individuals who lived at any given time.
Some researchers have sought answers in mummified bodies, where they could study preserved soft tissue. In , for instance, autopsies performed on thousand-year-old mummies in Peru revealed at least one case of a woman in her mids with a malignant tumor in her upper-left arm. The mass had grown so large that it likely burst through her skin while she was still alive. The practice of mummification only goes back a few thousand years, while the fossil record goes back millions.
Now, Odes and his colleagues are highly confident that the hominin bone found at the Swartkrans site near Johannesburg holds the oldest known case of malignant cancer. Images recorded the density differences within the bone and generated views of the fragment from all directions. The abnormal growth pattern of bone tissue—including a distinctive, cauliflower-like external appearance—led the team to diagnose the condition as osteosarcoma, which today afflicts mostly children and young adults.
The fossil, a fragment of a toe bone from the left foot, is the only part of the skeleton that was found. It preserved too little information to determine which hominin species it belonged to, whether it was an adult or a child, or even if the cancer was the ultimate cause of death. In addition to the toe with the malignant growth, the team analyzed another, even older fossil with a tumor, albeit a benign one. In another study in the same journal , the team describes a growth in a vertebrae from a 1.
Prior to this discovery, the oldest known benign growth was in the ,year-old rib of a Neanderthal, excavated in Croatia. The scientists see the benign tumor found at Malapa as further supporting evidence for the existence of malignant cancer among our early relations. Randolph-Quinney, one of the investigating scientists. Whereas cancer is the extension of that growth process without the control mechanisms.
The team also sees their findings as an important reminder that cancer is a moving target. This cancer most often occurs in elderly and middle-aged adults. It's rare in children. It tends to grow locally, but sometimes it can spread to distant parts of the body, like the lungs. Fibrosarcoma is another type of cancer that develops more often in soft tissues than it does in bones. It usually occurs in middle-aged adults. Bones in the legs, arms, and jaw are most often affected.
This type of primary bone tumor can be either benign not cancer or malignant. The benign form is more common. These tumors are most common in people in their 20s and 30s. Giant cell bone tumors typically affect the legs usually near the knees or arms. With each recurrence, the tumor becomes a bit more likely to spread to other parts of the body most often to the lungs.
Rarely, a malignant giant cell bone tumor spreads to other parts of the body without first recurring locally. This uncommon type of bone tumor occurs in the bones of the spine, most often at the bottom of the spine sacrum or the base of the skull. It develops most often in adults older than It's about twice as common in men as in women. Rarely it can develop in children, as well.
Chordomas tend to grow slowly and often do not spread to other parts of the body. They often come back in the same area if they are not removed completely. If they do spread, they most often go to the lymph nodes, lungs, or liver. Some tumors that start in the bones are benign not cancer. Benign tumors do not spread to other parts of the body and are not usually life threatening. When they need to be treated they often can be cured with surgery.
Types of benign bone tumors include:. Some other cancers develop in the bones, but they don't start in the actual bone cells. These cancers start in early forms of blood cells or immune cells in the bone marrow the soft inner part of some bones. These are not considered to be primary bone cancers, and they are discussed in more detail elsewhere. In multiple myeloma, many tumors develop in the bones, but it's not a primary bone cancer because it starts in plasma cells a type of immune cell in the bone marrow.
Sometimes, myeloma can be found as a single tumor called a plasmacytoma in a bone, but most often it has spread to other bones, so it's treated as a widespread disease.
For more on this type of cancer, see Multiple Myeloma. Leukemias start in the blood-forming cells of the bone marrow, not in the bone itself. There are many types of leukemia. Most of these are cancers of early forms of white blood cells, but they can also start in other types of blood cells.
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