Surgery is a common and often essential treatment for many types of cancer, aiming to remove tumors and affected tissues. However, a question that frequently arises is whether surgery itself can cause cancer cells to spread, potentially worsening the disease. Understanding this concern requires exploring how cancer spreads, what happens during surgery, and the biological behavior of cancer cells.
Cancer spreads through a process called metastasis, where cancer cells break away from the original tumor, travel through the bloodstream or lymphatic system, and establish new tumors in other parts of the body. This process involves several complex steps: cancer cells must detach from the primary tumor, invade surrounding tissues, enter blood or lymph vessels, survive the journey, exit into new tissues, and grow there. Cancer cells have special abilities that allow them to break down barriers that normally keep cells in place, such as producing enzymes that digest the extracellular matrix—the “glue” holding cells together—and evading cell death mechanisms. These abilities make metastasis a challenging problem in cancer treatment.
During surgery, the goal is to remove the tumor entirely along with some surrounding healthy tissue to ensure no cancer cells remain. Surgeons take great care to avoid spreading cancer cells during the procedure. However, it is biologically possible that manipulating the tumor could dislodge some cancer cells, which might then enter the bloodstream or lymphatic system. This theoretical risk has led to concerns that surgery could inadvertently promote metastasis.
Despite this possibility, extensive research and clinical experience show that surgery does not generally increase the risk of cancer spreading in a meaningful way. Several factors explain this:
– The body’s immune system and natural barriers often eliminate stray cancer cells that might be released during surgery.
– Surgical techniques have advanced to minimize tumor manipulation and reduce the chance of dislodging cells.
– Surgeons remove not only the tumor but also nearby lymph nodes and tissues that might harbor microscopic cancer cells, reducing the chance of residual disease.
– In many cases, surgery is combined with other treatments such as chemotherapy, radiation, or targeted therapies that help kill any cancer cells that might have escaped.
There are rare situations where surgery might be associated with increased risk of spreading, such as when tumors are very fragile or located in areas where cancer cells can easily enter circulation. In these cases, surgeons may use special precautions or alternative treatments. Additionally, some experimental studies in animals have suggested that surgery might temporarily suppress the immune system or trigger inflammatory responses that could facilitate cancer cell survival and spread. However, these effects are generally short-lived and do not outweigh the benefits of removing the tumor.
Another important aspect is the tumor microenvironment—the surrounding cells, blood vessels, immune cells, and molecules that interact with cancer cells. Surgery alters this environment, which might influence cancer cell behavior. For example, inflammation caused by surgery can release signals that promote healing but might also create conditions favorable for cancer cells to grow if any remain. Researchers are actively studying how to modulate this response to improve outcomes.
In summary, while the biology of cancer and the mechanics of surgery suggest a theoretical risk that surgery could spread cancer cells, clinical evidence overwhelmingly supports surgery as a safe and effective treatment. The benefits of removing the tumor and reducing cancer burden far exceed the minimal risk of spreading. Surgeons and oncologists use careful techniques and combined therapies to minimize any such risks. Understanding the complex interplay between cancer cells, the immune system, and surgical intervention continues to be an important area of research to further improve cancer treatment outcomes.
