What does "complete remission" mean in cancer treatment?

"Complete remission" in cancer treatment refers to the absence of detectable evidence of the disease following treatment. This definition signifies that after various treatment modalities, such as chemotherapy, surgery, or radiation, thorough examinations—often including imaging studies and laboratory tests—indicate that there are no remaining cancer cells in the body.

This is a critical milestone in cancer therapy, moving beyond just reduction in tumor size or temporary improvement. While the reduction of a tumor (which could suggest a partial response) might be a step toward remission, it does not equate to complete remission, as some cancer cells may still be present and capable of regrowth. Similarly, the term "temporary improvement" does not capture the essence of remission, as it implies that the disease could return, whereas complete remission means a sustained absence of disease detectable by standard methods.

Full recovery from cancer is also a broader term that may imply living without cancer for a significant period, but it can be misunderstood, as complete remission might not guarantee that the cancer will not recur. Therefore, the definition of complete remission emphasizes the currently undetectable state of the disease, making "no detectable evidence of disease after treatment" the most accurate and precise description.