What is the purpose of tumor markers in oncology?

The purpose of tumor markers in oncology is primarily to aid in diagnosis, monitor treatment responses, and detect any potential recurrence of cancer. Tumor markers are substances, often proteins, that are produced either by the cancer cells themselves or by the body in response to the presence of cancer. Their presence or levels can provide valuable information to healthcare providers regarding the type and extent of cancer a patient may have, as well as how well treatment is working over time.

For instance, certain markers can indicate how aggressively a tumor is growing or whether it is responding to treatment, allowing for timely adjustments to a patient's treatment plan. Moreover, after treatment, measuring tumor marker levels can help in the early detection of recurrence, which is crucial for improving patient outcomes.

Thus, the utility of tumor markers directly supports clinical practices in oncology, contrasting with the other options which do not align with the roles of tumor markers in cancer assessment and management.