Читать книгу Overcome the Challenges of Cancer Care - M. D. Rosenberg - Страница 13

Once a patient shows up with a red-flag symptom, doctors pursue a diagnostic workup.

A red flag prompts a doctor to do a more thorough investigation. This includes taking a comprehensive medical history and performing a physical exam. Doctors will often order some basic blood work. These tests look at whether the patient’s blood carries enough oxygen (based on the number of red blood cells), is able to fight infections (based on the number of white blood cells, which are the immune cells), and clots correctly (based on the number of platelets).

If doctors suspect a certain type of cancer, they may order a test for tumor markers. Tumor markers are proteins that leak out into the blood from tumors. We can then measure the levels of these proteins in the blood.

Most cancer markers are nonspecific. Therefore, they aren’t good for screening a population (people) for cancer (see the earlier section on cancer screenings); the markers may be elevated even when there is no cancer. But doctors may use tumor markers to narrow down the possible types of cancer if they suspect a certain cancer in a patient.