Prostate cancer occurs when certain cells within the prostate gland grow in an uncontrolled, abnormal, manner. The prostate gland is the male organ located next to the bladder that contributes to the production of semen.
A 67-year-old man with biochemical recurrence of prostate cancer. Axial PET (A) and axial fused PET/CT (B) images show intense localization of anti-18F-FACBC in metastatic left external iliac nodal basin (arrow). Axial SPECT (C) and axial fused PET/CT (D) demonstrate only low-grade activity on 111In-capromab pendetide scintigraphy.
The American Cancer Society estimated more than 240,000 new cases of prostate cancer will be diagnosed in the United States and nearly 40,000 men will die from the disease in 2011. Prostate cancer is the second leading cause of cancer death in American men, behind only lung cancer.
When detected early, prostate cancer has more than a 90 percent cure rate. Because treatment is highly individualized, molecular imaging technologies are dramatically improving the ways in which prostate cancer is diagnosed and treated.
Treatment options include surgery to remove the prostate, radiation therapy and chemotherapy, and more. Some men with low risk prostate cancer may choose to defer treatment and undergo Active Surveillance. Determining whether the prostate cancer has spread to the lymph nodes or other parts of the body is critical for making accurate decisions on whether and how to treat prostate cancer. In addition to improving the accuracy of a prostate cancer diagnosis, molecular imaging and nuclear medicine tools can provide detailed information about the cancer that help patients and their physicians choose the best treatment options.
Molecular imaging technologies most commonly used to diagnose and guide the treatment of prostate cancer currently include a bone scan (T-99 or F18 PET), the prostate-specific membrane antigen (PSMA) study and positron emission tomography (PET) scanning and PET in conjunction with computer-aided tomography (CT).
PET is a very sensitive technique for detecting cancer. In prostate cancer, fluciclovine PET has been approved for use in staging and restaging prostate cancer. Other agents, including PSMA are currently under investigation for these indications.
A bone scan is a diagnostic imaging test used to determine whether cancer has spread beyond the prostate to the skeleton. A tiny amount of radiotracer is injected into the patient’s bloodstream and accumulates predominantly in the bones where it can be detected by a specialized imaging device called a gamma camera. The resulting two-dimensional or three-dimensional images can reveal various processes such as bony fractures, infection, inflammation or the presence of prostate cancer cells.
Physicians use molecular imaging to:
This 73-year-old man was recently diagnosed with prostate cancer and has an elevated PSA. PET/CT shows the intense activity in the prostate cancer (arrow) and the spread to the left pelvic bone (b).
Scientists are working on new molecular imaging techniques that will:
Researchers across the country are hopeful about the many studies underway to determine how molecular imaging can improve the diagnosis, staging and treatment of prostate cancer. Molecular imaging is ideal for assessing the prostate gland; where other diagnostic imaging procedures visualize the structure of organs, molecular imaging allows physicians to detect cellular changes that occur early in the course of disease.
Using various molecular imaging technologies, scientists are looking for biological changes that occur as a result of cancer and in response to treatment. These indicators, called biomarkers, could provide an early warning sign for cancer or measure the body’s response to drug therapy. By studying both prostate cancer patients and men with a family history of the disease, researchers hope to identify biomarkers that can predict the progression of disease or a patient’s response to treatment.
To better image the many different forms of prostate cancer, scientists are also testing a variety of new radiotracers to use with PET. Researchers are also exploring applications for optical imaging, in which a light-producing protein literally illuminates the dark interiors of the body, and hybrid imaging, in which images produced by multiple technologies are fused together to provide a more comprehensive view.