Utilizing PET/CT when Planning for External Radiation Therapy for Prostate Cancer

Localized prostate cancer patients are treated with radiotherapy and prostatectomy. After radical prostatectomy, a patient may still experience an increase in the level of prostate-specific antigen, an indication of the recurrence of prostate cancer. When this happens, the patient undergoes radiotherapy to cure the prostate cancer recurrence. To maximize the chances of curing the recurrent prostate cancer, irradiated volumes should surround the extent of the disease.

Accurate estimation of the disease location is critical for radiotherapy planning in both salvage and definitive settings. The current first-line imaging for prostate cancer has limited sensitivity for detecting disease at biochemical recurrence and initial staging. Integrating PET into the routine evaluation of patients with prostate cancer can improve both the radiotherapy planning and the staging accuracy. 18F-FDG PET/CT has low sensitivity and is now used routinely in radiation planning for several types of cancer.

Experts have concluded that radiation therapy based on PET/CT is more accurate compared to other standard methods in these cases:

• Imaging of lesions that are not apparent TO MRI or CT such as distant metastases or unsuspected lymph nodes.
• Preventing irradiation of tissues that don’t contain tumor cells.
• When chemotherapy is added to radiation therapy, the response can be assessed better with PET/CT.
• Development of response-adapted therapy where changes to target volumes could be made during a course of treatment.

PET/CT is under study as a replacement of conventional imaging techniques especially in IMRT planning which allows delivery of non-homogeneous dose and non-uniform radiation distribution within the target volume.

About Author

PET / CT of Las Colinas was developed with both patients and physicians in mind and our services have been used for various types of disease; primarily in detecting, staging and monitoring cancer, but also in heart disease and brain disorders.

PET / CT of Las Colinas employs PET / Positron Emission Tomography. PET is a powerful imaging technique that holds great promise in the diagnosis and treatment of many diseases, particularly cancer.