First joint guideline issued by Radiation Therapists and Urologists

Essential update: First joint guideline on prostate cancer therapy issued by ASTRO and AUA Medscape

For the first time in their history, the 2 medical organizations most responsible for the treatment of prostate cancer in the United States—the American Society for Radiation Oncology (ASTRO) and the American Urological Association (AUA)—have issued a joint guideline, a series of 9 major statements on the use of radiation therapy (either adjuvant or salvage) after prostatectomy. The statements are categorized as follows[1, 2] :

Clinical principles - Wide agreement by urologists
Recommendations - Grade C; low-quality and certainty evidence
Standards - Grade A or B; high/moderate-quality and certainty evidence
Options – Nondirectives
The guideline statements are as follows:

If a patient is undergoing radical prostatectomy for localized prostate cancer, discuss the possibility of adverse pathologic findings indicating an increased cancer recurrence risk (clinical principle)
If adverse pathologic signs—such as seminal vesicle invasion, positive surgical margins, and extraprostatic extension—are found, inform the patient that the risk for biochemical (prostate-specific antigen [PSA]) recurrence, local recurrence, or clinical progression of cancer is lower following a combination of radical prostatectomy and adjuvant radiation therapy than it is after radical prostatectomy alone (clinical principle)
If adverse pathologic signs are found at prostatectomy, offer adjuvant radiation therapy to the patient (standard; evidence strength, grade A)
Inform patients that PSA recurrence after surgery is associated with a higher risk for metastatic prostate cancer and with an increased mortality risk (clinical principle)
Biochemical recurrence should be defined as a detectable or rising postsurgery PSA value of at least 0.2 ng/mL, with a second confirmatory level of at least 0.2 ng/mL (recommendation; evidence strength, grade C)
A restaging evaluation should be considered in patients with a PSA recurrence (option; evidence strength, grade C)
Offer salvage radiation therapy to patients who, after radical prostatectomy, demonstrate PSA or local recurrence but have no distant metastatic disease (recommendation; evidence strength, grade C)
Inform patients that radiation therapy is most effective against PSA recurrence when PSA levels are relatively low (clinical principle).
Inform patients that radiation therapy may cause short- or long-term urinary, bowel, and sexual adverse effects, but also discuss the treatment’s potential benefits as a means of controlling disease recurrence (clinical principle).

Conventional EBRT
Conventional EBRT is typically delivered by means of a 4-field technique. The 4 fields (anteroposterior [AP], posteroanterior [PA], left lateral, and right lateral) are designed to include the prostate, the seminal vesicles, and the regional lymphatic vessels.


The morbidity of radiation treatment is intimately linked to the volume of normal tissue treated. Conventional radiotherapy includes irradiation of large volumes of tissue, including the skin, small bowel, bladder, large bowel, pelvic bones, and additional areas of soft tissue.

3-Dimensional conformal radiotherapy
In 3-dimensional conformal radiotherapy (3D-CRT), the radiation beam is shaped to include the 3D anatomic configuration of the prostate and any specified adjacent tissue (including the seminal vesicles and periprostatic adventitial tissues). This technique allows more precise delivery of therapy to the target organ or organs.

Intensity-modulated radiation therapy
Intensity-modulated radiation therapy (IMRT) can achieve tightly conformal dose distributions with the use of nonuniform radiation beams. The intent of this form of therapy is to create highly conformal fields by treating the patient with multiple static portals (so-called step-and-shoot IMRT) or dynamic fields. In dynamic IMRT, a series of arcs are administered through the area of interest. Multileaf collimators (MLCs) are reshaped many times as the machine performs a series of arc rotations around the target.

Image-guided radiotherapy
The term image-guided radiotherapy (IGRT) refers to the use of imaging techniques, including the following, in an attempt to ensure proper target localization during the course of radiotherapy:

Interfractional assessment (static) [3]
Portal imaging - The implantation of radiopaque fiducial markers into the prostatic target allows a soft tissue target to be localized with portal imaging technology
Ultrasonography - Ultrasonographic images of the prostate are obtained on a daily basis to identify the gland’s relative position
Computed tomography (CT) scanning - The radiation used for therapy can also be used to generate a CT image [4]
Radiofrequency localization - Small radio transponders can be implanted in the prostate to facilitate patient setup
Proton beam therapy
In contrast to photon beam therapy, the entrance radiation dose in proton beam therapy tends to be significantly less than the maximum energy of the clinical beam. Proton beams have a characteristic Bragg peak. Beyond this point, where energy is at a maximum intensity level, radiation energy rapidly falls off, which is important in the management of normal tissue toxicity.

Tomotherapy
Tomotherapy consists of helical radiotherapy using a computed tomography (CT)-like gantry and a rotating radiation beam that passes through the target area of interest; this modality has been used in the management of primary central nervous system tumors and viscera-based malignancies.

Hypofractionated radiotherapy
In this form of therapy, radiation is delivered from an accelerator, with the equipment mounted to a computer-guided robotic arm; because the machine is capable of treating the target at angles that are not possible with conventional rotation-based equipment, it yields the theoretical advantage of conforming the dose more closely to the target organ’s shape

Radiotherapy and androgen ablation
Data from the Radiation Therapy Oncology Group (RTOG) have shown a clear improvement in biochemical control of disease when patients receive a combination of radiotherapy and androgen-suppressive treatment. The results of several phase III clinical trials suggest that the true benefit of combining radiotherapy with androgen blockade may lie in the potentially synergistic effects of the 2 treatments.

Adjunctive EBRT
Combined prostate implantation and EBRT

A comprehensive literature review indicated that for high-risk patients, combination therapies involving EBRT and brachytherapy with or without androgen deprivation therapy appear to be superior to more localized treatments, such as seed implant alone, surgery alone, or EBRT.[5]

EBRT after radical prostatectomy

Multi-institutional data from the American Society of Therapeutic Radiation Oncology (ASTRO) consensus conference suggest that in patients treated for a rising PSA level, postoperative radiotherapy (typically in a dose range of 60-65 Gy) offers a PSA remission rate of 70%. Unfortunately, the durability of this response varies widely from center to center, with averages ranging from 25 to 67 months.