What pretreatment prostate-specific antigen level warrants long-term androgen deprivation?

Do Prostate Cancer Patients With Markedly Elevated PSA Benefit From Radiation Therapy?: A Population-based Study

OBJECTIVES

Patients with clinically localized prostate cancer but markedly elevated prostate-specific antigen (PSA) are often treated with systemic agents alone. We hypothesized that they would benefit from radiation therapy.

METHODS

We utilized the Survival, Epidemiology and End Results (SEER) Database for patients diagnosed with nonmetastatic prostate cancer from 2004 to 2008. Patients treated surgically or with brachytherapy were excluded. Survival was analyzed using the Kaplan-Meier method and Cox proportional hazard models. Propensity score was used to adjust for the nonrandomized assignment of local therapies.

RESULTS

A total of 75,539 nonmetastatic prostate cancer patients were identified who received either radiotherapy or no local treatment. Median age was 70 years. Median follow-up of alive subjects was 60 months, with an interquartile range of 47 to 77 months. Estimated 4-year overall survival of entire population was 88%. Significant prognostic variables for overall survival on multivariate analysis included age, grade, PSA level, T stage, and use of radiation therapy. Use of radiation therapy was the most powerful predictor of both cause-specific and overall survival (HR=0.41 and 0.46, respectively, P<0.001). The benefit conferred by local treatment was seen even in subjects with PSA≥75 ng/mL. Four-year cancer-specific survival was 93.8% in those receiving radiation treatments versus 76.5% in those who did not receive any local treatment.

CONCLUSIONS

Survival was significantly improved by radiotherapy for localized prostate cancer. Extremely high PSA levels (≥25 ng/mL) should not be considered a contraindication to local treatment.

Outcome of patients with localized prostate cancer treated by radiotherapy after confirming the absence of lymph node invasion

Objective

Management of lymph nodes in radiotherapy for prostate cancer is an issue for curative intent. To find the influence of lymph nodes, patients with T1–T3 prostate cancer and surgically confirmed negative nodes were treated with radiotherapy.

Methods

After lymphadenectomy, 118 patients received photon beam radiotherapy with 66 Gy to the prostate. No adjuvant treatment was performed until biochemical failure. After failure, hormone therapy was administered. Follow-up period was 57 months (mean).

Results

Biochemical failure occurred in 47 patients. Few failures were observed in patients with low (24%) and intermediate risks (14%). In contrast, 64% of high-risk patients experienced failure, 97% of whom showed until 36 months. Most patients with failure responded well to hormone therapy. After 15 months (mean), a second biochemical failure occurred in 21% of patients who had the first failure, most of them were high risk. Factors involving failure were high initial and nadir prostate-specific antigen, advanced stage, short prostate-specific antigen-doubling time and duration between radiation and first failure. Failure showed an insufficient reduction in prostate-specific antigen after radiotherapy. Factor for second failure was prostate-specific antigen-doubling time at first failure.

Conclusions

Half of high-risk patients experienced biochemical failure, indicating one of the causes involves factors other than lymph nodes. Low-, intermediate- and the other half of high-risk patients did not need to take immediate hormone therapy after radiotherapy. After failure, delayed hormone therapy was effective. Prostate-specific antigen parameters were predictive factors for further outcome.

Factors that predict treatment choice and satisfaction with the decision in men with localized prostate cancer

PURPOSE

Men diagnosed with localized prostate cancer (LPC) often have the opportunity to participate in the treatment choice. The purpose of this study was to evaluate relationships between influential factors on treatment choice and the decision-related outcomes of decisional conflict and satisfaction.

PATIENTS AND METHODS

This report presents data from 260 men diagnosed with LPC who were identified by their clinicians as having a choice of treatments. Men completed questionnaires at home within 2 weeks of the informational clinic visit with the clinician, but before treatment. The respondent sample had a mean age of 63.2 years (standard deviation, 8.1 years); the majority were married/partnered (82.7%), working (51.5%), white (93.8%), and educated at the collegiate level (83.8%). Personal factors (information, influential people, and outcomes), treatment choice, and decisional conflict and satisfaction with the decision (SWD) were queried. Relationships between all variables and the outcomes, SWD, and treatment choice were explored using exhaustive chi(2) automatic interaction detector.

RESULTS

The strongest predictor partition variable for SWD was the subscale "factors contributing to uncertainty" (adjusted P < 0.0001) followed by the Trait Anxiety score (adjusted P = 0.0388). The strongest predictive partition for the actual treatment choice was age group (adjusted P < 0.0001), followed by interacting marital status (adjusted P = 0.0003), influence of the urologist (adjusted P = 0.0008), and use of the Internet (adjusted P = 0.0479). Men with LPC were more satisfied with their treatment choice when they reported fewer uncertainty factors; these are factors mainly relevant to information needed to understand the pros and cons and to make a decision. Consistent with this finding for treatment choice is the use of the Internet, though this factor interacted with age, the influence of their surgeon, and marital status.

CONCLUSION

This study suggests that personally meaningful information communicated between patients and clinicians is paramount.

Is IMRT needed to spare the rectum when pelvic lymph nodes are part of the initial treatment volume for prostate cancer?

PURPOSE

To assess whether a 4-field box technique (4FBT), along with its technical refinements, is an adequate approach in terms of rectal sparing and target coverage for patients with localized prostate cancer undergoing whole-pelvic radiotherapy followed by a prostate boost and whether or not intensity-modulated radiotherapy (IMRT) is needed.

METHODS AND MATERIALS

For 8 patients, 31 plans were generated, each of them differing in one or more features, including prescription (dose/volume) and/or technical factors. For the latter, several "solutions" to try to reduce the amount of irradiated rectal volume were addressed, including modifications of the 4FBT and the use of sequential IMRT. We constructed a database with 248 plans that were tested for their ability to meet a series of rectal dose-volume constraints at V50, V60, V65, V70, V75, and V75.6. Multivariate logistic regression was used to identify factors independently associated with the end point. Successful solutions were also compared in terms of coverage of both pelvic node and prostate planning target volume (PTV) by isodose 95%.

RESULTS

At multivariate logistic regression, both rectal blocking and IMRT were independent predictors of the probability of meeting rectal dose-volume constraints during the pelvic and boost phases of treatment with close relative risks. However, on average, partial rectal blocking on lateral fields of 4FBT during whole-pelvic radiotherapy resulted in about 3% of pelvic node PTV being outside isodose 95%; only 2 of 8 patients had the pelvic nodal PTV covered similarly to what was achieved by whole-pelvis IMRT. Conversely, blocking the rectum during the last 3 fractions of the conformal boost showed a dosimetric coverage of prostate PTV similar to that achieved by IMRT boost. Interestingly, patient anatomic configuration was the strongest predictor of rectal sparing. Finally, the size of prostate margins to generate PTV was also independently associated with the probability of meeting rectal dose-volume constraints.

CONCLUSION

In the dose range of 70-76 Gy to the prostate, IMRT and standard techniques are equally effective in meeting rectal dose-volume constraints. However, whole-pelvis IMRT might be preferable to standard techniques for its slightly superior PTV coverage.