Toxicity following high-dose salvage radiotherapy after radical prostatectomy

CyberKnife stereotactic radiotherapy for isolated recurrence in the prostatic bed

PURPOSE

To report a clinical experience of stereotactic body radiation therapy (SBRT) for isolated recurrence in the prostatic bed from prostate cancer.

MATERIALS AND METHODS

Between November 2011 and November 2013, 16 patients were treated with SBRT for a macroscopic isolated recurrence of prostate cancer in the prostatic bed. All patients were initially treated with radical prostatectomy, and half of them also received radiotherapy. Two schedules of SBRT were used: 30 Gy in 5 fractions in previously irradiated patients, 35 Gy in five fractions in radiotherapy-naïve patients.

RESULTS

At a median follow-up of 10 months (range 2-21 months), a significant biochemical response was found in all but one patient. At imaging evaluation, no local progression was noted: 10 patients showed partial response while four stable disease. At the moment of analysis, all 16 patients were alive. Seven of them experienced distant relapse, while nine maintained biochemical control, with no further therapy. Median time to relapse was 9.3 months (range 3-15.2 months). The treatment was well tolerated: One patient experienced G2 acute genitourinary and gastrointestinal toxicity.

CONCLUSIONS

Our experience shows that SBRT with CyberKnife for isolated nodal relapse is a safe and well-tolerated treatment.

Adjuvant and salvage radiotherapy after prostatectomy: outcome analysis of 307 patients with prostate cancer

AIM

In men with adverse pathology after radical prostatectomy, the most appropriate timing to administer radiotherapy (RT) remains a topic of debate. We analyzed in terms of efficacy, prognostic factors and toxicity the two therapeutic strategies: immediate postoperative radiotherapy (PORT) and salvage radiotherapy (SART).

MATERIALS AND METHODS

Between January 1995 and November 2010, 307 patients underwent adjuvant or salvage radiotherapy, after prostatectomy.

RESULTS

In the PORT group, 42 patients (20.7 %) had biochemical failure, with a median time to biochemical failure of 1.8 years; two parameters (age at diagnosis and PSA pre-RT) resulted to be significant at the survival analysis for overall survival (p = 0.003 and p = 0.046, respectively). In the SART group, 33 patients (31.7 %) had biochemical relapse; sixteen patients died of prostate cancer; postoperative hormones therapy, conformal radiotherapy and level of PSA pre-RT >1.0 ng/ml resulted to be significant at the survival analysis, p = 0.009, p = 0.039 and p = 0.002, respectively.

CONCLUSION

Our study is limited by its retrospective and nonrandomized design. As such, decisions to treat with adjuvant or salvage radiotherapy and the time to initiate therapy were based on patient preference and physician counseling. Our recommendation is to suggest adjuvant radiotherapy for all patients with adverse prognostic factors and to reserve salvage radiotherapy for low-risk patients, when the biochemical recurrence occurs.

Radiation therapy after radical prostatectomy: impact on metastasis and survival

PURPOSE

Although secondary radiation therapy decreases the risk of biochemical progression after radical prostatectomy, its impact on metastasis and survival is less well established. We evaluated the impact of adjuvant and salvage radiotherapy on clinical progression and mortality.

MATERIALS AND METHODS

A total of 361 patients who received adjuvant radiation were matched based on clinicopathological features to patients who did not receive adjuvant radiation in a 2:1 case-control ratio. Postoperative survival was estimated using the Kaplan-Meier method and compared using the log rank test. A second cohort of 2,657 men who experienced biochemical recurrence after prostatectomy was separately evaluated. Cox proportional hazard regression models were used to analyze the impact of salvage radiotherapy on disease progression and survival.

RESULTS

Adjuvant radiotherapy was associated with significantly improved 10-year biochemical recurrence-free survival (63% vs 45%, p <0.001), local recurrence-free survival (97% vs 82%, p <0.001) and a decreased need for late hormone therapy (17% vs 28%, p = 0.002) but did not impact systemic progression and overall survival (p = 0.94 and 0.27, respectively). Of the 2,657 patients who experienced biochemical recurrence after surgery 856 (32.3%) received salvage radiation. On multivariate analysis salvage radiotherapy decreased the risk of local recurrence (HR 0.13, 95% CI 0.06-0.28, p <0.0001) and delayed hormonal therapy (HR 0.81, 95% CI 0.71-0.93, p = 0.003) and systemic progression (HR 0.24, 95% CI 0.13-0.45, p <0.0001) but did not significantly impact mortality (p = 0.48).

CONCLUSIONS

Adjuvant and salvage radiation provide long-term local control and decrease the need for delayed hormonal therapy but neither improves survival. These results must be weighed against the potential morbidity of postoperative radiation when counseling patients.

A multi-institutional matched-control analysis of adjuvant and salvage postoperative radiation therapy for pT3-4N0 prostate cancer

OBJECTIVES

It is unclear whether postoperative salvage radiation therapy (SRT) and early adjuvant radiotherapy (ART) after radical prostatectomy lead to equivalent long-term tumor control. We studied a group of patients undergoing ART by comparing them with a matched control group undergoing SRT after biochemical failure.

METHODS

Using a multi-institutional database of 2299 patients, 449 patients with pT3-4N0 disease were eligible for inclusion, including 211 patients receiving ART and 238 patients receiving SRT. Patients were matched in a 1:1 ratio according to preoperative prostate-specific antigen Gleason score, seminal vesicle invasion, surgical margin status, and follow-up from date of surgery.

RESULTS

A total of 192 patients were matched (96:96). The median follow-up was 94 months from surgery and 73 months from RT completion. There was a significant reduction in biochemical failure with ART compared with SRT. The 5-year freedom from biochemical failure (FFBF) from surgery was 75% after ART, compared with 66% for SRT (hazard ratio [HR] = 1.6, P = .049). The 5-year FFBF from the end of RT was 73% after ART, compared with 50% after SRT (HR = 2.3, log rank [LR] P = .0007). From the end of RT, SRT and Gleason score >or=8 were independent predictors of diminished FFBF. From the date of surgery, Gleason score >or=8 was a significant predictor of FFBF.

CONCLUSIONS

Early ART for pT3-4N0 prostate cancer significantly reduces the risk of long-term biochemical progression after radical prostatectomy compared with SRT. Gleason score >or=8 was the only factor on multivariate analysis associated with metastasic progression.

Radiotherapy: long-term effects on gastrointestinal function

PURPOSE OF REVIEW

Radiotherapy frequently results in persistent effects on gastrointestinal function adversely impacting on the quality of life of patients cured of their malignant disease. Long-term effects on gastrointestinal function remain prevalent despite the advent of three-dimensional techniques of radiotherapy because higher radiation doses and more combined modality treatments are prescribed to improve cure rates.

RECENT FINDINGS

Chronic elevation of cytokine levels and implication of the cyclooxygenase-2 pathway in radiation bowel injury in animals, and the involvement of the Rho/Rho kinase pathway in the fibrogenic differentiation of smooth muscle cells of patients with late radiation enteritis, suggest a role for inhibition of these pathways. The importance of limiting acute gastrointestinal toxicity by dietary, pharmacological and physical interventions and of optimizing radiotherapy techniques and prescriptions is underscored by increasing evidence that a component of the long-term effects of radiotherapy on gastrointestinal function is a consequence of acute damage.

SUMMARY

Strategies to control acute toxicity are important in reducing the impact of long-term effects of radiotherapy on gastrointestinal function. Further research into genetic profiling to characterize individual risk of radiation bowel damage and the pathways implicated in fibrogenic differentiation is needed to reduce and prevent bowel complications.