The Effect of Age on Prostate Implantation Results

Biochemical outcomes and toxicities in young men with prostate cancer after permanent iodine-125 seed implantation: Prospective cohort study in 6662 patients

PURPOSE

We evaluated the effect of age, <60 and ≥60 years, on biochemical outcomes and toxicities in patients with prostate cancer who underwent permanent seed implantation (PI) ± external beam radiation therapy ± hormone therapy in a national Japanese prospective cohort study (J-POPS).

METHODS AND MATERIALS

The safety and efficacy analyses included 6721 and 6662 patients, respectively. We categorized patients into two age groups: <60 (n = 716) and ≥60 (n = 6,005) years. We used propensity score matching (PSM) to estimate the marginal effect of age on biochemical freedom from failure (bFFF) using a Phoenix definition and Cox proportional hazard models.

RESULTS

The median followup period was 60.0 months. Without PSM, men <60 years demonstrated similar 5-year bFFF (96.3%) compared with men ≥60 years (95.6%; p = 0.576); percent positive biopsies, biologically effective dose, Gleason score, risk classification, and supplemental external beam radiation therapy (p <0.001, <0.001, <0.001, 0.008, and <0.001) were significantly associated with bFFF while age was not (p = 0.576). With PSM, bFFF was not significantly different between age groups (p = 0.664); however, men <60 years showed a significantly lower incidence of declining erectile function, grade ≥2 all urinary toxicities, urinary frequency/urgency, and rectal bleeding (p <0.001, 0.024, 0.031, and 0.010) than men ≥60 years.

CONCLUSIONS

After PI, men <60 years achieved a comparable 5-year biochemical control rate and showed a lower incidence of several toxicities compared to men ≥60 years. This suggests that PI should be an excellent treatment option for men <60 years with prostate cancer.

125I brachytherapy in younger prostate cancer patients : Outcomes in low- and intermediate-risk disease

PURPOSE

To evaluate local recurrence in younger men treated with low-dose-rate (LDR) ¹²⁵I brachytherapy (BT) for localized prostate cancer.

PATIENTS AND METHODS

A total of 192 patients (≤65-years-old) were treated with LDR ¹²⁵I-BT ± hormone therapy. Local failure was defined as any prostate-specific antigen (PSA) rise leading to salvage treatment or biochemical failure according to the Phoenix definition. A bounce was defined as a rise in the nadir of ≥0.2 ng/mL followed by spontaneous return. Proportions were compared using Fisher's exact tests; continuous variables using the unpaired t-test or its non-parametric equivalent. Cox proportional hazards models were applied for multivariable survival analysis.

RESULTS

Median follow-up was 66 months. The 5‑year local recurrence-free survival was 96.1%. Biopsy-proven local recurrence developed in 13 patients, 4 had a Phoenix-defined recurrence at the last follow-up. Androgen deprivation therapy was started in 1 patient without proven recurrence. Univariable risk factors for local recurrence were: at least 50% positive biopsies, intermediate risk, treatment with neoadjuvant hormone therapy, low preimplantation volume receiving 100% of the prescribed dose, and no bounce development. Hormone-naïve patients not attaining a PSA value <0.5 ng/mL during follow-up also had a higher risk of local recurrences. Cox regression demonstrated that the variables "at least 50% positive biopsies" and "bounce" significantly impacted local failure (hazard ratio, HR 1.02 and 11.59, respectively). A bounce developed in 70 patients (36%). Younger patients and those treated with a lower activity per volume had a higher chance of developing a bounce in the Cox model (HR 0.99 and 0.04, respectively).

CONCLUSION

For younger men, LDR BT is a valid primary curative treatment option in low-risk and is to consider in intermediate-risk localized prostate cancer.

Predictors in the outcome of 125I brachytherapy as monotherapy for prostate cancer

A number of different prostate cancer treatment modalities exist. Nomograms are used to assist clinicians and patients in choosing the most appropriate treatment. However, the predicted outcome for (125)I brachytherapy is much worse than what would be expected considering the actual survival rates. This underestimation may result in suboptimal treatment decisions. Therefore, better predictors for outcome after (125)I brachytherapy are necessary. The following factors, which may either influence outcome or predict outcome after brachytherapy, are discussed: tumor characteristics and risk stratification, patient age at treatment, obesity, adjuvant androgen-deprivation therapy, prostate-specific antigen bounce, implantation technique and dosimetry. For the prediction of outcome after (125)I brachytherapy, as long as the quality of the implant is optimal, only high-risk prostate cancer was found to have a negative impact on outcome.

The relationship between age at time of surgery and risk of biochemical failure after radical prostatectomy

OBJECTIVES

To evaluate the effects of age at radical prostatectomy (RP) on recurrence-free survival (RFS) in patients with prostate cancer stratified by established preoperative risk factors (such as prostate-specific antigen (PSA) level, Gleason score, and tumour stage), as increasing age has been associated with more indolent behaviour in some cancers.

PATIENTS AND METHODS

A retrospective analysis of men treated with RP from 1988 to 2008 was conducted. Patients were divided into two groups by age at the time of RP, and RFS rates were analysed using Kaplan-Meier survival curves. The subgroups were stratified by preoperative PSA level, biopsy Gleason score, and clinical stage; multivariate analyses with Cox proportional hazards models were used to identify independent predictors of recurrence. Recurrence was defined as a single PSA level of > or =0.2 ng/mL at least 28 days after RP.

RESULTS

In all, 1984 patients met inclusion criteria and were divided into groups 1 (1325 men aged 40-64 years) and 2 (659 men aged > or =65 years). The 5-year RFS rates were 80.6% (confidence interval, CI 78.0-82.9%) and 75.6% (CI 71.5-79.1%) for groups 1 and 2, respectively. In the univariate model, advanced age was significantly associated with an increased overall risk of recurrence (hazard ratio, HR 1.30, P = 0.012). However, in multivariate analyses accounting for PSA level, Gleason score, and clinical stage, age was not an independent predictor of recurrence (HR 1.04, P = 0.76).

CONCLUSION

Older patients who undergo RP appear to have an increased risk of recurrence. However, age is not an independent predictor of recurrence when accounting for PSA level, grade, and stage.

Surgery Versus Implant for Early Prostate Cancer: Results From a Single Institution, 1992–2005

PURPOSE

The aim of this study was to compare the biochemical disease-free survival rates for radical prostatectomy versus transperineal ultrasound-guided prostate implant for patients with early prostate cancer treated at a single institution from 1992 through 2005.

MATERIALS AND METHODS

The charts of 741 patients with early prostate cancer (350 implant and 391 surgery) treated from 1992 through 2005 were retrospectively reviewed. Surgery patients were treated by members of the academic Urology Section at Yale University School of Medicine. Implant patients were treated by a combined team from the Urology Section and the Department of Therapeutic Radiology at Yale Medical School. For the 350 implant patients, 35% were treated with iodine-125 and 65% with palladium-103. Of the implant patients 92% were treated with an implant alone and 8% with combined external beam radiation therapy plus an implant and 25% received short-term hormone therapy to downsize the prostate before the implant. Both surgery and implant patients were analyzed based on a group with favorable cancers (clinical stage T1c or T2, prostate-specific antigen <10, and Gleason score <7), an intermediate group (any 1 factor increased compared with the favorable group), and a poor group (any 2 factors increased compared with the favorable group). The follow-up time varied from 12 to 120 months with a mean/median follow-up time of 44 months/42 months for implant patients and 42 months/40 months for surgery patients. Prostate-specific antigen recurrence for surgery was defined as any detectable prostate-specific antigen after surgery. Prostate-specific antigen recurrence for implant was defined as the prostate-specific antigen nadir plus 2 ng/mL after implant. The biochemical disease-free survival rates were calculated using the life-table method.

RESULTS

The 5-year biochemical disease-free survival rates for radical prostatectomy versus implant were identical for the favorable group (93% versus 92%), intermediate group (70% versus 70%), and poor group (50% versus 52%) patients.

CONCLUSIONS

From 1992 through 2005, implant therapy produced equivalent 5-year biochemical disease-free survival rates compared with surgery in patients with early prostate cancer treated at a single institution.