Prostate-specific antigen to determine progression-free survival after radiation therapy for localized carcinoma of prostate

A retrospective analysis after low-dose-rate prostate brachytherapy with permanent 125I seed implant: clinical and dosimetric results in 70 patients

Aims and background

To evaluate the biochemical disease-free survival (bDFS) rate after 125I permanent-implant prostate brachytherapy.

Methods

Patients with a diagnosis of prostate adenocarcinoma and adequate PSA follow-up were selected for this retrospective study. Brachytherapy with permanent 125I seeds was performed as monotherapy, with a prescribed dose of 145 Gy to the prostate. Patients were stratified into recurrence risk groups according to the National Comprehensive Cancer Network (NCCN) guidelines. Biochemical failure was defined using the American Society of Therapeutic Radiology and Oncology (ASTRO) guidelines. The post-implant D90 (defined as the minimum dose covering 90% of the prostate) was obtained for each patient. Two cutoff points were used to test the correlation between D90 and bDFS results: 130 Gy and 140 Gy. bDFS was calculated from the implant date to the date of biochemical recurrence. Univariate and multivariate analysis were performed using the SPSS software and included clinical stage, pretreatment PSA, Gleason score (GS), androgen deprivation therapy, D90, and risk groups. In the univariate analysis we used a cutoff point of 5.89 ng/mL for PSA and 5 for GS.

Results

From June 2003 to April 2007, 70 patients were analyzed. The patients' distribution into recurrence risk groups was as follows: 39 patients (56%) in the low-risk group, 23 patients (33%) in the intermediate-risk group, and 8 patients (11%) in the high-risk group. At a median follow-up of 47 months (range, 19–70 months) bDFS was 88.4%, with a global actuarial 5-year bDFS of 86%. Disease-related factors including initial PSA level, GS and risk group were significant predictors of biochemical failure (P = 0.01, P = 0.01, P = 0.006, respectively). In multivariate analysis, risk group (P = 0.005) and GS (P = 0.03) were statistically significant.

Conclusion

Our data are in agreement with those in the literature and, despite the short follow-up, confirm the advantage of brachytherapy for patients at low and intermediate risk of recurrence.

Low-dose rate brachytherapy for men with localized prostate cancer

BACKGROUND

Localized prostate cancer is a slow growing tumor for many years for the majority of affected men. Low-dose rate brachytherapy (LDR-BT) is short-distance radiotherapy using low-energy radioactive sources. LDR-BT has been recommended for men with low risk localized prostate cancer.

OBJECTIVES

To assess the benefit and harm of LDR-BT compared to radical prostatectomy (RP), external beam radiotherapy (EBRT), and no primary therapy (NPT) in men with localized prostatic cancer.

SEARCH STRATEGY

The Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (from 1950), and EMBASE (from 1980) were searched in June 2010 as well as online trials registers and reference lists of reviews.

SELECTION CRITERIA

Randomized, controlled trials comparing LDR-BT versus RP, EBRT, and NPT in men with clinically localized prostate cancer.

DATA COLLECTION AND ANALYSIS

Data on study methods, participants, treatment regimens, observation period and outcomes were recorded by two reviewers independently.

MAIN RESULTS

We identified only one RCT (N = 200; mean follow up 68 months). This trial compared LDR-BT and RP. The risk of bias was deemed high. Primary outcomes (overall survival, cause-specific mortality, or metastatic-free survival) were not reported. Biochemical recurrence-free survival at 5 years follow up was not significantly different between LDR-BT (78/85 (91.8%)) and RP (81/89 (91.0%)); P = 0.875; relative risk 0.92 (95% CI: 0.35 to 2.42).For severe adverse events reported at 6 months follow up, results favored LDR-BT for urinary incontinence (LDR-BT 0/85 (0.0%) versus RP 16/89 (18.0%); P < 0.001; relative risk 0) and favored RP for urinary irritation (LDR-BT 68/85 (80.0%) versus RP 4/89 (4.5%); P < 0.001; relative risk 17.80, 95% CI 6.79 to 46.66). The occurrence of urinary stricture did not significantly differ between the treatment groups (LDR-BT 2/85 (2.4%) versus RP 6/89 (6.7%); P = 0.221; relative risk 0.35, 95% CI: 0.07 to 1.68). Long-term information was not available.We did not identify significant differences of mean scores between treatment groups for patient-reported outcomes function and bother as well as generic health-related quality of life.

AUTHORS' CONCLUSIONS

Low-dose rate brachytherapy did not reduce biochemical recurrence-free survival versus radical prostatectomy at 5 years. For short-term severe adverse events, low-dose rate brachytherapy was significantly more favorable for urinary incontinence, but radical prostatectomy was significantly more favorable for urinary irritation. Evidence is based on one RCT with high risk of bias.

Undetectable prostate specific antigen at 6-12 months

BACKGROUND

The concept of a prostate-specific antigen (PSA) "nadir" has been used as a predictive marker for treatment success in patients treated with radiotherapy for localized prostate carcinoma. However, this approach is not applicable in patients who are concomitantly treated with short-term hormonal therapies. To address this, the authors sought to develop a new predictive marker in such patients after prostate brachytherapy (BT).

METHODS

Between March 1997 and November 2002, 194 men with clinical Stage T1A-T3N0M0 prostate carcinoma (according to the 1992 International Union Against Cancer/American Joint Committee on Cancer TNM classification system) were treated with interstitial palladium (103Pd3) BT and androgen ablation therapy with or without external beam radiotherapy (EBRT). Based on tumor characteristics, 127 patients received an antiandrogen, finasteride, and BT whereas 67 received an antiandrogen, leuprolide, and EBRT followed by a BT boost. Hormonal therapy was initiated 2-3 months before any radiotherapy for a total duration of 8-9 months. Follow-up included physical examination and determining the PSA level at 3-month intervals. Postoperative serum testosterone was evaluated in preoperatively potent patients with erectile dysfunction > 6 months after therapy. A PSA level < or = 0.06 ng/mL or < or = 0.20 ng/mL detected during a 6-12-month window after the implant were evaluated as predictors of biochemically disease-free survival (DFS), defined as the time to a PSA level > or = 1.0 ng/mL.

RESULTS

Of the 194 patients, 163 were available for analysis. The median length of follow-up was 48 months. In those patients with a PSA level < or = 0.20 ng/mL at 6-12 months, the DFS at 48 months after the implant was 96% (95% confidence interval [95% CI], 91-99%) compared with the remainder of the patients, whose DFS decreased to 80% (95% CI, 65-89%) (P < 0.001). When a PSA level < or = 0.06 ng/mL was used as an indicator, the 48-month DFS was 99% (95% CI, 91-100%) compared with that for patients with a PSA level > 0.06 ng/mL, in whom the DFS was 85% (95% CI, 74-92%) (P = 0.004). Furthermore, because testosterone levels may occasionally remain low after the cessation of luteinizing hormone-releasing hormone agonist therapy and result in erectile dysfunction and an artificially low PSA level, the authors reviewed the serum testosterone levels in 23 patients who were so treated and were experiencing erectile dysfunction. None had PSA values below the lower limit of normal.

CONCLUSIONS

A PSA level < or = 0.20 ng/mL or < or = 0.06 ng/mL measured at 6-12 months after BT appears to be a useful predictive marker for detecting early success in patients with prostate carcinoma who are treated with neoadjuvant androgen ablation and BT. These markers may be used to identify those patients who are at an increased risk of biochemical failure and may be useful in stratifying patients for closer follow-up, long-term adjuvant therapies, or clinical trials. A longer follow-up period will be needed to verify whether these are predictive of long-term cancer control.

Biochemical outcomes after prostate brachytherapy with 5-year minimal follow-up: Importance of patient selection and implant quality

PURPOSE

A prostate brachytherapy program was initiated in 1990, when comparatively little was known of the relative importance of disease- and treatment-related factors on outcome. Patients treated during the first 6 years of the program were analyzed to determine the value of patient selection and implant quality on biochemical control.

METHODS AND MATERIALS

We treated 243 patients with clinically localized prostate cancer with radioactive seed implantation and underwent 1-month CT-based dosimetric analysis. Follow-up ranged from 61 to 135 months (median 75). The Gleason score was < or =6 in 78% (n = 189), 7 in 14% (n = 35), and 8-10 in 8% (n = 19). The initial prostate-specific antigen (PSA) level was < or =10 ng/mL in 61% (n = 149), 10.1-20 ng/mL in 26% (n = 63), and >20 ng/mL in 13% (n = 31). The disease stage was T2a or less in 49% (n = 120), and Stage T2b-T2c in 51% (n = 123). A real-time ultrasound-guided technique was used with (125)I (n = 138) and (103)Pd (n = 105) isotopes. No patient underwent external beam radiotherapy as part of their primary treatment. Of the 243 patients, 60% also received hormonal ablation for at least 3 months before and 2-3 months after seed implantation. All patients included underwent a 1-month CT-based dosimetric analysis. The implant dose was defined as the dose delivered to 90% of the prostate volume on postimplant dosimetry (D(90)). On the basis of prior dose-response analyses, patients were retrospectively grouped into optimal D(90) ((125)I > or =140 Gy Task Group 43 or (103)Pd >/=100 Gy) and suboptimal D(90) ( (125)I <140 Gy or (103)Pd <100 Gy) dose groups. Biochemical failure was defined using the American Society for Therapeutic Radiology Oncology definition.

RESULTS

Disease-related factors, including initial PSA level, Gleason score, and stage, were significant predictors of biochemical failure. The actuarial 8-year freedom from biochemical failure (bFFF) rate was 80% for those with a PSA level < or =10 ng/mL, 86% for PSA 10.1-20 ng/mL, and 45% for PSA >20 ng/mL (p = 0.0019). Patients with a Gleason score of < or =6 had an 8-year bFFF rate of 81% vs. 67% for those with Gleason score 7 and 53% for those with Gleason score 8-10 (p = 0.0003). Patients with Stage T2a or less had an 8-year bFFF rate of 85% compared with 69% for those with Stage T2b-T2c (p = 0.013). The 8-year bFFF rate was 88% for low-risk patients (Stage T2a or less, Gleason score < or =6, and initial PSA level < or =10 ng/mL; n = 75), 81% for moderate-risk patients (Stage T2b or Gleason score 7 or initial PSA level >10.1-20 ng/mL; n = 70), and 65% for high-risk patients (two or more moderate-risk features or Gleason score > or =8 or initial PSA level >20 ng/mL; n = 98; p = 0.0009). Patients with optimal dose implants (n = 145) had an 8-year bFFF rate of 82% compared with 68% for those with suboptimal dose implants (n = 98; p = 0.007). Hormonal therapy did not significantly affect biochemical failure (p = 0.27). In multivariate analysis, the statistically significant variables included initial PSA level (p <0.0001), Gleason score (p = 0.024), and dose group (p = 0.046). Because our current practice limits implantation alone to low-risk patients, an analysis of this subgroup was undertaken to validate the importance of dose. In the optimal dose group, low-risk patients had an 8-year bFFF rate of 94% vs. 75% for the low-risk patients in the suboptimal dose group (p = 0.02).

CONCLUSION

With minimal follow-up of 5 years, these data continue to support the use of implantation alone in low-risk prostate cancer patients and demonstrate the importance of implant quality (dose) in achieving optimal outcomes. Low-risk patients who receive an optimal dose implant have a 94% bFFF rate at 8 years.

Molecular Markers in Prostate Cancer: The Role in Preoperative Staging

Radical prostatectomy as a primary treatment for clinically localized prostate cancer has increased dramatically over the past decade due to prostate-specific antigen (PSA) screening and the awareness of the increased incidence of localized disease. Despite the stage migration to increase clinically localized disease, there are still vast numbers of men who harbor occult extraprostatic extension and develop recurrence after surgery. The study of molecular markers in the blood or tissue of surgical patients prior to treatment, called " molecular staging, " is the focus of this review. The reverse transcriptase- polymerase chain reaction (RT-PCR) test for PSA gene expression in peripheral blood or bone marrow has received considerable attention since its first report in 1992. The test detects messenger RNA species for prostate-specific/abundant genes such as PSA and prostate-specific membrane antigen. These messenger RNAs were not detected in normal blood or bone marrow, but were detected in some prostate cancer patients presumably due to circulating prostatic epithelial cells. These prostate epithelial cells are thought to be occult metastases cells, and early studies correlated a positive RT-PCR test with surgical pathology adverse features such as positive margins. Despite the many studies over the past few years, there have been inconsistent results, and the most recent studies have not been able to confirm clinical utility. Bone marrow RT-PCR has been more promising; however, it is still a research tool that needs further study. The study of molecular markers in tissue material, ie, prostate biopsy samples prior to radical prostatectomy, is problematic due to the sampling error inherent in a multifocal heterogeneous tumor such as prostate cancer. The tumor suppressor proteins p53 and p27, Bcl-2 oncoprotein, Ki-67 proliferation index protein, E-cadherin, and microvessel density have been assessed in preradical prostatectomy needle biopsy. Results have been conflicting, and none are yet accepted as a clinically useful marker. Current and future work is focusing on analysis of multiple gene expressions or proteins simultaneously via gene chip or proteomics technology. While these expression profiles might be of value in whole prostate surgical specimens where tissues are well characterized, it is unclear how this new technology will be applied to the needle biopsy samples. Although molecular staging of radical prostatectomy patients has been under study for a decade, all assays remain research tools. Still, this area holds great promise for improving the accuracy of staging and providing a more accurate prognosis of individual men with clinically localized prostate cancer.

[Results of external radiotherapy in localized cancer of the prostate]

OBJECTIVE

External radiotherapy is considered to be a modality of treatment with a curative purpose for carcinoma de prostata. We have analysed a series of patients that received radical irradiation as treatment for tumor prostatic. We have the biochemical control results for these patients. We introduce the connection of the PSA nadir value (nPSA) and other prognostic variables with the survival free of biochemical failure.

MATERIAL AND METHODS

Between January 1992 to January 1998, 46 patients with prostate cancer T1-3 NX M0 received external radiotherapy with a curative purpose. A number of 26 of these patients received treatment with androgen blockers. The answer to this treatment was established as a fall in PSA to levels equal/minor than 1.5 ng/ml. The biochemical relapse was established as three rises of PSA over the value of nPSA.

RESULTS

We introduce the connection between nPSA and prognostic variables (clinic stage, gleason, PSA pretreatment y hormonal therapy). Three of these variables--clinic stage, Gleason grade and hormonal therapy--were the ones that showed a significantly connection with obtaining a low level of PSA. The 3-year actuarial BDFS was of 69.5%. The BDFS was of 84.3%, 9% and 6% for a value of nPSA of < or = 1 ng/ml, 1-2 ng/ml and > 2 ng/ml respectively (p < 0.05).

CONCLUSION

Radiotherapy seems to be a good therapeutical option with patients suffering from localised prostate carcinoma. The nPSA value after radiation is a good early determinant of outcome.

The role of imaging studies and molecular markers for selecting candidates for radical prostatectomy

For the typical patient who has newly diagnosed prostate cancer, clinically organ-confined disease of moderate grade, and a PSA less than 10 ng/mL, the current role of imaging studies and molecular biomarkers is limited. Bone scans are not necessary for newly diagnosed men with a PSA less than 10 ng/mL in the absence of bone pain. Similarly, abdominal and pelvic CT scanning rarely provides any useful diagnostic or staging information when the PSA is less the 20 ng/mL and is indicated rarely. Endorectal coil MR imaging adds staging information for patients with a PSA between 10 and 20 ng/mL, a Gleason score of 7 or less, and 50% or more positive biopsies on a sextant sampling. Indium 111 capromab pendetide scanning (ProstaScint) is FDA-approved to evaluate newly diagnosed patients at high risk for metastases. These patients have a Gleason score of 7 or greater and a PSA greater than 20 ng/mL, a Gleason score of 8 to 10 regardless of the PSA value, or clinical stage T3 disease and a Gleason score of 6 or greater. RT-PCR testing of blood or bone marrow for prostate-specific or prostate cancer-specific gene expression, or "molecular staging," is a promising technique whose current use is still investigational. Much useful information may be gained by careful study of prostate needle biopsy material. Aside from current Gleason grading and the number or percentage of cores involved with cancer, no molecular biomarker is approved for clinical use. p27, p53, bcl-2, Ki-67 (MIB-1), and the assessment of neovascularity hold promise, but prospective multicenter studies are needed. In the long-term, multiple gene expression profiling of biopsy material using gene chips may revolutionize the care of patients with prostate cancer and those who elect radical prostatectomy.

A retrospective analysis of the results of p(65) + Be neutrontherapy for the treatment of prostate adenocarcinoma at the cyclotron of Louvain-la-Neuve. Part I: Survival and progression-free survival

PURPOSE

To retrospectively evaluate survival, progression-free survival (PFS) and biological response in a series of patients irradiated with mixed neutron/photon beams for locally advanced prostate cancer in our institution.

PATIENTS AND METHODS

Three hundred and eight patients were treated between January 1990 and December 1996. Fifty-five of these were recruited for pT3 or pN1 tumors after radical prostatectomy. Neoadjuvant androgen deprivation was given in 106 patients. The treatment protocol consisted of a mixed photon/neutron irradiation in a two-to-three proportion, up to a total equivalent dose of 66 Gy (assuming a clinical RBE value of 2.8). Pre- and post-treatment PSA determinations were available in practically all cases. Study endpoints were overall survival (OAS) and progression-free survival (PFS). The Cox proportional hazard regression model was used to investigate the prognostic value of baseline characteristics on survival and progression-free survival were a progression was defined as local, regional, metastatic or biological progression. Mean age was 69 years (49-86); mean pretreatment PSA was 15 (0.5-330) in all patients and 14 (0.5-160) in those receiving neoadjuvant hormonotherapy; seven patients only had an initial PSA < or = 4 ng/mL; 15% were T1, 46% were T2, 28% were T3 or pT3 and 4% were T4 (7% unspecified); WHO grade of differentiation was I in 38%, II in 38% and III in 14% (5% unspecified).

RESULTS

The median follow-up was 2.8 years (0-7.8). Five-year overall survival (OAS) was 79% (95% CI: 71-87%) and 5-year progression-free survival (PFS) was 64% (95% CI: 54-74%) for the entire series. PFS in patients with an initial PSA > or = 20 ng/mL was the same. PFS could be predicted by two optimal Cox regression models, one including histological grade (p = 0.003) and initial PSA (p = 0.0009) as cofactors, the other including histological grade (p = 0.003) and T stage (p = 0.02). The main prognostic factors for overall survival were PSA and age. Biological responses with PSA < 1.5 ng/mL, < 1 ng/mL and < 0.5 ng/mL at any time after treatment were documented in 70%, 61% and 47% of the patients, respectively.

CONCLUSION

Five-year OAS was 79%, PFS was 64%, and biological response was 70% for prostate cancer patients treated with mixed photon/neutron beams as applied at Louvain-la-Neuve, which are good results as compared with the literature. The usual prognostic factors were confirmed.

Fifteen-year minimum follow-up of a prostate brachytherapy series: comparing the past with the present

OBJECTIVES

To report the overall survival for 126 patients more than 15 years after iodine-125 interstitial therapy; to report the biochemical progression status for those alive and clinically without evidence of disease for longer than 15 years; to document the upward migration of grade by date of grade assignment; to compare the tumor stage and grade profile of this mature series with our current experience; and to clarify the prostate-specific antigen (PSA) data when this series is used as a historical comparison.

METHODS

The records of 126 patients who underwent interstitial therapy more than 15 years previously were reviewed for assessment of the current TNM stage and Gleason grade and the current PSA level for patients clinically free of disease. The tumor grade and stage of these patients were compared with those of the first 126 patients treated by transrectal ultrasound-guided brachymonotherapy at our center between January 1995 and January 1999. The methodology of our 1993 publication was also reviewed.

RESULTS

Of the 16 patients clinically free of disease (13 still alive and 3 dead of other causes more than 15 years after therapy), a review of the initial diagnostic needle biopsy was unable to confirm the presence of tumor in 3 patients. Of the remaining 13, 4 had a PSA level of 0.2 ng/mL or less, 4 a PSA level between 0.21 and 0.9 ng/mL, and 5 a PSA level between 1 and 2.5 ng/mL. Re-evaluation of the histopathologic findings using current criteria increased the Gleason score and World Health Organization grade. Patients currently selected for brachytherapy have a lower Gleason grade and TNM stage than recorded for patients treated in the past. The actuarial progression probability curves using the 0.5 or less cutpoint published in 1993 represented the best possible outcome and cannot serve as a historical control for current series comparisons.

CONCLUSIONS

For patients who were alive and clinically free of disease longer than 15 years after therapy, the biochemical PSA levels were low. This may be attributed to the therapeutic radiation effect. Whether the improved technology of current transrectal ultrasound-guided implants can extend these favorable results from a small minority to a significant majority and whether it can approach the therapeutic results of radical prostatectomy may be partially answered with a longer follow-up of the current series. The histopathologic criteria have been refined, and upgrading from the initially assigned grade is common. In some cases, a prostate cancer diagnosis could not be confirmed. These findings limit the ability to match patients across time and institution. The results of our 1993 report of biochemical chemical progression-free probability 10 years after iodine-125 implantation cannot be used as a comparator for current studies. Ultimately, a valid comparison between treatment options will only be achieved through a randomized controlled trial.

Simultaneous irradiation for prostate cancer: intermediate results with modern techniques

PURPOSE

In this study of men with early stage prostate cancer we evaluated treatment outcome after modern simultaneous irradiation, comprising transperineal implantation followed by external beam radiation. Disease-free survival rates were calculated according to an undetectable prostate specific antigen (PSA) nadir.

MATERIALS AND METHODS

From 1992 to 1996, 689 men with clinical stage T1-T2, N0, Nx prostate cancer were treated with ultrasound guided transperineal 125iodine seed implantation followed 3 weeks later by external beam radiation. Disease-free status was defined as the achievement and maintenance of a PSA nadir of 0.2 ng./ml. or less. Median followup was 4 years (range 3 to 7). None of these men received neoadjuvant or adjuvant hormonal therapy.

RESULTS

Overall 5-year disease-free survival was 88%. The 5-year rate according to PSA 4.0 ng./ml. or less, 4.1 to 10.0, 10.1 to 20.0 and greater than 20.0 was 94%, 93%, 75% and 69%, respectively. Multivariate analysis revealed that pretreatment PSA was the strongest indicator of subsequent disease-free status in regard to Gleason score or clinical stage.

CONCLUSIONS

Intermediate treatment outcome analysis of modern simultaneous radiation supports the principles of radiation dose intensification for intracapsular disease plus the treatment of potential microscopic capsular penetration.

Salvage radical prostatectomy after radiation therapy and brachytherapy

Local recurrence after any type of radiation therapy presents the clinician with a significant challenge. If there is no evidence of metastatic disease, patients can be offered a potentially curative salvage prostatectomy. To qualify for such surgery, patients should be at least 12 months from the completion of radiation and have at least a 10-year life expectancy; ideally, they will have a serum prostate specific antigen concentration <10 ng/mL and a Gleason score of 7 or less. Perioperative complications are substantial, with urinary incontinence rates of 40% to 50% and rectal injury rates of 10% to 15%. Long-term disease-free survival rates of 30% to 40% can be expected.

The durability of external beam radiation therapy for prostate cancer: can it be identified?

PURPOSE

We establish criteria to identify a durable response to external beam radiation therapy by calculation of biochemical progression-free probability for patients who attained and maintained defined nadir prostate specific antigen (PSA) levels more than 5 years after treatment.

MATERIALS AND METHODS

A total of 460 patients were treated with external beam radiation monotherapy from 1976 to 1995. Patients with PSA less than 0.5 (group 1) or 0.5 to 1.0 (group 2) ng./ml. more than 5 years after treatment were identified. Treatment failure was defined as 3 consecutive increases in PSA after nadir. Progression-free probability after 60 months was calculated for each group. A comparison was also made to patients achieving the same nadir levels anytime after treatment.

RESULTS

Failure occurred at 133 months in 1 of 26 group 1 patients (4%) and at a median of 76 months in 5 of 26 group 2 patients (19%). At 10 years progression-free probability was 91% for group 1 compared to 72% for group 2 (p = 0.0575). These same nadir levels anytime after treatment were associated with higher failure rates of 55% for group 1 and 72% for group 2.

CONCLUSIONS

If a PSA nadir of less than 0.5 ng./ml. was maintained 5 years after therapy, subsequent failure was rare. Although statistical significance was not reached (p = 0.0575), a higher failure rate was noted if the nadir PSA was 0.5 to 1.0 ng./ml. at 5 years. Thus, patients with PSA 0.5 to 1.0 ng./ml. require careful continued surveillance. Nadir levels less than 1.0 ng./ml. anytime before 5 years were associated with a substantial risk of subsequent progression.

Conventional external-beam radiation therapy alone or with androgen ablation for clinical stage III (T3, NX/N0, M0) adenocarcinoma of the prostate

PURPOSE

To evaluate the outcome of clinical Stage III (T3, N0/NX, M0) prostate cancer treated by conventional radiation alone or with adjuvant androgen ablation.

METHODS AND MATERIALS

Three hundred forty-four men with T3, N0/NX, M0 adenocarcinoma of the prostate who received conventional radiation alone (260) or with androgen ablation (84) were analyzed for relapse or rising prostate-specific antigen (PSA), using univariate and multivariate techniques.

RESULTS

With a median follow-up of 68 months, the 260 men treated with radiation alone had a 10-year actuarial rate of relapse or rising PSA of 76%. Pretreatment PSA level (< or = 10 ng/ml vs. > 10 < or = 20 ng/ml vs. > 20 ng/ml) and radiation dose (< 68 Gy vs. > or = 68 Gy) were the only independently significant determinants of biochemical failure; Gleason score (2-7 vs. 8-10) was an additional determinant of metastatic relapse. Patients treated to doses < 68 Gy experienced 6-year failure rates exceeding 50% regardless of PSA level. Patients with PSA < or = 10 ng/ml and receiving 68-70 Gy had a 6-year failure of 24%, but those with PSA > 10 ng/ml had relapse rates exceeding 50% even at doses of 70 Gy. At a median follow-up of 44 months, the 84 patients treated with radiation and androgen ablation had a 6-year biochemical failure rate of 22%. The only significant determinant of outcome in this group was pretreatment PSA; patients with PSA < or = 80 ng/ml had a 6-year failure rate of only 12% compared to a failure rate of 53% for those with PSA > 80 ng/ml. The outcome for those treated with combined modalities was significantly better than for those treated with radiation alone in all PSA strata.

CONCLUSION

Conventional radiation alone has little curative potential for Stage III disease. Doses < 68 Gy are particularly ineffective. Patients with PSA < or = 10 ng/ml may be candidates for conventional radiation to a dose of 70 Gy. Other patients are probably best served by combined radiation-androgen ablation or high-dose conformal radiation.

BCL-2 and p53 expression in clinically localized prostate cancer predicts response to external beam radiotherapy

PURPOSE

Clinicians have long been hampered by the inability to distinguish patients with localized prostate cancer who will and will not respond to radiotherapy. In a significant proportion of patients therapy fails as determined by increasing posttreatment serum prostate specific antigen (PSA). We evaluated the expression of 2 key regulators of apoptosis, bcl-2 and p53, relative to treatment outcomes in patients who received external beam radiotherapy for clinically organ confined carcinoma of the prostate.

MATERIALS AND METHODS

Immunohistochemical staining for bcl-2 and p53 on pretreatment needle biopsies was performed in 54 patients who were treated with radiotherapy for localized prostate cancer. Expression was scored using strict criteria. Nadir PSA less than 1 ng./ml. after therapy was considered a successful treatment response.

RESULTS

There was a predominance of stage T1c cancer (74%) with a mean Gleason score of 6.9 and an average pretreatment PSA of 25.3 ng./ml. Overall 54% of the patients did not have a nadir PSA of less than 1 ng./ml. Of the bcl-2 positive cases therapy ultimately failed in 85%. Similarly 88% of the patients with p53 positive biopsies had treatment failure and in all with bcl-2 as well as p53 expression radiotherapy failed. Expression of bcl-2 and p53 was an independent prognostic variable for treatment failure with odds ratios (95% confidence interval) of 7.3 and 10.8, respectively.

CONCLUSIONS

Expression of bcl-2 and p53 was associated with treatment failure after external beam radiation therapy. These findings suggest that bcl-2 and p53 expression in pretreatment biopsies may be helpful for predicting response to definitive radiotherapy.

Salvage brachytherapy for localized prostate cancer after radiotherapy failure

OBJECTIVES

To evaluate the effectiveness and morbidity of salvage brachytherapy for locally recurrent or persistent prostate cancer after radiotherapy failure.

METHODS

In this retrospective study, 49 patients of median age 73.3 years (range 52.9 to 86.9) with biopsy-proven localized prostate cancer underwent interactive transperineal fluoroscopic-guided and biplane ultrasound-guided brachytherapy with either iodine 125 or palladium 103 after prior radiotherapy failure. Post-treatment follow-up was conducted for a median of 64.1 months (range 26.6 to 96.8) and included clinical assessment of disease status, assays of serum prostate-specific antigen (PSA) levels, and documentation of treatment-related symptoms and complications. Determination of biochemical treatment failure was based on two successive rising PSA values above the post-treatment PSA nadir value.

RESULTS

The actuarial rate of local prostate cancer control was 98% (95% confidence interval [CI] 94% to 99%). Actuarial disease-specific survival at 3 and 5 years was 89% (95% CI 73% to 96%) and 79% (95% CI 58% to 91%), respectively. At 3 and 5 years, actuarial biochemical disease-free survival was 48% (95% CI 32% to 63%) and 34% (95% CI 17% to 51%), respectively. Post-treatment PSA nadir was found to be a significant predictor of biochemical disease-free survival. Actuarial biochemical disease-free survival of patients who achieved a PSA nadir less than 0.5 ng/mL was 77% (95% CI 53% to 90%) and 56% (95% CI 25% to 78%) at 3 and 5 years, respectively. Of 49 patients, 23 (47%) achieved a post-treatment PSA nadir less than 0.5 ng/mL. The incidence of serious complications after salvage brachytherapy, such as incontinence and rectal complications, was lower than that reported after other types of salvage procedures.

CONCLUSIONS

Interactive transperineal fluoroscopic-guided and biplane ultrasound-guided brachytherapy is a novel, potentially curative salvage modality for patients in whom prior radiotherapy failed. In a population of patients with poor prognosis, this modality was associated with a high rate of local prostate cancer control and a 34% actuarial rate of biochemical disease-free survival at 5 years. The incidence of major complications after salvage brachytherapy appears to be lower than that after other potentially curative salvage procedures, such as radical prostatectomy and cryoablation. Salvage brachytherapy warrants further investigation.

Biochemical response to testicular androgen ablation among patients with prostate cancer for whom flutamide and/or finasteride therapy failed

OBJECTIVES

To evaluate the response of testicular androgen ablation in patients with advanced prostate cancer with a biochemical recurrence after finasteride or combined finasteride and flutamide therapy.

METHODS

Eighteen hormone naïve men with advanced prostate cancer (10 with detectable prostate-specific antigen [PSA] levels after radical prostatectomy, 4 with rising PSA levels after definitive radiation therapy, and 4 with Stage D2 disease) were treated with finasteride (5 mg/day) alone or in combination with flutamide (250 mg three times a day). All men experienced an initial reduction in serum PSA, but later had treatment failure with two consecutive rising PSA measurements. All men were then treated with testicular androgen ablation (bilateral orchiectomy in 15 and luteinizing hormone-releasing hormone analogue in 3).

RESULTS

Overall, serum PSA declined by more than 80% in 15 (83%) of 18 and to undetectable levels in 14 (78%) of 18. With a median+/-semi-interquartile range follow-up of 22+/-14.5 months from the initiation of hormone therapy, 12 (67%) of 18 currently have undetectable PSA levels. Two men having rising serum PSA levels above 100 ng/mL and 1 man has died from complications of metastatic prostate cancer.

CONCLUSIONS

Testicular androgen ablation effectively lowers serum PSA levels in most men with advanced prostate cancer who have experienced a biochemical recurrence despite initial response and subsequent relapse on finasteride or combined finasteride and flutamide therapy.

Evaluation and management of the man who has failed primary curative therapy for prostate cancer

The recurrence of prostate cancer after potentially curative local therapy is becoming a significant urologic problem. There are few prospective randomized trials, and the optimal diagnostic and treatment strategies for men who fail potentially curative therapy are not known. The experience to date seems to suggest the following as a reasonable approach. A detectable serum PSA level (> or = 0.4 ng/mL) after radical prostatectomy is evidence of residual or recurrent prostate cancer. Men with low- or moderate-grade cancers (Gleason score < 7), with capsular penetration, or with positive surgical margins in whom disease recurs more than 2 years after radical prostatectomy with a PSA doubling time greater than 12 months seem likely to harbor a local recurrence and are the only good candidates for salvage therapy. Unless there is a palpable recurrence, transrectal ultrasound and biopsy are generally not recommended, and CT scanning and bone scintigraphy usually do not provide helpful information. The role of monoclonal antibody scanning is currently investigational. Men with high-grade tumors (Gleason score > or = 7) or with seminal vesicle or lymph node involvement in whom disease recurs within 2 years of radical prostatectomy are most appropriately observed or treated with early hormonal therapy. Men who do not achieve a PSA nadir of 0.5 ng/mL or less within 2 years of radiotherapy are very likely to harbor residual disease. For young healthy men who are willing to accept a substantial risk of impotency, urinary incontinence, and bladder neck contractures, salvage radical prostatectomy is a reasonable option if the preradiation tumor characteristics are acceptable (PSA < 10 ng/mL, Gleason score < or = 6) and if the current PSA is less than 10 ng/mL. Salvage cryotherapy may result in substantial morbidity and should only be offered on an investigational basis. Other men failing radiation may be observed or treated with hormonal therapy. There is seldom a role for repeat biopsy. Because the optimal time to begin hormone therapy is still not known, early or delayed treatment are both reasonable options. Testicular androgen ablation by orchiectomy or LHRH agonists is considered standard therapy. Combined therapy with an antiandrogen does not seem to be beneficial for all patients and should not be routinely used. Sexually active men in whom preservation of potency is important can be offered an investigational regimen such as a 5-alpha-reductase inhibitor combined with an oral antiandrogen or intermittent LHRH agonist therapy. It is hoped that the results of ongoing randomized trials and future research will establish efficient and effective practice guidelines to evaluate and treat men who have failed potentially curative therapy for localized prostate cancer. This remains a very important and controversial topic that will challenge many practicing urologists.

A new look at an old option in the treatment of early-stage prostate cancer: hormone therapy as an alternative to watchful waiting

Watchful waiting is an attractive option in the management of early-stage, low-grade prostate cancer because of the high financial costs and complication risks associated with surgery and radiotherapy. Despite the drawbacks of current local therapy, neither treatment can demonstrate a discernible survival benefit over observation alone. Even the slowest progressing disease, however, can potentially develop into a deadly medical problem. As a result, physicians and patients frequently have difficulty accepting untreated cancer. Therefore, we propose that another option be considered in cases of prostate cancer that would otherwise qualify for observation alone: the use of two oral hormonal agents, flutamide and finasteride, to achieve complete androgen blockade. Some evidence exists which suggests that such therapy may improve symptom-free survival, and perhaps overall survival as well. This 'aggressive' form of 'conservative' therapy may satisfy patient concerns that are not adequately addressed by current forms of therapy.

Actuarial disease-free survival after prostate cancer brachytherapy using interactive techniques with biplane ultrasound and fluoroscopic guidance

PURPOSE

To evaluate the effectiveness and safety of interactive transperineal brachytherapy under biplane ultrasound and fluoroscopic guidance in patients with localized prostate cancer.

METHODS AND MATERIALS

Brachytherapy using 125I or 103Pd radioactive seeds either alone or in combination with adjunctive external beam radiotherapy (XRT) was administered to 490 patients at a single institution. Post-treatment follow-up included clinical assessment of disease status, assays of serum prostate-specific antigen (PSA) levels and documentation of treatment-related symptoms and complications.

RESULTS

Actuarial disease-free survival at 5 yr was 79% (95% CI, 71-85%), and the 5-yr actuarial rate of local control was 98% (95% CI, 94-99%). Post-treatment PSA nadir and pretreatment PSA level were found to be significant predictors of disease-free survival. In patients with a PSA nadir < 0.5 ng/ml, 5-yr disease-free survival was 93% (95% CI, 84-97%), compared with 25% (95% CI, 5-53%) in patients whose PSA nadir was 0.5-1.0 ng/ml and 15% (95% CI, 3-38) in patients with a PSA nadir > 1.0 ng/ml. Brachytherapy was well tolerated with few post-treatment complications.

CONCLUSION

A broad range of patients with localized prostate cancer can benefit from transperineal brachytherapy with minimal morbidity. A post-treatment PSA nadir below 0.5 ng/ml provides a useful prognostic indicator of favorable long-term outcome.

Ten-year disease free survival after transperineal sonography-guided iodine-125 brachytherapy with or without 45-gray external beam irradiation in the treatment of patients with clinically localized, low to high Gleason grade prostate carcinoma

BACKGROUND

The authors report observed 10-year brachytherapy results in the treatment of 152 consecutive patients with clinically organ-confined prostate carcinoma.

METHODS

One hundred and fifty-two consecutive patients with T1-T3, low to high Gleason grade, prostate carcinoma were treated between January 1987 and June 1988 at Northwest Hospital in Seattle, Washington. Their median age was 70 years (range, 53-92 years). Of these 152 patients, 98 (64%) received an iodine-125 implant alone (Group 1), and the remaining 54 patients (36%), who were judged to have a higher risk of extraprostatic extension, also were treated with 45 gray (Gy) of external beam irradiation to the pelvis (Group 2). No patient underwent lymph node sampling, and none received androgen ablation therapy. Multivariate regression and the Mann-Whitney rank sum test were used for statistical analysis. Preoperative patient data with associated success or failure outcomes at 10 years after treatment were used for training and validating a back-propagation neural network prediction program.

RESULTS

The average preoperative prostate specific antigen (PSA) value, clinical stage, and Gleason grade were 11.0 ng/mL, T2, and 5, respectively. The median posttreatment follow-up was 119 months (range, 3-134 months). Overall survival 10 years after treatment was 65%. At last follow-up only 3 of the 152 patients (2%) had died of prostate carcinoma. Ninety-seven patients (64%) remained clinically and biochemically free of disease at 10 years of follow-up and had an average PSA value of 0.18 ng/mL (range, 0.01-0.5 ng/mL). In these patients a period of 42 months was required to reach the average PSA (0.5 ng/mL). The median to last PSA follow-up was 95 months (range, 3-134 months). Postoperative needle biopsies were negative in 56% of patients, positive in 15% of patients, and not available in 29% of patients. Only 6% of patients developed bone metastasis. At 10 years there was no statistically significant difference in treatment outcome between patients who received iodine-125 alone, and those who received iodine-125 with 45-Gy external beam irradiation (P = 0.08). Nevertheless, in these two groups preoperative PSA, stage, and Gleason grade were significantly different (P < 0.01). In the artificial neural network analysis, pretreatment serum PSA was the most accurate predictor of disease-free survival.

CONCLUSIONS

Percutaneous prostate brachytherapy is a valid and efficient option for treating patients with clinically organ-confined, low to high Gleason grade, prostate carcinoma. Observed 10-year follow-up documents serum PSA levels superior to those reported in several published external beam irradiation series, and comparable to those published in a number of published radical prostatectomy series.

The relationship between biochemical failure and time to nadir in patients treated with external beam therapy for T1-T3 prostate carcinoma

PURPOSE AND BACKGROUND

To determine a prostatic-specific antigen (PSA) nadir value and time to nadir that predict a high probability of freedom from biochemical failure in men treated with external beam therapy for prostate cancer.

MATERIALS AND METHODS

Between January 1990 and March 1994, 228 men with T1-T3 adenocarcinoma of the prostate received a radical course of external beam irradiation with no prior or adjuvant hormonal therapy. All men had pre- and post-treatment serum PSA evaluations, and were followed up for at least 24 months, to ensure PSA nadir was reached. Biochemical failure was defined as three successive post-treatment rises in serum PSA, regardless of the magnitude of elevation.

RESULTS

Overall, 4-year biochemical disease-free survival (BDFS) was 42%. PSA nadir was predictive of subsequent BDFS. For those whose serum PSA nadir was < or =1 ng/ml, 4-year BDFS was 70%, versus 12% for those with serum PSA nadir > 1 ng/ml (P = < 0.001). The 4-year BDFS for patients with time to nadir < or =1 year, was 28%, versus 58% for those with time to nadir > 1 year (P < 0.001). For patients with PSA nadir < or =1 ng/ml, 4-year BDFS was 75% for those with time to nadir > 1 year, versus 61% for those with time to nadir < or =1 year (P < 0.021). In multivariate analysis, PSA nadir(< or =1 ng/ml versus >1 ng/ml, and time to nadir (< or =1 year versus > year) were independent predictors of BDFS alone with pre-treatment PSA and Gleason score.

CONCLUSION

Only those who achieved PSA nadir < or =1 ng/ml following external beam therapy have a favourable chance of lasting biochemical disease control, while those with nadir > 1 ng/ml have a high subsequent failure rate. The prognosis is better in patients with late time to nadir. In addition to PSA nadir, time to nadir, pretreatment PSA, and Gleason score were of independent prognostic significance.

Is prostate specific antigen density an important prognostic indicator for patients with prostate cancer treated with external beam therapy?

The purpose of this study was to determine if prostate specific antigen density (PSAD) is a predictor of outcome following external beam radiotherapy for prostate cancer, and to compare it with other prognostic factors. Between January 1990 and December 1993, 205 patients with T1-T3 adenocarcinoma of the prostate received a radical course of external beam irradiation, with no prior or adjuvant hormonal therapy. All patients had pre- and post-treatment serum prostate specific antigen (PSA) evaluation. They were followed up for at least 24 months. PSAD was defined as the ratio of pre-treatment serum PSA to the prostate volume, as determined from CT treatment planning scans. Prostate volumes were calculated using the prostate ellipse formula. Median PSA density was 0.37, with a range 0.01-6.7. Biochemical failure was defined as three consecutive rises in serum PSA, regardless of the magnitude of elevation. 4-year biochemical disease-free survival (BDFS) for patients with PSAD < or = 0.3 was 60%, compared with 22% for patients with PSAD > 0.3 (p = < 0.001). In a multivariate analysis, pre-treatment PSA (p = < 0.001), Gleason score (p = 0.002), and stage (p = 0.03) were independent predictors of BDFS, while PSAD was not an important prognosticator (p = 0.62). Pre-treatment serum PSA is the most important prognosticator of BDFS, following external beam radiotherapy, for patients with prostate cancer. PSA density did not predict treatment outcome.

The fate of 10-year clinically recurrence-free survivors after definitive radiotherapy for T1-3N0M0 prostate cancer

We recently reported the outcome of 168 patients treated with pelvic lymphadenectomy and definitive radiation therapy. This report is a subanalysis of those patients (pts) who were clinically without evidence of disease (NED) 10 years after a negative staging pelvic lymphadenectomy and definitive radiation therapy for prostate cancer. One hundred of our original cohort of 168 patients had at least ten year follow-up. 76 patients had pathologically negative lymph nodes and had not received hormonal therapy. Forty-two N0 patients with sufficient follow-up were alive and clinically NED 10 years post-operatively. Distribution by disease stage at diagnosis was: Stage A2: 12 pts; Stage B: 19 pts; Stage B2/C: 6 pts; Stage C: 5 pts. Median follow-up was 13.3 years, with a minimum follow-up of 10 years. Of the 42 patients clinically NED at 10 years, 5 pts died subsequently without PSA data, remaining clinically NED a median of 13 y 3 m postoperatively; 37 patients were alive and without evidence of disease off all therapy at 10 years post-operatively. Bone scans were performed on 8 of the 9 patients with PSA over 4.0 ng/ml or on hormonal therapy. These revealed a single patient with diffuse but asymptomatic bone metastases. Ultrasound-guided sextant biopsies were performed on one 78-year-old patient with elevated PSA 19 years post-operatively, revealing an asymptomatic local recurrence. Patients who survive clinically NED for 10 years have a low likelihood of clinical failure, even in the presence of PSA values between 4.0 and 10 ng/ml. In these patients, PSA trends are of greater utility than absolute values.

Radiation therapy or prostatectomy: an old conflict revisited in the PSA era. A radiation oncologist's viewpoint

A close examination of the outcomes for the radical treatment of prostate cancer in the prostate-specific antigen (PSA) era shows no clear advantage to radical prostatectomy over external-beam radiation. Both modalities are highly effective against small impalpable tumors of low Gleason grade and with PSA values less than 10 ng/mL. Both modalities struggle against all other stages of prostate cancer. Radiation and surgery are currently in states of rapid evolution, and the results emerging become quickly outdated. It is hoped that the newer, more aggressive approaches will help a significant number of patients, perhaps the majority, not currently being cured by radical therapy.

Radiotherapy options for localized prostate cancer based upon pretreatment serum prostate-specific antigen levels and biochemical control: a comprehensive review of the literature

PURPOSE

To review all the available radiotherapy (RT) literature on localized prostate cancer treatment where serum prostate-specific antigen (PSA) levels were used to both stratify patients and evaluate outcome and determine if any conclusions can be reached regarding an optimal radiotherapeutic management for this disease.

METHODS AND MATERIALS

A MEDLINE search was conducted to obtain all articles in English on prostate cancer treatment employing RT from 1986-1997. Studies were considered eligible for review only if they met all the following criteria: 1) pretreatment PSA values were recorded and grouped for subsequent evaluation, 2) posttreatment PSA values were continuously monitored, 3) definitions of biochemical control were stated, and 4) the median follow-up was given.

RESULTS

Of the 246 articles identified, only 20 met the inclusion criteria; 4 using conformal external beam RT, 8 using conventional external beam RT, and 8 using interstitial brachytherapy (4 using a permanent implant alone, 3 combining external beam RT with a permanent implant, and 1 combining a conformal temporary interstitial implant boost with external beam RT). No studies using neutrons (with or without external beam RT) or androgen deprivation (combined with external beam RT) were identified where patients were stratified by pretreatment PSA levels. Results for all therapies were extremely variable with the 3-5-year rates of biochemical control for patients with pretreatment PSA levels < or = 4 ng/ml ranging from 48 to 100%, for PSA levels >4 and < or = 10 ng/ml ranging from 44 to 90%, for PSA levels >10 and < or = 20 ng/ml ranging from 27 to 89%, and for PSA levels >20 ranging from 14 to 89%. The median Gleason score, T-stage, definition of biochemical control, and follow-up were substantially different from series to series. No RT option consistently produced superior results.

CONCLUSIONS

When data are reviewed from studies using serum PSA levels to stratify patients and to evaluate treatment outcome, no consistently superior RT technique was identified. These data suggest that standard definitions of disease stage (combining clinical, pathologic, and biochemical criteria) and a common definition of biochemical cure (as developed by the American Society for Therapeutic Radiology and Oncology Consensus Panel) need to be adopted to evaluate treatment efficacy and advise patients on the most appropriate radiotherapeutic option for their disease.

Preliminary outcomes following cryosurgical ablation of the prostate in patients with clinically localized prostate carcinoma

PURPOSE

Cryosurgical ablation of the prostate is a novel therapeutic modality that induces cell lysis in the prostate by direct application of low temperatures. We have been conducting an ongoing prospective pilot study of the use of cryosurgical prostate ablation in treating patients with nonmetastatic prostate adenocarcinoma since January 1993. Results in 145 consecutive patients with mean 36 months and minimum 12 months of followup are presented.

MATERIALS AND METHODS

Accrual was open to patients with clinical stages T1a to T3c prostate adenocarcinoma. Pelvic lymph node dissections were recommended but not required for patients with prostate specific antigen (PSA) greater than 15 ng./ml. before study entry. PSA changes, random prostate biopsy findings and morbidities after cryosurgical prostate ablation were recorded for each patient.

RESULTS

Overall actuarial rates at 42 months for maintaining PSA less than 0.3 and less than 1.0 were 59% and 66%, respectively. The overall actuarial progression-free rate at 60 months was 56%. Among 160 biopsies performed 16% showed some evidence of residual carcinoma. Overall crude rates of maintaining either a negative biopsy or PSA less than 0.3 at 6 and 24 months after cryosurgical prostate ablation were 87% and 73%, respectively. Significantly higher morbidities were seen in previously radiated patients undergoing cryosurgical prostate ablation compared to those with no prior radiation. Among nonradiated patients 85% experienced no significant morbidity after cryosurgical prostate ablation.

CONCLUSIONS

Although preliminary, short-term outcomes after cryosurgical prostate ablation appear to be comparable to identical outcomes reported for external beam radiotherapy. Based on these results cryosurgical prostate ablation appears to be an effective therapeutic alternative for treating patients with localized prostate adenocarcinoma.

Stage T1-2 prostate cancer with pretreatment prostate-specific antigen level < or = 10 ng/ml: radiation therapy or surgery?

PURPOSE

To detect differences in biochemical failure rates by treatment modality (radiation therapy or radical prostatectomy) in patients with early-stage prostate cancer presenting with pretreatment prostatic-specific antigen (PSA) levels < or = 10.0 ng/ml.

METHODS AND MATERIALS

A total of 1467 consecutive patients with prostate carcinoma were treated with either radiotherapy (RT) or radical prostatectomy (RP) between January 1987 and June 1996. Patients with the following were excluded from the present study: initial PSA (iPSA) level > 10 ng/ml (n = 444), clinical Stage T3 disease (n = 73), adjuvant or neoadjuvant treatment (n = 173), no available iPSA level (n = 31), no available biopsy Gleason score (GS) (n = 33), incomplete pathologic information (n = 16), and no available follow-up PSA levels (n = 90). The analysis was performed on 607 cases: 354 treated with RP and 253 with RT (median dose 68.4 Gy). The outcome of interest was biochemical relapse-free survival (bRFS), with biochemical relapse being defined as either a detectable PSA level after RP or elevation in PSA levels of > or = 1.0 ng/ml above the nadir after RT. Proportional hazards were used to analyze the effect of treatment modality and confounding variables (i.e., age, stage, biopsy GS, iPSA levels) on treatment outcome.

RESULTS

Seventy-nine percent of patients (n = 478) had clinical Stage T1 or T2A disease at presentation (RP vs. RT: 84% vs. 71%, p < 0.001). Twenty-one percent of patients (n = 127) had iPSA levels < or = 4 ng/ml (RP vs. RT: 24% vs. 17%, p = 0.027). Seventy-six percent of patients (n = 460) had biopsy GS < or = 6 (RP vs. RT: 79% vs. 71%, p = 0.014). The median follow-up time was 24 months (range 3-110). For the 607 patients, the 5-year bRFS rate was 76%. The 5-year RFS rates for RP versus RT were 76% versus 75%, respectively (p = 0.09). After adjustment for all confounding variables, iPSA levels (p < 0.001) and biopsy GS (p = 0.001) were the only independent predictors of relapse, whereas age, clinical stage, and treatment modality were not (p = 0.20; p = 0.09; and p = 0.10, respectively).

CONCLUSION

In patients with clinical Stage T1-2 prostate cancer and pretreatment PSA < or = 10 ng/ml, there is no difference in biochemical failure rates between those treated with radiation and those treated with surgery.

Prostate-specific antigen nadir of 0.5 ng/mL or less defines disease freedom for surgically staged men irradiated for prostate cancer

OBJECTIVES

This report describes treatment results of men with prostate cancer staged with a pelvic lymph node dissection. Disease freedom was defined by a prostate-specific antigen (PSA) level nadir of 0.5 ng/mL or less.

METHODS

Since 1984, 363 men with clinical Stage T1 or T2, surgical stage node-negative prostate cancer were simultaneously irradiated with a retropubic iodine 125 prostate implant followed by external-beam radiation. The average pretreatment PSA level was 13.6 ng/mL (median 8.5, range 0.3 to 188). Disease freedom was defined as the achievement and maintenance of a nadir of 0.5 ng/mL or less. Treatment failure was defined as a nadir of more than 0.5 ng/mL or a PSA rise above this level. The median follow-up is 5 years (average 5.5, range 1 to 12.5).

RESULTS

For all men, the 5- and 10-year disease-free survival results are 78% and 65%. Of 201 men with a minimum 5-year follow-up, 140 (70%) are disease free. The 5-year disease-free survival rate by pretreatment PSA is 4.0 ng/mL or less, 93%; 4.1 to 10.0 ng/mL, 87%; 10.1 to 20.0 ng/mL, 72%; and greater than 20.0 ng/mL, 45%.

CONCLUSIONS

The 10-year disease-free survival results of retropubic implantation, a technique considered a failure by many investigators, followed by external-beam radiation appear to be better than either technique given separately and are comparable to the results following radical prostatectomy. These results are valuable because they form a baseline that may be improved upon in the future by simultaneous irradiation using the transperineal implant technique.

Prostate-specific antigen after radiation therapy. Prognosis by pretreatment level and post-treatment nadir

After external beam radiation therapy, pretreatment prostate-specific antigen (PSA) is the most powerful predictor of outcome as measured PSA (biochemical) failure. The post-treatment nadir levels of PSA that predict best for subsequent freedom from PSA failure are debatable, and many nadir levels have been proposed as targets. Although lower nadirs generally are associated with superior outcomes, the identification of a single absolute nadir level was not selected at a recent ASTRO consensus conference. Rather, three consecutive PSA rises above the nadir, with date of failure at the midpoint between the nadir and first rise, were selected as a more useful end point for treatment failure.

Equivalent biochemical failure-free survival after external beam radiation therapy or radical prostatectomy in patients with a pretreatment prostate specific antigen of > 4-20 ng/ml

PURPOSE

Biochemical failure-free survival stratified by the pretreatment prostate-specific antigen (PSA) and biopsy Gleason score (bGl) is determined for prostate cancer patients managed definitively with external beam radiation therapy or radical retropubic prostatectomy.

METHODS AND MATERIALS

A Cox regression multivariable analysis evaluating the variables of PSA, bGl, and clinical stage was used to evaluate the end point of time to PSA failure in 867 and 757 consecutive prostate cancer patients managed definitively with external beam radiation therapy or radical retropubic prostatectomy, respectively. PSA failure-free survival was determined using Kaplan-Meier analysis. Comparisons were made using the log rank test.

RESULTS

The pretreatment PSA, bGl, and clinical stage (T3,4 vs. T1,T2) were found to be independent predictors of time to post-treatment PSA failure for both surgically and radiation managed patients using Cox regression multivariable analysis. Patients with a pretreatment PSA of > 4 ng/ml and < or = 20 ng/ml could be classified into risk groups for time to post-therapy PSA failure: low = PSA > 4-10 ng/ml and bGl < or = 4; intermediate = PSA > 4-10 and bGl 5-7; or PSA > 10-20 ng/ml and bGl < or = 7; high = PSA > 4-20 ng/ml and bGl > or = 8. Two-year PSA failure-free survival for surgically managed and radiation-managed patients, respectively, were 98% vs. 92% (p = 0.45), 77% vs. 81% (p = 0.86), and 51% vs. 53% (p = 0.48) for patients at low, intermediate, and high risk for post-therapy PSA failure.

CONCLUSIONS

There was no statistical difference in the 2-year PSA failure-free survival for potentially curable patients managed definitively with surgery or radiation therapy when a retrospective comparison stratifying for the pretreatment PSA and bGl was performed.

Neoadjuvant androgen suppression with radiation in the management of locally advanced adenocarcinoma of the prostate: experimental and clinical results

Conventional radiotherapy has been a standard treatment for the management of locally advanced T2c-4 prostatic carcinoma for over 2 decades. The routine use of serum PSA in follow-up makes it clear that > 80% of these patients will show evidence of failure by 10 years. Rebiopsy of those with a rising PSA shows locally persistent disease in the majority of cases. Increasing the radiation dose applied to the prostate increases local control but at the risk of higher morbidity. Experimental data using the Shionogi tumor mouse model suggest a potential gain from neoadjuvant androgen suppression without any increase in normal tissue morbidity. Two randomized trials comparing neoadjuvant androgen suppression prior to radiation therapy with radiation alone in humans show considerable short-term gains in local control and disease-free survival but mature data are still awaited. It is currently unknown whether the positive interaction between radiation and androgen suppression is synergistic or simply additive.

The PSA nadir that indicates potential cure after radiotherapy for prostate cancer

OBJECTIVES

The prostate-specific antigen nadir that indicates potential cure by radiotherapy has never been established. We determined this nadir level and used it to define precisely disease freedom after radiotherapy.

METHODS

Combination radioactive 125I prostate implant followed by external-beam radiation was administered to 660 men with clinical Stage T1T2N0 prostate cancer. The average pretreatment prostate-specific antigen level (Tandem R Assay) was 11.7 ng/mL (median 8.0 ng/mL, range 0.3 to 188 ng/mL). To analyze these data, recurrence was defined as a prostate-specific antigen level rising above whatever nadir was achieved. The median follow-up is 42 months (range 12 to 150 months).

RESULTS

Eighty-one percent of all men are calculated to achieve a prostate-specific antigen nadir of 0.5 ng/mL or less and to have a 5- and 10-year disease-free survival rate of 93% and 83%, respectively, as compared with a 5-year disease-free survival rate of 26% for those achieving a nadir of 0.6 to 1.0 ng/mL--a significant difference (P = 0.0001). All men with a nadir greater than 1.0 ng/mL ultimately failed treatment. Of 201 men with a minimum 5-year follow-up, 143 are disease-free and 140 (98%) achieved and maintained a nadir of 0.5 ng/mL or less.

CONCLUSIONS

For possible cure of prostate cancer with radiotherapy, a prostate-specific antigen nadir of 0.5 ng/mL or less should be achieved. With this nadir level, disease freedom after irradiation is defined as achievement and maintenance of a nadir of 0.5 ng/mL or less. A nadir greater than 0.5 ng/mL or subsequent increase above 0.5 ng/mL is defined as irradiation treatment failure. This definition may help resolve the controversy about the potential for cure of prostate cancer by irradiation.