High PSA anxiety and low health literacy skills: drivers of early use of salvage ADT among men with biochemically recurrent prostate cancer after radiotherapy?

BACKGROUND: Although commonly used, early initiation of salvage androgen deprivation therapy (ADT) has not been proven to enhance survival. We evaluated whether prostate-specific antigen (PSA) anxiety or health literacy are associated with use of early salvage ADT among men with recurrent prostate cancer after radiotherapy. PATIENTS AND METHODS: The prospective Comprehensive, Observational, Multicenter, Prostate Adenocarcinoma Registry was used to study 375 men with biochemically recurrent prostate cancer after external beam radiation or brachytherapy. Multivariable logistic regression was used to determine whether PSA anxiety and health literacy are associated with salvage ADT as initial management after biochemical recurrence. RESULTS: Sixty-eight men (18.1%) received salvage ADT as initial management for PSA recurrence. Men with high PSA anxiety were twice as likely to receive salvage ADT compared with men who did not have high PSA anxiety on both univariable [28.8% versus 13.1%; odds ratio (OR) 2.15; 95% confidence interval (CI) 1.16-4.00; P = 0.015] and multivariable analysis [adjusted OR (AOR) 2.36; 95% CI 1.21-4.62; P = 0.012]. Furthermore, men who had higher levels of health literacy were nearly half as likely to undergo salvage ADT compared with men who had lower levels of health literacy on univariable analysis (15.2% versus 26.3%; OR 0.50; 95% CI 0.29-0.88; P = 0.016), with a trend toward this association on multivariable analysis (AOR 0.58; 95% CI 0.32-1.05; P = 0.07). CONCLUSIONS: Among men with PSA recurrence after radiotherapy, odds of use of salvage ADT were nearly twice as great among men with high PSA anxiety or low health literacy, suggesting that these men are receiving higher rates of unproven treatment. Given that early salvage ADT is costly, worsens quality of life, and has not been shown to improve survival, quality improvement strategies are needed for these individuals.

A refined risk stratification scheme for clinical stage 1 NSGCT based on evaluation of both embryonal predominance and lymphovascular invasion.

BACKGROUND: Active surveillance is an increasingly accepted approach for managing patients with germ-cell tumors (GCTs) after an orchiectomy. Here we investigate a time-to-relapse stratification scheme for clinical stage 1 (CS1) nonseminoma GCT (NSGCT) patients according to factors associated with relapse and identify a group of patients with a lower frequency and longer time-to-relapse who may require an alternative surveillance strategy. PATIENTS AND METHODS: We analyzed 266 CS1 GCT patients from the IRB-approved DFCI GCT database that exclusively underwent surveillance following orchiectomy from 1997 to 2013. We stratified NSGCT patients according to predominance of embryonal carcinoma (EmbP) and lymphovascular invasion (LVI), using a 0, 1, and 2 scoring system. Cox regression and conditional risk analysis were used to compare each NSGCT group to patients in the seminomatous germ-cell tumor (SGCT) category. Median time-to-relapse values were then calculated among those patients who underwent relapse. Relapse-free survival curves were generated using the Kaplan-Meier method. RESULTS: Fifty (37%) NSGCT and 20 (15%) SGCT patients relapsed. The median time-to-relapse was 11.5 versus 6.3 months for the SGCT and NSGCT groups, respectively. For NSGCT patients, relapse rates were higher and median time-to-relapse faster with increasing number of risk factors (RFs). Relapse rates (%) and median time-to-relapse (months) were 25%/8.5 months, 41%/6.8 months and 78%/3.8 months for RF0, RF1 and RF2, respectively. We found a statistically significant difference between SGCT and patients with one or two RFs (P < 0.001) but not between SGCT and NSGCT RF0 (P = 0.108). CONCLUSION: NSGCT patients grouped by a risk score system based on EmbP and LVI yielded three groups with distinct relapse patterns -and patients with neither EmbP nor LVI appear to behave similar to SGCT.

Incidence and determinants of 1-month mortality after cancer-directed surgery.

BACKGROUND: Death within 1 month of surgery is considered treatment related and serves as an important health care quality metric. We sought to identify the incidence of and factors associated with 1-month mortality after cancer-directed surgery. PATIENTS AND METHODS: We used the Surveillance, Epidemiology and End Results Program to study a cohort of 1 110 236 patients diagnosed from 2004 to 2011 with cancers that are among the 10 most common or most fatal who received cancer-directed surgery. Multivariable logistic regression analyses were used to identify factors associated with 1-month mortality after cancer-directed surgery. RESULTS: A total of 53 498 patients (4.8%) died within 1 month of cancer-directed surgery. Patients who were married, insured, or who had a top 50th percentile income or educational status had lower odds of 1-month mortality from cancer-directed surgery {[adjusted odds ratio (AOR) 0.80; 95% confidence interval (CI) 0.79-0.82; P < 0.001], (AOR 0.88; 95% CI 0.82-0.94; P < 0.001), (AOR 0.95; 95% CI 0.93-0.97; P < 0.001), and (AOR 0.98; 95% CI 0.96-0.99; P = 0.043), respectively}. Patients who were non-white minority, male, or older (per year increase), or who had advanced tumor stage 4 disease all had a higher risk of 1-month mortality after cancer-directed surgery, with AORs of 1.13 (95% CI 1.11-1.15), P < 0.001; 1.11 (95% CI 1.08-1.13), P < 0.001; 1.02 (95% 1.02-1.03), P < 0.001; and 1.89 (95% CI 1.82-1.95), P < 0.001 respectively. CONCLUSIONS: Unmarried, uninsured, non-white, male, older, less educated, and poorer patients were all at a significantly higher risk for death within 1 month of cancer-directed surgery. Efforts to reduce 1-month surgical mortality and eliminate sociodemographic disparities in this adverse outcome could significantly improve survival among patients with cancer.

Determining optimal eluter design by modeling physical dose enhancement in brachytherapy.

PURPOSE: In situ drug release concurrent with radiation therapy has been proposed to enhance the therapeutic ratio of permanent prostate brachytherapy. Both brachytherapy sources and brachytherapy spacers have been proposed as potential eluters to release compounds, such as nanoparticles or chemotherapeutic agents. The relative effectiveness of the approaches has not been compared yet. This work models the physical dose enhancement of implantable eluters in conjunction with brachytherapy to determine which delivery mechanism provides greatest opportunity to enhance the therapeutic ratio. MATERIALS AND METHODS: The combined effect of implanted eluters and radioactive sources were modeled in a manner that allowed the comparison of the relative effectiveness of different types of implantable eluters over a range of parameters. Prostate geometry, source, and spacer positions were extracted from treatment plans used for 125 I permanent prostate implants. Compound concentrations were calculated using steady-state solution to the diffusion equation including an elimination term characterized by the diffusion-elimination modulus (ϕb ). Does enhancement was assumed to be dependent on compound concentration up to a saturation concentration (csat ). Equivalent uniform dose (EUD) was used as an objective to determine the optimal configuration of eluters for a range of diffusion-elimination moduli, concentrations, and number of eluters. The compound delivery vehicle that produced the greatest enhanced dose was tallied for points in parameter space mentioned to determine the conditions under whether there are situations where one approach is preferable to the other. RESULTS: The enhanced effect of implanted eluters was calculated for prostate volumes from 14 to 45 cm3 , ϕb from 0.01 to 4 mm-1 , csat from 0.05 to 7.5 times the steady-state compound concentration released from the surface of the eluter. The number of used eluters (ne ) was simulated from 10 to 60 eluters. For the region of (csat , Φ)-space that results in a large fraction of the gland being maximally sensitized, compound eluting spacers or sources produce equal increase in EUD. In the majority of the remaining (csat , Φ)-space, eluting spacers result in a greater EUD than sources even where sources often produce greater maximal physical dose enhancement. Placing eluting implants in planned locations throughout the prostate results in even greater enhancement than using only source or spacer locations. CONCLUSIONS: Eluting brachytherapy spacers offer an opportunity to increase EUD during the routine brachytherapy process. Incorporating additional needle placements permits compound eluting spacer placement independent of source placement and thereby allowing a further increase in the therapeutic ratio. Additional work is needed to understand the in vivo spatial distribution of compound around eluters, and to incorporate time dependence of both compound release and radiation dose.

The impact of comorbidity and PSA doubling time on the risk of death in men experiencing PSA failure following radiation therapy with or with androgen deprivation therapy for unfavorable-risk prostate cancer.

BACKGROUND: The optimal management of men with PSA failure following initial prostate cancer (PC) therapy stratified by comorbidity is unknown. We investigated the impact that PSA doubling time (DT) and comorbidity had on the risk of all-cause mortality (ACM), prostate cancer-specific mortality (PCSM) and other-cause mortality (OCM) following PSA failure. METHODS: Between 1995 and 2001, 206 men with unfavorable-risk PC were randomized to receive radiation therapy alone or in combination with 6 months of androgen deprivation therapy (ADT); 108 men experienced PSA failure and formed the study cohort. Cox and Fine-Gray regression analysis was used to determine whether PSA DT was associated with the risk of ACM and PCSM/OCM, respectively, stratified by comorbidity status using a validated metric. RESULTS: After a median follow-up of 13.71 years following PSA failure, 81 of the 108 men (75%) died. Longer PSA DT was associated with a decreased risk of PCSM in men with no/minimal (adjusted hazard ratio (AHR) 0.33, 95% confidence interval (CI) 0.17-0.65, P=0.001) and moderate/severe comorbidity (AHR 0.014, 95% CI 0.002-0.129, P=0.0002). However, because of the different contributions of the risk of OCM to risk of ACM within comorbidity subgroups, increasing PSA DT was only associated with a decreased risk of ACM in men with no/minimal (AHR 0.69, 95% CI 0.50-0.96, P=0.03) but not moderate/severe comorbidity (AHR 0.95, 95% CI 0.51-1.78, P=0.87). CONCLUSIONS: Both the extent of comorbidity and the PSA DT should be taken into consideration when deciding on appropriate management and/or clinical trial eligibility at the time of PSA failure.

Duration of the anti-androgen in men undergoing 6 months of an LHRH agonist and radiation therapy for unfavorable-risk prostate cancer and the risk of death.

BACKGROUND: Whether adding a first-generation anti-androgen (AA) to a luteinizing hormone-releasing hormone agonist in the radiotherapeutic management of unfavorable-risk prostate cancer (PC) reduces the risk of all-cause and PC-specific mortality (ACM and PCSM) among men within differing comorbidity subgroups is unknown. METHODS: Between 1995 and 2001, 206 men with unfavorable-risk PC were enrolled in a randomized trial comparing radiation with or without 6 months of androgen-deprivation therapy (ADT). Partial AA use (median: 4.2 months) occurred in 29 of the 102 men randomized to ADT. Cox, and Fine and Gray's regressions were used to evaluate the impact of full versus partial AA use on PCSM and ACM-risk within comorbidity subgroups. RESULTS: After a median follow-up of 16.62 years, 156 men died. In men with moderate to severe comorbidity increasing death was observed as treatment transitioned from no to partial to full ADT (P=0.02) with an increased ACM-risk with full versus partial AA use (adjusted hazard ratio (AHR), 2.25 (95% confidence interval (CI), 0.94-5.41); P=0.07); whereas only 1 and no PC deaths occurred in men receiving a partial versus full AA course, respectively. Among men with no or minimal comorbidity there was no decrease in ACM (AHR, 0.97 (95% CI, 0.49-1.91); P=0.92) or PCSM-risk (AHR 0.39 (95% CI 0.07-52.18); P=0.28) in comparing full versus partial AA use. CONCLUSION: Increasing AA use by 2 months does not appear to impact survival in men with localized unfavorable-risk PC and no or minimal comorbidity, but may shorten survival in men with moderate to severe comorbidity, raising concern regarding in whom and for how long the AA should be prescribed.

Which, when and why? Rational use of tissue-based molecular testing in localized prostate cancer.

An increased molecular understanding of localized prostate cancer and the improved ability for molecular testing of pathologic tissue has led to the development of multiple clinical assays. Here we review the relevant molecular biology of localized prostate cancer, currently available tissue-based tests and describe which is best supported for use in various clinical scenarios. Literature regarding testing of human prostate cancer tissue with Ki-67, PTEN (by immunohistochemistry (IHC) or fluroescence in situ hybridization (FISH)), ProMark, Prolaris, OncotypeDX Prostate and Decipher was reviewed to allow for generation of expert opinions. At diagnosis, evaluation of PTEN status, use of ProMark or OncotypeDX Prostate in men with Gleason 6 or 3+4=7 disease may help guide the use of active surveillance. For men with Gleason 7 or above disease considering watchful waiting, Ki-67 and Prolaris add independent prognostic information. For those men who have undergone prostatectomy and have adverse pathology, Decipher testing may aid in the decision to undergo adjuvant radiation. Newly available molecular tests bring opportunities to improve decision making for men with localized prostate cancer. A review of the currently available data suggests clinical scenarios for which each of these tests may have the greatest utility.

Role of interstitial radiotherapy in the management of clinically organ-confined prostate cancer: the jury is still out.

PURPOSE AND DESIGN: To discuss the evolution of the use of brachytherapy in the treatment of clinically organ-confined prostate cancer and to review modern techniques, results of therapy, and optimal patient selection criteria. RESULTS: Using modern localization and immobilization techniques, interstitial prostate radiotherapy for patients with a prostate-specific antigen (PSA) level less than 10 ng/mL yields an at least 87% rate of freedom from biochemical relapse at 3 years, which is numerically equivalent to results achieved with external-beam radiotherapy or radical prostatectomy. With a minimum median follow-up time of 24 months, 81% to 85% (2-year actuarial and 3-year crude) potency rates have been reported concomitant with 2-year actuarial rates of 12% for grade > or = 2 rectal complications and 10% for grade > or = 3 urethral complications. CONCLUSION: The combination of clinical stage, PSA level, and biopsy Gleason sum allows for selection of patients with the highest probability of having all of the prostate cancer encompassed by the high-dose implant volume, while simultaneously respecting the normal-tissue tolerance doses of the juxtaposed normal tissues (rectum and bladder). In particular, patients with nonpalpable (T1c) lesions, a biopsy Gleason sum < or = 6 (ideally < or = 4), and a PSA level less than 10 ng/mL represent the optimal implant candidates. Differential loading of the implant away from the geometric center and not accepting patients with large prostate glands (> or = 60 cm3) or history of a transurethral resection of the prostate (TURP) as implant candidates, may reduce urethral toxicity. Further follow-up evaluation of prostate cancer patients treated with interstitial radiotherapy will verify if favorable potency preservation rates and rates of freedom from biochemical failure equivalent to those achieved with radical prostatectomy or external-beam radiation therapy are maintained.

Prostate-specific antigen failure despite pathologically organ-confined and margin-negative prostate cancer: the basis for an adjuvant therapy trial.

PURPOSE: A multivariable analysis to evaluate the potential clinical and pathologic factors that predict for early biochemical failure in patients with pathologically organ-confined and margin-negative disease was performed to define patients who may benefit from adjuvant therapy. PATIENTS AND METHODS: Three hundred forty-one prostate cancer patients treated with a radical retropubic prostatectomy between January 1989 and June 1995 and found to have pathologically organ-confined and margin-negative disease comprised the study population. A logistic regression multivariable analysis to evaluate the predictive value of the preoperative prostate-specific antigen (PSA) level, pathologic (prostatectomy) Gleason score, and pathologic stage on PSA failure occurring during the first postoperative year was performed. RESULTS: Predictors of PSA failure during the first postoperative year in patients with pathologically organ-confined disease included pathologic Gleason score > or = 7 (P = .0007) and preoperative PSA level greater than 10 (P < .0001). Corresponding 3-year freedom-from-PSA-failure rates for these pathologic organ-confined patients with both, one, or neither of these factors were 60%, 75% to 84%, and 95%, respectively (P < .0001). CONCLUSION: Prostate cancer patients with pathologically organ-confined and margin-negative disease and a preoperative PSA level greater than 10 ng/mL or a pathologic Gleason score > or = 7 have significant decrements in short-term PSA-failure-free survival. Therefore, these patients should be considered for adjuvant therapy in the setting of a phase III clinical trial.

Clinical utility of the percentage of positive prostate biopsies in defining biochemical outcome after radical prostatectomy for patients with clinically localized prostate cancer.

PURPOSE: To determine the clinical utility of the percentage of positive prostate biopsies in predicting prostate-specific antigen (PSA) outcome after radical prostatectomy (RP) for men with PSA-detected or clinically palpable prostate cancer. METHODS: A Cox regression multivariable analysis was used to determine whether the percentage of positive prostate biopsies provided clinically relevant information about PSA outcome after RP in 960 men while accounting for the previously established risk groups that are defined according to pretreatment PSA level, biopsy Gleason score, and the 1992 American Joint Committee on Cancer (AJCC) clinical T stage. The findings were then tested using an independent surgical database that included data for 823 men. RESULTS: Controlling for the known prognostic factors, the percentage of positive prostate biopsies added clinically significant information (P <.0001) regarding time to PSA failure after RP. Specifically, 80% of the patients in the intermediate-risk group (1992 AJCC T2b, or biopsy Gleason 7 or PSA > 10 ng/mL and

Critical analysis of the ability of the endorectal coil magnetic resonance imaging scan to predict pathologic stage, margin status, and postoperative prostate-specific antigen failure in patients with clinically organ-confined prostate cancer.

PURPOSE: To determine whether there is a role for endorectal coil magnetic resonance imaging (erMRI) in the prediction of pathologic stage, margin status, and/or postoperative prostate-specific antigen (PSA) failure in patients with clinically organ-confined prostate cancer. PATIENTS AND METHODS: Using erMRI, the radiologic-pathologic correlation of extracapsular extension (ECE) and seminal vesicle invasion (SVI) was evaluated in 445 surgically managed patients. Logistic regression multivariable analysis was applied to the clinical stage, PSA, biopsy Gleason grade, and erMRI findings to assess the outcomes of ECE, SVI, positive surgical margins (PSM), and postoperative PSA failure. RESULTS: The accuracy of erMRI to predict for ECE and SVI numerically decreased with both increasing PSA and biopsy Gleason score because of the increasing false-negative scans in cases of microscopic transcapsular or seminal vesicle disease. Of patients who could not be categorized into low or high risk for postoperative PSA failure on the basis of clinical stage, preoperative PSA, and biopsy Gleason score, a negative or positive erMRI for ECE or SVI stratified these patients into groups with a 78% versus 21% (P < .0001) 3-year rate of actuarial freedom from PSA failure. In this subgroup, the overall accuracy of the erMRI was 70% +/- 6% and 94% +/- 2% for ECE and SVI, respectively. The most significant predictor on multivariable analysis of PSM was the erMRI finding of ECE (P = .0001). CONCLUSION: This initial report suggests that a preoperative erMRI can identify clinically organ-confined prostate cancer patients at high risk for having ECE, SVI, and PSM that otherwise would be missed on the basis of the clinical stage, preoperative PSA, and biopsy Gleason score. Confirmatory studies are needed.

Utilizing predictions of early prostate-specific antigen failure to optimize patient selection for adjuvant systemic therapy trials.

PURPOSE: Prostate-specific antigen (PSA) failure within 2 years after radical prostatectomy (RP) has been shown to be a clinically significant predictor of distant failure. This study was performed to estimate 2-year PSA failure rates on the basis of readily available clinical and pathologic factors to identify patients for whom effective adjuvant systemic therapy is needed. PATIENTS AND METHODS: A Cox regression multivariable analysis was used to determine whether the percentage of positive prostate biopsies, PSA level, and the pathologic findings at RP in 1,728 men provided clinically relevant information about PSA outcome after RP. A bootstrapping technique with 2,000 replications was used to provide 95% confidence intervals for the predicted 2-year PSA failure rates, which were determined on the basis of the independent clinical and pathologic predictors of PSA outcome. RESULTS: The independent predictors of time to PSA failure included a percentage of positive prostate biopsies of greater than 34% (P: < or =.009), PSA level greater than 10 ng/mL (P: < or =.01), seminal vesicle invasion (P: =. 02), prostatectomy Gleason score of 8 to 10 (P: =.04), and positive surgical margins (P: =.0001). Predictions of 2-year PSA failure rates and bootstrap estimates of the 95% confidence intervals were arranged in a tabular format, stratified by independent clinical and pathologic predictors of PSA outcome. CONCLUSION: Patients who are most likely to benefit from effective adjuvant systemic therapy after RP can be identified using readily available clinical and pathologic data.

Pretreatment nomogram for prostate-specific antigen recurrence after radical prostatectomy or external-beam radiation therapy for clinically localized prostate cancer.

PURPOSE: To present nomograms providing estimates of prostate-specific antigen (PSA) failure-free survival after radical prostatectomy (RP) or external-beam radiation therapy (RT) for men diagnosed during the PSA era with clinically localized disease. PATIENTS AND METHODS: A Cox regression multivariable analysis was used to determine the prognostic significance of the pretreatment PSA level, 1992 American Joint Committee on Cancer (AJCC) clinical stage, and biopsy Gleason score in predicting the time to posttherapy PSA failure in 1,654 men with T1c,2 prostate cancer managed with either RP or RT. RESULTS: Pretherapy PSA, AJCC clinical stage, and biopsy Gleason score were independent predictors (P < .0001) of time to posttherapy PSA failure in patients managed with either RP or RT. Two-year PSA failure rates derived from the Cox regression model and bootstrap estimates of the 95% confidence intervals are presented in the format of a nomogram stratified by the pretreatment PSA, AJCC clinical stage, biopsy Gleason score, and local treatment modality. CONCLUSION: Men at high risk (> 50%) for early (< or = 2 years) PSA failure could be identified on the basis of the type of local therapy received and the clinical information obtained as part of the routine work-up for localized prostate cancer. Selection of these men for trials evaluating adjuvant systemic and improved local therapies may be justified.

Calculated prostate cancer volume greater than 4.0 cm3 identifies patients with localized prostate cancer who have a poor prognosis following radical prostatectomy or external-beam radiation therapy.

PURPOSE: Patients with palpable extraprostatic disease (T3) have a poor prostate-specific antigen (PSA) failure-free (bNED) survival rate after radical prostatectomy (RP) or external-beam radiation therapy (RT). This study was performed to validate or refute the prognostic value of the previously defined calculated prostate cancer volume (cV(Ca)). PATIENTS AND METHODS: For patients with clinically localized disease (T1c,2), a Cox regression multivariable analysis was used to assess the ability of the cV(Ca) value to predict time to posttherapy PSA failure following RP or RT. RESULTS: The cV(Ca) value was a significant predictor (P < or = .0005) of time to posttherapy PSA failure in both an RP and RT data set independent of the one used to derive the cV(Ca)-based clinical staging system. In both RP- and RT-managed patients, estimates of 3-year bNED survival were not statistically different for patients with either T1c,2 disease and a cV(Ca) greater than 4.0 cm3 (RP, 27%; RT, 18%) or T3 disease (RP, 37%; RT, 34%). Despite pathologic T2 disease, the 3-year estimate of bNED survival was at most 51% in RP-managed patients with T1c,2 disease and cV(Ca) greater than 4.0 cm3. CONCLUSION: A cV(Ca) greater than 4.0 cm3 identified patients with T1c.2 disease whose bNED survival was poor after RT or RP despite pathologic T2 disease that suggests the presence of occult micrometastatic disease in many of these patients. Prospective randomized trials to evaluate the impact on survival of adjuvant systemic therapy in these high-risk patients are justified.

The association between race and treatment regret among men with recurrent prostate cancer.

BACKGROUND: To examine the impact of race on treatment regret among men with recurrent prostate cancer after surgery or radiation. METHODS: The prospective Comprehensive, Observational, Multicenter, Prostate Adenocarcinoma (COMPARE) registry was used to study a cohort of 484 men with biochemically recurrent prostate cancer after radical prostatectomy, external beam radiation or brachytherapy. Multivariable logistic regression was used to model the association between race and treatment regret and to determine whether there was an interaction between race and sexual problems after treatment with regards to treatment regret. RESULTS: Black men (N=78) were significantly more likely to have treatment regret when compared with non-black men (N=406; 21.8% versus 12.6%) on univariable analysis (odds ratio (OR) 1.94; 95% confidence interval 1.05-3.56; P=0.03). On multivariable analysis, black race trended towards but was no longer significantly associated with an increase in treatment regret (adjusted OR (AOR) 1.84 (0.95-3.58); P=0.071). There was an interaction between race and sexual problems after treatment (Pinteraction=0.02) such that among those without sexual problems, black men had more treatment regret than non-black men (26.7% versus 8.4%: AOR 4.68 (1.73-12.63); P=0.002), whereas among those with sexual problems, there was no difference in treatment regret between black and non-black men (18.8% versus 17.3%: AOR 1.04 (0.44-2.46); P=0.93). CONCLUSIONS: Among men with recurrent prostate cancer after surgery or radiation, black men were nearly twice as likely to experience treatment regret. Treating physicians should ensure that patients are fully apprised of the pros and cons of all treatment options to reduce the risk of subsequent regret.

Prostate cancer volume adds significantly to prostate-specific antigen in the prediction of early biochemical failure after external beam radiation therapy.

PURPOSE: A new clinical pretreatment quantity that closely approximates the true prostate cancer volume is defined. METHODS AND MATERIALS: The cancer-specific prostate-specific antigen (PSA), PSA density, prostate cancer volume (VCa), and the volume fraction of the gland involved with carcinoma (VCafx) were calculated for 227 prostate cancer patients managed definitively with external beam radiation therapy. 1. PSA density = PSA/ultrasound prostate gland volume. 2. Cancer-specific PSA = PSA - [PSA from benign epithelial tissue] 3. VCa = Cancer-specific PSA/[PSA in serum per cm3 of cancer] 4. VCafx = VCa/ultrasound prostate gland volume A Cox multiple regression analysis was used to test whether any of these clinical pretreatment parameters added significantly to PSA in predicting early postradiation PSA failure. RESULTS: The prostate cancer volume (p = 0.039) and the volume fraction of the gland involved by carcinoma (p = 0.035) significantly added to the PSA in predicting postradiation PSA failure. Conversely, the PSA density and the cancer-specific PSA did not add significantly (p > 0.05) to PSA in predicting postradiation PSA failure. The 20-month actuarial PSA failure-free rates for patients with calculated tumor volumes of < or = 0.5 cm3, 0.5-4.0 cm3, and > 4.0 cm3 were 92, 80, and 47%, respectively (p = 0.00004). CONCLUSION: The volume of prostate cancer (VCa) and the resulting volume fraction of cancer both added significantly to PSA in their ability to predict for early postradiation PSA failure. These new parameters may be used to select patients in prospective randomized trials that examine the efficacy of combining radiation and androgen ablative therapy in patients with clinically localized disease, who are at high risk for early postradiation PSA failure.

Optimizing target coverage by dosimetric feedback during prostate brachytherapy.

PURPOSE: Postimplant dosimetry of permanent prostate implants shows a loss of coverage compared to the preplan. One contributing factor is needle misplacement. The significance of needle misplacement and the clinical utility of dosimetric feedback were analyzed in the setting of interventional magnetic resonance (IMR) guided prostate brachytherapy. METHODS AND MATERIALS: Information provided by an intraoperative planning system was analyzed for 10 patients. Needle misplacement was measured and the dosimetric consequences calculated. Additional catheters and sources were placed following the insertion of all planned catheters to compensate for nonideal needle placement. RESULTS: Source misplacement ranged from 0.0 to 1.0 cm (median, 0.3 cm). The resulting loss of coverage ranged from 1% to 13%, and the intraoperative dosimetric feedback allowed a recovery of from 0% to 12% coverage. Between 0 and 3 (median, 2) additional needles and from 0 to 10 (median, 8) additional sources were required to restore coverage of the target. Final planned coverage exceeded 94% for all patients. CONCLUSION: The discrepancy between planned and achieved needle placement leads to a loss of dosimetric coverage of the target volume. Dosimetric feedback allows compensation for needle divergence. The technique of real-time dosimetric feedback does not require an IMR system, and could be generalized to ultrasound-guided implants.

A method for determining a prostate-specific antigen cure after radiation therapy for clinically localized prostate cancer.

PURPOSE: A method that allows the determination of a prostate-specific antigen (PSA) cure after definitive management for prostate carcinoma with radiation therapy is presented and tested. METHODS AND MATERIALS: The method involves a calculation of the patient's theoretical baseline PSA prior to the development of prostate cancer by using three serial rising PSA determinations obtained prior to the institution of therapy. The rate of rise of the PSA prior to therapy and the rate of decline of the PSA posttherapy are calculated, using an exponential model. Two criteria must be satisfied to define a PSA cure. First, the PSA nadir after treatment should be less than the calculated theoretical baseline PSA. Second, the rate of decline of PSA posttreatment should be greater than the rate of rise of the PSA prior to treatment. RESULTS: Applying these two criteria to the patient data base (n = 16) at a median follow-up of 19 months enabled the accurate prediction of 6 out of 6 (100%) of patients with documented PSA failure and 7 out of 10 (70%) of patients without PSA failure. Therefore, despite short follow-up, all six patients with PSA failure were predicted. Further follow-up is needed to ascertain if the seven patients predicted to be cured will remain PSA failure free and if the three patients currently without PSA failure in whom the model predicts failure, will subsequently fail. CONCLUSION: Therefore, using each patient's PSA history as the natural control may eliminate the error that is introduced with defining a PSA cure by using a single value for the PSA nadir at a specified time after radiation therapy.

Optimizing patient selection for prostate monotherapy.

PURPOSE: Patients at low risk for prostate-specific antigen (PSA) failure following definitive local therapy are those with PSA of 10 or less, biopsy Gleason Score of 6 or less, and 1992 American Joint Committee on Cancer (AJCC) clinical Stage T1c or T2a. However, low-risk patients managed with radical prostatectomy and found to have prostatectomy Gleason score > or = 3+4 have a less favorable PSA outcome when compared to patients with prostatectomy Gleason score < or = 3+3. This study was performed to determine whether the percentage of positive prostate biopsy cores could predict upgrading from a biopsy Gleason score of 6 or less to a prostatectomy Gleason score > or = 3+4 in low-risk patients to optimize selection for prostate only radiation therapy. METHODS AND MATERIALS: Concordance testing of the biopsy Gleason score and the primary and secondary prostatectomy Gleason grades was performed in 427 prostate cancer patients treated with radical prostatectomy and at low risk for PSA failure. Logistic regression multivariable analysis was performed to test the ability of the established prognostic factors and the percentage of positive prostate biopsies (<34%, 34-50%, >50%) to predict for upgrading from biopsy Gleason score of 6 or less prostatectomy Gleason score > or = 3+4. PSA failure-free survival was reported using the actuarial method of Kaplan and Meier and comparisons were made using a log-rank test. RESULTS: Twenty-nine percent of the 427 study patients were upgraded from a biopsy Gleason score of 6 or less to a prostatectomy Gleason score > or = 3+4. The presence of greater than 50% positive biopsies was the only significant factor for predicting the upgrading from biopsy Gleason score of 6 or less to prostatectomy Gleason score > or = 3+4 on logistic regression multivariable analysis with the variables treated as continuous and categorical. Specifically, upgrading occurred in 26% vs. 59% of patients with 50% or less vs. greater than 50% positive biopsies, respectively. This translated into a 5-year PSA failure-free survival which was significantly higher (92% vs. 62%, p = 0.00001) for men with 50% or less vs. greater than 50% positive prostate biopsies, respectively. CONCLUSION: The presence of greater than 50% positive biopsies was associated with higher rates of pathologic upgrading which translated into lower 5-year PSA failure-free survival following radical prostatectomy (RP). Therefore, the percentage of positive biopsies may be useful in optimizing the selection of low-risk patients for prostate only radiation therapy such as external beam radiation or implant monotherapy.

A clinical method for real-time dosimetric guidance of transperineal 125I prostate implants using interventional magnetic resonance imaging.

PURPOSE: The clinical utility of an interventional magnetic resonance (IMR)-guided implant technique with real-time dosimetric feedback is presented. METHODS AND MATERIALS: The work was carried out at a IMR unit at Brigham and Women's Hospital. Planning and dosimetric feedback were provided by a software system that provides an interface to the IMR images, anatomy demarcation, template registration, dose calculation engine for planning, and evaluating the implant. Planning during the procedure permits the incorporation of actual needle trajectories in the dose calculations. RESULTS: Fifteen patients were planned in the treatment position. During source placement, actual needle locations were incorporated into the dose calculations. After accounting for the observed needle trajectories of the planned needles, 14 of 15 patients (93%) required additional sources to achieve the desired coverage of the target volume. CONCLUSION: A brachytherapy implant procedure which provides clinically significant advances has been implemented. Specifically, the planning system allows dosimetric validation of the needle placement. This procedure is effective in delivering brachytherapy to the target volume and assuring that the implant is delivered in accordance with the preplan. The dosimetric feedback could be incorporated in ultrasound-guided implants.