Radiation dose escalation for localized prostate cancer

BACKGROUND:

In the current study, the effects of dose escalation for localized prostate cancer treatment with intensity‐modulated radiotherapy (IMRT) or permanent transperineal brachytherapy (BRT) in comparison with conventional dose 3‐dimensional conformal radiotherapy (3D‐CRT) were evaluated.

METHODS:

This study included 853 patients; 270 received conventional dose 3D‐CRT, 314 received high‐dose IMRT, 225 received BRT, and 44 received external beam radiotherapy (EBRT) + BRT boost. The median radiation doses were 68.4 grays (Gy) for 3D‐CRT and 75.6 Gy for IMRT. BRT patients received a prescribed dose of 144 Gy with iodine‐125 (I‐125) or 120 Gy with palladium‐103 (Pd‐103), respectively. Patients treated with EBRT + BRT received 45 Gy of EBRT plus a boost of 110 Gy with I‐125 or 90 Gy with Pd‐103. Risk group categories were low risk (T1‐T2 disease, prostate‐specific antigen level ≤10 ng/mL, and a Gleason score ≤6), intermediate risk (increase in value of 1 of the factors), and high risk (increase in value of ≥2 factors).

RESULTS:

With a median follow‐up of 58 months, the 5‐year biochemical control (bNED) rates were 74% for 3D‐CRT, 87% for IMRT, 94% for BRT, and 94% for EBRT + BRT (P <.0001). For the intermediate‐risk group, high‐dose IMRT, BRT, or EBRT + BRT achieved significantly better bNED rates than 3D‐CRT (P <.0001), whereas no improvement was noted for the low‐risk group (P = .22). There was no increase in gastrointestinal (GI) toxicity from high‐dose IMRT compared with conventional dose 3D‐CRT, although there was more grade 2 genitourinary (GU) toxicity (toxicities were graded at the time of each follow‐up visit using a modified Radiation Therapy Oncology Group [RTOG] scale). BRT caused more GU but less GI toxicity, whereas EBRT + BRT caused more late GU and GI toxicity than IMRT or 3D‐CRT.

CONCLUSIONS:

The data from the current study indicate that radiation dose escalation improved the bNED rate for the intermediate‐risk group. IMRT caused less acute and late GU toxicity than BRT or EBRT + BRT. Cancer 2009. © 2009 American Cancer Society.     

Long-term survival after radical prostatectomy versus external-beam radiotherapy for patients with high-risk prostate cancer

BACKGROUND:

The long‐term survival of patients with high‐risk prostate cancer was compared after radical prostatectomy (RRP) and after external beam radiation therapy (EBRT) with or without adjuvant androgen‐deprivation therapy (ADT).

METHODS:

In total, 1238 patients underwent RRP, and 609 patients received with EBRT (344 received EBRT plus ADT, and 265 received EBRT alone) between 1988 and 2004 who had a pretreatment prostate‐specific antigen (PSA) level ≥ 20 ng/mL, a biopsy Gleason score between 8 and 10, or clinical tumor classification ≥ T3. The median follow‐up was 10.2 years, 6.0 years, and 7.2 years after RRP, EBRT plus ADT, and EBRT alone, respectively. The impact of treatment modality on systemic progression, cancer‐specific survival, and overall survival was evaluated using multivariate Cox proportional hazard regression analysis and a competing risk‐regression model.

RESULTS:

The 10‐year cancer‐specific survival rate was 92%, 92%, and 88% after RRP, EBRT plus ADT, and EBRT alone, respectively (P = .06). After adjustment for case mix, no significant differences in the risks of systemic progression (hazard ratio [HR], 0.78; 95% confidence interval [CI], 0.51‐1.18; P = .23) or prostate cancer death (HR, 1.14; 95% CI, 0.68‐1.91; P = .61) were observed between patients who received EBRT plus ADT and patients who underwent RRP. The risk of all‐cause mortality, however, was greater after EBRT plus ADT than after RRP (HR, 1.60; 95% CI, 1.25‐2.05; P = .0002).

CONCLUSIONS:

RRP alone and EBRT plus ADT provided similar long‐term cancer control for patients with high‐risk prostate cancer. The authors concluded that continued investigation into the differing impact of treatments on quality‐of‐life and noncancer mortality will be necessary to determine the optimal management approach for these patients. Cancer 2011. © 2011 American Cancer Society.     

Population‐based 10‐year oncologic outcomes after low‐dose‐rate brachytherapy for low‐risk and intermediate‐risk prostate cancer

BACKGROUND.

The objective of this study was to report the rates of disease‐free survival (DFS), cause‐specific survival (CSS), and overall survival after low‐dose‐rate (LDR) prostate brachytherapy (PB).

METHODS.

Data from 1006 consecutive patients with prostate cancer who received LDR‐PB and underwent implantation on or before October 23, 2003 were extracted from a prospective database on November 11, 2011. The selected patients had low‐risk (58%) or intermediate‐risk (42%) disease according to National Comprehensive Cancer Network criteria. The Phoenix threshold was used to define biochemical relapse. Sixty‐five percent of patients received 3 months of neoadjuvant androgen‐deprivation therapy (ADT) and 3 months of concomitant ADT. Univariate and multivariate analyses are reported in relation to patient, tumor, and treatment variables.

RESULTS.

The median follow‐up was 7.5 years. By using Fine and Gray competing risks analysis, the 5‐year and 10‐year actuarial DFS rates were 96.7% (95% confidence interval, 95.2%‐97.7%) and 94.1% (95% confidence interval, 92%‐95.6%), respectively. When applied to the whole cohort, none of the usual prognostic variables, including dose metrics, were correlated with DFS. However, in both univariate and multivariate models, increasing dose was the only covariate that correlated with improved DFS for the subset of men (N = 348) who did not receive ADT (P = .043). The actuarial 10‐year CSS rate was 99.1% (95% confidence interval, 97.3%‐99.7%). The overall survival rate was 93.8% at 5 years (95% confidence interval, 92%‐95.1%) and 83.5% at 10 years (95% confidence interval, 79.8%‐86.6%). Only age at implantation (P = .0001) was correlated with overall survival in multivariate analysis.

CONCLUSIONS.

In a consecutive cohort of 1006 men with National Comprehensive Cancer Network low‐risk and intermediate‐risk prostate cancer, the actuarial rate of recurrent disease after LDR‐PB was approximately 3% at 5 years and 6% at 10 years. Cancer 2013. © 2012 American Cancer Society.     

Biochemical outcomes for patients with intermediate risk prostate cancer treated with I-125 interstitial brachytherapy monotherapy

Background and purpose

Routine use of I-125 interstitial brachytherapy (BT) alone in intermediate risk (IR) prostate cancer is controversial. It is often combined with external beam radiotherapy (EBRT). The biochemical outcome of a large cohort of only IR disease treated with BT monotherapy is reported.

Materials and methods

Between 2003 and 2007, 615 patients with Memorial Sloan-Kettering Cancer Centre (MSKCC) defined IR disease (one risk factor only-T2b, or Gleason score (GS) 7, or raised initial PSA (iPSA) 10.1–20 ng/ml) were treated with BT monotherapy. ASTRO (3 consecutive rises) and Phoenix (nadir plus 2) criteria defined biochemical failure. Potential prognostic factors (pre- and post-implant dosimetric indices, GS 3 + 4 versus 4 + 3, androgen deprivation therapy (ADT)) were analysed.

Results

Median follow-up was 5.0 years. Forty-three patients had stage T2b, 180 had raised iPSA, 392 had GS 7 disease. ADT was received by 108 patients. The 5-year biochemical no evidence of disease (bNED) rates are 87.3% (by ASTRO), 88.6% (by Phoenix). Stratification by risk factor (T2b, GS7, raised iPSA) demonstrated raised iPSA to have poorer outcome only by Phoenix criteria (p = 0.0002). Other potential prognostic variables were non-significant.

Conclusion

Good rates of biochemical control can be achieved in the medium term with BT monotherapy in IR disease. Raised iPSA correlated with a poorer outcome.     

Outcomes following iodine-125 prostate brachytherapy with or without neoadjuvant androgen deprivation

Purpose

To report the biochemical failure-free survival (BFFS), cause-specific survival (CSS), and overall survival (OS) outcomes of patients treated with iodine-125 (I-125) brachytherapy for clinically localized prostate cancer.

Methods and materials

Between 2003 and 2009, I-125 permanent prostate brachytherapy without supplemental external-beam radiotherapy was performed for 663 patients with low-risk and low-tier intermediate-risk (defined as organ-confined disease, PSA <10 ng/mL, and Gleason score 3 + 4 with biopsy positive core rate <33%) prostate cancer. Early in the study period, the preplanning method was used in the first 104 patients, and later the real-time planning method was used. Biochemical failure was determined using the American Society for Therapeutic Radiology Oncology (ASTRO) and Phoenix definitions.

Results

The 7-year BFFS rates for the ASTRO and Phoenix definitions were 96.1% and 95.9%, respectively. The corresponding BFFS rates by risk group were 97.6% and 96.7% for low-risk, and 91.8% and 93.6% for low-tier intermediate-risk disease (p = 0.007 and 0.08, respectively). The median times to biochemical failure in those who failed were 29.5 and 43.9 months according to the ASTRO and Phoenix definitions, respectively. The 7-year CSS and OS were 99.1% and 96.4%. There was no significant difference in CSS or OS between the low-risk and low-tier intermediate-risk groups. In multivariate Cox regression analysis, risk group and prostate D90 were independent predictors of BFFS for the ASTRO definition, while only the prostate D90 was significant for the Phoenix definition.

Conclusion

I-125 prostate brachytherapy results in excellent 7-year BFFS, CSS, and OS for low-risk and low-tier intermediate-risk prostate cancer.     

Results of high dose-rate brachytherapy boost before 2D or 3D external beam irradiation for prostate cancer

Background and purpose

To evaluate biochemical control and treatment related toxicity of patients with localized adenocarcinoma of the prostate treated with high dose-rate brachytherapy (HDRB) combined with conventional 2D or 3D-conformal external beam irradiation (EBI).

Material and methods

Four-hundred and three patients treated between December 2000 and March 2004. HDRB was delivered with three fractions of 5.5-7 Gy with a single implant, followed by 45 Gy delivered with 2D or 3D conformal EBI.

Results

The median follow-up was 48.4 months. Biochemical failure (BF) occurred in 9.6% according to both ASTRO and Phoenix consensus criteria. Mean time to relapse was 13 and 26 months, respectively. The 5-year BF free survival using the ASTRO criteria was 94.3%, 86.9% and 86.6% for the low, intermediate and high risk groups, respectively; using Phoenix criteria, 92.4%, 88.0% and 85.3%, respectively. The only predictive factor of BF in the multivariate analysis by both ASTRO and Phoenix criteria was the presence of prostate nodules detected by digital palpation, and patients younger than 60 years presented a higher chance of failure using Phoenix criteria only.

Conclusions

Treatment scheme is feasible and safe with good efficacy.     

Biochemical control of prostate cancer with iodine-125 brachytherapy alone: experience from a single institution

Aim  

Brachytherapy is an adequate option as monotherapy for localised prostate cancer. The objective of this study was to evaluate and compare biochemical failure free survival (BFFS) after low-dose-rate brachytherapy (LDRB) alone for patients with prostate cancer using ASTRO and Phoenix criteria, and detect prognostic factors.     

Impact of race on biochemical disease recurrence after prostate brachytherapy

BACKGROUND:

Understanding racial differences in disease presentation and response to therapy is necessary for the effective treatment and control of prostate cancer. In this study, the authors examined the influence of race on biochemical disease‐free survival (BDFS) among men who received prostate brachytherapy.

METHODS:

In total, 2301 men were identified who had a minimum follow‐up of 24 months and had received low‐dose‐rate brachytherapy for prostate cancer at the Mount Sinai Medical Center from June 1990 to October 2008. Patient factors, with specific emphasis on patient race, were analyzed with respect to freedom from biochemical failure (FFbF). Kaplan‐Meier analyses, life‐tables, and log‐rank tests were used to identify variables that were predictive of 10‐year FFbF.

RESULTS:

In this series, a total of 2268 patients included 81% Caucasians, 12% African Americans, 6% Hispanics, and 1% Asians. The 10‐year actuarial FFbF rate was 70% for AA men and 84% for all others (P = .002). Between Caucasian men and AA men, the 10‐year FFbF rate was 83% versus 70%, respectively (P = .001).There was no significant difference in 10‐year FFbF between Caucasian men and Hispanic men (83% vs 86%, respectively; P = .6). The 10‐year FFbF rate for Hispanic men and AA men was 86% versus 70%, respectively (P = .062). A greater percentage of AA men presented with higher prostate‐specific antigen levels (PSA) (>10 ng/mL; 44% vs 21%; P < .001) and, thus, with higher risk disease (24% vs 15%; P < .001) compared with Caucasian men. Among the men with low‐risk disease, the 10‐year FFbF rate was 90% for Caucasian men and 76% for AA men (P = .041). The 10‐year BDFS rate for patients who received brachytherapy alone was 86% for Caucasian men and 61% for AA men (P = .001); however, this difference was not observed when brachytherapy was combined with androgen‐deprivation therapy(ADT) with or without supplemental external‐beam radiotherapy (EBRT). Multivariate analysis revealed that PSA (P = .024), Gleason score (P < .001), the biologic effective dose (P < .001), EBRT (P = .002), ADT (P = .03), and AA race (P = .037) were significant predictors of 10‐year FFbF. No significant differences was observed in overall survival, cause‐specific survival, or distant metastasis‐free survival between racial groups.

CONCLUSIONS:

AA race appeared to be an independent negative predictor of BDFS after prostate brachytherapy, and this result may highlight the need for more aggressive therapy in this patient population. Cancer 2011;. © 2011 American Cancer Society.     

Interval to biochemical failure as a biomarker for cause-specific and overall survival after dose-escalated external beam radiation therapy for prostate cancer

BACKGROUND:

After external beam radiation therapy (EBRT) for prostate cancer, a short interval to biochemical failure of <18 months has been proposed as a surrogate for cause‐specific survival. Because EBRT dose influences biochemical failure, the authors investigated the interval to biochemical failure in a cohort of patients treated with dose‐escalated EBRT.

METHODS:

From 1998 to 2008, 710 patients were treated with EBRT (≥75 grays) ± androgen deprivation therapy (ADT) at the University of Michigan. Biochemical failure was defined using the Phoenix consensus definition (nadir + 2 ng/mL). A short interval to biochemical failure was defined as <18 months after completing radiotherapy and/or ADT. The associations between biochemical failure, the interval to biochemical failure, and clinical factors with cause‐specific survival (CSS) and overall survival (OS) were evaluated.

RESULTS:

There were 149 biochemical failures (21%), and short interval to biochemical failure accounted for 14% and 40% of biochemical failures in those with intermediate‐risk or high‐risk disease, respectively. Biochemical failure impacted CSS (P < .0001) but not OS (P = .36). However, a short interval to biochemical failure predicted decreased CSS (P < .0001; hazard ratio [HR], 5.6; 95% confidence interval [CI], 2.4‐13.0) and OS (P < .0001; HR, 4.8; 95% CI, 2.3‐10.3) when compared with a long interval to biochemical failure. The 8‐year OS was 78% without biochemical failure, compared with 87% with a long interval to biochemical failure (P = .1; HR, 0.7; 95% CI, 0.4‐1.1) and 38% with a short interval to biochemical failure (P < .0001; HR, 3.7; 95% CI, 2.3‐5.9). On multivariate analysis, a short interval to biochemical failure increased the risk of prostate cancer death (P < .0001; HR, 18.1; 95% CI, 8.4‐39) and all cause mortality (P = .0027; HR, 1.5; 95% CI, 1.2‐2.1), whereas a long interval to biochemical failure did not.

CONCLUSIONS:

The relation between the interval to biochemical failure, CSS, and OS was independently validated in patients treated with dose‐escalated EBRT. Further evaluation of the interval to biochemical failure as a surrogate endpoint is warranted. Cancer 2012. © 2011 American Cancer Society.     

External beam radiotherapy plus single-fraction high dose rate brachytherapy in the treatment of locally advanced prostate cancer

Purpose

To evaluate the efficacy and toxicity of external beam radiation therapy (EBRT) plus high-dose-rate brachytherapy (HDRB) as a boost in patients (pts) with intermediate or high-risk prostate cancer.

Methods and materials

From 2002 to July 2012, 377 pts with a diagnosis of intermediate or high-risk prostate cancer were treated with EBRT plus HDRB. Median patient age was 66 years (range, 41–86). Most patients (347 pts; 92%) were classified as high-risk (stage T2c–T3, or PSA > 20 ng/mL, or GS ? 8), with 30 patients (8%) considered intermediate risk. All patients underwent EBRT at a prescribed dose of 60.0 Gy (range, 45–70 Gy) to the prostate and seminal vesicles. A total of 120 pts (31%) received a dose of 46 Gy (45–50 Gy) to the true pelvis. All pts received a single-fraction 9 Gy (9–15 Gy) HDR boost. Most patients (353; 94%) were prescribed complete androgen deprivation therapy (ADT). Overall survival (OS), cause-specific survival (CSS), and biochemical relapse-free survival (BRFS) rates were calculated. In the case of BRFS, patients with <26 months of follow-up (n = 106) were excluded to minimize the impact of ADT.

Results

The median follow-up for the entire sample was 50 months (range, 12–126), with 5-year actuarial OS and CSS, respectively, of 88% (95% confidence interval [CI]: 84–92) and 98% (95% CI: 97–99). The 5-year BRFS was 91% (95% CI: 87–95) in the 271 pts with ?26 months (median, 60 months) of follow-up. Late toxicity included grade 2 and 3 gastrointestinal toxicity in 17 (4.6%) and 6 pts (1.6%), respectively, as well as grades 2 and 3 genitourinary toxicity in 46 (12.2%) and 3 pts (0.8%), respectively.

Conclusion

These long-term outcomes confirm that EBRT plus a single-fraction HDRB boost provides good results in treatment-related toxicity and biochemical control. In addition to the excellent clinical results, this fractionation schedule reduces physician workload, treatment-related expenses, patient discomfort and risks associated with anaesthesia. We believe these findings support the use of single-fractionation boost techniques.     

Five-year biochemical outcome following permanent interstitial brachytherapy for clinical T1-T3 prostate cancer

PURPOSE: To evaluate 5-year biochemical disease-free outcome for men with clinical T1b-T3a NxM0 1977 American Joint Committee on Cancer (1997 AJCC) adenocarcinoma of the prostate gland who underwent transperineal ultrasound-guided permanent prostate brachytherapy. METHODS AND MATERIALS: Four hundred twenty-five patients underwent transperineal ultrasound-guided prostate brachytherapy using either 103Pd or 125I, for clinical T1b-T3a NxM0 (1997 AJCC) adenocarcinoma of the prostate gland, from April 1995 to October 1999. No patient underwent pathologic lymph-node staging. One hundred ninety patients were implanted with either 103Pd or 125I monotherapy; 235 patients received moderate-dose external beam radiation therapy (EBRT), followed by a prostate brachytherapy boost; 163 patients received neoadjuvant hormonal manipulation, in conjunction with either 103Pd or 125I monotherapy (77 patients) or in conjunction with moderate-dose EBRT and a prostate brachytherapy boost (86 patients). The median patient age was 68.0 years (range, 48.2-81.3 years). The median follow-up was 31 months (range, 11-69 months). Follow-up was calculated from the day of implantation. No patient was lost to follow-up. Biochemical disease-free survival was defined by the American Society of Therapeutic Radiation and Oncology (ASTRO) consensus definition. RESULTS: For the entire cohort, the 5-year actuarial biochemical no evidence of disease (bNED) survival rate was 94%. For patients with low-, intermediate-, and high-risk disease, the 5-year biochemical disease-free rates were 97.1%, 97.5%, and 84.4%, respectively. For hormone-naive patients, 95.7%, 96.4%, and 79.9% of patients with low-, intermediate-, and high-risk disease were free of biochemical failure. Clinical and treatment parameters predictive of biochemical outcome included: clinical stage, pretreatment prostate-specific antigen (PSA), Gleason score, risk group, age > 65 years, and neoadjuvant hormonal therapy. Isotope choice was not a statistically significant predictor of disease-free survival for any risk group. The median postimplant PSA was < or = 0.2 for all risk groups, regardless of hormonal status. The mean posttreatment PSA, however, was significantly lower for men implanted with 103Pd (0.14 ng/mL) than for those implanted with 125I (0.25 ng/mL), p < or = 0.001. CONCLUSION: With a median follow-up of 31 months, permanent prostate brachytherapy results in a high probability of actuarial 5-year biochemical disease-free survival (DFS) for patients with clinical T1b-T3a (1997 AJCC) adenocarcinoma of the prostate gland, with an apparent plateau on the PSA survival curve.     

Evaluation of clinical and endoscopic toxicity after external beam radiotherapy and endorectal brachytherapy in elderly patients with rectal cancer treated in the HERBERT study

Introduction

The HERBERT study evaluated a high-dose-rate endorectal brachytherapy boost (HDREBT) after EBRT in medically inoperable/elderly patients with rectal cancer. The response-rates are promising but not without risk of toxicity. The current analysis provides a comprehensive overview of patient reported, physician reported and endoscopically observed toxicity.

Is single fraction 15 Gy the preferred high dose-rate brachytherapy boost dose for prostate cancer?

Background and purpose

High dose-rate (HDR) brachytherapy is most commonly administered as a boost in two or more fractions combined with external beam radiotherapy (EBRT). Our purpose is to compare outcomes with a single fraction HDR boost to that with a standard fractionated boost in intermediate risk prostate cancer.

Materials and methods

Results of two sequential phase II clinical trials are compared. The Single Fraction protocol consists of 15 Gy HDR in one fraction followed by 37.5 Gy EBRT in 15 fractions over 3 weeks; the Standard Fractionation protocol consisted of two HDR fractions each of 10 Gy, 1 week apart, followed by 45 Gy EBRT in 25 fractions. Patients had intermediate risk disease, and were well balanced for prognostic factors. Patients were followed prospectively for efficacy, toxicity and health-related quality of life (Expanded Prostate Index Composite). Efficacy was assessed biochemically using the Phoenix definition, and by biopsy at 2 years.

Results

The Single Fraction protocol accrued 123 patients and the Standard Fractionation protocol, 60. With a median follow-up of 45 and 72 months, respectively, the biochemical disease-free survival was 95.1% and 97.9% in the Single and Standard Fractionation trials (p = 0.3528). Two-year prostate biopsy was positive in only 4% and 8%, respectively. There was no difference in late urinary or rectal toxicity rates, or in health-related quality of life between the two protocols.

Conclusions

The Single Fraction HDR protocol results in high disease control rate and low toxicity similar to our previous protocol using two HDR insertions, with significant savings in resources. While mature results with longer follow-up are awaited, a single 15 Gy may be considered as a standard fractionation regimen in combination with EBRT for men with intermediate risk disease.     

The impact of dose‐escalated radiotherapy plus androgen deprivation for prostate cancer using 2 linked nomograms

BACKGROUND:

Randomized trials have demonstrated that escalated‐dose external‐beam radiotherapy (EDRT) is better than standard‐dose radiotherapy (SDRT) for patients with prostate cancer and that adding androgen‐deprivation therapy (ADT) to SDRT is better than SDRT alone; however, no trials have compared EDRT versus SDRT plus ADT or EDRT versus EDRT plus ADT. The authors designed a model to estimate the results of various doses of radiotherapy (RT) combined with various durations of ADT.

METHODS:

From 1989 to 2007, 3215 men consecutively received definitive EDRT with or without ADT. In total, 2012 patients had complete records available for creating the nomogram. The duration of ADT varied for patients who received no RT (n = 1562), ≤6 months of RT (n = 145), from >6 months to <24 months of RT (n = 140), and ≥24 months of RT (n = 165) with a median follow‐up of 65.7 months, 66.2 months, 60.1 months, and 63 months, respectively. The model included the following covariates: palpation T‐category, biopsy Gleason score, the percentage of tumor cells with a Gleason pattern of 4 or 5, the percentage of tumor tissue, initial pretreatment prostate‐specific antigen (PSA) level, ADT duration, and RT dose. Two nomograms, for outcomes with and without ADT, were created from a single competing‐risks model. Biochemical failure was defined as a rise in serum PSA of 2 ng/mL over the post‐treatment PSA nadir.

RESULTS:

According to the results from analyzing representative intermediate‐risk to high‐risk patient parameters, the gains from increasing the RT dose from 70 Gray (Gy) to 80 Gy were far less than the gains from adding ≥3 months of ADT.

CONCLUSIONS:

The nomograms provided unique patient‐specific estimates of the effects of various doses and durations of RT and ADT. The results indicated that adding ADT to treatment for intermediate‐risk and high‐risk prostate cancer is far more beneficial than a modest RT dose escalation. Cancer 2013. © 2012 American Cancer Society.     

Dose‐escalated radiation therapy for intermediate‐risk prostate cancer

BACKGROUND:

Randomized trials supported the use of androgen deprivation therapy (ADT) with radiation therapy (RT) for intermediate‐risk prostate cancer. However, the value of concurrent ADT was less certain with dose‐escalated RT. Better methods of stratifying patients in this risk group may help select patients who are most likely to benefit.

METHODS:

A total of 238 men with intermediate‐risk (prostate specific antigen [PSA] 10‐20, Gleason 7, or stage T2b‐c) adenocarcinoma of the prostate were treated with external beam RT between 1989 and 2006. Patients had Gleason≤6 (39%) or 7 (61%) tumors; median PSA was 10.5 ng/mL. A median of 37.5% of biopsy cores were positive from a median of 9 biopsy cores sampled. The median RT dose was 74 Gy to the prostate. A total of 112 patients (47%) received neoadjuvant and concurrent ADT (median, 4 months). Median follow‐up period was 49 months.

RESULTS:

The freedom from biochemical failure (FFBF, nadir + 2 definition) was 93% at 3 years, 86% at 4 years, and 80% at 5 years. On univariate analysis, the only factor associated with FFBF was percentage of positive cores (PPC, P = .0340). The prognostic value of PPC≥50 was not evident in patients receiving ADT (FFBF at 4 years 90% vs 91%, P = .3015). For patients not receiving ADT, the impact of PPC≥50 (FFBF at 4 years 76% vs 93%, P = .0844) was more pronounced. On multivariate analysis, PPC (P = .0388) was significantly associated with FFBF, whereas Gleason sum, ADT, RT dose, PSA, and T‐stage were not.

CONCLUSIONS:

After dose‐escalated external beam RT, intermediate‐risk prostate cancer patients with PPC≥50 had the highest risk for biochemical failure and may be most likely to derive a benefit from ADT. Cancer 2009. © 2009 American Cancer Society.     

Androgen deprivation and thromboembolic events in men with prostate cancer

BACKGROUND:

Androgen deprivation therapy (ADT) improves prostate cancer outcomes in specific clinical settings, but is associated with adverse effects, including cardiac complications and possibly thromboembolic complications. The objective of this study was to estimate the impact of ADT on thromboembolic events (TEs) in a population‐based cohort.

METHODS:

In the linked Surveillance, Epidemiology and End Results–Medicare database, we identified men older than 65 who were diagnosed with nonmetastatic prostate cancer between 1999 and 2005. Medical or surgical ADT was identified by Medicare claims for gonadotropin‐releasing hormone agonists or bilateral orchiectomy at any time following diagnosis. TEs included deep venous thrombosis, pulmonary embolism, and arterial embolism. The impact of ADT on the risk of any TE and on total number of events was estimated, controlling for patient and tumor characteristics.

RESULTS:

Of 154,611 patients with prostate cancer, 58,466 (38%) received ADT. During a median follow‐up of 52 months, 15,950 men had at least 1 TE, including 8829 (55%) who had ADT and 7121 (45%) with no ADT. ADT was associated with increased risk of a TE (adjusted hazard ratio = 1.56; 95% confidence interval, 1.50‐1.61; P < .0001), and duration of ADT was associated with the total number of events (P < .0001).

CONCLUSIONS:

In this population‐based cohort, ADT was associated with increased risk of a TE, and longer durations of ADT were associated with more TEs. Men with intermediate‐ and low‐risk prostate cancer should be assessed for TE risk factors before starting ADT and counseled regarding the risks and benefits of this therapy. Cancer 2011. © 2011 American Cancer Society.     

Short-Course External Beam Radiotherapy Versus Brachytherapy for Palliation of Dysphagia in Esophageal Cancer: A Matched Comparison of Two Prospective Trials

IntroductionShort-course external beam radiotherapy (EBRT) and intraluminal brachytherapy are both accepted treatments for the palliation of dysphagia in patients with incurable esophageal cancer. We compared the effects of both treatments from two prospective studies.MethodsWe performed a multicenter prospective cohort study of patients with metastasized or otherwise incurable esophageal cancer requiring palliation of dysphagia from September 2016 to March 2019. Patients were treated with EBRT in five fractions of 4 Gy. Data were compared with all patients treated with a single brachytherapy dose of 12 Gy in the SIREC (Stent or Intraluminal Radiotherapy for inoperable Esophageal Cancer) trial, both between the original cohorts and between 1:1 propensity score–matched cohorts. The primary end point was an improvement of dysphagia at 3 months without reintervention. The secondary end points included toxicity and time-to-effect.ResultsA total of 115 patients treated with EBRT and 93 patients who underwent brachytherapy were eligible for analysis. In the original cohorts, dysphagia improved after EBRT in 79% of patients compared with 64% after brachytherapy (p = 0.058). Propensity score matching resulted in 69 patients in each cohort well-balanced at baseline. Improvement of dysphagia was observed in 83% after EBRT versus 64% after brachytherapy (p = 0.048). In responding patients, improvement of dysphagia at 2 weeks was observed in 67% after EBRT compared with 35% after brachytherapy, and the maximum effect was reached after 4 weeks in 55% and 33%, respectively. Severe toxicity occurred in 3% of patients after EBRT compared with 13% after brachytherapy.ConclusionsShort-course EBRT appears at least as effective as brachytherapy in the palliation of dysphagia in patients with esophageal cancer.     

Matched-pair analysis of conformal high-dose-rate brachytherapy boost versus external-beam radiation therapy alone for locally advanced prostate cancer.

PURPOSE: We performed a matched-pair analysis to compare our institution's experience in treating locally advanced prostate cancer with external-beam radiation therapy (EBRT) alone to EBRT in combination with conformal interstitial high-dose-rate (HDR) brachytherapy boosts (EBRT + HDR). MATERIALS AND METHODS: From 1991 to 1998, 161 patients with locally advanced prostate cancer were prospectively treated with EBRT + HDR at William Beaumont Hospital, Royal Oak, Michigan. Patients with any of the following characteristics were eligible for study entry: pretreatment prostate-specific antigen (PSA) level of >/= 10.0 ng/mL, Gleason score >/= 7, or clinical stage T2b to T3c. Pelvic EBRT (46.0 Gy) was supplemented with three (1991 through 1995) or two (1995 through 1998) ultrasound-guided transperineal interstitial iridium-192 HDR implants. The brachytherapy dose was escalated from 5.50 to 10.50 Gy per implant. Each of the 161 EBRT + HDR patients was randomly matched with a unique EBRT-alone patient. Patients were matched according to PSA level, Gleason score, T stage, and follow-up duration. The median PSA follow-up was 2.5 years for both EBRT + HDR and EBRT alone. RESULTS: EBRT + HDR patients demonstrated significantly lower PSA nadir levels (median, 0.4 ng/mL) compared with those receiving EBRT alone (median, 1.1 ng/mL). The 5-year biochemical control rates for EBRT + HDR versus EBRT-alone patients were 67% versus 44%, respectively (P <.001). On multivariate analyses, pretreatment PSA, Gleason score, T stage, and the use of EBRT alone were significantly associated with biochemical failure. Those patients in both treatment groups who experienced biochemical failure had a lower 5-year cause-specific survival rate than patients who were biochemically controlled (84% v 100%; P <.001). CONCLUSION: Locally advanced prostate cancer patients treated with EBRT + HDR demonstrate improved biochemical control compared with those who are treated with conventional doses of EBRT alone.