Results of 3D conformal radiotherapy in the treatment of localized prostate cancer

Current Status of Salvage Cryoablation for Prostate Cancer following Radiation Failure

The role of salvage cryoablation of the prostate for patients with clinically localized prostate cancer that have failed radiotherapy to the prostate is reviewed with reference to alternatives including salvage radical prostatectomy and brachytherapy. The diagnosis and work-up of local recurrence/persistence of cancer in the prostate are reviewed and the patient selection criteria for salvage cryoablation is discussed. Technical aspects of the cryoablation procedure along with the outcome in terms of cancer control and treatment-related complications are detailed. The five-year biochemical disease-free rate is approximately 40%. The complication rate is acceptable. Salvage cryoablation definitely has a role in the management of localized prostate cancer treatment failure following radiotherapy, especially in older patients and those with some comorbidities.

Testosterone Therapy after Radiation Therapy for Low, Intermediate and High Risk Prostate Cancer

PURPOSE

Limited literature exists regarding the safety of testosterone therapy in men treated for prostate cancer. We present multi-institutional data on testosterone therapy in hypogonadal men with prostate cancer treated with radiation therapy.

MATERIALS AND METHODS

We retrospectively reviewed the records of hypogonadal men treated with testosterone therapy after radiation therapy for prostate cancer at 4 institutions. Serum testosterone, free testosterone, estradiol, sex hormone-binding globulin, prostate specific antigen, prostate specific antigen velocity and prostate biopsy findings were analyzed.

RESULTS

A total of 98 men were treated with radiation therapy. Median age was 70.0 years (range 63.0 to 74.3) at initiation of testosterone therapy. Median baseline testosterone was 209 ng/dl (range 152 to 263) and median baseline prostate specific antigen was 0.08 ng/ml (range 0.00 to 0.33). In the cohort the tumor Gleason score was 5 in 3 men (3.1%), 6 in 44 (44.9%), 7 in 28 (28.6%), 8 in 7 (7.1%) and 9 in 4 (4.1%). Median followup was 40.8 months (range 1.5 to 147). Serum testosterone increased to a median of 420 ng/dl (range 231 to 711) during followup (p <0.001). Overall a nonsignificant increase in mean prostate specific antigen was observed from 0.08 ng/ml at baseline to 0.09 ng/ml (p = 0.05). Among patients at high risk prostate specific antigen increased from 0.10 to 0.36 ng/ml (p = 0.018). Six men (6.1%) met criteria for biochemical recurrence.

CONCLUSIONS

Testosterone therapy in men following radiation therapy for prostate cancer was associated with a minor increase in serum prostate specific antigen and a low rate of biochemical recurrence.

Brachytherapy for the treatment of recurrent prostate cancer after radiotherapy or radical prostatectomy

What's known on the subject? and What does the study add? The curative treatment of prostate cancer includes surgery, external beam radiation or interstitial radiation. However, a high percentage of patients may develop recurrent disease, which is often localised. The possibilities of treatment in these cases, including surgery or adjuvant radiotherapy, are not well defined. Brachytherapy is a well established first-line treatment option. We review and update the use of brachytherapy in the treatment of recurrences post-radiotherapy, brachytherapy or radical prostatectomy as an alternative to surgery and radiotherapy, with a focus on functional and oncological outcomes. Salvage therapeutic options following radical prostatectomy or radiotherapy for patients with local relapse of prostate cancer include radical prostatectomy, radiotherapy, brachytherapy or cryotherapy. Salvage radical prostatectomy following radiotherapy failure is associated with a 5-year PSA relapse-free rate of 30-40%. Biochemical relapse-free survival rates after salvage radiotherapy following radical prostatectomy failure range from 10% to 77% after a follow-up of 22-60 months. A number of studies have evaluated salvage brachytherapy for radiotherapy failure and 5-year biochemical disease-free survival (bDFS) rate results reported are of the order of 20-87%; one study reported a 10-year bDFS rate of 54%. Fewer studies in small numbers of patients and with shorter follow-up have been conducted on brachytherapy for radical prostatectomy failure and bDFS rates reported include 25.8% at a median of 29 months to 70% at a median of 20 months. The side-effects were as expected for brachytherapy. A newer initiative conducted in Spain in a larger series of 42 patients with failure following radical prostatectomy involves brachytherapy with RAPID Strand™(125) I seeds and real-time placement. The 5-year bDFS rate was 88.6% and cancer-specific survival was 97%; complication rates were low. Optimization of salvage brachytherapy is under way and involves accurate placement of seeds, dose optimization and optimal patient selection.

A novel correction factor based on extended volume to complement the conformity index

OBJECTIVE

We propose a modified conformity index (MCI), based on extended volume, that improves on existing indices by correcting for the insensitivity of previous conformity indices to reference dose shape to assess the quality of high-precision radiation therapy and present an evaluation of its application.

METHODS

In this paper, the MCI is similar to the conformity index suggested by Paddick (CI(Paddick)), but with a different correction factor. It is shown for three cases: with an extended target volume, with an extended reference dose volume and without an extended volume. Extended volume is generated by expanding the original volume by 0.1-1.1 cm isotropically. Focusing on the simulation model, measurements of MCI employ a sphere target and three types of reference doses: a sphere, an ellipsoid and a cube. We can constrain the potential advantage of the new index by comparing MCI with CI(Paddick). The measurements of MCI in head-neck cancers treated with intensity-modulated radiation therapy and volumetric-modulated arc therapy provide a window on its clinical practice.

RESULTS

The results of MCI for a simulation model and clinical practice are presented and the measurements are corrected for limited spatial resolution. The three types of MCI agree with each other, and comparisons between the MCI and CI(Paddick) are also provided.

CONCLUSION

The results from our analysis show that the proposed MCI can provide more objective and accurate conformity measurement for high-precision radiation therapy. In combination with a dose-volume histogram, it will be a more useful conformity index.

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.

Correlates of bother following treatment for clinically localized prostate cancer

PURPOSE

We determined factors associated with bother, the distress patients experience as a result of functional detriments after treatment for localized prostate cancer.

MATERIALS AND METHODS

A prospective cohort of men treated for clinically localized prostate cancer completed a questionnaire comprising the UCLA-PCI, Medical Outcomes Study Short Form-36, American Urological Association Symptom Index and Memorial Anxiety Scale for Prostate Cancer fear of recurrence subscale. We used nonlinear mixed models to identify factors associated with severe urinary, sexual and bowel bother.

RESULTS

Worse function scores were associated with severe urinary, sexual and bowel bother following treatment (OR 0.88-0.94, p <0.001). Worse American Urological Association Symptom Index score was associated with severe urinary bother (OR 1.22, 95% CI 1.16-1.28). Time since treatment was inversely associated with urinary (OR 0.68, 95% CI 0.54-0.83) and bowel bother (OR 0.63, 95% CI 0.47-0.80) early after treatment but not for the entire 48-month study period. Receipt of concomitant androgen deprivation therapy was not associated with bother 48 months after radiation.

CONCLUSIONS

Addressing functional detriment may confer improvement in urinary, sexual and bowel bother. Patient distress related to dysfunction improves with time. Measuring health related quality of life after prostate cancer treatment should incorporate functional and bother assessments.

Neoadjuvant androgen deprivation for prostate volume reduction: the optimal duration in prostate cancer radiotherapy

OBJECTIVES

For locally advanced prostate cancer, the results of radiotherapy are improved by combination with androgen deprivation therapy. Volume reduction achieved with neoadjuvant hormonal treatment can facilitate dose escalation without increasing the toxicity. The optimal duration of hormonal treatment, however, is unknown. The endpoint of this study is the optimal duration of androgen deprivation for prostate volume reduction in a cohort of patients scheduled for external beam radiotherapy.

PATIENTS AND METHODS

Twenty patients scheduled for external beam radiotherapy with cT2-3No/xMo prostate cancer were treated with a luteinizing hormone releasing hormone agonist (busereline) and nonsteroidal anti-androgen (nilutamide) for 9 months consecutively. Repeated CT scan examination was performed 3-monthly to measure prostate volumes until the start of radiation therapy. The analysis of volume reduction was performed with the Wilcoxon signed ranks test.

RESULTS

The baseline median prostate volume for the cohort of patients was 82 cc (95% CI: 61-104 cc) with a median volume reduction of 31% (95% CI: 26%-35%) (P < 0.0001) after 3 months of androgen deprivation. Between 3 and 6 months, a median volume reduction of 9% (95% CI: 4%-14%) (P < 0.0001) was observed. The effect was more pronounced in large prostates (>60 cc) than in small prostates (≤60 cc). In the total cohort of patients no significant volume reduction occurred between 6 and 9 months of maximal androgen blockade (MAB).

CONCLUSIONS

In this study, we have shown that the most significant prostate volume reduction is achieved after 3 months of MAB with a maximum reduction after 6 months. Therefore, the optimal duration of neoadjuvant androgen deprivation to reduce prostate volume before prostate cancer radiotherapy is 6 months. In small prostates 3 months of hormonal treatment may be enough for maximal volume reduction.

Quality of life after surgery, external beam irradiation, or brachytherapy for early-stage prostate cancer

BACKGROUND

The primary treatments for clinically localized prostate cancer confer equivalent cancer control for most patients but disparate side effects. In the current study, the authors sought to compare health-related quality of life (HRQOL) outcomes after the most commonly used treatments.

METHODS

A total of 580 men completed the Medical Outcomes Study Short Form-36, the University of California-Los Angeles (UCLA) Prostate Cancer Index, and the American Urological Association Symptom Index before and through 24 months after treatment with radical prostatectomy (RP), external beam radiation therapy (EBRT), or brachytherapy (BT).

RESULTS

General HRQOL did not appear to be affected by treatment. Obstructive and irritative urinary symptoms were more common after BT (P<.001). Urinary control and sexual function were better after EBRT than BT (P<.001 and P=.02, respectively) and better after BT than RP (P<.001 and P=.01, respectively). Among potent men, recovery of sexual function was best after EBRT and was equivalent after bilateral nerve-sparing surgery or BT. Sexual bother was more common than urinary or bowel bother after all 3 treatments. Bowel dysfunction was more common after EBRT or BT than RP (P<.001).

CONCLUSIONS

In the current study, treatment for localized prostate cancer was found to differentially affect HRQOL outcomes. Urinary control and sexual function were better after EBRT, although bilateral nerve-sparing surgery diminished these differences among potent men undergoing RP. BT caused more obstructive and irritative symptoms, while both forms of radiation caused more bowel dysfunction. These results may inform medical decision-making in men with localized prostate cancer.

Estimating the risk of long-term erectile, urinary and bowel symptoms resulting from prostate cancer treatment

Reports on long-term complications resulting from treatment for localized prostate cancer are very inconsistent. In order to estimate the risks of long-term erectile dysfunction, urine symptoms and bowel symptoms following prostatectomy (RP), external conventional or conformal beam radiation (ERT or CRT) and brachytherapy (BRT), 98 papers from the PubMed and Cochrane Clinical Trial databases were selected, reviewed and critically evaluated. The majority of papers were institution-based retrospective and prospective follow-up studies; only two of these studies measured the risk of developing more than one treatment complication. Due to differences in study designs and populations, it is difficult to directly compare studies and not meaningful to calculate summary estimates. In addition to focusing on randomized clinical trials and well-designed population based studies, future research should adopt standardized methodologies and should measure the risk of developing more than one treatment complication.

Evidence-based review of three-dimensional conformal radiotherapy for localized prostate cancer: An ASTRO outcomes initiative

PURPOSE

To perform a systematic review of the evidence to determine the efficacy and effectiveness of three-dimensional conformal radiotherapy (3D-CRT) for localized prostate cancer; provide a clear presentation of the key clinical outcome questions related to the use of 3D-CRT in the treatment of localized prostate cancer that may be answered by a formal literature review; and provide concise information on whether 3D-CRT improves the clinical outcomes in the treatment of localized prostate cancer compared with conventional RT.

METHODS AND MATERIALS

We performed a systematic review of the literature through a structured process developed by the American Society for Therapeutic Radiology and Oncology's Outcomes Committee that involved the creation of a multidisciplinary task force, development of clinical outcome questions, a formal literature review and data abstraction, data review, and outside peer review.

RESULTS

Seven key clinical questions were identified. The results and task force conclusions of the literature review for each question are reported.

CONCLUSION

The technological goals of reducing morbidity with 3D-CRT have been achieved. Randomized trials and follow-up of completed trials remain necessary to address these clinical outcomes specifically with regard to patient subsets and the use of hormonal therapy.

Comparison of external radiation therapy vs radical prostatectomy in lymph node positive prostate cancer patients

INTRODUCTION

Treatment options for lymph node positive prostate cancer are limited. We retrospectively compared patients who underwent external radiotherapy (ERT) to patients treated by radical prostatectomy (RPX).

MATERIALS AND METHODS

A total of 102 lymph node positive patients from the RPX series at Ulm University were evaluated. In all, 76 patients received adjuvant androgen withdrawal as part of their primary treatment. In the ERT group, 44 patients were treated at the University of Michigan using a fractionated regimen. Of these, 21 patients received early adjuvant hormonal therapy. Patients with neoadjuvant therapy before RPX or ERT were excluded.

RESULTS

In the RPX group, PSA nadir (nadir < or = 0.2 vs > 0.2 ng/ml) showed a strong association with outcome. In the ERT group, pretreatment PSA was an independent predictor of outcome (P = 0.04) and patients with adjuvant hormonal therapy had a significant longer recurrence-free interval compared to patients without adjuvant therapy (P = 0.004). Comparing only patients with adjuvant hormonal treatment after cancer-specific therapy, the ERT-treated patients had a borderline longer PSA recurrence-free survival time compared to the RPX-treated patients (P = 0.05).

CONCLUSIONS

In case of positive lymph nodes, RPX and ERT might be considered and need to be explained to the patient. For future treatment decisions, the presented findings and a potential survival benefit need to be evaluated in a larger prospective setting.

CURRENT STATUS OF LOCAL SALVAGE THERAPIES FOLLOWING RADIATION FAILURE FOR PROSTATE CANCER

PURPOSE

We reviewed the curative options available to patients with local failure after radical radiotherapy for prostate cancer and identified the patients best suited for such salvage therapies.

MATERIALS AND METHODS

A literature search of English language publications was done using the key terms salvage, prostatectomy, cryosurgery, brachytherapy and radiation failure.

RESULTS

Salvage radical prostatectomy offers 5-year biochemical relapse-free rates between 55 and 69%. Higher complication rates are reported with salvage compared to primary radical prostatectomy, including rectal injuries, bladder neck contracture and urinary incontinence. Cryosurgery biochemical response rates vary according to the definition of failure but they are generally lower than those of salvage radical prostatectomy. The local control rates of cryosurgery are acceptable. Major complications related to cryotherapy are urinary incontinence, impotence, pelvic pain and urinary retention. Experience with salvage brachytherapy has been limited but some success has been reported in terms of biochemical control.

CONCLUSIONS

Salvage prostatectomy for localized radiation failure is a good option in the patient with a life expectancy of at least 10 years, preradiation and preoperative prostate specific antigen less than 10 ng/ml, and localized preoperative stage with the understanding that complication risks are higher. Salvage cryotherapy is a valid option in patients with preoperative prostate specific antigen less than 10 ng/ml and Gleason score less than 8, clinical stage less than T3 who are hormonally naive. Salvage cryotherapy is especially suited for older patients with some comorbidities who are still considered to be at reasonable anesthetic risk. The study of brachytherapy remains in its infancy and the efficacy of this modality remains to be determined.

Combined external beam radiotherapy and Pd-103 brachytherapy boost improves biochemical failure free survival in patients with clinically localized prostate cancer: results of a matched pair analysis

BACKGROUND

Dose escalation has resulted in improved biochemical control in patients with clinically localized prostate cancer treated with conformal external beam radiation (EBRT). Conformal dose distributions may also be achieved with brachytherapy. Therefore, biochemical control was evaluated for patients treated with combined external radiation therapy and low dose rate brachytherapy (EBRT + LDR).

METHODS

A matched pair analysis was performed to compare biochemical control of patients treated with EBRT + LDR to patients treated with EBRT alone. The study endpoints were biochemical control and late toxicities.

RESULTS

The 5-year biochemical failure free survival (BFFS) was 86% for patients treated with EBRT + LDR and 72% for patients treated with EBRT (P = 0.03). Both treatments were associated with comparable incidences of late genitourinary (GU) side effects (18-19%). Late rectal toxicity was decreased by 15% in patients treated with EBRT + LDR (P = 0.0003).

CONCLUSIONS

These results support EBRT followed by brachytherapy boost as a safe and effective method for dose escalation in the treatment of prostate cancer.

[Prostate cancer. Treatment]

The discovery and the utilisation of the prostate specific antigen (PSA) that allows early diagnosis of prostate cancer, have considerably improved the management of this disease. Before the PSA era, prostate cancer was just a disease of the old man, generally detected at an advanced stage and incurable, with a fatal outcome delayed by the androgenic deprivation. Since early 1990's, prostate cancer has become primarily a disease of the man of 60 years, detectable earlier, and curable provided no extraprostatic dissemination has occurred. Early treatment of prostate cancer has benefited from important advances in surgical and radio-therapeutic techniques (conformational irradiation, brachytherapy), with, as principal goal, the combination of a better survival and the reduction of the potential adverse effects that alter quality of life. A better definition of the characteristics of the tumours in terms of progression regarding various parameters (clinical stage, PSA, tumoral differentiation) have resulted, despite the heterogeneity of the disease, in the determination of subgroups of tumours with different prognosis, which leads to an improved therapeutic strategy. The assessment of men's life expectancy (< or > 10 years) is the second primary parameter on which is based the indication for curative or non curative therapy in case of localized tumour. Roughly, before the age of 75, a curative therapy is indicated whereas after this age a surveillance is reasonable as first-line treatment, followed by hormone therapy in case of onset of symptoms indicating some progression of the disease (urinary symptoms, bone lesion). At a Later stage, in case of a metastatic or locally advanced cancer, hormone therapy by androgenic deprivation is highly indicated. The hormone sensitivity characterizes prostate cancer; it has been discovered more than 50 years ago by Charles Huggins (Nobel prize-winner). This hormone therapy is a palliative treatment since its efficacy is transient (ineluctable occurrence of hormone resistance in a variable time delay), but it constitutes an essential therapeutic means with a well-established efficacy. Hormone therapy has progressively improved, with the renunciation of oestrogen therapy and surgical castration which has been replaced by luteinizing hormone-releasing hormone (LH-RH) analogues, and/ or anti-androgens. Numerous works have resulted in a better rationalization of the prescription (date of treatment initiation, interest of combined androgenic deprivation, ...) but uncertainties remain, such as the therapeutic interest of intermittent treatment, or of earlier hormone therapy combined with the treatment of the primitive tumour (adjuvant hormone therapy). Finally, at the time of the hormonal escape of which the molecular mechanisms remain unclear, no therapy has proven any efficacy in survival lengthening, and the treatment remains palliative and symptomatic. Although improved knowledge of prostate cancer aetiology is expected for a real disease prevention, early diagnosis at a curable stage of the disease (by PSA assessment) remains the only means for mortality reduction.

Hyperbaric oxygen therapy in the treatment of radio-induced lesions in normal tissues: a literature review

Late complications are one of the major factors limiting radiotherapy treatment, and their treatment is not codified. Hyperbaric oxygen (HBO) has been used in combination with radiotherapy for over half a century, either to maximise its effectiveness or in an attempt to treat late complications. In this latter case, retrospective trials and case reports are prevailing in literature. This prompted European Society for Therapeutic Radiotherapy and Oncology and European Committee for Hyperbaric Medicine to organise a consensus conference in October 2001, dealing with the HBO indications on radiotherapy for the treatment and prevention of late complications. This updated literature review is part of the documents the jury based its opinion on. A systematic search was done on literature from 1960 to 2004, by only taking into account the articles that appeared in peer review journals. Hyperbaric oxygen treatment involving complications to the head and neck, pelvis and nervous system, and the prevention of complications after surgery in irradiated tissues have been studied. Despite the small number of controlled trials, it may be indicated for the treatment of mandibular osteoradionecrosis in combination with surgery, haemorrhagic cystitis resistant to conventional treatments and the prevention of osteoradionecrosis after dental extraction, whose level of evidence seems to be the most significant though randomised trials are still necessary. The other treatment methods are also outlined for each location.

Treatment outcomes of three-dimensional conformal radiotherapy for localized prostate carcinoma

BACKGROUND

The current study documented the implementation of three-dimensional conformal radiotherapy and assessed the tumor control and toxicity of such treatment in a large, multisite community practice.

METHODS

The authors retrospectively reviewed their first 222 consecutive patients with clinically localized (N0) prostate carcinoma treated with a 6-field conformal technique from October 1993 through March 2000. Standardized target definitions, dose planning constraints, and gantry angles were utilized to develop the treatment plan. Patients were categorized by low, intermediate, and high risk. Low risk was defined as T1a-T2a disease, a Gleason score < 7, and prostate-specific antigen (PSA) level </= 10.0 ng/mL (n = 47 [21%]). Intermediate risk was defined as T2b disease, a Gleason score > 6, or PSA level > 10.01 ng/mL (n = 60 [27%]). High risk was defined as 2 of the above risk factors or as T3 disease, a Gleason score > 7, or a PSA level > 20 (n = 115 [52%]). Biochemical disease recurrence was defined in accordance with the American Society for Therapeutic Radiology and Oncology definition. Urinary and bowel toxicity were graded using the Radiation Therapy Oncology Group morbidity scoring system.

RESULTS

The median follow-up after radiotherapy for surviving patients was 47 months (range, 0-99 months). The 2 and 5-year actuarial biochemical control rates for all patients were 84% and 78%, respectively. Using logistic regression analysis, lower dose (< 75.6 gray [Gy] vs. 75.6 Gy; P = 0.006), higher risk group (P = 0.033), higher stage (P = 0.045), and higher PSA level (P = 0.001) were significantly associated with biochemical disease recurrence. Toxicity was not significantly correlated with a higher radiotherapy dose.

CONCLUSIONS

Dose escalation to 75.6 Gy using a 6-field conformal technique was feasible in the authors' community practice and resulted in acceptable toxicity and early biochemical outcomes.

Historia natural del cáncer de próstata localizado. datos preliminares de progresión y mortalidad

OBJECTIVE

To address the effect of therapy options and other factors on the natural history of localized prostate cancer (PCa).

METHODS

Men with diagnosed clinically localized PCa who underwent radical prostatectomy (RP), radiotherapy (RT) or watchful waiting (WW). Rates of biochemical progression (BQP) and clinical progression (CLP) were calculated. The effects of therapy, initial PSA, presence of palpable tumor and Gleason score were assessed with Kaplan-Meier analysis and log-rank test. Similar methods were used to study overall and disease-specific survival.

RESULTS

A total of 228 patients were studied (135 underwent RP, 46 RT, and 47 WW). Median followup time was 2.5 years. Forty patients presented with BQP. The probability of being free from BQP after 2 and 5 years was 76.8% and 57.9% respectively for the whole population, 70.9% and 57.6% for RP patients, 100% and 100% for RT, and 87.1% and 47.2% for WW (p = 0.031). Nineteen patients presented with CLP, with no significant differences with regard to therapy option. A poorly differentiated Gleason score favoured the probability of presenting with CLP (p = 0.022) and shift to metastatic disease (p < 0.001). No cancer-specific mortality was recorded in the studied population.

CONCLUSIONS

Short and medium-term prognosis is excellent for localized prostate cancer in terms of survival. Nevertheless, some patients show a higher risk of progressing to metastatic disease (poorly differentiated Gleason score).

Does short-term androgen deprivation substitute for radiation dose in the treatment of high-risk prostate cancer?

PURPOSE

Randomized trials have corroborated the clinical benefit of adding androgen deprivation (AD) to radiotherapy (RT) in the treatment of high-risk prostate cancer. Another competing strategy is to escalate the RT dose using three-dimensional conformal RT (3D-CRT). In this analysis, we asked whether the addition of short-term AD (STAD) (<or=6 months) to RT in the treatment of high-risk (prostate-specific antigen >20 ng/mL, Gleason score 8-10, or T3-4) prostate cancer is an effective substitute for dose escalation.

METHODS AND MATERIALS

Between March 1, 1990 and November 30, 1998, 296 high-risk prostate cancer patients were treated with 3D-CRT alone (n = 206) or in combination with STAD (n = 90). The patient characteristics were median age 68 years, median follow-up 58 months, pretreatment initial prostate-specific antigen 21.8 ng/mL, RT dose 75 Gy, STAD duration 3 months, and time off STAD 64 months. The impact of STAD with respect to dose was examined using univariate analysis for dose ranges of <75 Gy and >or=75 Gy. Stepwise Cox proportional hazards regression multivariate analysis was performed to determine independent correlates of freedom from biochemical failure (bNED), freedom from distant metastasis (FDM), and overall survival. In a separate matched-pair analysis (n = 44 per group), those treated to <75 Gy + STAD (Group A) were compared with those who received >or=75 Gy alone (Group B).

RESULTS

On univariate analysis, the addition of STAD had no impact on bNED, FDM, or overall survival in either dose group. On multivariate analysis, initial prostate-specific antigen level, palpation T stage, and RT dose were significant correlates of bNED. For FDM and overall survival, the significant covariates were palpation T stage and Gleason score, respectively. Finally, in matched-pair analysis, the higher RT dose group had a significantly greater bNED rate at 5 years (Group A 35% vs. Group B 57%, p = 0.0190).

CONCLUSION

Our data suggest that STAD, as used here (median 3 months), is not a substitute for RT dose in the treatment of high-risk prostate cancer. RT dose is an essential element in the treatment of high-risk prostate cancer.

Do older men benefit from curative therapy of localized prostate cancer?

PURPOSE

Prior decision-analytic models are based on outdated or suboptimal efficacy, patient preference, and comorbidity data. We estimated life expectancy (LE) and quality-adjusted life expectancy (QALE) associated with available treatments for localized prostate cancer in men aged >/= 65 years, adjusting for Gleason score, patient preferences, and comorbidity.

METHODS

We evaluated three treatments, using a decision-analytic Markov model: radical prostatectomy (RP), external beam radiotherapy (EBRT), and watchful waiting (WW). Rates of treatment complications and pretreatment incontinence and impotence were derived from published studies. We estimated treatment efficacy using three data sources: cancer registry cohort data, pooled case series, and modern radiotherapy studies. Utilities were obtained from 141 prostate cancer patients and from published studies.

RESULTS

For men with well-differentiated tumors and few comorbidities, potentially curative therapy (RP or EBRT) prolonged LE up to age 75 years but did not improve QALE at any age. For moderately differentiated cancers, potentially curative therapy resulted in LE and QALE gains up to age 75 years. For poorly differentiated disease, potentially curative therapy resulted in LE and QALE gains up to age 80 years. Benefits of potentially curative therapy were restricted to men with no worse than mild comorbidity. When cohort and pooled case series data were used, RP was preferred over EBRT in all groups but was comparable to modern radiotherapy.

CONCLUSION

Potentially curative therapy results in significantly improved LE and QALE for older men with few comorbidities and moderately or poorly differentiated localized prostate cancer. Age should not be a barrier to treatment in this group.

High dose rate brachytherapy in the treatment of prostate cancer

The optimal treatment of patients with localized prostate cancer remains controversial. Significant clinical data are available, however, demonstrating that patients treated with radiation therapy (RT) have a significantly better outcome as the dose to the gland is increased. What remains debatable, however, is how to best deliver these higher doses of RT without significantly increasing normal tissue toxicities. Conformal high dose rate brachytherapy (C-HDR BT) represents an alternative means of precise dose delivery that offers similar tumoricidal effects as three-dimensional (3D) conformal external beam radiotherapy (EBRT) or permanent interstitial prostate seed implants with potential additional advantages. Since C-HDR BT consists of temporarily placing afterloading needles or catheters directly into the prostate gland under real-time ultrasound guidance, a steep dose gradient between the prostate and adjacent normal tissues can be generated that is minimally affected by organ motion and edema or treatment setup uncertainties. The ability to control the amount of time the single HDR radioactive source "dwells" at each position along the length of each brachytherapy catheter further enhances the conformity of the dose. In addition, recent radiobiological data on prostate cancer treatment suggest that C-HDR BT should produce tumor control and late normal tissue side effects that are at least as good as achieved with conventional fractionation, with the additional possibility that acute side effects might be reduced. Published data from several groups performing C-HDR BT as boosts in patients with locally advanced disease have supported these assumptions. Combined with the physical advantages discussed above, C-HDR BT should provide similar tumor control as 3D conformal EBRT with the added advantages of reduced treatment times, less acute toxicity, and no additional technological requirements to account and correct for treatment setup uncertainties and organ motion. Due to the success of C-HDR BT as boost treatment in locally advanced disease, this form of radiation treatment has recently been applied to low-risk prostate cancer patients as an alternative brachytherapy technique to permanent interstitial seed implantation. Advantages in this setting include an improved ability to define and deliver the prescribed dose, a significantly shortened treatment schedule compared to 3D conformal EBRT, and the fact that patients are not radioactive after implantation.

Alternative therapies for localized prostate cancer

Prostate cancer is the leading malignancy in men; an increase in detected localized prostate cancers is expected in the years to come. Radical prostatectomy, although effective, is associated with a considerable morbidity. The aim of minimal invasive alternative treatment options should be equal efficacy, but a decrease in side effects. Cryosurgical ablation of the prostate, brachytherapy, high-intensity focused ultrasound, and radiofrequency interstitial tumor ablation were evaluated after a literature review from a MEDLINE search (1966-2002). When compared with treatments in the 1960s and 1970s, increased safety is observed in all of the alternative treatments available today. Sophisticated technology, including the latest ultrasonography devices for exact planning and monitoring of treatment, contributes largely to this safety. Five-year results of cryosurgical ablation of the prostate show a prostate-specific antigen lower than 1 ng/mL in 60% of the cases; in the third generation, there are no long-term data available on cryosurgical ablation of the prostate. Recent outcome data of brachytherapy come close to results of radical prostatectomy series. Brachytherapy is the only true alternative at this point in time. High-intensity focused ultrasound and radiofrequency interstitial tumor ablation are promising new technologies that have proven to be able to induce extensive necrosis; however, follow-up is too short to determine their definite places in the treatment of prostate cancer.

Dose response in prostate cancer with 8–12 years’ follow-up

PURPOSE

This communication reports the long-term results of the original group of prostate cancer patients who participated in the first prospective Fox Chase Cancer Center radiation dose escalation study for which 8-12 years of follow-up is now available.

METHODS AND MATERIALS

Between March 1, 1989 and October 31, 1992, 232 patients with clinically localized prostate cancer received three-dimensional conformal radiotherapy only at Fox Chase Cancer Center in a prospective dose-escalation study. Of these patients, 229 were assessable. The 8-, 10-, and 12-year actuarial rates of biochemical control (biochemically no evidence of disease [bNED]), freedom from distant metastasis (FDM), and morbidity were calculated. The Cox proportional hazards model was used to assess multivariately the predictors of bNED control and FDM, including pretreatment prostate-specific antigen (PSA) level (continuous), tumor stage (T1/T2a vs. T2b/T3), Gleason score (2-6 vs. 7-10), and radiation dose (continuous). The median total dose for all patients was 74 Gy (range 67-81). The median follow-up for living patients was 110 months (range 89-147). bNED control was defined using the American Society for Therapeutic Radiology and Oncology consensus definition.

RESULTS

The actuarial bNED control for all patients included in this series was 55% at 5 years, 48% at 10 years, and 48% at 12 years. Patients with pretreatment PSA levels of 10-20 ng/mL had statistically significant differences (19% vs. 31% vs. 84%, p = 0.0003) in bNED control when stratified by dose (<71.5, 71.5-75.6, and > 75.6 Gy, respectively) on univariate analysis. For the 229 patients with follow-up, 124 (54%) were clinically and biochemically without evidence of disease. Sixty-nine patients were alive at the time of last follow-up, and 55 patients were dead of intercurrent disease. On multivariate analysis, radiation dose was a statistically significant predictor of bNED control for all patients and for unfavorable patients with a pretreatment PSA <10 ng/mL. For the patients with a pretreatment PSA level of 10-20 ng/mL, the radiation dose was a statistically significant predictor across all groups. No radiation dose response was seen for those patients with a pretreatment PSA level >20 ng/mL, although large numbers of patients are required to demonstrate a difference. The radiation dose, Gleason score, and palpation T stage were significant predictors for the entire patient set, as well as for those with pretreatment PSA levels between 10 and 20 ng/mL. The FDM rate for all patients included in this series was 89%, 83%, and 83% at 5, 10, and 12 years, respectively. For patients with pretreatment PSA levels <10 ng/mL, all four covariates (radiation dose, Gleason score, pretreatment PSA, and palpation T stage) were significant predictors of distance metastasis. Using the Radiation Therapy Oncology Group morbidity scale, no difference was noted in the frequency of Grade 2 and 3 genitourinary and Grade 3 gastrointestinal morbidity when patients in this data set were stratified by radiation dose. However, a significant increase occurred in Grade 2 gastrointestinal complications as the radiation dose increased.

CONCLUSION

The long-term results of the original Fox Chase radiation dose escalation study with >9 years of median follow-up confirm the existence of a dose response for both bNED control and FDM. The dose response in prostate cancer is real, and the absence of biochemical recurrence after 8 years demonstrates the lack of late failure and suggests cure.

The use of conformal radiotherapy and the selection of radiation dose in T1 or T2 low or intermediate risk prostate cancer – a systematic review

BACKGROUND AND PURPOSE

The purpose was to develop a systematic review that would address the following questions: (a) when single-modality treatment external-beam radiotherapy is selected as the modality of choice, what is the role of three-dimensional (3D) conformal radiotherapy in treating clinically localized (T1, T2/NO, NX/MO) prostate cancer? The outcomes of interest are biochemical freedom from failure (bNED) rates, clinical recurrence-free survival, disease-specific survival and acute and late toxicity; (b) what is the appropriate dose and fractionation prescription in this clinical setting?

MATERIALS AND METHODS

A systematic review of the English published literature was undertaken to provide evidence relevant to the above outcomes.

RESULTS

One randomized controlled trial comparing conventional radiotherapy to conformal therapy with dose escalation reported bNED rates. Three additional randomized controlled trials reported acute or chronic late outcome assessments. Additionally, phase II studies of dose escalation in sequential patient cohorts and non-randomized comparative assessments of dose-response and bNED rates in controlled analyses were reviewed. There is convincing evidence from randomized trials that the use of conformal therapy reduces acute and late treatment-related morbidity. There is preliminary evidence suggesting that when external-beam therapy alone is used to treat patients, conformal therapy with dose-escalation is more efficacious than doses of 70Gy. The increased efficacy appears to be predominantly seen in the subset of patients with intermediate-risk disease (PSA 10-20). There is conflicting evidence of the efficacy of dose-escalation in patients with low initial PSA (<10) and in patients with initial PSA greater than 20. Conformal radiotherapy at a dose of 78Gy appears to be relatively safe with no increase in acute or late effects compared with conventional treatment (up to 70Gy) so long as appropriate technological principles are considered.

CONCLUSIONS

Patients who have external-beam radiotherapy should be treated using a 3D conformal technique. Patients with intermediate-risk disease (PSA 10-20) who are treated with external-beam radiotherapy alone should be offered doses of 75-78Gy in 180-200cGy fractions.

Three-Dimensional Conformal Therapy Versus Standard Radiation Therapy in Localized Carcinoma of Prostate: An Update

This study updates technical principles and results of 3-dimensional conformal radiation therapy (3D-CRT) in localized carcinoma of the prostate. Between January 1992 and December 1999, 312 patients were treated with 3D-CRT and 135 patients were treated with bilateral arcs standard radiation therapy (SRT) alone for clinical stage T1b-c or T2 histologically confirmed prostate cancer. None of these patients received hormonal therapy. Mean follow-up for patients in the 3D-CRT group was 3.2 years (range, 2-5.9 years) and for SRT patients, 4.7 years (range, 4-7 years). For 3D-CRT, 7 intersecting fields were used (cerrobend blocking or multileaf collimation) to deliver 68-74 Gy to the prostate. Standard radiation therapy consisted of bilateral 120 degree rotational arcs, with portals using 2-cm margins around the prostate to deliver 68-70 Gy to the prostate. The criterion for chemical disease-free survival was a postirradiation prostate-specific antigen (PSA) value following the American Society for Therapeutic Radiology and Oncology guidelines. Symptoms during treatment were quantitated weekly, and late effects were assessed every 4-6 months. Dose-volume histograms showed a two-thirds reduction with 3D-CRT in normal bladder or rectum receiving > or = 70 Gy with 3D-CRT. Higher 5-year chemical disease-free survival was observed with 3D-CRT (75%; for T1b-c and 79%; for T2 tumors) compared with SRT (61% and 65%, P = 0.01 and P = 0.12, respectively). There was no statistically significant difference in chemical disease-free survival in patients with Gleason score of < or = 4 (P = 0.85), but, with Gleason score of 5-7, the 5-year survival rates were 83% with 3D-CRT and 59% with SRT (P < or = 0.01). In 245 patients with pretreatment PSA of < or = 10 ng/mL treated with 3D-CRT, the chemical disease-free rate was 80% versus 72% in 98 patients treated with SRT (P = 0.21). In patients with PSA of 10.1-20 ng/mL, the chemical disease-free survival rate for 50 patients treated with 3D-CRT was 71% compared with 43% for 20 patients treated with SRT (P = 0.02). The corresponding values were 59% and 16%, respectively, for patients with PSA levels > 20 ng/mL (P = 0.09). On multivariate analysis, the most important prognostic factors for chemical failure were pretreatment PSA (P = 0.004), nadir PSA (P = 0.001), and 3D-CRT technique (P = 0.012). Moderate dysuria was reported by 2%-5% of patients treated with 3D-CRT in contrast to 6%-9% of patients treated with SRT. The incidence of moderate loose stools or diarrhea, usually after the fourth week of treatment, was 3%-5% in the 3D-CRT patients and 8%-19% in the SRT group. Late intestinal grade 2 morbidity (proctitis or rectal bleeding) was 1% in the 3D-CRT group in contrast to 7% in SRT patients. The 3D-CRT spares more normal tissues, yields higher chemical disease-free survival, and results in less treatment morbidity than SRT in treatment of stage T1-T2 prostate cancer. Follow-up at > or = 10 years is needed to confirm these observations.

Comparing the costs of radiation therapy and radical prostatectomy for the initial treatment of early-stage prostate cancer

PURPOSE

Radical prostatectomy and external-beam radiation are the most common treatments for localized prostate cancer. Given the absence of clinical consensus in favor of one treatment or the other, relative costs may be a significant factor. This study compares the direct medical costs during the month before and 9 months after diagnosis for patients treated primarily with external-beam radiation or radical prostatectomy for early-stage prostate cancer.

METHODS

Patients age 65 or older and coded by the Surveillance, Epidemiology, and End Results (SEER) registry as having been diagnosed with adenocarcinoma of the prostate treated primarily with external-beam radiation or radical prostatectomy during 1992 and 1993 were identified. The initial treatment costs, as measured by Medicare-approved payment amounts, for each strategy were analyzed using linked SEER-Medicare claims data after adjusting for differences in comorbidity and age. An intent-to-treat analysis was also performed to adjust for differences in staging between the two groups.

RESULTS

For patients in the treatment-received analysis, the average costs were significantly different; $14,048 (95% confidence interval [CI], $13,765 to $14,330) for radiation therapy and $17,226 (95% CI, $16,891 to $17,560) for radical prostatectomy (P <.001). The average costs for patients in the intent-to-treat analysis were also significantly less for radiation therapy patients ($14,048; 95% CI, $13,765 to $14,330) than for those who underwent radical prostatectomy ($17,516; 95% CI, $17,195 to $17,837; P <.001).

CONCLUSION

For patients with early-stage prostate cancer, average costs during the initial treatment interval were at least 23% greater for radical prostatectomy than for external-beam radiation. Major limitations of the research include not studying costs after the initial treatment interval and questionable current applicability, given changes in management of early prostate cancer.

Advantages of using noncoplanar vs. axial beam arrangements when treating prostate cancer with intensity-modulated radiation therapy and the step-and-shoot delivery method

PURPOSE

The focus of this work was to compare noncoplanar beam arrangements used for intensity-modulated radiation therapy (IMRT) step-and-shoot delivery to several axial beam arrangements used in the treatment of clinically localized prostate cancer.

METHODS AND MATERIALS

A 5-field coronal crossfire beam arrangement was developed for IMRT with the objective of improving upon the rectal and bladder dose-volume histograms obtained using 5-, 7-, and 9-field axial beam arrangements. Additionally, a modified 7-field crossfire technique was developed yielding improved dose distributions. The average values of dose-volume histograms and the time for treatment delivery were evaluated for all plans for 10 randomly chosen patients.

RESULTS

Both crossfire IMRT techniques exhibited a 15-25% decrease in dose to the hottest 10% and 20% of the rectum relative to all three axial IMRT techniques. The 5-field crossfire orientation yields slightly higher bladder doses when compared to the other techniques. In selected cases, the 7-field crossfire beam arrangement demonstrates decreased dose to the bladder when compared to all three axial techniques. A mean delivery time of 14 to 17.5 min is noted for the noncoplanar arrangements after positioning and localization.

CONCLUSIONS

A technique is described that allows additional normal tissue sparing during dose escalation to the prostate during IMRT delivery. This technique takes advantage of the spatial orientation between the prostate, rectum, and bladder. With patient setup and target localization time aside, a mean treatment time of 14 to 17.5 min allows the delivery of the crossfire plans to conform to standard treatment times.

[Conformal radiotherapy in prostate cancer: for whom and how?]

External radiotherapy is one of the modalities used to cure localized prostate carcinoma. Most of localized prostate carcinomas, specially those of the intermediate prognostic group, may benefit from escalated dose above 70 Gy at least as regard biochemical and clinical relapse free survival. 3D-CRT allows a reduction of the dose received by organs at risk and an increase of prostate dose over 70 Gy. It is on the way to become a standard. Intensity modulated radiation therapy increases dose homogeneity and reduces rectal dose. These methods necessitate rigorous procedures in reproducibility, delineation of volumes, dosimetry, daily treatment. They need also technological and human means. It is clear that localized prostate cancer is a good example for evaluation of these new radiotherapy modalities.

[Clinical and biological surveillance after radiotherapy for localized prostate cancer]

Serum PSA is an excellent marker of disease status after external beam radiotherapy or brachytherapy for patients with prostate carcinoma. A low PSA nadir < or = 1 even < or = 0.5 ng/mL has been shown to be as a surrogate end point for disease control. Three successive increases of this marker after achieving the nadir defines recurrence as recommended by the American Society for Therapeutic Radiology and Oncology. The biochemical relapse or PSA failure after treatment precedes clinical disease relapse by several months. PSA profile or kinetics may have implications for patterns of failure and prognosis. Prostate post-radiotherapy biopsies should not be part of routine follow-up as its interpretation is frequently problematic. Other exams should not be performed unless clinical symptoms are present. Post-radiotherapy relapse treatment has generally no curative intent.

Risk group dependence of dose-response for biopsy outcome after three-dimensional conformal radiation therapy of prostate cancer

BACKGROUND AND PURPOSE

We fit phenomenological tumor control probability (TCP) models to biopsy outcome after three-dimensional conformal radiation therapy (3D-CRT) of prostate cancer patients to quantify the local dose-response of prostate cancer.

MATERIALS AND METHODS

We analyzed the outcome after photon beam 3D-CRT of 103 patients with stage T1c-T3 prostate cancer treated at Memorial Sloan-Kettering Cancer Center (MSKCC) (prescribed target doses between 64.8 and 81Gy) who had a prostate biopsy performed >or=2.5 years after end of treatment. A univariate logistic regression model based on D(mean) (mean dose in the planning target volume of each patient) was fit to the whole data set and separately to subgroups characterized by low and high values of tumor-related prognostic factors T-stage (<T2c vs. >or=T2c), Gleason score (<or=6 vs. >6), and pre-treatment prostate-specific antigen (PSA) (<or=10 ng/ml vs. >10 ng/ml). In addition, we evaluated five different classifications of the patients into three risk groups, based on all possible combinations of two or three prognostic factors, and fit bivariate logistic regression models with D(mean) and the risk group category to all patients. Dose-response curves were characterized by TCD(50), the dose to control 50% of the tumors, and gamma(50), the normalized slope of the dose-response curve at TCD(50).

RESULTS

D(mean) correlates significantly with biopsy outcome in all patient subgroups and larger values of TCD(50) are observed for patients with unfavorable compared to favorable prognostic factors. For example, TCD(50) for high T-stage patients is 7Gy higher than for low T-stage patients. For all evaluated risk group definitions, D(mean) and the risk group category are independent predictors of biopsy outcome in bivariate analysis. The fit values of TCD(50) show a clear separation of 9-10.6Gy between low and high risk patients. The corresponding dose-response curves are steeper (gamma(50)=3.4-5.2) than those obtained when all patients are analyzed together (gamma(50)=2.9).

CONCLUSIONS

Dose-response of prostate cancer, quantified by TCD(50) and gamma(50), varies by prognostic subgroup. Our observations are consistent with the hypothesis that the shallow nature of clinically observed dose-response curves for local control result from a patient population that is a heterogeneous mixture of sub-populations with steeper dose-response curves and varying values of TCD(50). Such results may eventually help to identify patients, based on their individual pre-treatment prognostic factors, that would benefit most from dose-escalation, and to guide dose prescription.

Verification of prostate treatment setup using computed radiography for portal imaging

A non-film-based system was used to obtain high quality portal film images. Digital portal images were obtained with a computed radiography (CR) system, in which the film is replaced with a photostimulable phosphor plate. Digital processing of portal images enhanced the display contrast using regional histogram equalization. The images were compared to images on radiographic film, exposed in the same cassette. The contrast-enhanced CR images of prostate treatment fields facilitated identification of the entire contour of the ischium, the location of the pubic symphysis, and the ischial tuberosity to determine the anterior and inferior locations of the prostate and bladder. Identifying the coccyx on the processed portal images permits the physician to locate accurately the posterior wall of the rectum. In each case the quality of the CR image was judged by the clinician to be superior to conventional portal film. The identification of these anatomical structures on the portal images is clinically important for verifying 3D conformal therapy of the prostate. With the same CR system one may acquire digital treatment portal and simulation images. This provides a foundation for a picture archival communication system for radiation oncology. Existing software can be used to register these digital portal and simulation images to facilitate verification of treatment setup.

Comprehensive comparison of health-related quality of life after contemporary therapies for localized prostate cancer

PURPOSE

Health-related quality-of-life (HRQOL) concerns are pivotal in choosing prostate cancer therapy. However, concurrent HRQOL comparison between brachytherapy, external radiation, radical prostatectomy, and controls is hitherto lacking. HRQOL effects of hormonal adjuvants and of cancer control after therapy also lack prior characterization.

PATIENTS AND METHODS

A cross-sectional survey was administered to patients who underwent brachytherapy, external-beam radiation, or radical prostatectomy during 4 years at an academic medical center and to age-matched controls. HRQOL among controls was compared with therapy groups. Comparison between therapy groups was performed using regression models to control covariates. HRQOL effects of cancer progression were evaluated.

RESULTS

One thousand fourteen subjects participated. Compared with controls, each therapy group reported bothersome sexual dysfunction; radical prostatectomy was associated with adverse urinary HRQOL; external-beam radiation was associated with adverse bowel HRQOL; and brachytherapy was associated with adverse urinary, bowel, and sexual HRQOL (P < or =.0002 for each). Hormonal adjuvant symptoms were associated with significant impairment (P <.002). More than 1 year after therapy, several HRQOL outcomes were less favorable among subjects after brachytherapy than after external radiation or radical prostatectomy. Progression-free subjects reported better sexual and hormonal HRQOL than subjects with increasing prostate-specific antigen (P <.0001).

CONCLUSION

Long-term HRQOL after prostate brachytherapy showed no benefit relative to radical prostatectomy or external-beam radiation and may be less favorable in some domains. Hormonal adjuvants can be associated with significant impairment. Progression-free survival is associated with HRQOL benefits. These findings facilitate patient counseling regarding HRQOL expectations and highlight the need for prospective studies sensitive to urinary irritative and hormonal concerns in addition to incontinence, sexual, and bowel HRQOL domains.

Does age influence the behaviour of localized prostate cancer?

OBJECTIVE

To assess, in a meta-analysis of published studies, whether age influences the behaviour of localized prostate cancer.

METHODS

The Medline database was searched from 1966 to 2000 to identify studies analysing the outcome of localized prostate cancer by age, using disease-specific outcome measures, and having controlled for the established prognostic factors of grade, T stage and, where available, serum prostate-specific antigen (PSA) level.

RESULTS

In all, 34 studies were identified, which included a total of 27 551 patients. The incomplete and heterogeneous nature of the reports precluded any quantitative overview. The findings of these reports are described and methodological shortcomings discussed.

CONCLUSION

The evidence suggests that young age was an adverse prognostic factor in some series of radiation therapy before the advent of PSA assays, when men typically presented clinically with locally advanced disease, but that age has no significant prognostic effect in contemporary series of localized prostate cancer. Possible explanations for this difference are discussed, together with implications for further studies.

The economic costs of early stage prostate cancer

The economic costs of early stage prostate cancer are significant, and will likely increase as the proportion of older men grows in the population of industrialised nations. In the US, total costs have been estimated to range from US dollars 1.72 billion to US dollars 4.75 billion annually (1990 costs). Costs related to early stage prostate cancer arise from screening, staging and treatment. Cost-effectiveness models of population-based prostate cancer screening indicate that such screening could result in as much as US dollars 27.9 billion (1988 values) in charges to the US healthcare system. Evidence-based cancer-staging strategies would result in significant reduction of wasted expense. Rational allocation of healthcare dollars for prostate cancer screening and treatment may ultimately depend on data from randomised controlled trials.

The rush to judgment: Does the evidence support the enthusiasm over three-dimensional conformal radiation therapy and dose escalation in the treatment of prostate cancer?

PURPOSE

To discuss the assumptions behind and current clinical evidence on three-dimensional conformal radiation therapy (3D-CRT) and dose escalation in the treatment of prostate cancer.

METHODS

We first define 3D-CRT in comparison to standard radiation therapy and discuss the assumptions on which the technology of 3D-CRT and dose escalation are based. We then examine the evidence on the benefits and limitations from the current most commonly cited studies on dose-escalation trials to treat prostate cancer.

RESULTS

The assumption that 3D-CRT can provide a tighter margin around the tumor area to allow for dose escalation is not yet proven by studies that show continual difficulty in defining the planning treatment volume because of extrinsic and intrinsic difficulties, such as imaging variabilities and patient and organ movement. Current short-term dose-escalation studies on the use of 3D-CRT to treat prostate cancer are limited in their ability to prove that increasing dose improves survival and does not incur potential long-term complications to normal tissue.

CONCLUSION

Although 3D-CRT is a promising technology that many radiation oncologists and clinics are quickly adopting to treat such tumors as prostate cancer, the long-term evidence on the benefits and limitations of this technology is still lacking. Until we have solid long-term evidence on the true clinical potential of this new technology, let us not rush to judgment, but exercise caution, diligence, and thoughtfulness in using this new technology to treat our patients.

External-beam radiotherapy in the management of carcinoma of the prostate

BACKGROUND

External-beam radiotherapy (EBRT) has been used in the treatment of adenocarcinoma of the prostate gland for more than 30 years. Well-documented clinical series have demonstrated the effectiveness of EBRT in achieving both cause-specific survival and freedom from biochemical (prostate-specific antigen [PSA]) progression.

METHODS

The indications and expected treatment results for treatment by EBRT in the management of adenocarcinoma of the prostate gland are reviewed. The treatment of early-stage disease definitively by EBRT alone or as complement to radioactive seed implant is emphasized. In the management of locally advanced disease, the use of EBRT with combined androgen ablation is discussed as definitive therapy and also as indicated in the postoperative adjuvant management of surgically identified pathologic stage T3 disease.

RESULTS

The relative clinical benefit of EBRT compared with the mostly predictable and well-defined moderate side effects, which are manageable in most instances by conservative measures treatment, is well established. Advances in defining radiation-beam parameters have led to more effective and safer treatment for prostate cancer.

CONCLUSIONS

EBRT has historically been a mainstay in the management of prostate cancer. It remains a useful and indicated treatment modality in patients with early-stage, locally advanced, and metastatic disease.

Defining the optimal radiation dose with three-dimensional conformal radiation therapy for patients with nonmetastatic prostate carcinoma by using recursive partitioning techniques

BACKGROUND

The objective of this study was to determine the effect of dose and its interaction with known prognostic variables, including pretreatment prostate specific antigen (PSA), Gleason score (GS), and T classification, on patients with nonmetastatic prostate carcinoma treated with three-dimensional conformal radiation therapy (3DCRT) alone using recursive partitioning analysis.

METHODS

Between November 1987 and November 1997, 939 patients with nonmetastatic prostate carcinoma were treated with 3DCRT alone at Fox Chase Cancer Center. Biochemical no evidence of disease (bNED) control was defined using the American Society of Therapeutic Radiology and Oncology Consensus definition. Recursive partitioning analysis was used to identify subgroups with similar risks of bNED failure. Prognostic factors used in the model included pretreatment PSA, GS, T classification, and radiation dose. The median follow-up was 47 months (range, 2-133 months).

RESULTS

Twelve terminal nodes of the decision tree were merged to form four prognostic groups with similar bNED control rates. The 5-year actuarial rates of bNED control rates for Groups I, II, III, and IV were 84%, 41%, 16%, and 67%, respectively (P < 0.0001). Increasing the dose to greater than 7235 centigray (cGy) improved bNED control rates for patients with PSA levels of 10-19.9 ng/mL and T1/2a classification disease. Increasing the dose to greater than 7629 cGy improved bNED control rates for patients with T2b/3 classification disease with PSA levels less than 20 ng/mL. Patients with PSA levels greater than or equal to 20 ng/mL need high-dose 3DCRT. For those patients with GS 2-6 and T1/2a classification disease, treatment with greater than 7400 cGy resulted in 67% bNED control rate versus 16% at 5 years for treatment with less than 7400 cGy. High radiation dose (> 7700 cGy) improved bNED control rate from 16% to 41% for patients with high-risk disease (PSA > or = 20 ng/mL and GS 7-10) at 5 years.

CONCLUSIONS

The authors showed that with recursive partitioning techniques radiation dose continues to be an important predictor of bNED control rate and that a radiation dose response for patients with clinically localized prostate carcinoma exists. Patients with one or more prognostic feature (PSA > 10 ng/mL, classification T2b/T3, GS 7-10, or the presence of perineural invasion) achieve similar rates of bNED control compared with those patients with lower volume disease when radiation dose is increased.

Treatment planning aids in prostate cancer: friend or foe?

BACKGROUND

Rectal barium is commonly used as a treatment planning aid for prostate cancer to delineate the anterior rectal wall. Previous research at the Ottawa Regional Cancer Centre demonstrated that retrograde urethrography results in a systematic shift of the prostate. We postulated that rectal barium could also cause prostate motion.

PURPOSE

The study was designed to evaluate the effects of rectal barium on prostate position.

METHODS AND MATERIALS

Thirty patients with cT1-T3 prostate cancer were evaluated. Three fiducial markers were placed in the prostate. During simulation, baseline posterior-anterior and lateral films were taken. Repeat films were taken after rectal barium opacification. The prostate position (identified by the fiducials) relative to bony landmarks was compared before and after rectal barium. Films were analyzed using PIPsPro software.

RESULTS

The rectal barium procedure resulted in a significant displacement of the prostate in the anterior and superior direction. The mean displacement of the prostate measured on the lateral films was 3.8 mm (SD: 4.4 mm) in the superior direction and 3.0 mm (SD: 3.1) in the anterior direction.

CONCLUSIONS

Rectal barium opacification results in a systematic shift of the prostate. This error could result in a geographic miss of the target; therefore, alternate methods of normal tissue definition should be used.

Three dimensional conformal radiotherapy in patients with T2a-b, N0, M0 prostatic carcinoma

The current study was undertaken to evaluate the Prostate Specific Antigen (PSA) relapse free survival and the prognostic factors in a total of 38 patients with stages of T2a-b, N0, M0 prostate carcinoma treated with three-dimensional conformal radiotherapy (3D-CRT). Mean 69.63 Gy was given with 3D-CRT, the mean follow up time was 13.89 months, and the mean prebiopsied PSA level was 25.12 ng/ml. The 2-year PSA relapse free survival was 47.37% for the entire group. The 2-year PSA relapse free survival rates were 100% and 44.74% for the patients with Gleason score < or = 7 and greater than 7 (p < or = 0.05). Patients with prebiopsied PSA level < or = 10 ng/ml and the stages of T2a or T2b did not show any significant differences (p > or = 0.05). Although the few case number and short term follow up, in this study 3D-CRT was a new effective technique to prostate cancer for our institutes and the Gleason score was important predictor of PSA relapse free survival.

Five-year retrospective, multi-institutional pooled analysis of cancer-related outcomes after cryosurgical ablation of the prostate

OBJECTIVES

To define the potential role of cryosurgical ablation of the prostate (CSAP) as a treatment option for patients with localized prostate carcinoma (PCA), we performed a retrospective outcomes analysis of a large database of patients undergoing CSAP constructed from five institutions and compared this with matching outcomes from contemporary reports of patient outcomes after radiotherapy.

METHODS

A total of 975 patients who underwent CSAP as primary therapy from January 1993 to January 1998 with sufficient outcomes data available were identified. Patients were stratified into three groups on the basis of their clinical features. Biochemical-free survival (BFS), post-CSAP biopsy results, and post-CSAP morbidities were calculated and recorded.

RESULTS

The median follow-up for all patients was 24 months. The percentages of patients in the low, medium, and high-risk groups were 25%, 34%, and 41%, respectively. For prostate-specific antigen thresholds of less than 0.5 and less than 1.0 ng/mL, the 5-year actuarial BFS ranged from 36% to 61% and 45% to 76%, respectively, depending on the risk category. Overall, the positive biopsy rate was 18%. Morbidities included impotence in 93%, incontinence in 7.5%, rectourethral fistula in 0.5%, and transurethral resection of the prostate in 13% of patients (10% approved warming catheters versus 40% nonapproved).

CONCLUSIONS

For each risk group, the 5-year BFS and positive biopsy rate after CSAP was comparable to matching outcomes reported after radiotherapy. Morbidities also seemed comparable, with impotence rates higher and rectal injury rates lower after CSAP than after radiotherapy. These data indicate that CSAP can be performed with low morbidity and can produce cancer-related results comparable to those reported for patients undergoing radiotherapy.

Radiation for prostate cancer

The balance between tumour control and normal tissue damage with conventional radiotherapy is critical to outcome and morbidity in the treatment of localised prostate cancer. Recent technological advances have allowed a reduction in the amount of normal tissue included in target treatment volumes. This reduces morbidity and allows dose escalation, theoretically increasing the likelihood of tumour control. The methods used to achieve dose escalation are discussed and the available evidence for their safety and efficacy, relative to conventional treatment, is reviewed. Although there are no randomised studies to provide evidence of increased survival, the available evidence supports the hypothesis that dose escalation produces survival rates equivalent to surgical series and provides a realistic choice for patients.

Toxicity following high-dose three-dimensional conformal and intensity-modulated radiation therapy for clinically localized prostate cancer

OBJECTIVES

To report the toxicity profile of patients treated with three-dimensional conformal radiation therapy (3D-CRT) or intensity-modulated radiation therapy (IMRT) receiving doses of 82 Gy or more to portions of their prostate.

METHODS

Forty-four patients treated with radiation therapy for prostate cancer between June 1992 and August 1998 at the University of California, San Francisco received a maximal dose within the target volume (Dmax) of 82 Gy or more. Eighteen patients were boosted selectively to a limited portion of their prostate using IMRT, whereas 26 patients were treated with 3D-CRT and had unselected "hot spots" within their prostate. The Radiation Therapy Oncology Group (RTOG) acute and late toxicity scales were used to score gastrointestinal (GI) and genitourinary (GU) morbidity.

RESULTS

Median follow-up and Dmax were 23.1 months (range 10.0 to 84.7) and 84.5 Gy (range 82.0 to 96.7), respectively. Of the patients, 59.1% and 34.1% developed some level of acute GU and GI toxicity, respectively. One patient experienced grade 3 acute GI toxicity. No other grade 3 or greater acute toxicity was observed. The 2-year actuarial rates for freedom from late GI and GU morbidity were 77.1% (95% confidence interval [CI] 60.4% to 87.5%) and 79.5% (95% CI 62.7% to 89.3%), respectively. Although no grade 3 or greater late GU morbidity has been observed to date, 3 patients experienced grade 3 late GI morbidity. However, these cases involved rectal bleeding and were effectively managed with laser coagulation/fulguration.

CONCLUSIONS

Doses of 82 Gy or more to a portion of the prostate gland can be tolerated with acceptable morbidity. This observation supports the continued investigation of IMRT as a means for improving disease control in prostate cancer.

Preliminary results of a randomized radiotherapy dose-escalation study comparing 70 Gy with 78 Gy for prostate cancer

PURPOSE

To determine the effect of radiotherapy dose on prostate cancer patient outcome and biopsy positivity in a phase III trial.

PATIENTS AND METHODS

A total of 305 stage T1 through T3 patients were randomized to receive 70 Gy or 78 Gy of external-beam radiotherapy between 1993 and 1998. Of these, 301 were assessable; stratification was based on pretreatment prostate-specific antigen level (PSA). Dose was prescribed to the isocenter at 2 Gy per fraction. All patients underwent planning pelvic computed tomography scan to confirm prostate position. Treatment failure was defined as an increasing PSA on three consecutive follow-up visits or the initiation of salvage treatment. Median follow-up was 40 months.

RESULTS

One hundred fifty patients were randomized to the 70-Gy arm and 151 to the 78-Gy arm. The difference in freedom from biochemical and/or disease failure (FFF) rates of 69% and 79% for the 70-Gy and 78-Gy groups, respectively, at 5 years was marginally significant (log-rank P: =.058). Multiple-covariate Cox proportional hazards regression showed that the study randomization was an independent correlate of FFF, along with pretreatment PSA, Gleason score, and stage. The patients who benefited most from the 8-Gy dose escalation were those with a pretreatment PSA of more than 10 ng/mL; 5-year FFF rates were 48% and 75% (P: =.011) for the 70-Gy and 78-Gy arms, respectively. There was no difference between the arms ( approximately 80% 5-year FFF) when the pretreatment PSA was < or = 10 ng/mL.

CONCLUSION

A modest dose increase of 8 Gy using conformal radiotherapy resulted in a substantial improvement in prostate cancer FFF rates for patients with a pretreatment PSA of more than 10 ng/mL. These findings document that local persistence of prostate cancer in intermediate- to high-risk patients is a major problem when doses of 70 Gy or less are used.

Salvage radiotherapy for prostate cancer recurrence after cryosurgical ablation

OBJECTIVES

To retrospectively determine the outcome of patients treated with salvage three-dimensional conformal radiotherapy (RT) for prostate cancer recurrence after cryosurgical ablation of the prostate (CSAP). Biochemical control rates and morbidity were analyzed.

METHODS

Between January 1990 and November 1999, a total of 49 patients initially treated with CSAP were later irradiated because of a rising prostate-specific antigen (PSA) level and/or a positive biopsy at Allegheny General Hospital. The clinical stage before cryosurgery was T1c in 7 patients; T2a in 7 patients; T2b in 10 patients; T3 in 17 patients; and T4 and/or N1 in 8 patients. The Gleason score was 6 or lower in 29 patients, 7 in 11 patients, and 8 or higher in 9 patients. The mean pre-CSAP PSA level was 15.7 ng/mL (range 2.4 to 45). One patient had a PSA level less than 4 ng/mL, 16 had a PSA level of 4 to 10 ng/mL, 21 had a PSA level of 10 to 20 ng/mL, and 11 had a PSA level greater than 20 ng/mL. Before the start of RT, a complete restaging workup was performed and was negative for distant metastatic disease in all 49 patients. The mean interval to recurrence after CSAP was 19 months (range 3 to 78). The mean RT dose to the planning target volume was 62.9 Gy (range 50.4 to 68.4).

RESULTS

The mean pre-RT PSA level was 2.4 ng/mL (range 0.1 to 7.4). After RT, the mean nadir PSA level was 0.4 ng/mL (range 0 to 4.2). The mean time to PSA nadir was 5.8 months (range 1 to 15). In 42 patients, the PSA nadir was less than 1.0 ng/mL, in 5 patients the PSA nadir was greater than 1 ng/mL, and in 2 patients the PSA level remained stable. With a median follow-up time of 32 months (range 12 to 85), the overall biochemical control rate was 61%. The mean time to biochemical failure was 14.5 months (range 1 to 47). Of 30 patients with a pre-RT PSA level of 2.5 ng/mL or less, the disease of 22 (73%) was controlled compared with only 8 (42%) of 19 with a pre-RT PSA level greater than 2.5 ng/mL (P = 0.040). Biochemical control occurred in 18 (69%) of 26 patients with a dose of 64 Gy or greater compared with only 12 (52%) of 23 patients with a dose of less than 64 Gy (P = 0.024). The disease of 20 (70%) of 29 patients with a Gleason score of 6 or lower was controlled versus 10 (50%) of 20 patients with a Gleason score of 7 or greater (P = 0.064). Only 2 patients developed subacute morbidity (proctitis and a urethral stricture). All complications resolved with conservative measures.

CONCLUSIONS

Salvage RT for prostate cancer recurrence after CSAP appears feasible. Our preliminary experience revealed that post-CSAP RT in patients with prostate cancer appears to effectively diminish the post-RT PSA level to a nadir of 1.0 ng/mL or less in most patients. The pre-RT PSA level and radiation dose may be important predictors of biochemical control in the salvage setting. RT as described was associated with minimal toxicity to the gastrointestinal/genitourinary systems. Additional prospective randomized studies are necessary to better assess the role of RT in the treatment of these patients.

Overall survival after prostate-specific-antigen-detected recurrence following conformal radiation therapy

PURPOSE

To study the significance, in terms of overall and cause-specific survival, of biochemical failure after conformal external-beam radiation therapy (RT) for prostate cancer.

METHODS AND MATERIALS

Of the 1844 patients in the Radiation Oncology prostate cancer database, 718 were deemed eligible. Patients excluded were those with N1 or M1 disease, those treated after radical prostatectomy, those who received hormone therapy before radiation therapy, and those who died, failed clinically, or had no PSA response in the first 6 months after RT. Patients included were required to have a minimum of 2 post-RT PSAs separated by at least 1 week. Biochemical relapse was defined as 3 consecutive PSA rises. This resulted in 154 patients with biochemical failure. Survival was calculated from the third PSA elevation. The rate of rise of PSA was calculated by fitting a regression line to the four rising PSAs on a ln PSA vs. time plot.

RESULTS

There were 41 deaths among the 154 patients with failure in 23 of the 41 due to prostate cancer. The overall survival after failure was 58% at 5 years, while the cause-specific failure was 73% at 5 years. Among the 154 failures, several factors were evaluated for an association with overall survival: age at failure, pre-RT PSA, PSA at second rise, PSA nadir, time from RT to failure, time to nadir, Gleason score, T-stage, and rate of rise, both from the nadir and from the beginning of the rise. None of these factors were significantly associated with an increased risk of death. As expected, the group of patients with biochemical failure have significantly worse prognostic factors than those without biochemical failure: median pre-RT PSA 15.9 vs. 9.0 (p < 0.001), and Gleason score of 7 or greater for 48% of subjects vs. 40% (p = 0.1). Relative PSA rise and slope of ln PSA vs. time were associated with cause-specific mortality (p < 0.001 and p = 0.007, respectively).

CONCLUSION

Overall survival after conformal radiotherapy for prostate cancer remains high 5 years after biochemical failure. This high survival rate occurs even though the group of patients with biochemical failure has worse than average adverse preradiation prognostic factors. Thus, although biochemical failure can identify patients who have recurrent disease after RT, the ultimate relationship between this endpoint and death remains to be better defined.

A prospective comparison of three systems of patient immobilization for prostate radiotherapy

PURPOSE

The study compared the setup reliability of 3 patient immobilization systems, a rubber leg cushion, the alpha cradle, and the thermoplastic Hipfix device, in 77 patients with cT1-T3, N0, M0 prostate cancer receiving conformal radiotherapy.

METHODS AND MATERIALS

Port films were analyzed and compared to simulation films to estimate the setup errors in the three coordinate axes (anterior-posterior, cranial-caudal, medial-lateral). A total vector error was calculated from these shifts.

RESULTS

The Hipfix was found significantly superior to the other two devices in reducing mean setup errors in all axes (p < 0.005). The average field-positioning error with the Hipfix ranged from 1.9 mm to 2.6 mm for all axes, whereas the deviation for the other two systems ranged from 2.7 to 3. 4 mm. Errors greater than 10 mm were virtually eliminated with the Hipfix system. There was a reduction in the mean total vector error in the alpha cradle and Hipfix patient cohorts over time, reflecting improved efficacy as a result of experience.

CONCLUSION

There was a significant difference in the performance of each immobilization device. The Hipfix was consistently more reliable in reducing setup errors than the other devices.

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.