125iodine reimplantation for locally progressive prostatic carcinoma

Efficacy and toxicity outcomes for patients treated with focal salvage high dose rate brachytherapy for locally recurrent prostate cancer

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Local recurrence of prostate cancer may be treated with salvage therapies.

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Focal salvage high dose rate brachytherapy provides good biochemical control.

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Severe genitourinary and gastrointestinal toxicities are low.

Introduction

Isolated local recurrence of prostate cancer following primary radiotherapy or brachytherapy may be treated with focal salvage high dose rate brachytherapy, although there remains an absence of high quality evidence to support this approach.

Methods

Men with prostate cancer treated consecutively between 2015 and 2018 using 19 Gy in a single fraction high dose rate brachytherapy (HDR) for locally recurrent prostate cancer were identified from an institutional database. Univariable analysis was performed to evaluate the relationship between patient, disease and treatment factors with biochemical progression free survival (bPFS).

Results

43 patients were eligible for evaluation. Median follow up duration was 26 months (range 1–60). Median bPFS was 35 months (95% confidence interval 25.6–44.4). Kaplan-Meier estimates for bPFS at 1, 2 and 3 years post salvage were 95.2%, 70.6% and 41.8% respectively. On univariable Cox regression analysis, only nadir PSA was significantly associated with bPFS although the majority of patients were also treated with androgen deprivation therapy. Only one late grade 3 genitourinary toxicity was observed.

Conclusion

Focal salvage HDR brachytherapy may provide good biochemical control with a low risk of severe toxicity. Further evaluation within clinical trials are needed to establish its role in the management of locally recurrent prostate cancer.

Focal salvage low-dose-rate brachytherapy for recurrent prostate cancer based on magnetic resonance imaging/transrectal ultrasound fusion biopsy technique

OBJECTIVE

To examine the effect of permanent salvage brachytherapy in prostate cancer patients suffering recurrence after three-dimensional conformal external beam radiotherapy.

METHODS

The ultra-focal (target lesion alone), hemi-lobe (within a hemi-lobe) or focused whole-gland (focusing on the lesion, but extending into the whole gland) pattern was selected based on the Gleason score for the targeted biopsy, the numbers of positive cores in the targeted and systematic biopsies, and the locations of the positive cores. Novel dosimetry criteria derived from three-dimensional cancer mapping, which was based on targeted magnetic resonance imaging/transrectal ultrasound fusion biopsies, were used in these cases.

RESULTS

Permanent salvage brachytherapy was carried out in 13 patients who suffered prostate-specific antigen failure (prostate-specific antigen 2.1-6.8 ng/mL; age range 57-75 years; Gleason score ≤7 [n = 10], Gleason score ≥8 [n = 2] and Gleason score not available [n = 1]) since 2012. The targeted biopsy showed a single focus in three patients. The ultra-focal, hemi-lobe and focused whole-gland patterns were chosen in three, five and five patients, respectively. During the follow-up period (median duration 48 months), prostate-specific antigen failure occurred in zero of three, one of five and three of five of the patients treated with the ultra-focal, hemi-lobe and focused whole-gland patterns, respectively. The 4-year biochemical recurrence-free survival rate was 74%. No grade 3-4 adverse intestinal or urological events occurred.

CONCLUSIONS

Targeted fusion biopsy-based three-dimensional cancer mapping should be used for permanent salvage brachytherapy treatment planning to reduce the incidence of treatment-related adverse events while maintaining good oncological outcomes.

Prostate cancer as a paradigm of multidisciplinary approach? Highlights from the Italian young radiation oncologist meeting

Aims and background

The diagnostic and therapeutic approach to prostate cancer has evolved rapidly in last decades. Young professionals need an update about these recent developments in order to improve the care of patients treated in their daily clinical practice.

Methods

On May 18, 2013, AIRO Giovani (the young section of the Italian Association of Radiation Oncology) organized a multidisciplinary meeting involving, as speakers, several young physicians from many parts of Italy actively involved in the diagnostic and therapeutic approach to prostate cancer. The meeting was specifically addressed to young physicians (radio-oncologists, urologists, medical oncologists) and presented the state-of-the-art of the diagnostic/therapeutic approach based on the latest evidence on the issue. Highlights of the congress are summarized and presented in this report.

Results

The large participation in the meeting (more than 120 participants were present) confirmed the interest of young radiation oncologists in improving their skills in prostate cancer management. The contributions of the speakers confirmed the need for regular updates, considering the promising results of recently published studies and the many new ongoing trials, on the diagnostic and therapeutic approaches to prostate cancer.

Conclusions

Multidisciplinary meetings are helpful to improve the skills of young professionals.

Salvage brachytherapy for locally recurrent prostate cancer after external beam radiotherapy

External beam radiotherapy (EBRT) is a standard treatment for prostate cancer. Despite the development of novel radiotherapy techniques such as intensity-modulated conformal radiotherapy, the risk of local recurrence after EBRT has not been obviated. Various local treatment options (including salvage prostatectomy, brachytherapy, cryotherapy, and high-intensity focused ultrasound [HIFU]) have been employed in cases of local recurrence after primary EBRT. Brachytherapy is the first-line treatment for low-risk and selected intermediate-risk prostate tumors. However, few studies have examined the use of brachytherapy to treat post-EBRT recurrent prostate cancer. The purpose of this paper is to analyze the current state of our knowledge about the effects of salvage brachytherapy in patients who develop locally recurrent prostate cancer after primary EBRT. This article also introduces our novel permanent brachytherapy salvage method.

Salvage Brachytherapy for Biochemically Recurrent Prostate Cancer following Primary Brachytherapy

Purpose. In this study, we evaluated our experience with salvage brachytherapy after discovery of biochemical recurrence after a prior brachytherapy procedure. Methods and Materials. From 2001 through 2012 twenty-one patients treated by brachytherapy within University of Kentucky or from outside centers developed biochemical failure and had no evidence of metastases. Computed tomography (CT) scans were evaluated; patients who had an underseeded portion of their prostate were considered for reimplantation. Results. The majority of the patients in this study (61.9%) were low risk and median presalvage PSA was 3.49 (range 17.41-1.68). Mean follow-up was 61 months. At last follow-up after reseeding, 11/21 (52.4%) were free of biochemical recurrence. There was a trend towards decreased freedom from biochemical recurrence in low risk patients (p = 0.12). International Prostate Symptom Scores (IPSS) increased at 3-month follow-up visits but decreased and were equivalent to baseline scores at 18 months. Conclusions. Salvage brachytherapy after primary brachytherapy is possible; however, in our experience the side-effect profile after the second brachytherapy procedure was higher than after the first brachytherapy procedure. In this cohort of patients we demonstrate that approximately 50% oncologic control, low risk patients appear to have better outcomes than others.

Salvage low-dose-rate (125)I partial prostate brachytherapy after dose-escalated external beam radiotherapy

Purpose

To report outcomes on 5 patients treated with salvage partial low-dose-rate (LDR) 125-iodine (¹²⁵I) permanent prostate seed brachytherapy (BT) for biopsy-proven locally persistent prostate cancer, following failure of dose-escalated external beam radiotherapy (EBRT).

Material and methods

A retrospective review of the Fox Chase Cancer Center prostate cancer database identified five patients treated with salvage partial LDR ¹²⁵I seed implant for locally persistent disease following dose-escalated EBRT to 76-84 Gy in 2 Gy per fraction equivalent. All patients had post-EBRT biopsies confirming unilateral locally persistent prostate cancer. Pre-treatment, EBRT and BT details, as well as post-treatment characteristics were documented and assessed.

Results

The median follow-up post-implant was 41 months. All five patients exhibited low acute genitourinary and gastrointestinal toxicities. Increased erectile dysfunction was noted in three patients. There were no biochemical failures following salvage LDR ¹²⁵I seed BT to date, with a median post-salvage PSA of 0.4 ng/mL.

Conclusions

In carefully selected patients with local persistence of disease, partial LDR ¹²⁵I permanent prostate seed implant appears to be a feasible option for salvage local therapy with an acceptable toxicity profile. Further study is needed to determine long-term results of this approach.

Retreatment for prostate cancer with stereotactic body radiation therapy (SBRT): Feasible or foolhardy?

The most popular therapeutic option in the management of radio-recurrent prostatic carcinoma is represented by the androgen deprivation therapy, that however should be considered only palliative and hampered by potential adverse effects of testosterone suppression. Local therapies such as surgery, cryoablation or brachytherapy might be curative choices for patients in good conditions and with a long-life expectancy, but at cost of significant risk of failure and severe toxicity. The administration of stereotactic body radiation therapy (SBRT) in this setting have come about because of tremendous technologic advances in image guidance and treatment delivery techniques that enable the delivery of large doses to tumor with reduced margins and high gradients outside the target, thereby reducing the volume of rectum which already received significant doses from primary radiotherapy. So far, very modest data are available to support its employment. Rationale, clinical experience, and challenges are herein reviewed and discussed.

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.

Current salvage methods for recurrent prostate cancer after failure of primary radiotherapy

We reviewed the current salvage methods for patients with local recurrent prostate cancer after primary radiotherapy (RT), using a search of relevant Medline/PubMed articles published from 1982 to 2008, with the following search terms: 'radiorecurrent prostate cancer, local salvage treatment, salvage radical prostatectomy (RP), salvage cryoablation, salvage brachytherapy, salvage high-intensity focused ultrasound (HIFU)', and permutations of the above. Only articles written in English were included. The objectives of this review were to analyse the eligibility criteria for careful selection of appropriate patients and to evaluate the oncological results and complications for each method. There are four whole-gland re-treatment options (salvage RP, salvage cryoablation, salvage brachytherapy, salvage HIFU) for RT failure, although others might be in development or investigations. Salvage RP has the longest follow-up with acceptable oncological results, but it is a challenging technique with a high complication rate. Salvage cryoablation is a feasible option, especially using third-generation technology, whereby the average biochemical disease-free survival rate is 50-70% and there are fewer occurrences of severe complications such as recto-urethral fistula. Salvage brachytherapy, with short-term cancer control, is comparable to other salvage methods but depends on cumulative dosage limitation to target tissues. HIFU is a relatively recent option in the salvage setting. Both salvage brachytherapy and HIFU require more detailed studies with intermediate and long-term follow-up. As these are not prospective, randomized studies and the definitions of biochemical failure varied, there are limited comparisons among these different salvage methods, including efficacy. In the focal therapy salvage setting, the increased use of thermoablative methods for eligible patients might contribute to reducing complications and maintaining quality of life. The problem to effectively salvage patients with locally recurrent disease after RT is the lack of diagnostic examinations with sufficient sensitivity and specificity to detect local recurrence at an early curable stage. Therefore, a more strict definition of biochemical failure, improved imaging techniques, and accurate specimen mapping are needed as diagnostic tools. Furthermore, universal selection criteria and an integrated definition of biochemical failure for all salvage methods are required to determine which provides the best oncological efficacy and least comorbidity.

Patient selection, cancer control, and complications after salvage local therapy for postradiation prostate-specific antigen failure

Among men who experience prostate-specific antigen (PSA) failure after external beam radiation or brachytherapy (RT), many will harbor occult micrometastases; however, a significant minority will have a true local-only failure and, thus, potentially may benefit from a salvage local therapy. Those most likely to have a local-only failure initially have low-risk disease (PSA < 10 ng/mL, Gleason score < or =6, clinical T1c or T2a tumor status), pretreatment PSA velocity < 2.0 ng/mL per year at the time of initial presentation, interval to PSA failure > 3 years, PSA doubling time > 12 months, negative bone scan and pelvic imaging, and positive rebiopsy. In addition, men with presalvage PSA levels > 10 ng/mL, presalvage T3/T4 disease, or presalvage Gleason scores > or =7 on a rebiopsy sample without significant RT effects are unlikely to be cured by salvage local therapy. Based on a review of all series of post-RT salvage prostatectomy, cryosurgery, and brachytherapy published in English since 1990, morbidity can be substantial. Although urinary incontinence appeared to be greater after salvage prostatectomy (41%) or cryosurgery (36%) than after brachytherapy (6%), patients who received salvage brachytherapy faced a 17% risk of grade 3 or 4 genitourinary complications and a fistula risk that averaged 3.4% across all series. From this review, the authors concluded that prospective randomized studies are needed to determine the relative efficacy of the 3 major local salvage modalities and that additional research is needed to identify factors associated with an increased risk of significant complications to improve patient selection and to augment the benefit/risk ratio associated with attempts to cure local-only recurrences after radiation therapy.

Magnetic resonance image-guided salvage brachytherapy after radiation in select men who initially presented with favorable-risk prostate cancer

BACKGROUND

The authors prospectively evaluated the late gastrointestinal (GI) and genitourinary (GU) toxicity and prostate-specific antigen (PSA) control of magnetic resonance imaging (MRI)-guided brachytherapy used as salvage for radiation therapy (RT) failure.

METHODS

From October 2000 to October 2005, 25 men with a rising PSA level and biopsy-proven, intraprostatic cancer at least 2 years after initial RT (external beam in 13 men and brachytherapy in 12 men) who had favorable clinical features (Gleason score < or =7, PSA < 10 ng/mL, negative pelvic and bone imaging studies), received MRI-guided salvage brachytherapy to a minimum peripheral dose of 137 gray on a phase 1/2 protocol. Estimates of toxicity and cancer control were calculated using the Kaplan-Meier method.

RESULTS

The median follow-up was 47 months. The 4-year estimate of grade 3 or 4 GI or GU toxicity was 30%, and 13% of patients required a colostomy and/or urostomy to repair a fistula. An interval < 4.5 years between RT courses was associated with both outcomes with a hazard ratio of 12 (95% confidence interval [95% CI], 1.4-100; P = .02) for grade 3 or 4 toxicity and 25 (95% CI, 1.1-529; P = .04) for colostomy and/or urostomy. PSA control (nadir +2 definition) was 70% at 4 years.

CONCLUSIONS

The current results indicated that MRI-guided salvage brachytherapy in men who are selected based on presenting characteristics and post-failure PSA kinetics can achieve high PSA control rates, although complications requiring surgical intervention may occur in 10% to 15% of patients. Prospective randomized studies are needed to characterize the relative cancer control and toxicity after all forms of salvage local therapy.

Management of prostate cancer recurrences after radiation therapy-brachytherapy as a salvage option

Depending on initial prognostic factors, an estimated 10%-60% of men who undergo definitive radiation therapy for prostate cancer may experience a biochemical recurrence. Even though hormonal therapy is standard for metastatic recurrences, no consensus exists on optimal salvage therapy for those recurrences thought confined to the prostate. Salvage treatment options for these local recurrences have historically been limited to salvage prostatectomy, hormonal therapy, or cryotherapy. Salvage prostate brachytherapy, however, uses a widely available technique and may provide another option for attaining disease control in patients with localized failures, although only about 110 cases have been reported in the literature. In this report, the authors have described their own series of salvage brachytherapy cases as well as presented a review of other such series reported in the literature. In addition, the authors included a comprehensive review of published experiences with surgery and cryotherapy as salvage options. It appears that salvage brachytherapy, when combined with careful patient selection, is at least as effective as other salvage options with comparable or potentially fewer treatment-related side effects.

When Prostate Brachytherapy Fails: A Case Report and Discussion

For appropriately selected brachytherapy patients, prostate-specific antigen failure is uncommon. Our patient experienced biochemical failure after 125I brachytherapy treatment for low-risk prostate adenocarcinoma. We suggest neoadjuvant/adjuvant hormonal therapy combined with pelvic external-beam radiation therapy as a reasonable salvage treatment. At the 2-year follow-up, he is apparently doing well. With limited data available, salvage management for this situation is presently investigational.

The impact of technological advances on the evolution of 3D conformal brachytherapy for early prostate cancer

Permanent implantation of I-125 and Pd-103 seeds is one of the widely used treatment options for the early stage prostate cancer with minimum normal tissue complications and long-term local control of the tumor. This is possible because of several technological advances made in the past decade to better understand the procedural aspects of implantations with the desired clinical outcome and with acceptable morbidities. In addition, with the widespread use of PSA testing, more widely disseminated information about prostate cancer and increased patient awareness, over 70% of patients are diagnosed early with localized disease and therefore are candidates for definitive local therapy. Delineation of soft tissue structures including the prostate, rectum, urethra and bladder has become more accurate with the use of imaging modalities including Ultrasound and MRI, with or without the CT. A re-evaluation of the dosimetric parameters of the radioactive sources has lead to a more precise estimate of the dose delivered to the prostate and the associated critical normal structures. Technological improvements in the post implant dosimetry have helped to understand the factors, which makes an implant a "good implant" or a "poor implant". Intraoperative treatment planning with on line dosimetry is emerging as one of the best approaches for prostate brachytherapy. In addition, better software is now available producing dose-volume histograms with 3D target and normal tissue reconstruction. The combination of seed implant followed by IMRT would provide scope for differentially boosting the regions under-dosed because of uncontrollable and unexpected reasons during the implant and unsuspected micro extensions of the tumor.

Salvage reimplantation in patient with local recurrent prostate carcinoma after brachytherapy with three dimensional computed tomography-guided permanent pararectal implant

Thirty-one [31] patients with local recurrent or residual adenocarcinoma of the prostate, with no evidence of distant metastases, were treated with second permanent implant using a stereotactic three dimensional system and posterior pararectal CT-guided method. All patients had extensive under local anesthesia or IV sedation pararectal CT-guided biopsy of the prostate and seminal vesicles. All patients except one had 3 month neoadjuvant androgen ablation prior to salvage reimplantation. Twenty [20] of these patients had local recurrence in the prostate and eleven [11] patients had seminal vesicle invasion which was not diagnosed nor treated with the initial brachytherapy. In addition, the patients had PSA failure or local palpable disease, "cold spots" with CT imaging or areas of dosage less than 80% of the prescribed dose with DVH (dose volume histogram). Initial prescribed dose was 120 Gy with (103)Pd loose seeds in 26 patients and 144 Gy with (125)I loose seeds in 5 patients. For the reimplant the dosage in the recurrent site was 100-144 Gy with (125)I seeds in strand in 24 patients (77%) and 100-120 Gy with (103)Pd loose seeds in 7 patients (23%). The preference of (125)I seeds in the second treatment was because only (125)I in strand was available at the time of the reimplant. Eleven [11] patients had second implant twelve to twenty-four months after the initial implant and 20 patients had after twenty-five to eighty-seven months and median follow-up was thirty months. A high level of biochemical control (87%) was achieved in all of these patients who are recognized as high risk due to local recurrence. Four [4] patients experienced grade 2 or 3 GI or GU complications and two [2] patients experienced grade 4 GI complications. Patients with local recurrent prostate cancer following initial brachytherapy including those with seminal vesicle invasion can be successfully treated with pararectal stereotactic CT-guided reimplantation. Assessment of seminal vesicle status is an essential part of staging for local recurrence.

PSA progression following radical prostatectomy and radiation therapy: new standards in the new Millennium

Prostate-specific antigen (PSA) progression following radical treatments of clinically localized prostate cancer is a common problem facing both the patient and the urologist. Not all patients with relapsing disease have an equal risk of death due to prostate cancer. After surgery, biochemical failure can be defined as persisting detectable levels of PSA after radical prostatectomy or a PSA rise after a period of normalization. On the other hand, definitions of PSA progression after radiation therapy vary and no clear consensus can be found. This review of the recent international literature updates the knowledge about the diagnostic procedures used in relapsing patients. Predictors of progression are precised leading to a better patient selection, based on currently available tables and nomograms. Indeed, identification of high risk patients may allow a more appropriate treatment decision. After radical treatment, the analysis of time to recurrence, PSA doubling time, PSA kinetics combined to modern imaging techniques such as 111In capromab penditide scan may allow a better identification of the recurrence site. Thus, an optimal treatment strategy may be envisaged such as local irradiation, salvage surgery, hormone therapy or combinations for which indications and results are provided. Alternative options such as cryotherapy still need further investigation. At last, the use of artificial neural networks will certainly enhance the selection of patients submitted to radical treatments as well as the selection of relapsing patients to allow a more appropriate adjuvant therapy.

[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.

Permanent brachytherapy as salvage treatment for recurrent prostate cancer

OBJECTIVES

To determine the prostate-specific antigen (PSA)-based freedom from second failure, survival, and morbidity of permanent brachytherapy as salvage treatment for men for whom primary external beam irradiation of prostate cancer failed.

METHODS

A retrospective review was performed on 17 consecutive men seen and treated with permanent brachytherapy for recurrent adenocarcinoma of the prostate from February 1989 to May 1994. Patients had been treated with a median of 63.3 Gy and presented with progressive local disease 23 to 146 months later (median 54). After a staging evaluation documenting no distant disease, all received permanent implantation of iodine-125 for 120 Gy (15 patients) or palladium-103 for 90 Gy (2 patients) using a transperineal ultrasound-guided technique. All doses were calculated before TG-43. Progression after brachytherapy was defined according to the ASTRO Consensus Conference definition. All results are reported as Kaplan-Meier actuarial 5-year results.

RESULTS

The 5-year actuarial freedom from second relapse was 53%. Both PSA and Gleason score appear to be prognostic factors, although both failed to reach statistical significance. Patients with a PSA 10 ng/mL or less at the time of salvage therapy had a freedom from second relapse rate of 67% compared with 25% for men with a PSA greater than 10 ng/mL (P = 0. 15). Those with low-grade tumor at the time of salvage therapy had an 83% freedom from second relapse rate compared with 30% for those with high-grade cancer (P = 0. 12). With 93% alive at 5 years, no significant difference was seen in survival on the basis of these prognostic groups. Acute and transient toxicity were readily managed and indistinguishable from that reported for previously unirradiated patients. Long-term complications were limited to a 24% risk of incontinence at 5 years.

CONCLUSIONS

Ultrasound-guided transperineal brachytherapy is an effective second-line therapy for patients for whom external beam irradiation has failed. Early intervention may be valuable when the PSA is less than 10 ng/mL. The risk of incontinence is significant, and patients must be individually counseled.

American Brachytherapy Society (ABS) recommendations for transperineal permanent brachytherapy of prostate cancer

PURPOSE/OBJECTIVE

To develop and disseminate the American Brachytherapy Society (ABS) recommendations for the clinical quality assurance and guidelines of permanent transperineal prostate brachytherapy with 125I or 103Pd.

METHODS AND MATERIALS

The ABS formed a committee of experts in prostate brachytherapy to develop consensus guidelines through a critical analysis of published data supplemented by their clinical experience. The recommendations of the panels were reviewed and approved by the Board of Directors of the ABS.

RESULTS

Patients with high probability of organ-confined disease are appropriately treated with brachytherapy alone. Brachytherapy candidates with a significant risk of extraprostatic extension should be treated with supplemental external beam radiation therapy (EBRT). Patient selection guidelines were developed. Dosimetric planning of the implant should be carried out for all patients before seed insertion. A modified peripheral loading is preferred. The AAPM TG-43 recommendations requiring a change in prescription dose for 125I sources should be universally implemented. The recommended prescription doses for monotherapy are 145 Gy for 125I and 115-120 Gy for 103Pd. The corresponding boost doses (after 40-50 Gy EBRT) are 100-110 Gy and 80-90 Gy, respectively. Clinical evidence to guide selection of radionuclide (103Pd or 125I) is lacking. Post implant dosimetry and evaluation must be performed on all patients. It is suggested that the dose that covers 90% (D90) and 100% (D100) of the prostate volume and the percentage of the prostate volume receiving the prescribed dose (V100) be obtained from a dose-volume histogram (DVH) and reported.

CONCLUSION

Guidelines for appropriate patient selection, dose reporting, and improved quality of permanent prostate brachytherapy are presented. These broad recommendations are intended to be technical and advisory in nature, but the ultimate responsibility for the medical decisions rests with the treating physician. This is a constantly evolving field, and the recommendations are subject to modifications as new data becomes available.

The management of PSA failure after radical radiotherapy for localized prostate cancer

An asymptomatic rising serum prostate-specific antigen (PSA) level is the most common form of failure after radical radiotherapy for localized prostate cancer, but there is no consensus as to how it should be managed. This review addresses the following three questions concerning men with PSA failure after radiotherapy: (i) what is the course of the disease without further intervention?; (ii) what is the role of radical treatment, such as salvage prostatectomy?; and (iii) should androgen deprivation be started immediately or should it be delayed until clinical progression occurs? An algorithm for the management of PSA failure after radical radiotherapy for localized prostate cancer is proposed.

PSA for outcome prediction and posttreatment evaluation following radiation for prostate cancer: do we know how to use it?

Pretreatment prostate-specific antigen (PSA) has been shown to be a powerful predictor of expected outcome after radiation for prostate cancer. Additional measures such as recursive partitioning analysis and PSA Cancer Volume calculations are further refining this useful tool to provide the greatest degree of prognostic information. The post-treatment PSA level is also being used as a means to assess therapeutic efficacy rapidly and objectively. Although no single PSA value has been shown to equate to long-term clinical tumor control consistently, consensus has been reached regarding the value of a rising PSA level as an early surrogate for tumor recurrence. Since the first introduction of PSA as a tumor marker, we have become much more comfortable with what it means, the ways it can help us, and how to use it.

Should asymptomatic progression following definitive local treatment for prostate cancer be treated?

Asymptomatic progression following definitive therapy for prostate cancer can take the form of a detectable prostate-specific antigen (PSA) or local recurrence following radical prostatectomy or a rising PSA or palpable recurrence following radiotherapy. Options for treatment include hormonal therapy, radiotherapy, salvage surgery, and experimental therapies. Although such forms of treatment have known effects on intermediate endpoints, such as reduction of PSA, the overall effect on survival and quality of life is uncertain.

Analysis of biopsy findings and implant quality following ultrasonically-guided 125I implantation for localised prostatic carcinoma

Transperineal ultrasound-guided 125I implantation was undertaken in 52 patients with localised prostate cancer. After implantation, ultrasound-guided biopsies were taken from the previous malignant areas every 6 months in all patients. The percentage of negative biopsies increased from 22% at 6 months to 50% at 48 months. Implant quality was analysed in 37 patients. The difference between isodose levels encompassing the prostate and the aimed levels of 160 Gy was taken as a measure of implant quality. A good quality implant (< 10% underdosage) was found in 43% of patients, a moderate quality (10-25% underdosage) in 35%, and a poor quality implant (> 25% underdosage) in 22%. A statistically significant correlation was found between the quality of the implant and resulting negative biopsy at the original tumour site. Determination of prostate specific antigen (PSA) was not possible from the beginning of the study but an analysis with biopsy findings, implant quality and prostate volume reduction during follow-up has been performed since 1989. A significant correlation was observed between implant quality and serum PSA, and also between volume reduction and serum PSA.

The clinical significance of a positive post-irradiation prostatic biopsy without metastases

To define the prognostic value of a post-irradiation prostatic biopsy, the outcome of 203 previously irradiated patients who underwent post-treatment biopsy was analyzed. The majority of patients were selected for biopsy based on an abnormal digital rectal exam or elevated prostate specific antigen. Patients with distant metastases found at the time of biopsy were excluded from further analysis. One hundred thirty-nine (139) of these had a positive biopsy and 64 were negative. Those with a positive biopsy tended to present with more locally-advanced (Stage B2/C) tumors (61%) compared to those with negative biopsies (42%). The 10- and 15-year survival and cause-specific survival from the time of initial presentation were similar for both groups. However, those with a negative biopsy had a more favorable survival and cause-specific survival from the time of post-treatment biopsy and were less likely to develop distant metastases than the positive biopsy group. These data suggest that a positive prostatic biopsy is associated with a greater likelihood of subsequent distant relapse and decreased survival following biopsy relative to patients with negative biopsies. Since a positive post-treatment biopsy is more likely among patients presenting with locally-advanced disease, perhaps more aggressive initial therapy (i.e., interstitial boost or hyperthermia) would benefit this subgroup.