Treatment options for localized recurrence of prostate cancer following radiation therapy

Salvage prostate cryoablation after primary interstitial brachytherapy failure: a feasible approach

Salvage treatment for recurrent prostate cancer remains a very difficult and challenging field in urologic oncology. The introduction of minimally invasive surgical procedures such a targeted cryoablation brings some hope with its feasibility and efficacy to become a potentially curable treatment. We present the case of a 75-year-old male with prostate cancer treated primarily by brachytherapy, who developed late locally recurrent disease that was successfully treated with targeted salvage cryoablation.

Role of transrectal ultrasound guided salvage cryosurgery for recurrent prostate carcinoma after radiotherapy

Despite improvements in treatment of localized prostate cancer, local recurrence remains a significant problem. A total of 46 patients with proven local cancer recurrence following external beam radiotherapy entered a prospective clinical trial using ultrasound-guided cryosurgery to ablate the residual prostate gland. Persistent complications included one urethra-rectal fistula, incontinence (2), retention (3), and treatment induced erectile dysfunction (7). Using the PSA definitions for biochemical failure as PSA>or=0.3 ng/ml, the Kaplan-Meier plots showed the incidence of patients to be free of biochemical recurrence at 51 and 44% at 1 and 2 y, respectively. For a PSA>or=1.0, the values at 1 and 2 y were 72 and 58%.

Long-term oncologic results of salvage radical prostatectomy for locally recurrent prostate cancer after radiotherapy

PURPOSE

Salvage radical prostatectomy (RP) may potentially cure patients who have isolated local prostate cancer recurrence after radiotherapy (RT). We report the long-term cancer control associated with salvage RP in a consecutive cohort of patients and identify the variables associated with disease progression and cancer survival.

METHODS AND MATERIALS

A total of 100 consecutive patients underwent salvage RP with curative intent for biopsy-confirmed, locally recurrent, prostate cancer after RT. Disease progression after salvage RP was defined as a prostate-specific antigen (PSA) level of > or =0.2 ng/mL or by initiation of androgen deprivation therapy. Cancer-specific mortality was defined as active clinical disease progression despite castration. Cox regression analysis was used to evaluate these endpoints. The median follow-up from RT was 10 years (range, 3-27 years) and from salvage RP was 5 years (range, 1-20 years).

RESULTS

Overall, the 5-year progression-free probability was 55% (95% confidence interval, 46-64%), and the median progression-free interval was 6.4 years. The preoperative PSA level was the only significant pretreatment predictor of disease progression in the multivariate analysis (p = 0.01). The 5-year progression-free probability for patients with a preoperative PSA level of <4, 4-10, and >10 ng/mL was 86%, 55%, and 37%, respectively. The 10-year and 15-year cancer-specific mortality after salvage RP was 27% and 40%, respectively. The median time from disease progression to cancer-specific death was 10.3 years (95% confidence interval, 7.6-12.9). After multivariate analysis, the preoperative serum PSA level and seminal vesicle or lymph node status correlated independently with disease progression.

CONCLUSIONS

Greater preoperative PSA levels are associated with disease progression and cancer-specific death. Long-term control of locally recurrent prostate cancer after definitive RT is possible when salvage RP is performed early in the course of recurrent disease.

Management of prostate-specific antigen relapse in prostate cancer: a European Consensus

A European Consensus on the management of prostate-specific antigen (PSA) relapse in patients with prostate cancer has been formulated. The key recommendations proposed are that total PSA is the best detection tool for prostate cancer, with free and complexed PSA having a role in the PSA range 1-4 ng/ml. PSA relapse after radical prostatectomy (RP) has been defined as a value of 0.2 ng/ml with one subsequent rise, while the ASTRO definition should be used after radiotherapy. A PSA level of less than 0.4 ng/ml after hormonal therapy can be considered an indicator of a positive response. Continuous assessment using nomograms or artificial neural networks will help to determine whether progression after local therapy is distant or local, which is the basis for treatment decisions. Secondary treatment after local failure of RP should be initiated when PSA levels reach 1.0-1.5 ng/ml and salvage radiotherapy can be considered with or without hormonal therapy. Local failure after radiotherapy can be treated with a choice of high-intensity-focused ultrasound, salvage RP (only in highly selected patients), cryotherapy or external beam radiation. Treatment of distant failure involves hormonal manipulation, the type and the timing of which is based on both physician and patient preferences.

Brachytherapy for prostate cancer

The use of prostate brachytherapy for the treatment of early-stage, low-grade, low-volume carcinoma of the prostate continues to rise. Given the prolonged natural history of these early lesions, treatment failures may take many years or even a decade or more before becoming clinically evident. It is therefore likely that as the brachytherapy data mature, clinicians will be asked to help manage a potentially large cohort of men who have failed this local therapy--a scenario that will provide a number of unique challenges for the treatment of the disease and the management of the lower urinary tract. This article offers a contemporary review and suggestions with regard to the follow-up of patients who have undergone prostate brachytherapy, including low-dose rate permanent implants and high-dose rate temporary implants for the management of localized prostate cancer. In addition, current controversies in defining biochemical failure following radioactive implantation--including important data regarding the "prostate-specific antigen bounce" phenomenon--are discussed. Finally, a comprehensive review of the management of local recurrence following brachytherapy is offered.

Salvage Cryosurgery for Recurrent Prostate Cancer After Radiation Therapy: A Seven-Year Follow-up

Cryosurgery of the prostate presents as an efficient therapy following failed radiation therapy. We report on a 7-year retrospective analysis evaluating the morbidity adn biochemical disease-free survival(bDFS) of this therapy. Between 1993 and 2001, 59 patients who had been previously treated with radiation therapy and had rising serum prostate-specific antigen(PSA) values underwent salvage cryoablation of the prostate for localized, histologically proven, recurrent prostate cancer. Serial serum PSA testing was performed, and biopsies were taken at 6, 12, and 24 months, and again at 5 years, and any time the PSA rose above 0.5 ng/mL. Patients were stratified along clinical parameters. The combined postsalvage bDFS rate using a PSA cutoff of 0.5 ng/mL was 59% and 69% with a 1.0 ng/mL PSA cut off. Using a PSA threshold of 0.5 ng/mL as evidence of biochemical recurrence, 61%, 62%, and 50% of patients with <4 ng/mL, 4-10 ng/mL, and > 10 ng/mL PSA, respectively, remain biochemically relapse free at 7 years. A threshold of 1.0 ng/mL yielded a disease-free status of 78%, 74%, and 46% respectively. Patients biopsies showed no evidence of residual or recurrent disease. Improved survival rates and no known latent complications indicate cryosurgery is a promising form of treatment for radiation-resistant prostate cancer. This 7-year analysis shows a promising validation of cryosurgery as an efficacious treatment modality for locally confined T1-T3 prostate cancer following primary radiation therapy failure.

Selecting a secondary treatment

There is compelling evidence that early hormonal therapy prolongs life in many stages of prostate cancer. Large-scale trials to answer this question have not yet been conducted in surgically treated patients or in patients with PSA-only relapse. Thus, many physicians and patients use early hormone therapy in PSA-only relapse. Many unique new agents are being tested in this population and may offer benefits. Patients and physicians are encouraged to participate in such trials, with hormone therapy reserved for subsequent use. Following failure of primary hormone therapy, a standard algorithm of care exists: antiandrogen withdrawal, use of alternative or first-line anti-androgens. ketoconazole. and chemotherapy. At each interval, clinical trials should be offered since none of these maneuvers are proven to prolong life.

Photodynamic therapy for prostate cancer recurrence after radiotherapy: a phase I study

PURPOSE

Photodynamic therapy, using a photosensitizing drug activated by red light, can destroy localized areas of cancer with safe healing and without the cumulative toxicity associated with ionizing radiation. We used photodynamic therapy in a phase I-II study to treat patients with locally recurrent prostate cancer after radiotherapy.

MATERIALS AND METHODS

Patients with an increasing prostate specific antigen (PSA) and biopsy proven local recurrence after radiotherapy were offered photodynamic therapy. Three days after intravenous administration of the photosensitizer meso-tetrahydroxyphenyl chlorin, light was applied using optical fibers inserted percutaneously through perineal needles positioned in the prostate with imaging guidance. Patients were followed with PSA measurements, prostate biopsies, computerized tomography or magnetic resonance imaging and questionnaires on urinary and sexual function.

RESULTS

Photodynamic therapy was given to 14 men using high light doses in 13. Treatment was well tolerated. PSA decreased in 9 patients (to undetectable levels in 2) and 5 had no viable tumor on posttreatment biopsies. After photodynamic therapy, contrast enhanced computerized tomography or magnetic resonance imaging showed necrosis involving up to 91% of the prostate cross section. In 4 men stress incontinence developed (troublesome in 2 and mild in 2) which is slowly improving. Sexual potency was impaired in 4 of the 7 men able to have intercourse before photodynamic therapy, which did not improve. There were no rectal complications directly related to photodynamic therapy, but in 1 patient a urethrorectal fistula developed following an ill-advised rectal biopsy 1 month after therapy.

CONCLUSIONS

Photodynamic therapy is a new option that could be suitable for organ confined prostate cancer recurrence after radiotherapy. With more precise light dosimetry, it may be possible to destroy essentially all glandular tissue within the prostate with few complications. These results suggest that photodynamic therapy merits further investigation.

Salvage radical prostatectomy

Although technically challenging, salvage prostatectomy for radiorecurrent prostate cancer is an effective option in carefully selected patients and offers the best chance for cure and long-term survival. Alternatively, cystoprostatectomy may be indicated in some patients who have a small capacity fibrotic bladder or intractable voiding symptoms related to radiation cystitis. Good long-term results can be expected in this patient group; however, exenterative surgery in patients with locally advanced disease is associated with comparably inferior results and should not be advocated. If cystectomy is necessary, orthotopic urinary diversion can be performed safely in young motivated patients who wish to maintain a better quality of life with associated morbidity. Although the higher rate of incontinence and impotence after salvage procedures may detract from the quality of life, the impact of these long-term complications on the patient's overall well-being is less than previously believed, and most patients are satisfied with their treatment outcome and adjust well to the circumstances, accepting some increased degree of morbidity. This observation emphasizes the value of careful preoperative counseling and the discussion of treatment options and outcomes, which also should incorporate quality of life issues.

Endocrine therapy for recurrence after definitive radiotherapy in patients with prostate cancer

BACKGROUND

Long-term results were analyzed to evaluate the role of endocrine therapy in the management of local and distant recurrence of prostate cancer following external radiation therapy.

METHODS

Between 1976 and 1994, 92 patients with untreated prostate cancer underwent external beam radiation therapy alone. Endocrine therapy had been started when relapse was evident.

RESULTS

Failure was seen in 35 of 92 patients: 10 local, 19 distant and six biochemical failures. Endocrine treatment was performed in 28 patients with nine local and 19 distant failures. The cancer-specific survival rate from the endocrine treatment was 54.5% at 5 years. Prostate-specific antigen level in 20 of 20 patients (100%) decreased to below the normal limit 3 months after the start of endocrine therapy. In univariate analysis, T classification was the most significant variable for cancer-specific survival from the initial treatment.

CONCLUSIONS

A favorable outcome was achieved by endocrine therapy in patients who had relapsed after external beam radiation monotherapy. Even the recurrent tumor had a sensitivity to androgen. Patients with locally advanced disease (T2b and T3) had poorer prognosis than those with minimally extended disease (T1b and T2a).

Salvage cryotherapy for recurrent prostate cancer after radiation therapy: the Columbia experience

OBJECTIVES

Cryotherapy of the prostate represents a potential treatment for localized recurrent prostate cancer after radiation therapy. We report our experience and evaluate the predictive factors for prostate-specific antigen (PSA) recurrence.

METHODS

Between October 1994 and April 1999, 43 patients underwent salvage cryoablation. All patients had biopsy-proven recurrent prostate cancer without seminal vesicle invasion, negative bone scans, and negative lymph node dissection. Patients had received 3 months of combined hormonal therapy before cryosurgery. Biochemical recurrence-free survival (bRFS) was defined as a PSA value less than 0.1 ng/mL.

RESULTS

Complications included incontinence (9%), obstruction (5%), urethral stricture (5%), rectal pain (26%), urinary infection (9%), scrotal edema (12%), and hematuria (5%). The mean follow-up was 21.9 months (range 1.2 to 54). Twenty-six patients (60%) reached a serum PSA nadir less than 0.1 ng/mL, 16 (37%) had a PSA less than 4 ng/mL, and 1 (3%) had a PSA less than 10 ng/mL. The bRFS rate was 79% at 6 months and 66% at 12 months. The bRFS rate was higher for patients who had an undetectable postcryotherapy PSA than for patients who did not reach a PSA less than 0. 1 ng/mL (73% versus 30%, P = 0.0076). Using multivariate analysis, a PSA nadir greater than 0.1 ng/mL was an independent predictor of PSA recurrence.

CONCLUSIONS

Current salvage cryotherapy of the prostate can result in undetectable serum PSA levels with low morbidity. Our data support the current safety and efficacy profile. We believe that cryotherapy is a viable option in the treatment of patients who have biopsy-proven local failure after radiation therapy for prostate cancer. Further refinements in technique and equipment may enhance cryosurgical results.

Exposure to hyperbaric oxygen induces cell cycle perturbation in prostate cancer cells

Cell cycle synchronization of tumor cells by exposure to hyperbaric oxygenation (HBO) may increase the efficacy of chemotherapy or radiation by placing cells into a chemosensitive portion of the cycle. The purpose of the current study was to examine oxygen pressure-dependent relationships with respect to the cell cycle in prostate tumor cells in vitro. LNCaP cells were grown in an incubator at 21% O2 and then exposed to 100% oxygen at pressures up to 6 atmospheres (atm) for 1.5 h. Cells were then returned to the incubator and evaluated for DNA content by propidium iodide and new DNA synthesis with a pulse-chase experiment. Cell cycle effects were evaluated by flow cytometry. Exposure to HBO increased the percentage of cells synthesizing new DNA in a dose-dependent fashion: 0 atm, 44%; 6 atm, 65%. Cells that synthesize new DNA accumulate in G2/M as a function of partial pressure of oxygen. These results suggest that HBO induces cells to enter the cell cycle and accumulate in G2/M. Cell cycle synchronization and entry of senescent cells into the cell cycle suggest that HBO may be a useful adjuvant to chemotherapy or radiation in the treatment of prostate cancer. There are two potential mechanisms of action that may make HBO efficacious in the treatment of prostate cancer. HBO may potentiate cancer chemotherapeutic agents that cause damage to DNA during DNA synthesis or HBO may inhibit cell division causing accumulation in G2/M.

Predictors of survival for prostate carcinoma patients treated with salvage radical prostatectomy after radiation therapy

BACKGROUND

Salvage radical prostatectomy is a treatment option for patients with recurrent cancer following radiation therapy. This study was conducted to identify predictors of survival for patients treated with salvage radical prostatectomy.

METHODS

The authors studied 86 prostate carcinoma patients who underwent salvage radical prostatectomy for locally persistent or recurrent prostate carcinoma at Mayo Clinic between 1967 and 1996. The mean interval from radiation therapy to biopsy-proven recurrence was 3.7 years (range, 6 months to 17 years). Patient age at surgery ranged from 51 to 78 years (median, 66 years). The mean follow-up after surgery was 5.8 years (range, 1.0-15.2 years). Cox proportional hazards models were used to identify clinical and pathologic factors associated with distant metastasis free survival and cancer specific survival.

RESULTS

Actuarial distant metastasis free survival, cancer specific survival, and overall survival were 83%, 91%, and 85% at 5 years and 69%, 64%, and 54% at 10 years, respectively. In multivariate analysis, radical prostatectomy Gleason score and DNA ploidy were independent predictors of distant metastasis free survival and cancer specific survival.

CONCLUSIONS

Postirradiation Gleason score and DNA ploidy were highly predictive of the clinical outcomes of patients treated by salvage radical prostatectomy after radiation therapy.