Neoadjuvant hormonal downsizing of localized carcinoma of the prostate: effects on the volume of normal tissue irradiation

Impact of neoadjuvant androgen deprivation therapy on toxicity in intensity-modulated radiation therapy for prostate cancer

This study aimed to compare toxicities, prostate volume and dosimetry, between patients who underwent intensity-modulated radiation therapy (IMRT) combined with ≥3 months of neoadjuvant androgen deprivation therapy (NADT) and those without NADT for prostate cancer. In total, 449 patients with intermediate- and high-risk prostate cancer received 78 Gy IMRT in 39 fractions, of which 129 were treated without any ADT (non-ADT group) and 320 with NADT ≥3 months (NADT group). Adverse events and dose-volume indices were compared between the two groups retrospectively. The NADT group had a lower rate of acute grade 2 gastrointestinal (GI) toxicities (17% vs 25%, P = 0.063) and late grade 2 GI toxicities (P = 0.055), including a significantly lower rate of late grade 2 rectal hemorrhage (P = 0.033), compared with the non-ADT group. There were no cases of late grade 3 or higher GI toxicities. The average volume of the prostate in the NADT group was 38% smaller than that in the non-ADT group (43.7 vs 27.0 cm3, P < 0.001). Bladder V40Gy and V50Gy, and rectum V40Gy, V50Gy, V60Gy and V70Gy were significantly smaller in the NADT group. In the NADT group, no significant difference was observed in adverse events or dosimetry between the subgroups with NADT ≥12 and <12 months. Acute and late rectal toxicities were reduced by NADT within ≥3 months in accordance with reduced prostate volume and improved rectal dosimetry. This suggests a merit of administering neoadjuvant ADT ≥3 months for reducing rectal toxicities.

Testosterone as a Biomarker for Quality of Life (QOL) Following Androgen Deprivation Therapy (ADT) and Stereotactic Body Radiotherapy (SBRT)

BACKGROUND

Androgen deprivation therapy (ADT) causes fatigue and sexual dysfunction. The time to testosterone recovery depends on patient and treatment-specific characteristics. The kinetics of testosterone recovery in men treated with neoadjuvant ADT and stereotactic body radiotherapy (SBRT) is not well established. This study seeks to characterize testosterone recovery and evaluate its relationship with the improvement in patient-reported hormonal and sexual function.

METHODS

Institutional review board (IRB) approval was obtained for retrospective review of prospectively collected data. All patients with localized prostate cancer treated with short-course ADT (3-6 months of Leuprolide) and robotic SBRT (35-36.25 Gy in five fractions) at a single institution were included in this analysis. Testosterone levels were measured at the start of radiation, every 3 months for the first year, and every 6 months thereafter. Total testosterone recovery was defined as a serum level of >230 ng/dL. Sexual and hormonal function was recorded using the Expanded Prostate Index Composite (EPIC)-26 prior to ADT initiation, the first day of SBRT, and at each follow-up. The EPIC-26 subdomain scores were transformed to a 0-100 scale with higher scores reflecting less bother.

RESULTS

Between January 2009 and May 2018, 122 men with a median age of 72 years (range: 55-89 years) received ADT followed by SBRT. Thirty-two percent (N=39) were black and 27% [N=39 were obese (BMI > 30)]. The median pre-SBRT testosterone level was 15 ng/dL (range: 3-89 ng/dL). Around 77% (N=94) of patients received 3 months of ADT. The median pre-ADT EPIC-26 Hormone and Sexual Domain Scores were 94 and 41, respectively. At 12 months, 71% (N=87) of patients recovered to a eugonadal state with a mean recovery time of 4 months post-SBRT. Hormonal and sexual subdomain scores declined significantly following ADT but recovered to within the minimally important difference (MID) for sexual and hormonal domain scores by 12 months post-SBRT.

CONCLUSIONS

Testosterone recovery following short-course ADT with leuprolide and SBRT occurs rapidly in the majority of patients within one year after treatment. Quality of life domain improvements followed the testosterone recovery trend closely. Testosterone testing at follow-up appointments would allow for anticipatory counseling that may limit the bother associated with temporary quality of life decrements.

The effect of androgen deprivation therapy on 68Ga-PSMA tracer uptake in non-metastatic prostate cancer patients

PURPOSE

To evaluate the effect of neoadjuvant androgen deprivation treatment (ADT) on prostate-specific membrane antigen (PSMA) tracer uptake demonstrated in ⁶⁸Ga-PSMA-positron emission tomography (PET/CT) in non-metastatic hormone-naïve prostate cancer (PC) patients.

MATERIALS AND METHODS

The clinical data of 108 PC patients who received neoadjuvant ADT were retrospectively analyzed. All patients had a baseline ⁶⁸Ga-PSMA-PET/CT scan, and a second scan was delivered median of 2.9 months after the initiation of ADT. The maximum standardized uptake value (SUV_max) of primary tumor (SUV_p) and metastatic lymph nodes (SUV_ln) as well as PSA response were assessed between pre- and post-ADT ⁶⁸Ga-PSMA-PET/CT scans.

RESULTS

There were significant decreases in posttreatment serum PSA, SUV_p, and SUV_ln. A decrease in SUV_p was seen in 91 patients (84%) with a median value of 66% (range, 5-100%), while 17 patients (16%) had no change in or an increase in PSMA tracer uptake with a median value of 24% (range, 0-198%). Patients with Gleason score (GS) of 7 had significantly higher metabolic response rates compared to other patients. The disease progression was significantly higher only in patients with GS > 7 disease compared to GS 7 disease. The PSA response to ADT was the lowest in patients with ISUP high-grade tumors. A total of 16 patients (15%) had progressive disease, and in 9 patients (8%), radiotherapy decisions were modified according to posttreatment ⁶⁸Ga-PSMA-PET/CT scans.

CONCLUSIONS

The current study includes the largest number of patients analyzed to date and demonstrates that ADT causes a significant decrease in serum PSA values and SUV_p and SUV_ln. The authors demonstrate that ⁶⁸Ga-PSMA-PET/CT may be used as a quantitative imaging modality after neoadjuvant ADT in hormone-naïve non-metastatic PC patients.

Predictors of prostate volume reduction following neoadjuvant cytoreductive androgen suppression

Purpose

Limited duration cytoreductive neoadjuvant hormonal therapy (NHT) is used prior to definitive radiotherapeutic management of prostate cancer to decrease prostate volume. The purpose of this study is to examine the effect of NHT on prostate volume before permanent prostate brachytherapy (PPB), and determine associated predictive factors.

Material and methods

Between June 1998 and April 2012, a total of 1,110 patients underwent PPB and 207 patients underwent NHT. Of these, 189 (91.3%) underwent detailed planimetric transrectal ultrasound before and after NHT prior to PPB. Regression analysis was used to assess predictors of absolute and percentage change in prostate volume after NHT.

Results

The median duration of NHT was 4.9 months with inter quartile range (IQR), 4.2-6.6 months. Prostate-specific antigen (PSA) reduced by a median of 97% following NHT. The mean prostate volume before NHT was 62.5 ± 22.1 cm³ (IQR: 46-76 cm³), and after NHT, it was 37.0 ± 14.5 cm³ (IQR: 29-47 cm³). The mean prostate volume reduction was 23.4 cm³ (35.9%). Absolute prostate volume reduction was positively correlated with initial volume and inversely correlated with T-stage, Gleason score, and NCCN risk group. In multivariate regression analyses, initial prostate volume (p < 0.001) remained as a significant predictor of absolute and percent prostate volume reduction. Total androgen suppression was associated with greater percent prostate volume reduction than luteinizing hormone releasing hormone agonist (LHRHa) alone (p = 0.001).

Conclusions

Prostate volume decreased by approximately one third after 4.9 months of NHT, with total androgen suppression found to be more efficacious in maximizing cytoreduction than LHRHa alone. Initial prostate volume is the greatest predictor for prostate volume reduction.

The Effect of Androgen Deprivation Therapy Before Salvage Whole-gland Cryoablation After Primary Radiation Failure in Prostate Cancer Treatment

OBJECTIVE

To define the effects of androgen deprivation therapy (ADT) used prior to salvage cryoablation (SC) for the treatment of recurrent localized prostate cancer after radiation.

METHODS

Patients from the Cryo On-Line Database registry undergoing SC after radiation failure were divided according to whether they had previously received or not received ADT. Baseline characteristics including demographics and presalvage cancer risk were compared. Biochemical progression-free survival (bPFS) as defined by the Phoenix criteria was compared between the 2 groups as a whole and also in D'Amico risk-stratified subgroups. In addition, postsurgical complications such as urinary fistula, retention, incontinence, and erectile dysfunction were compared.

RESULTS

Two groups consisting of 254 and 486 patients with and without pre-SC ADT were analyzed. The patients who received ADT were younger (P = .003) and had higher presalvage D'Amico risks (P <.001). The 5-year bPFS was 63.8% and 39.3% for the hormone-naïve and the pre-SC ADT patients, respectively (P <.001). On subgroup analysis, the difference in 5-year bPFS was significant only for patients with a high D'Amico cancer risk (54.3% vs 30.5%; P = .013). On multivariate analysis, presalvage prostate-specific antigen (hazard ratio [HR], 1.7), Gleason score ≥ 8 (HR, 2.5), and use of pre-SC ADT (HR, 1.7) correlated with biochemical recurrence. Additionally, patients receiving pre-SC ADT experienced less urinary retention (P = .001) and incontinence (P = .008) but were more likely to be impotent (P = .010).

CONCLUSION

Patients receiving ADT before SC, especially those with high-risk prostate cancer, had worse 5-year bPFS. Added caution is needed when selecting patients having previously received ADT for salvage cryotherapy.

The clinical impact of pathological review on selection the treatment modality for localized prostate cancer in candidates for brachytherapy monotherapy

AIM

To evaluate the impact of pathological review by pathologist with genitourinary expertise (PGU) on treatment modality of localized prostate cancer, we analyzed Gleason grade (GG) migration and the final treatment decision in a cohort of patients designated for permanent prostate brachytherapy (PPB).

METHODS

From February 2005 to July 2010, a total of 247 patients with localized prostate cancer diagnosed by local community hospitals were referred to our hospital for PPB monotheray. All pathologic slides of prostate biopsies were reviewed by a single PGU. Patients ultimately selected their treatment modality from our recommendations based on the review. Indication for PPB monotherapy was the NCCN classification of patients as good or intermediate risk. In addition, patient with Primary GG 4 was regarded as unadapted case.

RESULTS

Six cases were reinterpreted as no cancer (2.4%). GG change occurred in 94 cases (38.1%) of which 77 (81.9%) were upgraded and 17 (18.1%) downgraded. Of the total 247 patients, 86 (34.8%) changed therapies and 30 (12.1%) did so based on the pathologic slide review.

CONCLUSIONS

Pathological review of biopsy specimens is mandatory for the determination of treatment modality especially in candidates for monotherapy of permanent prostate brachytherapy.

Androgen deprivation therapy for prostate cancer-review of indications in 2010

The discovery of androgen deprivation therapy (ADT) has been one of the most important advances in the treatment of prostate cancer. Here, the indications for the use of ADT are reviewed, together with the data supporting each indication. The settings for ADT use include cytoreduction; combined ADT and radiotherapy; pathologic node-positive disease; and recurrent, metastatic, or progressive prostate cancer.

Comparison of peripheral zone and central gland volume in patients undergoing intensity-modulated radiotherapy

BACKGROUND AND PURPOSE

The shrinking effect of androgen deprivation therapy (ADT) and radiotherapy (RT) on prostate gland volume is a known clinical finding. Until now, it is not known which part of the prostate shrinks more. We examined patients with and without ADT undergoing intensity-modulated RT (IMRT) and performed 3-dimensional measurements of the peripheral zone (PZ) and central gland (CG) with magnetic resonance imaging (MRI).

METHODS AND MATERIALS

Prostate gland volumes of PZ and CG between planning MRI and first available follow-up MRI were retrospectively determined in 44 patients with localized prostate carcinoma. A total of 24 patients had ADT with a median time interval of 5 months (range, 1.5-24 months). Median time interval between both MRI time points was 132 days (range, 104-224 days). Two observers performed PZ and CG delineation in consensus using planimetry. Volume changes over time were determined and compared.

RESULTS

Patients who had ADT showed smaller prostate volume in the first MRI (mean [SD], 32 [16.7] mL), which was still present after IMRT (28.1 [16.7] mL). Patients who had no ADT started with 44.6 (16.9) mL and showed 37.5 (13.9) mL after IMRT. Shrinking effect in PZ was significantly larger than in CG for all patients (-18.3% vs -6.3%, P < 0.05).

CONCLUSIONS

Because, typically, most tumors are located in PZ and this area also shows the largest shrinkage effect after IMRT, this should be taken into account for planning purposes. Notably, there are only minor differences in the relative shrinking effects between patients with and without ADT, although they start with different volumes.

The effect of concurrent androgen deprivation and 3D conformal radiotherapy on prostate volume and clinical organ doses during treatment for prostate cancer

In this study, we investigated the shrinking effect of concurrent three-dimensional conformal radiotherapy (3D-CRT) and androgen deprivation (AD) on prostate volume, and its possible impact on the dose received by the rectum and bladder during the course of 3D-CRT. The difference between the prostatic volumes determined on pre-treatment planning CT (PL-CT) and post-treatment CT (PT-CT) following a 3D-CRT course was assessed in 52 patients with localised prostate carcinoma. The changes in mean prostate volume when compared with PL-CT and PT-CT-based measurements were assessed. The pre- and post-treatment mean prostate volumes for the whole study population were 49.7 cm(3) and 41.0 cm(3) (p _ 0.02), respectively. The study cohort was divided into two groups depending on the duration of neoadjuvant androgen deprivation (NAD): 23 patients (44.7%) were designated as "short NAD" (< or =3 months; SNAD) and the remaining 29 (55.3%) as "long NAD" (>3 months; LNAD). Patients on SNAD experienced a significantly greater reduction in prostate volume compared with those on LNAD (14.1% vs 5.1%; p _ 0.03). A significant increase in rectum V(40-60) values in PT-CT compared with PL-CT was demonstrated. LNAD patients had significantly higher rectal V(50-70) values at PT-CT compared with the SNAD group. There was a significant decline in V(30)-V(75) bladder values in PT-CT compared with PL-CT in the SNAD group. In conclusion, a higher prostate volume reduction during 3D-CRT was demonstrated when RT planning was performed within 3 months of NAD. However, this reduction and daily organ motion may lead to an unpredictable increase in rectal doses.

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.

Changes of prostate gland volume with and without androgen deprivation after intensity modulated radiotherapy - A follow-up study

BACKGROUND AND PURPOSE

The shrinking effect of androgen deprivation therapy (ADT) on prostate volume is a known finding, but data on volume changes during radiotherapy are inconsistent. We examined patients with and without ADT undergoing intensity modulated radiotherapy (IMRT) and performed follow-up examinations to study volume changes before and after radiotherapy.

METHODS AND MATERIALS

Prostate volumes between planning magnetic resonance imaging (MRI) and last available follow-up MRI were retrospectively determined in 39 patients. Median time interval between first and last MRI was 233days (range 126-813). Two observers performed volume measurements in consensus and were blind to the timing of MRI. Volume changes over MRI were determined using the ellipsoid formula. Data of patients with and without ADT were compared by a linear mixed model.

RESULTS

Of 39 patients, 22 had ADT with a median duration of 5months (range 1-24). ADT patients showed lower prostate volume throughout the study period (-28% to 38%). Although individual shrinking effect was highly variable, patients treated with IMRT but without ADT showed a significantly larger volume reduction (26.1%) than patients with ADT (12.9%, p<0.05).

CONCLUSIONS

Patients undergoing IMRT show definite prostate shrinkage. The rate is slowed down after 6months in both groups, whereas the volume reduction is significantly larger in patients without ADT. Nevertheless there is no adding effect of ADT+IMRT vs. IMRT alone.

The nature and extent of urinary morbidity in relation to prostate brachytherapy urethral dosimetry

PURPOSE

This study investigates whether the location and dose of urethral radiation received during transperineal interstitial permanent prostate brachytherapy determine the degree and type of urinary symptoms experienced subsequently.

METHODS AND MATERIALS

Data from a prospectively acquired database of 219 men treated with transperineal interstitial permanent prostate brachytherapy using (125)I (prescribed dose 145Gy) between May 2001 and June 2003 were reviewed. To assess the effect of regional urethral dosimetry, the prostate was divided into equal thirds (proximal, mid, and apical) with doses beyond this considered distal. Mean and peak doses for each region were correlated with total International Prostate Symptom Score (IPSS) and the irritative and obstructive components of the score. IPSS values at 1 month postimplant, time to resolution of IPSS, and the need for catheterization were used as outcome variables and analyzed with respect to dose using logistic and linear regression.

RESULTS

Peak and average doses with standard deviations to the proximal urethra were 168 (24) and 147 (24)Gy, mid prostatic urethra 192 (24) and 181 (21)Gy, and apical urethra 201 (28) and 192 (26)Gy. Catheterization was required for 28 men and was predicted by larger pretreatment transrectal ultrasound (TRUS) volume (OR 1.06 per unit change; 95% CI 1.03-1.10; p<0.001) and lower UV(150) (OR 0.30; 95% CI 0.13-0.68; p=0.004) in multivariate analysis. Greater IPSS at baseline (p<0.001) and preoperative TRUS volume (p=0.012) but conversely smaller D(30) doses (p=0.003) were predictive of IPSS outcomes at 1 month. IPSS returned to within two points of baseline for 72.2% of men by 1 year and 83.3% by 24 months. This was predicted by higher IPSS at baseline (OR 6.0; 95% CI 2.72-13.22; p<0.001), higher D(30) (OR 1.17; 95% CI 1.01-1.36; p=0.031), and lower V(100) (OR 0.39; 95% CI 0.22-0.70; p=0.002). Prostatic urethral segmental dosimetry failed to predict the need for catheterization, the nature of the urinary symptoms, or their time to resolution.

CONCLUSIONS

Previously identified factors of importance for urinary morbidity such as pretreatment prostate volume and baseline urinary function were reemphasized in this study. Regional urethral dosimetry within contemporary practice does not seem to influence the nature or extent of urinary symptoms after prostate brachytherapy. Consequently, region sparing dosimetric modifications are not warranted to alter symptomatic outcomes.

Results of radiation therapy combined with neoadjuvant hormonal therapy for stage III prostate cancer: comparison of two different definitions of PSA failure

BACKGROUND

We herein report the clinical outcome of radical radiation therapy combined with neoadjuvant hormonal therapy (NHT) for stage III (International Union Against Cancer [UICC] 1997: UICC 97) prostate cancer. Prostate-specific antigen (PSA) failure-free survival was assessed according to two different definitions, and the appropriateness of each definition is discussed.

METHODS

Between October 1997 and December 2000, 27 patients with stage III prostate cancer were enrolled in this study. The median pretreatment PSA level was 29 ng/ml (range, 7.4-430 ng/ml). The Gleason score (GS) was 7 or more in 22 patients (81%). All patients received 3 months of NHT with a luteinizing hormone-releasing hormone (LH-RH) analogue, in combination with an antiandrogen (flutamide), given during the first 2 weeks, followed by 70-Gy external-beam radiation therapy (EBRT) in 35 fractions. The initial 46 Gy was given with a four-field technique, while the remainder was given with a dynamic conformal technique. No adjuvant hormonal therapy (AHT) was given.

RESULTS

The median follow-up time was 63 months. PSA levels decreased to the normal range (<4 ng/ml) after irradiation in all but one patient. The 5-year PSA failure-free survival was 34.8% according to the American Society for Therapeutic Radiology and Oncology (ASTRO) definition and it was 43.0% according to the "nadir plus 2" definition. Discordance of the results between the two definitions was seen in two patients. The 5-year overall and cause-specific survivals were 83.0% and 93.3%, respectively. No severe acute or late adverse effects were observed.

CONCLUSION

Seventy Gy of EBRT following 3 months of NHT produced therapeutic results comparable to those reported in other studies which used long-term AHT. The value of long-term AHT for Japanese men should be tested in a clinical trial.

The quality of life of men with locally advanced prostate cancer during neoadjuvant hormone therapy: data from the Medical Research Council RT01 trial (ISRCTN 47772397)

OBJECTIVE

To explore patients' quality of life (QoL) during neoadjuvant hormone therapy (HT) using data from the Medical Research Council RT01 trial of standard- (64 Gy/32-fraction) and high- (74 Gy/37-fraction) dose radiotherapy (RT, both given conformally).

PATIENTS AND METHODS

Of the 843 patients randomized to the RT01 trial, 316 completed the Functional Assessment Of Cancer Therapy core questionnaire with its additional prostate subscale, and the Short Form-36 Health Survey questionnaire with the University of California-Los Angeles Prostate Cancer Index before HT and again before starting RT. Three predefined QoL hypotheses were generated to focus the analyses.

RESULTS

For the three primary QoL analyses there was evidence that sexual functioning deteriorated, urinary function did not change, and there was a slight decline in physical well-being after > or = 3 months of HT. Sensitivity analyses confirmed these findings. Exploratory analyses also suggested that role functioning deteriorated, sleep was more disturbed, and there was an increase in fatigue. However, overall QoL was not reported to be affected and patients indicated an improvement in attitude and satisfaction with treatment.

CONCLUSIONS

In this group of men, many of whom reported reduced sexual functioning before treatment, the additional decline during HT seemed to be generally accepted as the price to pay for an appropriate cancer treatment. Nevertheless, these changes need to be discussed with patients before HT is commenced.

Duration of Testosterone Suppression after a 9.45mg Implant of the GnRH-Analogue Buserelin in Patients with Localised Carcinoma of the Prostate

OBJECTIVES

(1) To determine the duration of androgen deprivation after a single buserelin implant 9.45 mg in the neoadjuvant setting in combination with curative radiation therapy of carcinoma of the prostate, and (2) to evaluate the time to recovery of gonadal function, and the incidence and duration of hypogonadal symptoms.

METHODS

We prospectively evaluated 21 men with carcinoma of the prostate who received one implant of 9.45 mg buserelin subcutaneously. Release of buserelin, changes in serum testosterone concentration, hot flushing and sexual function over a 12-month study period were recorded.

RESULTS

Testosterone was suppressed below the castration limit (0.58 ng/ml=2 nmol/l) for 224 days (range, 139-309). The mean time to first return of testosterone above the castration limit was 246 days (range, 168-344); 50% of pre-treatment value was reached after 285 days (range, 218-370). The prevalence of hot flushing was 19 of 21 patients (90%) at 12 weeks. At the end of the study period, serum testosterone had reached 80% (range, 33%-166%) of pre-treatment concentration, sexual interest was present in 52%, erection was possible in 60%, and hot flushing remained in 24%.

CONCLUSION

A single injection of 3-month buserelin implant 9.45 mg suppresses serum testosterone below the castration limit for at least 6 months. Testosterone secretion recovers by 8-12 months. Hypogonadal symptoms decreased with the restoration of serum testosterone secretion. These data are clinically relevant regarding the dose schedule for buserelin and the patient information provided.

Outcome analysis of 300 prostate cancer patients treated with neoadjuvant androgen deprivation and hypofractionated radiotherapy

PURPOSE

Neoadjuvant androgen deprivation and radical radiotherapy is an established treatment for localized prostate carcinoma. This study sought to analyze the outcomes of patients treated with relatively low-dose hypofractionated radiotherapy.

METHODS AND MATERIALS

Three hundred patients with T1-T3 prostate cancer were treated between 1996 and 2001. Patients were prescribed 3 months of neoadjuvant androgen deprivation before receiving 5250 cGy in 20 fractions. Patients' case notes and the oncology database were used to retrospectively assess outcomes. Median follow-up was 58 months.

RESULTS

Patients presented with prostate cancer with poorer prognostic indicators than that reported in other series. At 5 years, the actuarial cause-specific survival rate was 83.2% and the prostate-specific antigen (PSA) relapse rate was 57.3%. Metastatic disease had developed in 23.4% of patients. PSA relapse continued to occur 5 years from treatment in all prognostic groups. Independent prognostic factors for relapse included treatment near the start of the study period, neoadjuvant oral anti-androgen monotherapy rather than neoadjuvant luteinizing hormone releasing hormone therapy, and diagnosis through transurethral resection of the prostate rather than transrectal ultrasound.

CONCLUSION

This is the largest reported series of patients treated with neoadjuvant androgen deprivation and hypofractionated radiotherapy in the United Kingdom. Neoadjuvant hormonal therapy did not appear to adequately compensate for the relatively low effective radiation dose used.

Late radiotherapy toxicity after prostate cancer treatment: Influence of hormonal therapy

OBJECTIVES

To analyze the impact of hormonal therapy (HT) on late gastrointestinal (GI) and genitourinary (GU) toxicity from external beam radiotherapy (RT).

METHODS

The records of 445 consecutive patients with prostate cancer undergoing RT with or without HT were reviewed. Late toxicity rates, using established toxicity scoring guidelines, were tabulated in the two groups and compared using the chi-square test. Ordered logit regression analyses were performed that included the major demographic, disease, and treatment factors.

RESULTS

The chi-square analyses demonstrated lower rates of GI toxicity (P = 0.013) and GU toxicity (P = 0.041) in the cohort receiving HT; this reduction in toxicity appeared to be consistent across different toxicity grades. However, on regression analysis, the only factor reaching statistical significance in predicting late GI and late GU toxicity was the radiation dose (P = 0.004 and P = 0.047, respectively). In particular, on regression analysis, HT did not reach statistical significance in predicting late GI toxicity (P = 0.229) or late GU toxicity (P = 0.910).

CONCLUSIONS

Observed late RT toxicity rates were generally similar in patients who did and did not receive HT. Thus, increased late RT toxicity should not be a major concern when deciding to add HT to RT for treatment of localized prostate cancer.

Patient-reported acute gastrointestinal toxicity in men receiving 3-dimensional conformal radiation therapy for prostate cancer with or without neoadjuvant androgen suppression therapy

OBJECTIVE

To investigate the impact of 2 months of neoadjuvant and 2 months of concurrent hormonal therapy on the acute gastrointestinal (GI) toxicities associated with 3-dimensional conformal radiation therapy (3D-CRT) for prostate adenocarcinoma.

METHODS

The study cohort consisted of 80 men who underwent 3D-CRT with (n=40) or without (n=40) neoadjuvant and concurrent hormonal therapy. Computerized tomography-based planning occurred after neoadjuvant hormonal therapy. All patients completed a previously validated, quality-of-life self-assessment tool on 7 GI symptoms, including diarrhea, urgency, pain, rectal bleeding, cramping, mucus, and tenesmus, at baseline and weekly during radiation therapy.

RESULTS

Patients who received hormonal therapy were more likely to have T2b, T2c, T3a, or T3b (P<0.001) or Gleason score 7, 8, or 9 (P=0.02) disease compared to those that did not. The dose delivered to the planning target volume was 70 Gy for both groups. Median radiation treatment volume was numerically smaller for the hormone group but not to a statistically significant degree (949 vs. 1043 cc, P=0.30). Patients who received hormonal therapy had less rectal pain (P<0.01) and tenesmus (P=0.02) but more rectal mucus (P=0.03) compared to those who did not.

CONCLUSIONS

Prostate gland volume reduction after androgen suppression therapy may reduce patient-reported acute GI toxicities associated with 3D-CRT for prostate cancer.

Impact of hormone therapy on acute radiotherapy toxicity in the treatment of prostate cancer

PURPOSE

To analyze the impact of neoadjuvant hormone therapy (HT) on acute gastrointestinal (GI) and genitourinary (GU) toxicity from radiotherapy (RT).

SCOPE

The toxicity rates of 480 consecutive prostate cancer patients were reviewed and compared using the chi2 test. Ordered logit regression analyses were performed including the major demographic, disease, and treatment factors. Although no reduction in acute GI toxicity from HT use was observed (P=0.067), a lower rate of acute GU toxicity was observed (P=0.002). No factor reached statistical significance on regression analysis.

CONCLUSIONS

Observed toxicity rates were similar or lower in patients receiving HT. Thus, increased RT toxicity should not be a concern when deciding to add neoadjuvant HT to RT for prostate cancer.

Long-term androgen deprivation increases Grade 2 and higher late morbidity in prostate cancer patients treated with three-dimensional conformal radiation therapy

PURPOSE

To determine whether the use of androgen deprivation (AD) increases late morbidity when combined with high-dose three-dimensional conformal radiation therapy (3D-CRT).

METHODS AND MATERIALS

Between May 1989 and November 1998, 1,204 patients were treated for prostate cancer with 3D-CRT to a median dose of 74 Gy. Patients were evaluated every 3-6 months. No AD was given to 945 patients, whereas 140 and 119 patients, respectively, received short-term AD (STAD; < or =6 months) and long-term AD (LTAD; > 6 months). Radiation morbidity was graded according to the Fox Chase modification of the Late Effects Normal Tissue Task Force late morbidity scale. Covariates in the multivariate analysis (MVA) included age, history of diabetes mellitus, prostate-specific antigen (PSA) level, Gleason score, T category, RT field size, total RT dose, use of rectal shielding, and AD status (no AD vs. STAD vs. LTAD).

RESULTS

The only independent predictor for Grade 2 or higher genitourinary (GU) morbidity in the MVA was the use of AD (p = 0.0065). The 5-year risk of Grade 2 or higher GU morbidity was 8% for no AD, 8% for STAD, and 14% for LTAD (p = 0.02). Independent predictors of Grade 2 or higher gastrointestinal (GI) morbidity in the MVA were the use of AD (p = 0.0079), higher total radiation dose (p < 0.0001), the lack of a rectal shield (p = 0.0003), and older age (p = 0.0009). The 5-year actuarial risk of Grade 2 or higher GI morbidity was 17% for no AD vs. 18% for STAD and 26% for LTAD (p = 0.017).

CONCLUSIONS

The use of LTAD seems to significantly increase the risk of both GU and GI morbidity for patients treated with 3D-CRT.

Technological advances in radiotherapy for the treatment of localised prostate cancer

There is good evidence that radiation dose escalation in localised prostate cancer is associated with increased cell kill. The traditional two-dimensional (2D) technique of treatment planning and delivery is limited by normal tissue toxicity, such that the dose that can be safely delivered to the prostate by external beam radiotherapy is 65-70 Gy. Several technological advances over the last 20 years have enhanced the precision of external beam radiotherapy (EBRT), and have resulted in improved outcomes. The three-dimensional conformal radiotherapy (3D-CRT) approach reduces the dose-limiting late side-effect of proctitis and has allowed for dose escalation to the whole prostate to 78 Gy. More recently, intensity modulated radiotherapy (IMRT), an advanced form of conformal therapy, has resulted in reduced rectal toxicity when using doses greater than 80 Gy. In addition, IMRT can potentially escalate the dose to specific parts of the prostate where there are resistant subpopulations of tumour clonogens, or can be used to extend the high-dose region to pelvic lymph nodes. The addition of androgen deprivation to conventional radiotherapy has an impact on survival and local control. Initial hormone therapy causes cytoreduction of the prostate cancer allowing for a reduction in radiotherapy volume as well as an additive effect on cell kill. Long-term adjuvant androgen deprivation has been shown to improve overall survival in more advanced tumours. Prostate brachytherapy is now a recognised treatment for those with low-risk disease. It achieves similar long-term outcome to other treatment modalities. Brachytherapy can be used as monotherapy for localised disease, or as boost treatment following conventional EBRT for locally advanced disease. New techniques are available to improve the precision of both target definition and treatment verification. This so-called image-guided radiotherapy will help to enhance the accuracy of dose delivery by correcting both for inter-fraction positional variation and for intra-fraction movement of the prostate in real-time and will allow for tighter tumour margins and avoidance of normal tissues, thereby enhancing the safety of treatment.

Phase III pilot study of dose escalation using conformal radiotherapy in prostate cancer: PSA control and side effects

Radical radiotherapy is a standard form of management of localised prostate cancer. Conformal treatment planning spares adjacent normal tissues reducing treatment-related side effects and may permit safe dose escalation. We have tested the effects on tumour control and side effects of escalating radiotherapy dose and investigated the appropriate target volume margin. After an initial 3-6 month period of androgen suppression, 126 men were randomised and treated with radiotherapy using a 2 by 2 factorial trial design. The initial radiotherapy tumour target volume included the prostate and base of seminal vesicles (SV) or complete SV depending on SV involvement risk. Treatments were randomised to deliver a dose of 64 Gy with either a 1.0 or 1.5 cm margin around the tumour volume (1.0 and 1.5 cm margin groups) and also to treat either with or without a 10 Gy boost to the prostate alone with no additional margin (64 and 74 Gy groups). Tumour control was monitored by prostate-specific antigen (PSA) testing and clinical examination with additional tests as appropriate. Acute and late side effects of treatment were measured using the Radiation Treatment and Oncology Groups (RTOG) and LENT SOM systems. The results showed that freedom from PSA failure was higher in the 74 Gy group compared to the 64 Gy group, but this did not reach conventional levels of statistical significance with 5-year actuarial control rates of 71% (95% CI 58-81%) in the 74 Gy group vs 59% (95% CI 45-70%) in the 64 Gy group. There were 23 failures in the 74 Gy group and 33 in the 64 Gy group (Hazard ratio 0.64, 95% CI 0.38-1.10, P=0.10). No difference in disease control was seen between the 1.0 and 1.5 cm margin groups (5-year actuarial control rates 67%, 95% CI 53-77% vs 63%, 95% CI 50-74%) with 28 events in each group (Hazard ratio 0.97, 95% CI 0.50-1.86, P=0.94). Acute side effects were generally mild and 18 weeks after treatment, only four and five of the 126 men had persistent > or =Grade 1 bowel or bladder side effects, respectively. Statistically significant increases in acute bladder side effects were seen after treatment in the men receiving 74 Gy (P=0.006), and increases in both acute bowel side effects during treatment (P=0.05) and acute bladder sequelae (P=0.002) were recorded for men in the 1.5 cm margin group. While statistically significant, these differences were of short duration and of doubtful clinical importance. Late bowel side effects (RTOG> or =2) were seen more commonly in the 74 Gy and 1.5 cm margin groups (P=0.02 and P=0.05, respectively) in the first 2 years after randomisation. Similar results were found using the LENT SOM assessments. No significant differences in late bladder side effects were seen between the randomised groups using the RTOG scoring system. Using the LENT SOM instrument, a higher proportion of men treated in the 74 Gy group had Grade > or =3 urinary frequency at 6 and 12 months. Compared to baseline scores, bladder symptoms improved after 6 months or more follow-up in all groups. Sexual function deteriorated after treatment with the number of men reporting some sexual dysfunction (Grade> or =1) increasing from 38% at baseline to 66% at 6 months and 1 year and 81% by year 5. However, no consistent differences were seen between the randomised groups. In conclusion, dose escalation from 64 to 74 Gy using conformal radiotherapy may improve long-term PSA control, but a treatment margin of 1.5 cm is unnecessary and is associated with increased acute bowel and bladder reactions and more late rectal side effects. Data from this randomised pilot study informed the Data Monitoring Committee of the Medical Research Council RT 01 Trial and the two studies will be combined in subsequent meta-analysis.

Acute morbidity related to treatment volume during 3D-conformal radiation therapy for prostate cancer

PURPOSE

To investigate the relation between acute toxicity and irradiated volume in the organs at risk during three-dimensional conformal radiation therapy for prostate cancer.

METHODS AND MATERIALS

From January to December 2001, we treated 132 prostate cancer patients to a prescribed target dose of 70 Gy. Twenty-six patients (20%) received irradiation to the prostate only (Group P), 86 patients (65%) had field arrangements encompassing the prostate and seminal vesicles (Group PSV) while 20 (15%) received modified pelvic fields (Group MPF). A four-field conformal box technique was used. Acute toxicity according to the RTOG scoring system was prospectively recorded throughout the course of treatment.

RESULTS

Overall, radiation was well tolerated with 11%, 16% and 35% Grade 2 gastro-intestinal (GI) toxicity and 19%, 34% and 35% Grade 2 or higher genito-urinary (GU) toxicity in Groups P, PSV and MPF, respectively. In univariate and multivariate analyses treatment group was a significant predictor for Grade 2 or higher acute morbidity. In multivariate logistic regression, the rectum dose-volume histogram parameters were correlated to the incidence of acute Grade 2 GI toxicity, with the fractional volumes receiving more than 37-40 Gy and above 70 Gy showing the statistically strongest correlation. The fractional bladder volume receiving more than 14-27 Gy showed the statistically strongest correlation with acute GU toxicity.

CONCLUSIONS

3D-CRT radiation therapy to 70 Gy for prostate cancer was well tolerated. Only two of the 132 patients in the cohort experienced acute bladder toxicity Grade 3, none had Grade 3 rectal toxicity. Uni- and multivariate analyses indicated that the volume treated was a significant factor for the incidence of Grade 2 or higher acute morbidity.

[Curative radiotherapy of localized prostate cancer. Treatment methods and results]

Radiation oncology has undergone rapid technical development during the last few years. The further development of treatment planning systems and treatment machines had a major impact on the improvement of radiation therapy results in prostate cancer. This paper presents different treatment modalities and results. Currently available are three-dimensional conformal radiation, intensity modulated radiation therapy (IMRT), high dose rate brachytherapy, and low dose rate brachytherapy (seed implantation). All modalities offer the possibility for dose escalation, which is essential for curative treatment. Dose escalation using these techniques makes it possible to reduce the dose for the surrounding organs at risk. Three-dimensional conformal radiation therapy can be delivered with doses up to 78 Gy. The biochemical control rate is up to 90% depending on the risk factors T stage, initial PSA, and Gleason score. The incidence of late side effects is <10%. IMRT is a newer modality for percutaneous radiotherapy. By individual dose modification in the treatment fields, doses >80 Gy can be delivered in small treatment volumes. Treatment has to be highly precise to avoid dose peaks in the organs at risk, i.e., rectum and bladder. The preliminary data for remission and toxicity rates are promising, but it is too early for final conclusions. For cases with high-risk factors such as PSA >10 ng/ml, Gleason score >6, and stage T3, percutaneous radiation can be combined with neoadjuvant or adjuvant hormonal treatment. Randomized trials showed an improvement of the results in favor of combined treatment. HDR brachytherapy in combination with external radiation is a good option for dose escalation in patients with locally advanced tumors and/or other high-risk factors. The biochemical control rates are between 60 and 84%, late effects occur in less than 10%. Seed implantation (LDR brachytherapy) as sole treatment is indicated for prognostically favorable situations (PSA <10 ng/ml, Gleason score < or =6, and T1c or T2a tumors). The biochemical control rates are between 80 and 90%. Toxicity consists of urine retention and proctitis, occurring in 10-20% of the patients.

Neoadjuvant androgen deprivation and prostate gland shrinkage during conformal radiotherapy

PURPOSE

The shrinking effect of 3-month neoadjuvant androgen deprivation (NAD) on preradiotherapy prostate gland volume is well documented. However, recently, it has been shown that the cancerous prostate gland keeps shrinking up to 12 months after NAD start. Thus, if such a reduction is not taken into account, a larger than planned portion of the surrounding normal tissues might shift in the high-dose region during conformal radiotherapy (3DCRT) course. The present study was undertaken to quantify this issue.

MATERIALS AND METHODS

Prostate gland volume reduction between planning CT (plCT) and the last week of 3DCRT (tmtCT) was prospectively assessed in 33 consecutive patients with localized prostate carcinoma. The median time interval between plCT and tmtCT was 2.5 months (2.1-2.7 months). A single observer was asked to draw on each slice prostate gland volume as appropriate. The observer was 'blind' to the timing of CT (plCT vs. tmtCT). In order to estimate intra-observer variability, prostate gland delineation was repeated twice for each data set. Mean prostate gland change, plCT and tmtCT cumulative dose volume histogram (DVH) calculations for the rectum were analyzed for each patient. Results were correlated to AD status and its duration before plCT. Means were compared by non-parametric rank tests.

RESULTS

Based on an internal protocol, 14 patients (42%) did not receive AD, while 19 patients (58%) had undergone neoadjuvant and concomitant AD. The median duration of AD before plCT ranged from 0.2 to 6 months (median: 2.9 months). Although individual data were highly variable, compared to plCT volume, mean prostate gland volume change at the end of 3DCRT was similar for patients receiving (-7.3%) or not (-7%) androgen deprivation (P=0.77). However, within the group of patients treated with hormones, patients starting AD within 3 months from plCT had a significantly larger reduction in prostate volume (-14.2%) than patients with longer NAD duration (-1.1%, P=0.03). At tmtCT, on average, patients undergoing 3DCRT within 3 months from AD start showed an increase of the amount of rectum receiving 40-75 Gy compared to plCT values. At 40 Gy (V40) the mean difference between tmtCT and plCT was +7.5%. In the other two groups, average variations of V40-70 were within +/-2% of plCT values. However, these differences are not significant.

CONCLUSION

For patients who undergo plCT and 3DCRT shortly after AD start, prostate gland shrinkage may be substantial. In some of these patients, this might lead to an unexpected increase of the percentage of rectal wall exposed to intermediate doses.

Primary radiation therapy for localized prostate cancer

Prostate cancer in men is similar to breast cancer in women; both cancers rank first, respectively, in incidence and are normally responsive to radiation therapy. In addition, advances in mammography help detect earlier breast cancers, and the development and refinement of prostatic specific antigen (PSA) has resulted in early detection of low-stage localized prostate cancers. This has generated debate over the proper management of localized prostate cancer. While there have not been any controlled, prospective, randomized trials of sufficient power to compare the various local therapies, based on the current available data, the three commonly used local modalities, surgery, and external beam radiation therapy and brachytherapy (radioactive seed implant), have similar efficacy controlling the disease up to 10 years in many patients. Technological advances in treatment delivery and planning have improved the treatment of prostate cancer with external-beam radiotherapy using three-dimensional conformal radiotherapy (3DCRT), ultrasound-guided transperineal implant, or intensity-modulated radiotherapy (IMRT), as well as proton or neutron beam based therapies.

Adjuvant androgen deprivation impacts late rectal toxicity after conformal radiotherapy of prostate carcinoma

To evaluate whether androgen deprivation impacts late rectal toxicity in patients with localised prostate carcinoma treated with three-dimensional conformal radiotherapy. One hundred and eighty-two consecutive patients treated with 3DCRT between 1995 and 1999 at our Institution and with at least 12 months follow-up were analysed. three-dimensional conformal radiotherapy consisted in 70-76 Gy delivered with a conformal 3-field arrangement to the prostate+/-seminal vesicles. As part of treatment, 117 patients (64%) received neo-adjuvant and concomitant androgen deprivation while 88 (48.4%) patients were continued on androgen deprivation at the end of three-dimensional conformal radiotherapy as well. Late rectal toxicity was graded according to the RTOG morbidity scoring scale. Median follow up is 25.8 (range: 12-70.2 months). The 2-year actuarial likelihood of grade 2-4 rectal toxicity was 21.8+/-3.2%. A multivariate analysis identified the use of adjuvant androgen deprivation (P=0.0196) along with the dose to the posterior wall of the rectum on the central axis (P=0.0055) and the grade of acute rectal toxicity (P=0.0172) as independent predictors of grade 2-4 late rectal toxicity. The 2-year estimates of grade 2-4 late rectal toxicity for patients receiving or not adjuvant hormonal treatment were 30.3+/-5.2% and 14.1+/-3.8%, respectively. Rectal tolerance is reduced in presence of adjuvant androgen deprivation.

Pre-treatment nomogram for biochemical control after neoadjuvant androgen deprivation and radical radiotherapy for clinically localised prostate cancer

Phase III studies have demonstrated the clinical benefit of adding neo-adjuvant androgen deprivation to radical radiotherapy for clinically localised prostate cancer. We have developed a nomogram to describe the probability of PSA control for patients treated in this way. Five hundred and seventeen men with clinically localised prostate cancer were treated with 3-6 months of neo-adjuvant androgen deprivation and radical radiotherapy (64Gy in 32#) between 1988 and 1998. Median presenting PSA was 20 ng x ml(-1), and 56% of patients had T3/4 disease. Multivariate analysis of pre-treatment factors was performed, and a nomogram developed to describe PSA-failure-free survival probability. At a median follow-up of 44 months, 233 men had developed PSA failure. Presenting PSA, histological grade and clinical T stage were all highly predictive of PSA failure on multivariate analysis. The nomogram score for an individual patient is given by the summation of PSA (<10=0, 10-19=16, 20-49=44, > or =50=100), grade (Gleason 2-4=0, 5-7=44, 8-10=81) and T stage (T1/2=0, T3/4=35). For a nomogram score of 0, 50, 100 and 150 points the 2 year PSA control rate was 93, 87, 75 and 54%, and the 5 year PSA control rate was 82, 67, 44 and 18%. These results are comparable to those using surgery or higher doses of radical radiotherapy alone. The nomogram illustrates the results of multivariate analysis in a visually-striking way, and facilitates comparisons with other treatment methods.

Normalization of serum testosterone levels in patients treated with neoadjuvant hormonal therapy and three-dimensional conformal radiotherapy for prostate cancer

PURPOSE

To determine the expected time to serum testosterone normalization after short-course neoadjuvant androgen deprivation therapy (NAAD) and three-dimensional conformal radiotherapy for patients with localized prostate cancer and to identify pretreatment predictors that correlated with the time to testosterone normalization.

METHODS

Between 1993 and 1999, 88 patients with localized prostate cancer, treated with NAAD and external beam radiotherapy, were prospectively monitored after treatment with sequential testosterone levels. NAAD was administered before and during the entire course of radiotherapy and discontinued at the end of treatment. The median duration of NAAD was 6 months. The actuarial rate of serum testosterone normalization from the end of treatment was evaluated, and the presence or absence of androgen deprivation-related symptoms was correlated with serum testosterone levels. Symptoms assessed included weight gain, loss of libido, breast tenderness, breast enlargement, hot flashes, and fatigue.

RESULTS

Serum testosterone levels returned to the normal range in 57 (65%) of the 88 patients and failed to normalize in 31 patients (35%). The median time to normalization was 18.3 months. The actuarial rate of normalization at 3, 6, 12, and 24 months was 10%, 26%, 38%, and 59%, respectively. In a multivariate analysis, a pretreatment testosterone level in the lower range of normal was the only variable that predicted for delayed testosterone normalization after NAAD (p = 0.00047). Among 45 patients with information concerning androgen deprivation-related symptoms recorded 1 year after cessation of NAAD, 24 (53%) had normalized testosterone levels, but in 21 patients (47%), the levels had not yet returned to normal. At 1 year, only 1 (4%) of 24 patients whose testosterone level had returned to normal experienced NAAD-related symptoms compared with 14 (67%) of 21 patients who did not have normal testosterone levels (p <0.001).

CONCLUSION

Testosterone levels often remain depressed for extended periods after cessation of short-course NAAD. Lower baseline testosterone levels predict for a delay in testosterone normalization, and the persistence of symptoms related to androgen deprivation correlates with low testosterone levels.

Acute and late radiotherapy toxicity in patients with inflammatory bowel disease

PURPOSE

To evaluate the incidence of gastrointestinal complications in patients with inflammatory bowel disease (IBD) receiving radiotherapy (RT) and to identify possibly avoidable factors associated with these complications.

METHODS AND MATERIALS

Twenty-four patients were identified and their records reviewed; all had a history of IBD before receiving RT to fields encompassing some portion of the gastrointestinal tract (Crohn's disease) or to the abdomen or pelvis (ulcerative colitis or IBD not otherwise specified).

RESULTS

Five of 24 patients (21%) experienced Grade > or =3 acute gastrointestinal toxicity; all 5 received concurrent chemotherapy. Two of 24 patients (8%) experienced Grade > or =3 late gastrointestinal toxicity. There were no significant correlations between complications and IBD type, prior IBD-related surgery, use of medications for IBD, or status of IBD.

CONCLUSION

Patients with IBD may have an increased risk for severe acute RT-related gastrointestinal complications that is more modest than generally perceived, because all patients who had Grade > or =3 acute complications in this study had received concurrent chemotherapy (p = 0.04). Further study is needed to assess this risk, as well as the impact of RT on these patients' future gastrointestinal morbidity.

Prostate volumes and organ movement defined by serial computerized tomographic scans during three-dimensional conformal radiotherapy

The aim of this study was to assess changes in prostate volumes and organ movement during a course of external beam irradiation using serial computerized tomographic (CT) scans and three-dimensional treatment planning software. Ten consenting prostate cancer patients underwent repeat CT scans at biweekly intervals during the course of external beam irradiation. The spacing of 5 mm was used because this spacing mimics our clinical treatment approach. Prostate locations were determined by merging CT images using bony anatomy and comparing the differences in the prostate volumes, the edges (anterior, posterior, superior, inferior, and lateral) and centers of the prostate (EoP and CoP, respectively). Compared to the 10 initial treatment planning CT scans, the prostate volume determined by the repeat CT scans tended to be smaller (approximately 14%, P < 0.001). The prostate volumes determined by repeat CT scans tended to be stable with a mean volume of 86% (S.D. = 18%) of the initial CT. When assessed by changes in the EoP, superior movements appeared to be the most common source for concern for adequate coverage of the prostate, while inferior movement was not seen. When assessed by changes in CoP, movement of > or = 3 mm was noted in 47% of the studies in the superior direction, with the average displacement being approximately 2.0 mm. In this study, the prostate volume tended to be smaller 2 weeks after the start of radiotherapy. Moreover, the prostate volumes defined by the serial CT scans were less reproducible than expected. Superior displacement of the prostate is the most common and significant type of displacement, while inferior movement is least frequent when patients are simulated with their rectums empty. Because of the magnitude of daily setup errors, organ movement, and problems with reproducibility in target definition, additional field edge reductions do not appear to be warranted during the delivery of three-dimensional conformal radiotherapy. Efforts should be directed at improving our ability to reduce organ movement and accurately targeting the prostate.

Effects of androgen deprivation on prostatic morphology and vascular permeability evaluated with mr imaging

PURPOSE

To assess magnetic resonance (MR) measures of vascular permeability of prostate cancer treated with androgen deprivation and to correlate these with morphologic appearances and serum prostate-specific antigen (PSA) levels.

MATERIALS AND METHODS

MR examinations in 56 consecutive patients with prostate cancer were performed before and after luteinizing hormone-releasing hormone analog treatment. T2-weighted and contrast medium-enhanced T1-weighted MR images were obtained. Pre- and posttreatment comparisons of morphologic features, glandular volume, and enhancement-related parameters (capillary permeability, leakage space, gadolinium accumulation) were made.

RESULTS

Fifty-five tumors were seen before treatment; 42, after treatment. Signal intensity in the peripheral zone and seminal vesicles decreased on T2-weighted images in 42 (75%) and 25 (45%) patients, respectively. Median volume in tumor decreased by 65% (95% CI: 55%, 76%); in central gland, by 30% (95% CI: 25%, 35%). Reductions in tumor permeability (P <.001) and changes in washout patterns were observed (P <.001). Tumor permeability reductions coincided with a decrease in serum PSA levels in 91% of patients. A weak correlation between tumor permeability and volume change was seen (r = 0.55, P =.04). Reductions in peripheral zone (P <.001) and central gland (P =.009) permeability were noted.

CONCLUSION

Androgen deprivation decreases tumor volume and vascular permeability and impairs detection of prostate cancers. Use of MR estimates of permeability may be an additional way of assessing prostatic tumor response to antiandrogen treatment.