Changes of Radiation Treatment Concept Based on 68Ga-PSMA-11-PET/CT in Early PSA-Recurrences After Radical Prostatectomy.

BACKGROUND AND PURPOSE: Salvage radiotherapy (SRT) is the main potentially curative treatment option for prostate cancer patients with post-prostatectomy PSA progression. Improved diagnostics by positron emission tomography/computed tomography (PET/CT) can lead to adjustments in treatment procedures (e.g. target volume of radiotherapy, androgen deprivation therapy). We analyzed the impact of 68Ga-PSMA-11-PET/CT on the target volume in early biochemical recurrence (PSA up to 0.5 ng/ml). PATIENTS AND METHODS: We retrospectively analyzed 76 patients with biochemical recurrence after radical prostatectomy in whom SRT was planned after 68Ga-PSMA-11-PET/CT. All patients had a PSA ≤0.5 ng/ml. An experienced radiation oncologist determined the radiotherapy concept, first with consideration of the PET/CT, second hypothetically based on the clinical and pathological features excluding PET/CT results. RESULTS: Without considering the PET/CT, all 76 patients would have been assigned to RT, 60 (79%) to the bed of the prostate and seminal vesicles alone, and 16 (21%) also to the pelvic lymph nodes because of histopathologic risk factors. Uptake indicative for tumor recurrence in 68Ga-PSMA-11-PET/CT was found in 54% of the patients. The median pre-PET/CT PSA level was 0.245 ng/ml (range 0.07-0.5 ng/ml). The results of the PET/CT led to a change in the radiotherapeutic target volume in 21 patients (28%). There were major changes in the target volume including the additional irradiation of lymph nodes or the additional or exclusive irradiation of bone metastases in 13 patients (17%). Minor changes including the additional irradiation of original seminal vesicle (base) position resulted in eight patients (11%). CONCLUSION: Using 68Ga-PSMA-11-PET/CT for radiation planning, a change in the treatment concept was indicated in 28% of patients. With PET/CT, the actual extent of the tumor can be precisely determined even with PSA values of ≤0.5 ng/ml. Thus, the treatment concept can be improved and individualized. This may have a positive impact on progression free survival. Our results warrant further prospective studies.

[Treatment of the primary tumour in oligometastatic prostate cancer]. / Behandlung des Primärtumors beim oligometastasierten Prostatakarzinom.

In the treatment of metastatic prostate cancer, significant improvements have recently been made. In addition to androgen deprivation, various options are available, such as anti-androgen receptor therapies with abiraterone and enzalutamide and taxane-based chemotherapy. It is still being discussed whether oligometastatic patients should only be treated systemically, or whether they benefit from additional local therapy for the primary tumour. Until mid-2018, there was no evidence-based recommendation to perform local prostate irradiation in newly diagnosed prostate cancer with distant metastases. At best, this could be indicated as an individual decision based on data from retrospective series. Accordingly, there were no recommendations in the guidelines. The data from the STAMPEDE study and the HORRAD study were published in 2018 /19 and clearly demonstrate the indication for local irradiation of the primary tumour in oligometastatic prostate cancer with less than 4 bone metastases. The following overview summarises the data from these two studies, evaluates them and finally gives a recommendation for the use of local prostate radiation therapy in the oligometastatic situation.

Interobserver variability, detection rate, and lesion patterns of 68Ga-PSMA-11-PET/CT in early-stage biochemical recurrence of prostate cancer after radical prostatectomy.

PURPOSE: 68Ga-PSMA-11-PET/CT is increasingly used in early-stage biochemical recurrence of prostate cancer to detect potential lesions for an individualized radiotherapy concept. However, subtle findings especially concerning small local recurrences can still be challenging to interpret and are prone to variability between different readers. Thus, we analyzed interobserver variability, detection rate, and lesion patterns systematically in a homogeneous patient population with low-level biochemical recurrence. METHODS: We analyzed 68Ga-PSMA-11-PET/CTs in 116 patients with status post-prostatectomy and PSA levels up to 0.6 ng/ml. None of them received ADT or radiotherapy beforehand. Images were interpreted and blinded by two nuclear medicine physicians (R1 and R2). Findings were rated using a 5-point scale concerning local recurrence, lymph nodes, bone lesions, and other findings (1: definitely benign, 2: probably benign, 3: equivocal, 4: probably malignant, 5: definitely malignant). In findings with substantial discrepancies of 2 or more categories and/or potentially leading to differences in further patient management, a consensus reading was done with a third reader (R3). Interobserver agreement was measured by Cohens Kappa analysis after sub-categorizing our classification system to benign (1 + 2), equivocal (3), and malignant (4 + 5). Time course of PSA levels after salvage treatment of patients rated as positive (4 + 5) was analyzed. RESULTS: The overall detection rate (categories 4 and 5) was 50% (R1/R2, 49%/51%) and in the PSA subgroups 0-0.2 ng/ml, 0.21-0.3 ng/ml, and 0.31-0.6 ng/ml 24%/27%, 57%/57%, and 65%/68%, respectively. Local recurrence was the most common lesion manifestation followed by lymphatic and bone metastases. The overall agreement in the Cohens Kappa analysis was 0.74 between R1 and R2. For local, lymphatic, and bone sites, the agreement was 0.76, 0.73, and 0.58, respectively. PSA levels of PSMA PET/CT-positive patients after salvage treatment decreased in 75% (27/36) and increased in 25% (9/36). A decrease of PSA, although more frequent in patients with imaging suggesting only local tumor recurrence (86%, 18/21), was also observed in 67% (10/15) of patients with findings of metastatic disease. CONCLUSIONS: In a highly homogeneous group of prostate cancer patients with early-stage biochemical recurrence after radical prostatectomy, we could show that 68Ga-PSMA-11-PET/CT has a good detection rate of 50% which is in accordance with literature, with clinically relevant findings even in patients with PSA < 0.21 ng/ml. The interobserver variability is low, particularly concerning assessment of local recurrences and lymph nodes. Therefore, PSMA-PET/CT is a robust diagnostic modality in this patient group for therapy planning.

Effect of early salvage radiotherapy at PSA < 0.5 ng/ml and impact of post-SRT PSA nadir in post-prostatectomy recurrent prostate cancer.

BACKGROUND: For patients with recurrent prostate cancer after radical prostatectomy (RP), salvage radiotherapy (SRT) offers a second chance of cure. European guidelines (EAU) recommend SRT at a PSA < 0.5 ng/ml. We analyze the efficacy of SRT given according to this recommendation and investigate the predictive power of the post-SRT PSA nadir. METHODS: Between 1998 and 2013, 301 patients of two university hospitals received SRT at a PSA < 0.5 ng/ml (median 0.192 ng/ml, IQR 0.110-0.300). Patients, who previously received androgen deprivation therapy, were excluded. All patients had 3D-conformal RT or intensity-modulated radiotherapy (IMRT, n = 59) (median 66.6 Gy). The median follow-up was 5.9 years. Progression and overall survival were the endpoints. RESULTS: After SRT, 252 patients re-achieved an undetectable PSA. In univariate analysis, pre-RP PSA ≥ 10 ng/ml, pT3-4, Gleason score (GS) 7-10 or 8-10, negative surgical margins, post-RP PSA ≥ 0.1 ng/ml, pre-SRT PSA ≥ 0.2 ng/ml and post-SRT PSA nadir ≥ 0.1 ng/ml correlated unfavorably with post-SRT progression. In a multivariable Cox model, pT3-4, GS 7-10, negative margins and a pre-SRT PSA ≥ 0.2 ng/ml were significant risk factors. If the post-SRT PSA was added to the analysis, it dominated the outcome (HR = 9.00). Of the patients with a pre-SRT PSA < 0.2 ng/ml, only 9% failed re-achieving an undetectable PSA. Overall survival in these patients was 98% after 5.9 years compared to 91% in patients with higher pre-SRT PSA (Logrank p = 0.004). CONCLUSIONS: SRT at a PSA < 0.2 ng/ml correlates significantly with achieving a post-SRT undetectable PSA (<0.1 ng/ml) and subsequently with improved freedom from progression. Given these overall favorable outcomes, whether additional androgen deprivation therapy is required for these men requires further study.

Prostate-specific antigen after salvage radiotherapy for postprostatectomy biochemical recurrence predicts long-term outcome including overall survival.

BACKGROUND: For patients with recurrent prostate cancer after radical prostatectomy (RP), salvage radiotherapy (SRT) is a second chance of cure. However, depending on risk factors, 40-70% of the patients experience further progression. With a focus on the pre- and post-SRT serum level of the prostate-specific antigen (PSA), we assessed the determinants of the long-term outcome after SRT. PATIENT AND METHODS: Between 1997 and 2011, 464 patients received 3D-conformal SRT with median 66.6 Gy. The median PSA level before SRT was 0.31 ng/ml. In our retrospective analysis, post-SRT progression was defined as either a rising PSA >0.2 ng/ml above the nadir, or the application of anti-androgens or clinical recurrence. A PSA <0.1 ng/ml was termed undetectable. We analyzed the data with the Kaplan-Meier method (Logrank test) and multivariable Cox regression. RESULTS: The median follow-up was 5.9 years. Overall, 178 patients had recurrence, 13 developed distant metastases and 30 died. Univariate, a pre-RP PSA <10 ng/ml, pathological stage pT <3, Gleason score <8, positive surgical margins, a pre-SRT PSA <0.2 ng/ml and a post-SRT PSA nadir <0.1 ng/ml correlated with fewer and later second recurrences. In a multivariable Cox model, pT, Gleason score, margin status and pre-SRT PSA were significant covariates of progression. If the post-SRT PSA response was included in the regression analysis, then a nadir ≥0.1 ng/ml was the strongest risk factor. Initiating SRT at a PSA <0.2 ng/ml correlated with a post-SRT PSA <0.1 ng/ml. Men who achieved an undetectable post-SRT PSA nadir also had lower rates of metastases and a better overall survival. However, there were too few events for Cox regression analysis of these two endpoints. CONCLUSIONS: Early SRT at a PSA <0.2 ng/ml correlates with re-achieving an undetectable PSA, which predicts improved freedom from progression and metastases and better overall survival.

Comparison of seroma production in breast conserving surgery with or without intraoperative radiotherapy as tumour bed boost.

INTRODUCTION: One of the most common complications in breast conserving surgery is seroma formation. The origin of seroma formation remains unclear. While intraoperative radiotherapy (IORT) has been shown to be an alternative to whole breast irradiation, the influence on seroma production is unclear. Therefore, this analysis compares seroma production in patients with breast conserving surgery with or without IORT as tumour bed boost during breast conserving surgery. METHOD: A retrospective analysis of seroma production in patients with nodal-negative (pN0sn) pT1/2 primary breast cancer treated between September 2010 and October 2013 at the Breast Cancer Centre, University Hospital Ulm was performed. Patients with neoadjuvant chemotherapy, previous breast/axillary surgery or more than one intervention were excluded. IORT was applied as a tumour bed boost with 50-kV X-rays (Intra beam(®)) delivering 9 Gy at the applicator surface. Seroma formation was measured using wound drains placed in breast and in axilla. RESULTS: Data of 152 patients (99 -IORT; 53 +IORT) were available for analysis. No significant differences between patients with or without IORT with regard to seroma production and number of days until drain removal were found (all p > 0.05). CONCLUSION: Patients with IORT encountered no increased seroma production and removal of the drains was not delayed compared to patients with breast conserving surgery only. Our results indicate that IORT does not increase the seroma production compared to surgery alone.

The PSA-response to salvage radiotherapy after radical prostatectomy correlates with freedom from progression and overall survival.

BACKGROUND AND PURPOSE: In a retrospective analysis, we examined factors influencing the outcome of prostate cancer (PCa) patients receiving salvage radiotherapy (SRT) for PSA recurrence after radical prostatectomy (RP). MATERIAL AND METHODS: 306 patients received 3D-conformal SRT at a median pre-SRT PSA of 0.298 ng/ml. Post-SRT progression was defined as PSA ⩾0.2 ng/ml above nadir and rising further, or hormone treatment, or clinical recurrence. Data were analyzed with the Kaplan-Meier method and multivariable Cox regression. RESULTS: Application of SRT at a PSA <0.2 ng/ml correlated significantly with achieving a post-SRT PSA nadir <0.1 ng/ml and with improved freedom from progression (median follow-up 7.2 years). The post-SRT nadir <0.1 ng/ml correlated significantly with less recurrences and with better overall survival. In multivariable Cox analysis restricted to pre-SRT parameters, a pre-SRT PSA ⩾0.2 ng/ml had the strongest impact (hazard ratio 2.4) on progression. If the post-SRT PSA nadir was included in the model, then failing the nadir was the most important risk factor (hazard ratio 8.1). CONCLUSIONS: Early SRT at a PSA <0.2 ng/ml is a favorable treatment option for post-RP biochemical recurrence. It correlated with a post-SRT PSA-nadir <0.1 ng/ml which was associated with improved freedom from progression and overall survival.

Evaluation of Sentinel Lymph Node Dose Distribution in 3D Conformal Radiotherapy Techniques in 67 pN0 Breast Cancer Patients.

Introduction. The anatomic position of the sentinel lymph node is variable. The purpose of the following study was to assess the dose distribution delivered to the surgically marked sentinel lymph node site by 3D conformal radio therapy technique. Material and Method. We retrospectively analysed 70 radiotherapy (RT) treatment plans of consecutive primary breast cancer patients with a successful, disease-free, sentinel lymph node resection. Results. In our case series the SN clip volume received a mean dose of 40.7 Gy (min 28.8 Gy/max 47.6 Gy). Conclusion. By using surgical clip markers in combination with 3D CT images our data supports the pathway of tumouricidal doses in the SN bed. The target volume should be defined by surgical clip markers and 3D CT images to give accurate dose estimations.

Prostate-specific antigen persistence after radical prostatectomy as a predictive factor of clinical relapse-free survival and overall survival: 10-year data of the ARO 96-02 trial.

OBJECTIVE: The ARO 96-02 trial primarily compared wait-and-see (WS, arm A) with adjuvant radiation therapy (ART, arm B) in prostate cancer patients who achieved an undetectable prostate-specific antigen (PSA) after radical prostatectomy (RP). Here, we report the outcome with up to 12 years of follow-up of patients who retained a post-RP detectable PSA and received salvage radiation therapy (SRT, arm C). METHODS AND MATERIALS: For the study, 388 patients with pT3-4pN0 prostate cancer with positive or negative surgical margins were recruited. After RP, 307 men achieved an undetectable PSA (arms A + B). In 78 patients the PSA remained above thresholds (median 0.6, range 0.05-5.6 ng/mL). Of the latter, 74 consented to receive 66 Gy to the prostate bed, and SRT was applied at a median of 86 days after RP. Clinical relapse-free survival, metastasis-free survival, and overall survival were determined by the Kaplan-Meier method. RESULTS: Patients with persisting PSA after RP had higher preoperative PSA values, higher tumor stages, higher Gleason scores, and more positive surgical margins than did patients in arms A + B. For the 74 patients, the 10-year clinical relapse-free survival rate was 63%. Forty-three men had hormone therapy; 12 experienced distant metastases; 23 patients died. Compared with men who did achieve an undetectable PSA, the arm-C patients fared significantly worse, with a 10-year metastasis-free survival of 67% versus 83% and overall survival of 68% versus 84%, respectively. In Cox regression analysis, Gleason score ≥8 (hazard ratio [HR] 2.8), pT ≥ 3c (HR 2.4), and extraprostatic extension ≥2 mm (HR 3.6) were unfavorable risk factors of progression. CONCLUSIONS: A persisting PSA after prostatectomy seems to be an important prognosticator of clinical progression for pT3 tumors. It correlates with a higher rate of distant metastases and with worse overall survival. A larger prospective study is required to determine which patient subgroups will benefit most from which treatment option.

Adjuvant radiotherapy versus wait-and-see after radical prostatectomy: 10-year follow-up of the ARO 96-02/AUO AP 09/95 trial.

BACKGROUND: Local failure after radical prostatectomy (RP) is common in patients with cancer extending beyond the capsule. Three prospectively randomized trials demonstrated an advantage for adjuvant radiotherapy (ART) compared with a wait-and-see (WS) policy. OBJECTIVE: To determine the efficiency of ART after a 10-yr follow-up in the ARO 96-02 study. DESIGN, SETTING, AND PARTICIPANTS: After RP, 388 patients with pT3 pN0 prostate cancer (PCa) were randomized to WS or three-dimensional conformal ART with 60 Gy. The present analysis focuses on intent-to-treat patients who achieved an undetectable prostate-specific antigen after RP (ITT2 population)--that is, 159 WS plus 148 ART men. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary end point of the study was progression-free survival (PFS) (events: biochemical recurrence, clinical recurrence, or death). Outcomes were compared by log-rank test. Cox regression analysis served to identify variables influencing the course of disease. RESULTS AND LIMITATIONS: The median follow-up was 111 mo for ART and 113 mo for WS. At 10 yr, PFS was 56% for ART and 35% for WS (p<0.0001). In pT3b and R1 patients, the rates for WS even dropped to 28% and 27%, respectively. Of all 307 ITT2 patients, 15 died from PCa, and 28 died for other or unknown reasons. Neither metastasis-free survival nor overall survival was significantly improved by ART. However, the study was underpowered for these end points. The worst late sequelae in the ART cohort were one grade 3 and three grade 2 cases of bladder toxicity and two grade 2 cases of rectum toxicity. No grade 4 events occurred. CONCLUSIONS: Compared with WS, ART reduced the risk of (biochemical) progression with a hazard ratio of 0.51 in pT3 PCa. With only one grade 3 case of late toxicity, ART was safe. PATIENT SUMMARY: Precautionary radiotherapy counteracts relapse after surgery for prostate cancer with specific risk factors.

Salvage radiotherapy in patients with prostate cancer and biochemical relapse after radical prostatectomy : Long-term follow-up of a single-center survey.

BACKGROUND AND PURPOSE: In patients with prostate cancer (PC) and biochemical relapse after radical prostatectomy, salvage radiotherapy (SRT) could improve PC-specific survival (PCSS) but the timing for initiation is still under discussion. We have demonstrated a low rate of biochemical relapses in a patient series with very low pre-SRT PSA levels after a median follow-up of 42 months. Here, we present an update of that study. PATIENTS AND METHODS: Overall, 151 patients were analyzed. A biochemical relapse after SRT was diagnosed when the PSA exceeded the post-SRT nadir by 0.2 ng/ml with subsequent increase. Parameters with significant impact on biochemical progression-free survival (BPFS), PCSS, and overall survival (OS) in univariate analysis were included in a multiple Cox regression analysis. RESULTS: After a median follow-up of 82 months, 18 patients (12%) had died with 10 (6.6%) deaths being PC-related. A biochemical progression was diagnosed in 83 patients (55%). Univariate analysis revealed a significant impact of pre-SRT PSA level, Gleason score, and PSA doubling time (PSADT) on BPFS and for initial tumor stage and Gleason score on OS. Multivariate analysis confirmed the impact of pre-SRT PSA level, Gleason score, and PSADT on BPFS and tumor stage on OS. CONCLUSION: In this update, the rate of biochemical relapses increased compared with our previous data. Compared to similar studies, we found a remarkably low rate of PC-related deaths. Our data support early initiation of SRT. However, this treatment strategy, triggered by very low PSA levels, could carry the risk of overtreatment in at least a subset of patients.

Radiotherapy in the management of prostate cancer after radical prostatectomy.

The choice of treatment options for prostate cancer patients who have undergone radical prostatectomy depends on their risk profile, which is determined by the tumor node metastasis (TNM) status, histopathologic findings, and the pre- and post-radical prostatectomy PSA characteristics. The results of large clinical studies with a 10-year follow-up or more are the backbone of predictive models for risk estimates that incorporate these criteria and also for guideline recommendations. For low-to-intermediate-risk prostate cancer patients and older patients, observation with--in case of biochemical recurrence--early salvage radiotherapy can be advised after R0 resection, thus, avoiding overtreatment. After R1 resection, adjuvant radiotherapy should be considered. Patients with two or more positive lymph nodes and/or with distant metastasis may benefit from adjuvant hormone deprivation therapy. Beyond this rough outline, detailed analysis of subgroups is still required (and ongoing) to enable individually optimized treatment.

Adjuvant radiotherapy or early salvage radiotherapy in pT3R0 or pT3R1 prostate cancer.

PURPOSE OF REVIEW: As the appropriate management of patients after prostatectomy is still controversial, the two major approaches, adjuvant radiotherapy (ART) vs. prostate-specific antigen-based surveillance and - upon biochemical recurrence - salvage radiotherapy (SRT) are discussed. RECENT FINDINGS: Three prospectively randomized clinical trials into ART with 5-12 years median follow-up and overall 1800 patients show a significant gain in freedom from biochemical recurrence after prostatectomy and adjuvant irradiation (hazard ratio ∼0.5). Only one study reported an improved overall survival (hazard ratio 0.72). Patients with pT3 and positive surgical margins are the most likely to profit from ART. Retrospective analyses of adjuvant vs. SRT suggest a similar oncological outcome if SRT is given early after recurrence, that is at a prostate-specific antigen of 0.5 ng/ml or less. Also, toxicity is similar with the two strategies. With positive lymph nodes, hormone therapy and optionally extended field radiotherapy can be recommended. SUMMARY: The alternative ART or surveillance along with SRT after prostatectomy cannot yet be decided on conclusively. Compliance, physical side-effects, psychological aspects and life expectancy should be taken into account when discussing treatment options. Ongoing and planned trials will hopefully identify subgroups that profit most from one or the other strategy.

Phase 3 study of adjuvant radiotherapy versus wait and see in pT3 prostate cancer: impact of pathology review on analysis.

BACKGROUND: In a randomised trial, radical prostatectomy (RP) followed by adjuvant radiotherapy (aRT) was compared with RP alone in patients with pT3 pN0 prostate cancer with or without positive margin at local pathology (German Cancer Society trial numbers ARO 96-02/AUO AP 09/95). OBJECTIVE: A pathology review was performed on 85% of RP specimens of patients to investigate the influence of pathology review on the analysis. DESIGN, SETTING, AND PARTICIPANTS: Patients post-RP (n=385) were randomised before achieving an undetectable prostate-specific antigen (PSA) level to either wait and see (n=192) or 60Gy aRT (n=193). Of 307 patients with undetectable PSA after RP, 262 had pathology review. These results were included prospectively into the analysis. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Agreement between local and review pathology was measured by the total percentage of agreement and by simple kappa statistics. The prognostic reliability for the different parameters was analysed by Cox regression model. Event-free rates were determined by Kaplan-Meier analysis with a median follow-up of 40 mo for the wait-and-see arm and 38.5 mo for the aRT arm. RESULTS AND LIMITATIONS: There was fair concordance between pathology review and local pathologists for seminal vesicle invasion (pT3c: 91%; κ=0.76), surgical margin status (84%; κ=0.65), and for extraprostatic extension (pT3a/b: 75%; κ=0.74). Agreement was much less for Gleason score (47%; κ=0.42), whereby the review pathology resulted in a shift to Gleason score 7. In contrast to the analysis of progression-free survival with local pathology, the multivariate analysis including review pathology revealed PSMs and Gleason score >6 as significant prognostic factors. CONCLUSIONS: Phase 3 studies of postoperative treatment of prostate cancer should be accomplished in the future with a pathology review. In daily practice, a second opinion by a pathologist experienced in urogenital pathology would be desirable, in particular, for high-risk patients after RP.

Salvage radiotherapy in patients with persistently detectable PSA or PSA rising from an undetectable range after radical prostatectomy gives comparable results.

PURPOSE: Salvage radiotherapy (SRT) is applied routinely in patients with a biochemical relapse after radical prostatectomy (RP). Although the detection threshold for relapse after RP has steadily been lowered, only about 30% of the SRT patients achieve a durable response. We have previously shown the association between a PSA decrease below detectable levels after SRT and biochemical progression-free survival (BPFS). After recalculating our data according to a more recent definition of biochemical failure after SRT, we now show the significance of the post-RP PSA nadir. MATERIALS AND METHODS: Among 159 prostate cancer patients without hormonal treatment after RP, SRT was given to 72 patients with persistently detectable PSA after RP and to 87 whose PSA increased out of an undetectable range. The median pre-SRT PSA was 0.29 ng/ml for the former group and 0.34 ng/ml for the latter group. A radiation dose of 66.6 Gy was applied to the prostate bed. RESULTS: The overall median follow-up time was 41.7 months. The probability for BPFS after this period was 52.8% in 72 patients with persistently detectable PSA after RP and 65.4% in 87 patients who had a post-RP PSA nadir below detection limit. Univariate and multivariate analyses showed no significant difference in BPFS of both patient groups (p > 0.05). CONCLUSION: Our findings suggest that SRT is a viable treatment option for patients with persistently detectable PSA, giving similar results as in patients whose PSA increases out of an undetectable range after RP.

Second cancer after radiotherapy, 1981-2007.

BACKGROUND AND PURPOSE: Today, there is growing concern about radiotherapy induced secondary malignancies. We analysed the incidence and dose dependence of second cancer. MATERIAL AND METHODS: The study includes 12,000 one-year survivors of radiotherapy, treated between 1981 and 2007. For risk estimates a public databank on cancer in Germany served as reference. Contralateral second breast cancer, second oesophageal and colorectal cancer were analysed with retrospective dosimetry. GI-tract data were used for risk modelling. RESULTS: The incidence rate of second cancers (493 cases) was ~1% per year. Contralateral breast cancer was the most frequent entity (relative risk RR=2.8). The scatter-dose gradient (2-3 Gy) across the contralateral breast did not cause a detectable risk gradient. There was an increased risk for second head and neck cancer (RR=5.1) and for male oesophageal cancer (RR=5.8). For both entities, dose response modelling with case-control data predicted maximum curves with peak induction at 1-5 Gy and positive excess absolute risk values at high doses. CONCLUSIONS: A survey of second cancer after radiotherapy requires follow-up over decades. Preliminary dose response modelling albeit with low case numbers suggests an increased risk from multiportal techniques. To improve risk assessment, prospective out-of-field dosimetry and long-term multicentre data collection are recommended.

Salvage radiotherapy after prostatectomy - what is the best time to treat?

PURPOSE: Salvage radiotherapy (SRT) is applied routinely in patients with biochemical relapse after radical prostatectomy (RP). However, only ∼30% of these patients achieve a durable response after 10 years. As a standard, 66 Gy are given, ideally with a PSA below 0.5 ng/ml. We tried to determine more precisely the optimal PSA for starting SRT. MATERIAL AND METHODS: In 301 prostate cancer patients without hormonal treatment, we analysed the impact on the biochemical response (bNED) to SRT of two pre-SRT PSA levels, namely below or above the median of 0.28 ng/ml. RESULTS: The median follow-up time for the entire group was 30 months. In 151 patients, SRT commenced at a PSA ≤ 0.28 ng/ml, in 150 at > 0.28 ng/ml. Eighty-two patients (27%) developed biochemical progression during follow up. The calculated two-year bNED was 74% for the entire group, 78% versus 61% for a PSA ≤ or > 0.28 ng/ml, respectively. In multivariate analysis, pT(3b), resection status, pre-SRT PSA dichotomized at median, PSA post-SRT undetectable, and PSA doubling time were statistically significant independent predictors of progression after SRT. CONCLUSIONS: Our findings suggest that a PSA of ≤ 0.28 ng/ml improves bNED compared with a PSA before SRT of > 0.28 ng/ml.

Dose escalation for patients with decreasing PSA during radiotherapy for elevated PSA after radical prostatectomy improves biochemical progression-free survival: results of a retrospective study.

PURPOSE: The optimal dose for salvage radiotherapy (SRT) after radical prostatectomy (RP) is still not defined. It should be at least 66 Gy. In the present study, the suitability of PSA regression as a selection criterion for an SRT dose escalation to 70.2 Gy was examined. PATIENTS AND METHODS: Between 1997 and 2007, 301 prostate cancer patients received SRT after RP at the Charité - University Medicine Berlin, Campus Benjamin Franklin. None of the patients had antihormone therapy prior to SRT. A total of 234 patients received 66.6 Gy. From 2002 on, 67 patients with a PSA decrease during SRT were irradiated with 70.2 Gy. The influence of this selection and dose escalation on freedom from biochemical progression (bNED) was analyzed. RESULTS: The median follow-up of the whole group was 30 months, the median pre-SRT PSA was 0.28 ng/ml. Of the patients, 27% (82/301) developed biochemical progression, 31% from the 66.6 Gy cohort (73/292) and 13% from the 70.2 Gy cohort (9/67) (p = 0.01). The calculated 2-years bNED was 74% for the whole group, 88% vs. 71% after 70.2 Gy and 66.6 Gy, respectively (p = 0.01). In a multivariate analysis, the total dose (p = 0.017), the re-achievement of an undetectable PSA after SRT (p = 0.005), and the infiltration of the seminal vesicles (p = 0.049) were independent parameters of bNED. CONCLUSION: Our analysis suggests that patient selection during SRT for a dose escalation to 70.2 Gy can improve the freedom from biochemical progression in patients with SRT after RP.

Second malignancies in high­dose areas of previous tumor radiotherapy.

PURPOSE: To characterize second tumors that developed in or near the high-dose areas of a previous radiotherapy, regarding their frequency, entities, latency, and dose dependence. PATIENTS AND METHODS: 9,995/15,449 tumor patients of the Radiation Oncology Department in Ulm, Germany, treated between 1981 and 2003, survived at least 1 year after radiotherapy. By long-term follow-up and review of treatment documentation, 100 of them were identified who developed an independent second cancer in or near the irradiated first tumor site. RESULTS: Major primary malignancies were breast cancer (27%), lymphoma (24%), and pelvic gynecologic tumors (17%). Main second tumors were carcinomas of the upper (18%) and lower (12%) gastrointestinal tract, head and neck tumors (10%), lymphoma (10%), breast cancer (9%), sarcoma (9%), and lung cancer (8%). Overall median second tumor latency was 7.4 years (1-42 years). For colorectal cancer it was 3.5 and for leukemia 4.3 years, but for sarcoma 11.7 and for breast cancer 17.1 years. The relatively frequent second tumors of the upper gastrointestinal tract were associated with median radiation doses of 24 Gy. By contrast, second colorectal cancer and sarcoma developed after median doses of 50 Gy. CONCLUSION: The 5- and 15-year probability to develop a histopathologically independent second tumor in or near the irradiated first tumor site, i.e., after intermediate or high radiation doses, was 0.5% and 2.2%, respectively. To identify potentially radiogenic second malignancies, a follow-up far beyond 5 years is mandatory. The incidence and potential dose-response relationship intermediate will be analyzed by a case-case and a case-control study of the Ulm data.

Radiation- and chemoinduced multidrug resistance in colon carcinoma cells.

BACKGROUND AND PURPOSE: Radiation can induce multidrug resistance (MDR) and thus interfere with simultaneous or subsequent chemotherapy. In SW620 colon carcinoma cells, the interrelation of various biological endpoints of MDR was analyzed and the potential of fractionated irradiation and chemoselection to evoke MDR was compared. MATERIAL AND METHODS: To induce/select an MDR phenotype, SW620 were exposed to either 27 Gy in 1.8-Gy daily fractions or to 50% inhibiting concentrations of doxorubicin or cisplatin, given over 6-15 weeks. Expression of genes involved in MDR, including glutathione metabolism, was determined by semiquantitative RT-PCR (reverse transcription-polymerase chain reaction). Efflux was analyzed by flow cytometry after staining with rhodamine-123 or 5-chloromethyl fluorescein diacetate. Apoptosis was monitored after pulse exposure to doxorubicin or cisplatin. Colony-forming assays were performed under continuous drug exposure. RESULTS: A pronounced gene induction was found in MRP2 after cisplatin selection and up to 3 weeks after radiation. LRP was activated only shortly after radiation. Radiation enhanced rhodamine-123 efflux to a similar extent as short-term chemoselection but not as much as long-term drug exposure. Drug-induced apoptosis was slightly delayed in preirradiated cells. Clonogenic growth in the progeny of irradiated cells was less sensitive to cisplatin but not to doxorubicin. CONCLUSION: Fractionated radiation can induce an MDR phenotype in SW620. However, long-term drug exposure establishes a more efficient selection. Various endpoints are not fully concordant regarding the extent of MDR. Posttranscriptional modifications, pleiotropic regulation, and alternative pathways may cause these discrepancies.