Incidence of second malignancies in prostate cancer patients treated with low-dose-rate brachytherapy and radical prostatectomy

Mortality rates in radical cystectomy patients with bladder cancer after radiation therapy for prostate cancer

OBJECTIVE

To conduct a population-based study examining cancer-specific mortality (CSM) and other-cause mortality (OCM) differences in patients with radiation-induced secondary bladder cancer (RT-BCa) vs those with primary bladder cancer (pBCa) undergoing radical cystectomy (RC).

METHODS

Within the Surveillance, Epidemiology, and End Results database (2004-2020), we identified patients with T2-4N0-3M0 bladder cancer treated with RC, who had previously been treated with external beam radiation therapy (EBRT) or brachytherapy for prostate cancer, as well as patients with T2-4N0-3M0 pBCa treated with RC. Cumulative incidence plots and multivariable competing risks regression (CRR) models were used to assess CSM after additional adjustment for OCM. The same methodology was then repeated based on organ-confined (OC: T2N0M0) and non-organ-confined (NOC: T3-4 and/or N1-3) disease.

RESULTS

Of 9957 RC patients, RT-BCa was identified in 347 (3%) compared with 9610 (97%) who had pBCa. In multivariable CRR models, no CSM differences were recorded in the overall comparison (P = 0.8), nor in sub-groups based on OC and NOC disease (P = 0.8 and 0.7, respectively). Conversely, multivariable CRR models identified RT-BCa as an independent predictor of 1.3-fold higher OCM in the overall cohort and of 1.5-fold higher OCM in those with NOC disease. In a sensitivity analysis of patients with NOC disease, EBRT was associated with higher OCM rates (hazard ratio 1.5). By contrast, OCM rates were not different in those with OC disease (P = 0.8).

CONCLUSION

Our study showed that RC for RT-BCa was associated with similar CSM rates as RC for pBCa, regardless of disease stage. However, patients who had undergone EBRT exhibited significantly higher OCM in the NOC sub-group.

[Does radiation therapy for prostate cancer increase the risk of second cancers?]

PURPOSE

The increased risk of second cancer after prostate radiotherapy is a debated clinical concern. The objective of the study was to assess the risk of occurrence of second cancers after prostate radiation therapy based on the analysis the literature, and to identify potential factors explaining the discrepancies in results between studies.

MATERIALS AND METHODS

A review of the literature was carried out, comparing the occurrence of second cancers in patients all presenting with prostate cancer, treated or not by radiation.

RESULTS

This review included 30 studies reporting the occurrence of second cancers in 2,112,000 patients treated or monitored for localized prostate cancer, including 1,111,000 by external radiation therapy and 103,000 by brachytherapy. Regarding external radiation therapy, the average follow-up was 7.3years. The majority of studies (80%) involving external radiation therapy, compared to no external radiation therapy, showed an increased risk of second cancers with a hazard ratio ranging from 1.13 to 4.9, depending on the duration of the follow-up. The median time to the occurrence of these second cancers after external radiotherapy ranged from 4 to 6years. An increased risk of second rectal and bladder cancer was observed in 52% and 85% of the studies, respectively. Considering a censoring period of more than 10 years after irradiation, 57% and 100% of the studies found an increased risk of rectal and bladder cancer, without any impact in overall survival. Studies of brachytherapy did not show an increased risk of second cancer. However, these comparative studies, most often old and retrospective, had many methodological biases.

CONCLUSION

Despite numerous methodological biases, prostate external radiation therapy appears associated with a moderate increase in the risk of second pelvic cancer, in particular bladder cancer, without impacting survival. Brachytherapy does not increase the risk of a second cancer.

Secondary bladder and colorectal cancer after treatments for prostate cancer: A population based study

BACKGROUND

Prostate cancer (PCa) patients receiving radiotherapy may be predisposed to secondary malignancies. This study aimed to determine the association between PCa treatments, including radical prostatectomy (RP), external beam radiation therapy (EBRT), brachytherapy (BT) and androgen deprivation therapy (ADT); and secondary bladder and colorectal cancer.

METHODS

A cohort study was constructed using Quebec administrative databases (Med-Echo and RAMQ). Included men were diagnosed and treated for PCa between 2000 and 2016. Patients with bladder or colorectal cancer prior to PCa were excluded. Follow-up ended at the earliest of the following: incidence of bladder or colorectal cancer, death, or December 31, 2016. EBRT, BT, EBRT+ADT, RP + ADT or ADT only were compared individually to RP. The incidence of secondary bladder and colorectal cancer were computed. Inverse probability of treatment weighting (IPTW) based on a propensity score was used to control for potential confounding. IPTW-Cox proportional hazards models were used.

RESULTS

A significant association was found between secondary bladder cancer and EBRT (HR: 1.84, 95%CI: 1.60;2.13), and also EBRT+ADT (HR: 2.08, 95%CI: 1.67;2.56), but not with BT (HR: 1.36, 95%CI: 0.68;2.74). Secondary colorectal cancer was significantly associated to either EBRT (HR: 1.36, 95%CI: 1.21;1.53); or BT (HR: 2.46, 95%CI: 1.71;3.54). The association between ADT alone and both secondary cancers was also significant (HR: 1.98, 95%CI: 1.69;2.31 and HR: 1.69, 95%CI: 1.49;1.92, respectively).

CONCLUSIONS

Compared to PCa patients undergoing RP, the secondary bladder cancer was associated with EBRT, ADT, alone or in combination. The secondary colorectal cancer was also associated with receiving either EBRT, BT or ADT.

Prostate radiotherapy and the risk of secondary rectal cancer-a meta-analysis

PURPOSE

Radiotherapy is being used increasingly in the treatment of prostate cancer. However, ionising radiation may confer a small risk of a radiation-induced secondary malignancy. We aim to assess the risk of rectal cancer following pelvic radiotherapy for prostate cancer.

METHODS

A search was conducted of the PubMed/MEDLINE, EMBASE and Web of Science databases identifying studies reporting on the risk of rectal cancer following prostatic radiotherapy. Studies must have included an appropriate control group of non-irradiated prostate cancer patients. A meta-analysis was performed to assess the risk of prostatic radiotherapy on subsequent rectal cancer diagnosis.

RESULTS

In total, 4757 articles were screened with eight studies meeting the predetermined criteria. A total of 796,386 patients were included in this meta-analysis which showed an increased odds ratio (OR) for subsequent rectal cancer in prostate cancer patients treated with radiotherapy compared to those treated by non-radiotherapy means (OR 1.45, 1.07-1.97, p = 0.02).

CONCLUSION

These findings confirm that prostate radiotherapy significantly increases the risk of subsequent rectal cancer. This risk has implications for treatment selection, surveillance and patient counselling. However, it is crucial that this information is presented in a rational and comprehensible manner that does not disproportionately frighten or deter patients from what might be their most suitable treatment modality.

Does radiotherapy increase the risk of colorectal cancer among prostate cancer patients? A large population-based study

Objective: The survival of prostate cancer (PC) patients after radiotherapy (RT) has improved over time, but it raises the debate of increased risk of secondary colorectal cancer (SCRC). This study aimed to assess whether RT for PC treatment increases the risk of SCRC in comparison with radical prostatectomy (RP). Methods: A population-based cohort of PC patients treated only with RT or only with RP between January 2007 and December 2015 was identified from the Taiwan Cancer Registry. The incidence rate of SCRC development was estimated using Cox regression model. Results: In this study, total 8,797 PC patients treated with either RT (n = 3,219) or RP (n =5,578). Patients subjected to RT were elder (higher percentage of 70≧years, p < 0.0001) and more advanced clinically (stage III: 22.90% vs. 11.87%; stage IV: 22.15% vs. 13.80%, p < 0.0001), compared to those subjected to RP. More patients subjected to RT had a much higher percentage of autoimmune disease (22.34% vs. 18.75%, p < 0.0001) and osteoarthritis and allied disorders (16.31% vs. 12.98%, p < 0.0001). Besides, RT patients had a higher percentage of underlying Crohn's disease (0.25% vs. 0.05%, p = 0.0230). Although almost all selected factors were not statistically significant, they presented the positive risk of SCRC for those under RP compared with those among RT. Besides, for PC patients in clinical stage I and II, patients with RP may have borderline significantly protective effects of SCRC compared with those under RT (stage I, HR: 0.14; 95% C.I.:0.01-1.39; p = 0.0929; stage II, HR: 1.92; 95% C.I.:0.93-3.95; p = 0.0775). Kaplan-Meier curves for a 3-year-period, which demonstrated no statistical difference in the risk of SCRC free between PC patients undergoing RT and RP (p = 0.9766). Conclusion: Whether or not pelvic RT for PC is associated with an increased risk for SCRC on a population-based level remains a matter of considerable debate. From a clinical perspective, these PC survivors should be counseled accordingly and received continued cancer surveillance with regular colonoscopy follow-up.

Incidence of subsequent primary cancers and radiation-induced subsequent primary cancers after low dose-rate brachytherapy monotherapy for prostate cancer in long-term follow-up

BACKGROUND

As aging is the most significant risk factor for cancer development, long-term prostate cancer (PCa) survivors have an evident risk of developing subsequent primary cancers (SPCs). Radiotherapy itself is an additional risk factor for cancer development and the SPCs appearing beyond 5 years after radiotherapy in the original treatment field can be considered as radiation-induced subsequent primary cancers (RISPCs).

METHODS

During the years 1999-2008, 241 patients with localized PCa who underwent low dose-rate brachytherapy (LDR-BT) with I125 and were followed-up in Kuopio University Hospital, were included in this study. In this study the incidences and types of SPCs and RISPCs with a very long follow-up time after LDR-BT were evaluated.

RESULTS

During the median follow-up time of 11.4 years, a total of 34 (14.1%) patients developed a metachronous SPC. The most abundant SPCs were lung and colorectal cancers, each diagnosed in six patients (16.7% out of all SPCs). The crude incidence rate of RISPC was 1.7% (n = 4). Half of the SPC cases (50%) were diagnosed during the latter half of the follow-up time as the risk to develop an SPC continued throughout the whole follow-up time with the actuarial 10-year SPC rate of 7.0%. The crude death rates due to metachronous out-of-field SPCs and RISPCs were 50 and 50%, respectively.

CONCLUSION

The crude rate of SPC was in line with previously published data and the incidence of RISPC was very low. These results support the role of LDR-BT as a safe treatment option for patients with localized PCa.

Therapeutic efficacy of TACE 125I seed implantation and its combination with intra-tumor injection of cisplatin for the treatment of hepatocellular carcinoma

Background

This study aimed to compare the therapeutic efficacy of transcatheter arterial chemoembolization (TACE) combined with either ¹²⁵I seed implantation or ¹²⁵I seed implantation and intra-tumor injection of cisplatin in treating hepatocellular carcinoma (HCC).

Methods

A total of 100 patients with HCC were analyzed. The control group (n = 50) received TACE combined with ¹²⁵I seed implantation therapy. The therapy group (n = 50) was treated with an intra-tumor injection of cisplatin along with TACE and ¹²⁵I seed implantation therapy. After treatment, routine blood, liver and kidney function, tumor volume, T lymphocyte subset count (CD3, CD4, and CD8), implanted metastases, and survival were studied.

Results

The tumor volume decreased by 27.4% on average in the control group, and by 38.6% in the therapy group. Alpha fetoprotein (AFP) level decreased in all cases, and it was significantly lower in the therapy group than in the control group. Remote metastasis was observed in both groups (7 in the control group and 3 in the therapy group). No significant difference in routine blood, liver and kidney function, and T-lymphocyte subset counts were found between the two groups. Eight patients died of metastases in the control group and 2 in the therapy group at 1-year follow-up (P < 0.05).

Conclusion

TACE combined with either ¹²⁵I seed implantation or ¹²⁵I seed implantation and intra-tumor injection of cisplatin was effective for the treatment of HCC. Of the 2 combination therapies, TACE combined with ¹²⁵I seed implantation and intra-tumor injection of cisplatin was more effective for the treatment of HCC.

Long-Term Management of Incidental Bladder Cancer Detected in Patients Undergoing Prostatectomy for Prostate Cancer

INTRODUCTION

At our institution, screening for incidental bladder cancer is routinely performed to avoid tumor cell dissemination caused by surgery in patients undergoing prostatectomy for prostate cancer (PCa). Here, we report the long-term clinical results in patients with incidental bladder cancer detected by routine screening prior to prostatectomy.

MATERIALS AND METHODS

Between January 2003 and December 2013, 430 patients undergoing prostatectomy for resection of PCa were enrolled in this cohort study. All patients underwent screening with cystoscopy, urinary sediment analysis, and urinary cytology to detect incidental bladder cancer. The clinical outcomes of cases with incidental bladder cancer were evaluated.

RESULTS

The incidence of incidental bladder cancer was 2.1% (9/430). All tumors were single papillary tumors located around the urinary orifice or lateral side and were diagnosed as urothelial cancer (UC). No significant findings were detected by urinary sediment analysis or urinary cytology. Pathological results of transurethral resections revealed 5 cases of pTa with Grade 1 UC and 4 cases of pTa with Grade 2 UC. Androgen-deprivation therapy was administered to 8/9 patients. During the observation period (average of 7.2 years), UC recurrence was detected in 2 cases (2 and 7.3 years). However, transurethral resection successfully removed the tumor completely. After an average of 19.6 months (12-25 months) without UC recurrence, 7 patients (77.8%) underwent prostatectomy, and 2 patients received radiation or androgen-deprivation therapy. Prostatectomy was carried out without dissemination of UC during the observation period.

CONCLUSION

Incidental UC was detected in 2.1% of prostatectomy candidates. Preoperative routine screening with flexible cystoscopy was useful to detect early incidental UC.

Long-term incidence of secondary bladder and rectal cancer in patients treated with brachytherapy for localized prostate cancer: a large-scale population-based analysis

OBJECTIVE

To examine the incidence and time trends of secondary bladder cancer (BCa) and rectal cancer (RCa) after brachytherapy (BT) relative to radical prostatectomy (RP).

MATERIALS AND METHODS

Within the Surveillance, Epidemiology and End Results (SEER) database (1988-2015), we identified patients with localized PCa as an only or first primary cancer, who underwent BT or RP. Cumulative incidence plots and multivariable competing-risks regression (CRR) models were used. Sensitivity analyses focused on patients' age and year of diagnosis intervals and tested the effect of an unmeasured confounder.

RESULTS

Of 318 058 patients with localized prostate cancer (PCa), 55 566 (18.4%) underwent BT. After propensity score-matching, 20-year secondary BCa incidence was 6.0% in patients who had undergone BT vs 2.4% in those who had undergone RP (P < 0.001) and the respective 20-year secondary RCa incidence was 1.1% vs 0.5% (P < 0.001). In multivariable CRR models, BT predicted higher secondary BCa (hazard ratio [HR] 1.58; P < 0.001) and RCa rates (HR 1.59; P < 0.001) vs RP. Sensitivity analyses replicated the same results after stratification according to age and showed HRs of decreasing magnitude for historical, intermediate and contemporary years of diagnosis. An unmeasured confounder with an HR of 2 would render the effect of BT statistically insignificant if it affected patients in the RP group with a ratio of 2 relative to those in the BT group. Finally, temporal trends showed a decrease of secondary 5-year BCa and RCa rates.> CONCLUSIONS: Brachytherapy predominantly increases the risk of secondary BCa and, to a lesser extent, that of RCa. Follow-up of such patients is therefore required. It is encouraging that both secondary BCa, and RCa rates, in particular, have recently decreased, RCa.

Iatrogenic Disease of the Genitourinary Tract

Iatrogenic disease is defined as illness caused by diagnostic procedures or treatment given by health care professionals. More recently described treatment complications involving the genitourinary tract include newly recognized variants of renal carcinoma in the setting of dialysis/end-stage renal disease, treatment effect in genitourinary carcinomas, and medical renal disease caused by drug therapies, including immunotherapy. The objective of this review is to cover iatrogenic inflammatory diseases, pseudotumors and tumors of the kidney, bladder, prostate, testis and paratestis of most interest to surgical pathologists. For this reason, disease caused by the following will not be covered: iatrogenic glomerulonephritis, self-inflicted injury including the introduction of foreign bodies, surgical error, drugs of abuse and herbal medications, and iatrogenic disease in the transplant setting including ischemia/reperfusion injury. Emphasis is placed upon commonly encountered diseases in order to ensure that the review is of utility to practicing pathologists. The clinical context, pathophysiology and histopathology of each disease entity are covered.

Rectal adenocarcinoma with rectoprostatic fistula following prostate brachytherapy

An 80-year-old man with history of prostate cancer successfully treated with brachytherapy was initially thought to have Fournier's gangrene until imaging detected a rectoprostatic fistula. Although this is known to be a rare complication of prostate brachytherapy, in this case the aetiology was a new primary rectal adenocarcinoma. It was not possible to catheterise per urethra owing to the fistula, so he was fitted with suprapubic catheter, and underwent palliative loop colostomy. Brachytherapy carries a low risk of second primary cancers, although two previous cases reported such cancers as radiation induced. This is, to our knowledge, the first case of rectal adenocarcinoma following prostate brachytherapy in the literature.

High prevalence of secondary bladder cancer in men on radiotherapy for prostate cancer: evidence from a meta-analysis

Objective

To assess whether radiotherapy (RT) for prostate cancer (PCa) was a risk factor for secondary bladder cancer (BLCa) through a meta-analysis.

Materials and methods

The MEDLINE, Embase, and the Cochrane Library were systematically searched for all studies investigating the risk of BLCa in patients with RT. The association between RT and risk of BLCa was summarized using hazard ratio with a 95%CI. The protocol for this meta-analysis is available from PROSPERO (CRD42018090075).

Results

Overall, 619,479 participants (age: 57-79 years) were included from 15 studies, 206,852 of whom were patients who received RT. Synthesis of results indicated that RT was significantly associated with an increased risk of BLCa compared with the risk in those who received radical prostatectomy or non-RT (overall HR=1.6, 95%CI: 1.33-1.92, P<0.001). The results were consistent when restricted to a 5-year lag period (HR=1.84, 95%CI: 1.26-2.69, P=0.002) and multivariable adjustment (HR=1.96, 95%CI: 1.47-2.62, P<0.001), but not for 10-year lag period (HR=1.93, 95%CI: 0.9- 4.16, P=0.093) and brachytherapy subgroup (HR=1.33, 95%CI: 0.87-2.05, P=0.188). The GRADE-profiler revealed that the rate of events of BLCa on average in the RT-patients and the non-RT control was 2,462/183,669 (1.3%) and 4,263/382,761(1.1%), respectively; the overall quality of the evidence was low.

Conclusion

Patients who received RT for PCa was associated with higher risks of developing secondary BLCa compared to those unexposed to RT, but the absolute effect was low.

Incidence of second tumours in high risk prostate cancer patients according to the primary treatment applied

INTRODUCTION AND OBJECTIVES

The onset of second primary tumours should be considered in high-risk prostate cancer patients in the natural course of the disease. Our aim was to evaluate the influence of primary treatment with curative intent for these patients on the development of second primary tumours.

MATERIAL AND METHODS

A retrospective study of 286 patients diagnosed between 1996 and 2008, treated by radical prostatectomy (n=145) or radiotherapy and androgen blockade (n=141). The homogeneity of both series was analysed using the Chi-squared test for the qualitative variables, and the Student's t-test for the quantitative variables. A multivariate Cox regression analysis was performed to assess whether the type of primary treatment influenced the development of second tumours.

RESULTS

The median age was 66 years, and the median follow-up was 117.5 months. At the end of follow-up, 60 patients (21%) had developed a second primary tumour. In the prostatectomy group it was located in the pelvis in 13 (9%) cases, and those treated with radiotherapy and hormonotherapy in 8 (5.7%) cases (P=.29). The most common organ sites were: colo-rectal in 17 (28.3%) patients, the lung in 11 (18.3%), and the bladder in 6 (10%) patients. In the multivariable analysis, the risk of a second tumour doubled for those treated with radiotherapy and hormonotherapy (HR=2.41, 95%CI: 1.31-4.34, P=.005) compared to the patients treated by prostatectomy. Age and rescue radiotherapy did not behave as independent predictive factors.

CONCLUSIONS

The onset of a second primary tumour was related with the primary treatment given; thus the risk for those treated with radiotherapy and androgen deprivation therapy more than doubled.

The impact of age at the time of radiotherapy for localized prostate cancer on the development of second primary malignancies

PURPOSE

There is a known increased risk of second primary malignancy (SPM) in patients with prostate cancer (CaP) treated with radiotherapy (RT). It is unclear how age at diagnosis influences the risk of SPMs.

MATERIALS AND METHODS

Using the 1973 to 2013 Surveillance, Epidemiology, and End Results Program, we studied the impact of age on SPMs (defined as a bladder or rectal tumor) after localized CaP treatment with radical prostatectomy (RP) or RT. SPM risk was compared using inverse probability of treatment weighting (IPTW)-adjusted cumulative incidence function and competing-risk proportional hazard models. Overall survival (OS) in patients with SPM was compared using Kaplan Meier and Cox regression analyses.

RESULTS

A total of 579,608 patients met inclusion criteria, and 51.8% of the cohort was treated with RT. The 10- and 20-year cumulative incidences of competing risk (IPTW adjusted) of SPMs were 1.9% (95%CI = 1.8-1.9%) and 3.6% (95%CI = 3.4-3.7%) after RP vs. 2.7% (95%CI = 2.6-2.8%) and 5.4%(95%CI = 5.3-5.6%) after RT. IPTW-adjusted competing risk hazard ratio (HR) of SPM after RT compared to RP was increased in the entire cohort (HR 1.46; 95%CI = 1.39-1.53, P < 0.001) and was highest in the youngest patients: Age <55 HR = 1.83 (95% confidence interval [CI] = 1.49-2.24, P<0.001), Age 55 to 64 HR = 1.66 (95%CI = 1.54-1.79, P < 0.001), Age 65-74 HR = 1.41 (95%CI = 1.33-1.48, P < 0.001), Age ≥75 HR = 1.14 (95%CI = 0.97-1.35, P = 0.112). At 10 years, SPM-specific mortality occurred in 28.9% of patients treated with RT, though OS with SPM was worse in the youngest patients: Age <55 HR = 1.88 (95%CI = 1.25-2.81, P = 0.002), Age 55-64 HR = 1.60 (95%CI = 1.42-1.81, P < 0.001), Age 65-74 HR = 1.40 (95%CI = 1.30-1.52, P < 0.001), Age ≥ 75 HR = 1.27 (95%CI = 1.06-1.53, P = 0.009). All of the age categories had similar median follow-up times.

CONCLUSION

At 10 years there is a 1.8% increased incidence of SPM after RT compared to RP, of which <30% of RT-treated patients with an SPM die as a result of a SPM. However, the risk of SPMs was greatest among younger men treated with RT for localized CaP, and this relationship could not be explained solely by follow-up time, latency time, or life expectancy. An improved understanding of those at the highest risk of SPMs may help tailor treatment and surveillance strategies.

Low dose rate prostate brachytherapy

Low dose rate (LDR) prostate brachytherapy is an evidence based radiation technique with excellent oncologic outcomes. By utilizing direct image guidance for radioactive source placement, LDR brachytherapy provides superior radiation dose escalation and conformality compared to external beam radiation therapy (EBRT). With this level of precision, late grade 3 or 4 genitourinary or gastrointestinal toxicity rates are typically between 1% and 4%. Furthermore, when performed as a same day surgical procedure, this technique provides a cost effective and convenient strategy. A large body of literature with robust follow-up has led multiple expert consensus groups to endorse the use of LDR brachytherapy as an appropriate management option for all risk groups of non-metastatic prostate cancer. LDR brachytherapy is often effective when delivered as a monotherapy, although for some patients with intermediate or high-risk disease, optimal outcome are achieved in combination with supplemental EBRT and/or androgen deprivation therapy (ADT). In addition to reviewing technical aspects and reported clinical outcomes of LDR prostate brachytherapy, this article will focus on the considerations related to appropriate patient selection and other aspects of its use in the treatment of prostate cancer.

Secondary Urethral Malignancies Following Prostate Brachytherapy

OBJECTIVE

To understand urethral secondary malignancies among patients treated with brachytherapy (BRT) for primary prostate cancer.

PATIENTS AND METHODS

Institutional retrospective review identified 13 patients evaluated from 2003 to 2014 with urethral cancer and history of BRT monotherapy for prostate cancer. All patients were biochemically free of their primary disease and radiation-associated secondary malignancies (RASMs) were confirmed pathologically to be histologically distinct from primary tumor. BRT characteristics, patient age, presentation, staging workup, and clinical course were evaluated.

RESULTS

The mean time from BRT to presenting symptoms of hematuria, urinary retention, and/or renal failure was 71 months. Symptom onset to RASM diagnosis interval was 24 months. Mean time from BRT to RASM diagnosis was 95 months. Eighty-five percent of patients had an undetectable prostate-specific antigen level (<0.2 ng/mL) at last follow-up. Types of RASM included sarcomatoid carcinoma (6), small cell carcinoma (2), urothelial carcinoma with squamous differentiation (2), squamous cell carcinoma (1), rhabdomyosarcoma (1), and urothelial carcinoma (1). A majority of patients were diagnosed with advanced disease with either distant metastases (54%) or local progression (23%). Ten patients died during this study period with median time to death after RASM diagnosis of 6 months.

CONCLUSION

RASMs localized to the posterior urethra displayed advanced disease and high mortality rates. Refractory lower urinary tract symptoms, hematuria, and history of prostate BRT should raise suspicion for urethral RASMs. Further studies are warranted to determine patient and disease characteristics that correlate with disease-specific mortality of secondary urethral malignancies.

Second malignancies after permanent implant prostate cancer brachytherapy: A single-institution study of 675 patients treated between 1999 and 2003

PURPOSE

To analyse the rate of secondary malignancies observed in a series of 675 prostate cancer patients who underwent a permanent implant brachytherapy between 1999 and 2003, and to compare the incidence with the expected rate in a matched general French population.

MATERIAL AND METHODS

The cohort included low-risk patients and a selection of "favourable-intermediate" risk patients. All patients were homogeneously treated using an intraoperative dynamic planning prostate brachytherapy technique, with loose 125-iodine seeds and a prescription dose of 145Gy. The mean follow-up was 132 months.

RESULTS

The 10-year overall survival for the entire cohort was 92% (95% confidence interval [CI]: 90-94). The 10-year relapse-free survival rate was 82% (95% CI: 79-85). Overall, 61 second cancers were registered. When comparing with a matched general French population, the standard incidence ratio (SIR) for bladder cancer was 1.02 (95% CI: 0.46-1.93). For colorectal cancer, the SIR was 0.45 (95% CI: 0.19-0.89). For lung cancer, the SIR was 0.38 (95% CI: 0.17-0.76). The SIR for all cancers was 0.61 (95% CI: 0.47-0.79). When excluding secondary colorectal and lung cancers (both with low SIRs in this series), the SIR for all cancers was 1.06 (95% CI: 0.77-1.29).

CONCLUSION

With a mean follow-up of more than 11 years, this series does not detect any excess risk of second cancers associated with permanent implant prostate brachytherapy. However, due to power limitation, a small increase in the risk of secondary malignancies cannot be totally ruled out.

Institutional long-term outcomes at the first Canadian center performing intraoperatively planned low-dose-rate brachytherapy alone in low- and intermediate-risk prostate cancer

PURPOSE

The aim of this study is to report the long-term outcomes and toxicities from a large cohort of patients with localized prostate cancer treated with low-dose-rate intraoperatively planned brachytherapy.

METHODS AND MATERIALS

Prostate-specific antigen levels, urinary symptoms, and erectile function were recorded at baseline, and each followup visit was then entered into a prospective database. Urinary toxicity requiring procedural intervention was retrospectively verified using an integrated electronic medical system. A separate cross-sectional survey was performed to measure postimplant sexual function.

RESULTS

A total of 822 patients with low and favorable intermediate-risk prostate cancer were treated at our institution between 2003 and 2013. The Kaplan-Meier estimates for biochemical recurrence for our cohort were 95% and 87% at 5 and 10 years, respectively. Cystoscopy, transurethral resection of prostate, or dilatation was required for 7.1% of 720 patients with more than 2 years of followup. At a median followup of 3.7 years, 64.4% of patients retained adequate erectile function for intercourse, with 54% of patients who were no longer sexually active postimplant reporting social factors as the primary reason.

CONCLUSIONS

Our institutional experience with intraoperative low-dose-rate prostate brachytherapy yielded excellent long-term results with a low incidence of urinary and sexual toxicity.

Pattern of solid and hematopoietic second malignancy after local therapy for prostate cancer

BACKGROUND AND PURPOSE

Second malignancies (SM) after external beam radiotherapy (EBRT) or brachytherapy (BT) for prostate cancer (PCa) are rare but serious sequelae.

MATERIALS AND METHODS

The Surveillance, Epidemiology, and End Results (SEER) database was used to identify men diagnosed with cT1-2N0M0 PCa between 1999 and 2005, who underwent EBRT, BT or radical prostatectomy (RP). Patients with time interval to second malignancy or follow-up shorter than five and two years were excluded for solid and hematopoietic SM analyses respectively. Risks for solid and hematopoietic SM were evaluated via the multivariate Fine and Gray proportional hazards model.

RESULTS

EBRT and BT resulted in similar increases in solid and hematopoietic SM compared to RP. In subgroup analysis stratified by treatment modality, only the EBRT cohort demonstrated significantly decreased solid and hematopoietic SM in years 2002-2005 compared to years 1999-2001, with adjusted-hazard ratios of 0.752 (p=0.001) and 0.815 (p=0.018) respectively.

CONCLUSIONS

EBRT and BT resulted in statistically equivalent increase in both solid and hematopoietic SM compared to RP. EBRT in more recent years resulted in significantly decreased solid and hematopoietic SM, coinciding with increased utilization of IMRT.

Risk of second cancer following radiotherapy for prostate cancer: a population-based analysis

Background

To investigate the risk of second cancer and radiation induced second cancer following prostate cancer radiotherapy.

Methods

We compared men with radiotherapy only with those treated with radical prostatectomy only and those with radiotherapy after radical prostatectomy. Cumulative incidences of second cancers were calculated. Cox analyses were performed to identify determinants influencing second cancer incidence.

Results

Nineteen thousand five hundred thirty eight patients were analyzed. Age and median follow-up differed significantly with radiotherapy only patients having the highest median age (70.3 years) and radical prostatectomy only patients the longest median follow-up (10.2 years). Ten-year cumulative incidence of second cancer was 15.9%, 13.2% and 10.5% for patients with radiotherapy only, radiotherapy after radical prostatectomy and radical prostatectomy only (p <0.0001). Increasing age and belonging to the radiotherapy only group were associated with a higher risk of second cancer—no significant increase was seen in radiotherapy after radical prostatectomy patients. A significantly higher rate of smoking related malignancies, like lung, bladder and non-melanoma skin cancer, was seen in radiotherapy only patients.

Conclusions

No clear increase in radiation induced second cancer was found in patients after radiotherapy for prostate cancer. Whereas the rate of second cancer was increased in radiotherapy only patients, no such increase was seen in patients with radiotherapy after radical prostatectomy. The increase of second cancer following radiotherapy only is highly likely to reflect advanced age and lifestyle habits and comorbidities.

[Second neoplasms after percutaneous radiotherapy]

Radiation therapy represents an alternative treatment to radical prostatectomy in the management of clinically localized prostate cancer. Radiation-induced second neoplasms are defined by a latency period of at least 5 years, location within the field of radiation therapy, and a histology which differs from the primary tumor. Based on the data in the literature, there is a consistently increased risk of bladder cancer (HR: 1.67, 95% CI 1.55-1.80), rectal cancer (HR: 1.79, 95% CI 1.34-2.38), and colorectal cancer (HR: 1.79, 95% CI 1.34-23.8) following percutaneous radiation therapy. Following brachytherapy only an increased for the development of bladder cancer (HR: 2.14, 95% CI 1.03-3.94) has been observed. The incidence of second neoplasms increases significantly and continuously with the posttreatment time interval. Although bladder cancers following RT of the prostate are usually more locally advanced and of high grade, no negative impact in terms of overall survival and cancer-specific survival has been observed. Symptoms or findings of microhematuria need to be examined thoroughly after radiation therapy to identify bladder cancer quite early.

Secondary Cancers After Radiation Therapy for Primary Prostate or Rectal Cancer

Literature about the risk of secondary cancer after radiation therapy (RT) of prostate and rectal cancer reveals contradictory results. We conducted a meta-analysis to examine whether the RT induces secondary rectal or prostate cancer in patients, respectively, with prostate or rectal cancer. All studies published in Medline or Pubmed up to March 3, 2015, containing RT of primary rectal or prostate cancer, and providing risk estimates of secondary prostate or rectal cancer were considered as eligible. Relative risk (RR) and standardized incidence ratios (SIR) were calculated using the random-effects model. Twenty studies met the inclusion criteria. 12 of them were from the Surveillance, Epidemiology, and End Results (SEER) database. For prostate cancer patients, pooled adjusted RRs or SIRs did not show an effect on the risk of secondary rectal cancer. However, notwithstanding the limitations of SEER-based studies, the subgroup of prostate cancer patients receiving external beam radiation therapy (EBRT) showed an increased risk of rectal cancer. For rectal cancer patients, pooled adjusted RR of prostate cancer was 1.12 (95 % CI, 0.44-2.8) and SIR was 0.40 (95 % CI, 0.29-0.55). All studies included in the SIR analysis of rectal cancer were derived from the SEER data source. Based on current evidence, RT for prostate cancer patients had no effect on rectal cancer incidence, except for patients who received EBRT therapy. However, compared with the general population, RT for rectal cancer is associated with a decreased prostate cancer risk as found in SEER-based studies.

The risk of second malignancies after 125I prostate brachytherapy as monotherapy in a single Australian institution

PURPOSE

To report the incidence of second primary cancer (SPC) after ¹²⁵I brachytherapy (BT) for early prostate cancer in an Australian institution.

METHODS AND MATERIALS

All the patients in our cohort had a cystoscopy before the implant. Data were prospectively collected on all subsequent SPC diagnoses. Standardized incidence ratios (SIRs) were calculated to compare data with the Australian population. Kaplan-Meier analysis was used to determine the actuarial second malignancy and pelvic malignancy rates and the death from SPC and from any cause.

RESULTS

A total of 889 patients were followed up for a median of 4.16 (0-13) years with 370 (42%) patients having ≥5 years of followup. Sixty patients subsequently developed an SPC of which 11 were pelvic malignancies. The 5- and 10-year cumulative incidences were 1.3% (95% confidence interval [CI]: 0.6-3) and 3.3% (95% CI: 1-7) for any pelvic malignancy and 1% (95% CI: 0.4-2) and 2.6% (1-6) for bladder cancer, respectively. The SIR was significantly higher than expected for all bladder cancers at 2.9 (95% CI: 1-6) and close to significance (SIR, 3.0; 95% CI: 0.97-7) for bladder cancers within the first 5 years of followup in the subgroup analysis. On multivariate analysis, older age was associated with increased SPC risk and older age and positive smoking status were associated with increased overall mortality, mortality due to SPC, and mortality from second malignancy (p < 0.05).

CONCLUSIONS

There may be a small increased risk of bladder SPC after prostate BT. A tendency toward a higher risk of bladder SPC after BT was found within the first 5 years of followup probably reflecting screening bias.

[Current situation and perspectives of proton therapy]

Proton beam therapy is indicated as a treatment for some rare tumours and paediatric tumours because the technique allows a good local control with minimal toxicity; the growing number of centres that use proton beam therapy is associated with an increase of dosimetric and clinical data for other malignant tumours as well. This paper reviews potential indications of proton beam therapy. A systematic review on Medline was performed with the following keywords proton beam therapy, cancer, heavy particle, charged particle. No phase III trial has been published using proton beam therapy in comparison with the best photon therapy, but numerous retrospective and dosimetric studies have revealed an advantage of proton beam therapy compared to photons, above all in tumours next to parallel organs at risk (thoracic and abdominal tumours). This could be accompanied with a better safety profile and/or a better tumoural control; numerous phase 0, I, II, III and IV studies are ongoing to examine these hypotheses in more common cancers. Use of proton beam therapy is growing for common cancers within clinical trials but some indications could be applied sooner since in silico analysis showed major advantages with this technique.

Late rectal toxicity after low-dose-rate brachytherapy: incidence, predictors, and management of side effects

As clinical outcomes for patients with clinically localized prostate cancer continue to improve, patients and physicians are increasing making treatment decisions based on concerns regarding long-term morbidity. A primary concern is late radiation proctitis, a clinical entity embodied by various signs and symptoms, ranging from diarrhea to rectal fistulas. Here, we present a comprehensive literature review examining the clinical manifestations and pathophysiology of late radiation proctitis after low-dose-rate brachytherapy (BT), as well as its incidence and predictors. The long-term risks of rectal bleeding after BT are on the order of 5-7%, whereas the risks of severe ulceration or fistula are on the order of 0.6%. The most robust predictor appears to be the volume of rectum receiving the prescription dose. In certain situations (e.g., salvage setting, for patients with increased radiosensitivity, and following aggressive biopsy after BT), the risk of these severe toxicities may be increased by up to 10-fold. A variety of excellent management options exist for rectal bleeding, with endoscopic methods being the most commonly used.