Radiotherapy after Radical Prostatectomy: Treatment Recommendations Differ between Urologists and Radiation Oncologists

Purpose

There is no consensus on optimal use of radiotherapy following radical prostatectomy. The purpose of this study was to describe opinions of urologists and radiation oncologists regarding adjuvant and salvage radiotherapy following radical prostatectomy.

Methods

Urologists and genitourinary radiation oncologists were solicited to participate in an online survey. Respondent characteristics included demographics, training, practice setting, patient volume/experience, and access to radiotherapy. Participant practice patterns and attitudes towards use of adjuvant and salvage radiotherapy in standardized clinical scenarios were assessed.

Results

One hundred and forty-six staff physicians participated in the survey (104 urologists and 42 genitourinary radiation oncologists). Overall, high Gleason score (Gleason 7 vs. 6, RR 1.37 95% CI 1.19-1.56, p<0.0001 and Gleason 8-10 vs. 6, RR 1.56 95% CI 1.37-1.78, p<0.0001), positive surgical margin (RR 1.43 95% CI 1.26-1.62, p<0.0001), and extraprostatic tumour extension (RR 1.16 95% CI 1.05-1.28, p<0.002) conferred an increased probability of recommending adjuvant radiotherapy. Radiation oncologists were more likely to recommend adjuvant radiotherapy across all clinical scenarios (RR 1.48, 95% CI 1.39, 1.60, p <0.001). Major differences were found for patients with Gleason 6 and isolated positive surgical margin (radiotherapy selected by 21% of urologists vs. 70% of radiation oncologists), and patients with extraprostatic extension and negative surgical margins (radiotherapy selected by 18% of urologist vs. 57% of radiation oncologists).

Conclusions

Urologists and radiation oncologists frequently disagree about recommendation for post-prostatectomy adjuvant radiotherapy. Since clinical equipoise exists between adjuvant versus early salvage post-operative radiotherapy, support of clinical trials comparing these approaches is strongly encouraged.     

A Novel MiRNA-Based Predictive Model for Biochemical Failure Following Post-Prostatectomy Salvage Radiation Therapy

Purpose

To develop a microRNA (miRNA)-based predictive model for prostate cancer patients of 1) time to biochemical recurrence after radical prostatectomy and 2) biochemical recurrence after salvage radiation therapy following documented biochemical disease progression post-radical prostatectomy.

Methods

Forty three patients who had undergone salvage radiation therapy following biochemical failure after radical prostatectomy with greater than 4 years of follow-up data were identified. Formalin-fixed, paraffin-embedded tissue blocks were collected for all patients and total RNA was isolated from 1mm cores enriched for tumor (>70%). Eight hundred miRNAs were analyzed simultaneously using the nCounter human miRNA v2 assay (NanoString Technologies; Seattle, WA). Univariate and multivariate Cox proportion hazards regression models as well as receiver operating characteristics were used to identify statistically significant miRNAs that were predictive of biochemical recurrence.

Results

Eighty eight miRNAs were identified to be significantly (p<0.05) associated with biochemical failure post-prostatectomy by multivariate analysis and clustered into two groups that correlated with early (≤ 36 months) versus late recurrence (>36 months). Nine miRNAs were identified to be significantly (p<0.05) associated by multivariate analysis with biochemical failure after salvage radiation therapy. A new predictive model for biochemical recurrence after salvage radiation therapy was developed; this model consisted of miR-4516 and miR-601 together with, Gleason score, and lymph node status. The area under the ROC curve (AUC) was improved to 0.83 compared to that of 0.66 for Gleason score and lymph node status alone.

Conclusion

miRNA signatures can distinguish patients who fail soon after radical prostatectomy versus late failures, giving insight into which patients may need adjuvant therapy. Notably, two novel miRNAs (miR-4516 and miR-601) were identified that significantly improve prediction of biochemical failure post-salvage radiation therapy compared to clinico-histopathological factors, supporting the use of miRNAs within clinically used predictive models. Both findings warrant further validation studies.     

Phase I dose escalation trial of stereotactic radiotherapy prior to robotic prostatectomy in high risk prostate cancer

BackgroundThe aim of the study was to investigate the safety of combining preoperative stereotactic body radiotherapy (SBRT) with robotic radical prostatectomy (RP) for high risk prostate cancer (HRCaP). Many patients with HRCaP will require adjuvant or salvage radiotherapy after RP. The addition of preoperative SBRT before RP may spare patients from subsequent prolonged courses of RT.Materials and methodsEligible patients had NCC N HRCaP and received a total of 25 Gy or 30 Gy in five daily fractions of SBRT to the prostate and seminal vesicles followed by robotic RP with pelvic lymphadenectomy 31–45 days later. The primary endpoint was prevalence of acute genitourinary (GU) and gastrointestinal (GI) toxicity. Secondary endpoints were patient-reported quality of life (QOL) and biochemical recurrence (BcR).ResultsThree patients received preoperative SBRT to 25 Gy and four received 30 Gy. Median follow-up was 18 months. Highest toxicity was grade 2 and 3 in six (85.7%) and one (14.3%) patients, respectively. All patients developed grade 2 erectile dysfunction and 4 of 7 (57%) developed grade 2 urinary incontinence (UI) within a month after surgery. One patient developed acute grade 3 UI, but there was no grade ≥ 4 toxicity. One patient experienced acute grade 2 hemorrhoidal bleeding. On QOL, acute GU complaints were common and peaked within 3 months. Bowel symptoms were mild. Two patients with pN+ experienced BcR.ConclusionsPreoperative SBRT before robotic RP in HRCaP is feasible and safe. The severity of acute GU toxicity with preoperative SBRT may be worse than RP alone, while bowel toxicity was mild.     

Radiation therapy after radical prostatectomy: why patience is a virtue! The case for salvage radiation therapy

Without reliable clinical or pathologic predictors of local recurrence, selection of patients for adjuvant radiotherapy based on any combination of clinical or pathological parameters is bound to lead to the unnecessary treatment of significant numbers of patients whose disease might not have ultimately recurred or who might have been destined to have recurrence with extrapelvic metastatic disease, for which pelvic radiation would be ineffective. Furthermore, new ultrasensitive prostate-specific antigen (PSA) assays can identify patients actually failing surgery with a detectable and rising PSA earlier than ever, when disease volume is low and still amenable to salvage radiation therapy, and can allow the calculation of the PSA doubling time, which is gaining widespread acceptance as a proven predictor of response to salvage radiation therapy in this setting. Therefore, the rationale for preemptive adjuvant radiation therapy after radical prostatectomy is weaker than ever.     

Transitioning from conformal radiotherapy to intensity-modulated radiotherapy after radical prostatectomy: Clinical benefit,oncologic outcomes and incidence of gastrointestinal and urinary toxicities

AimThe purpose of this study was to review genitourinary (GU) and gastrointestinal (GI) toxicity associated with high-dose radiotherapy (RT) delivered with 3-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT) or volumetric arc therapy (VMAT) following radical prostatectomy (RP).BackgroundRP is a therapeutic option for the management of prostate cancer (PrCa). When assessing postoperative RT techniques for PrCa, the published literature focuses on patients treated with 2-dimensional conventional methods without reflecting the implementation of 3D-CRT, IMRT, or VMAT.Materials and methodsA total of 83 patients were included in this analysis; 30 patients received 3D-CRT, and 53 patients received IMRT/VMAT. Acute and late symptoms of the GU and lower GI tract were retrospectively graded according to the Radiation Therapy Oncology Group and the European Organization for Research and Treatment of Cancer radiation toxicity grading systems. The relapse failure-free rate and overall survival were also evaluated.ResultsThe rate of acute GU toxicity was 9.4% vs. 13.3% for the IMRT/VMAT and 3D-CRT groups (p = 0.583). The 5-year actuarial rates of late GI toxicity for IMRT/VMAT and 3D-CRT treatments were 1.9% and 6.7%, respectively. The rate of late GU toxicity for the IMRT/VMAT and 3D-CRT treatment groups was 7.5% and 16.6%, respectively (p = 0.199). We found no association between acute or late toxicity and the RT technique in univariate and multivariate analyses.ConclusionPostprostatectomy IMRT/VMAT and 3D-CRT achieved similar morbidity and cancer control outcomes. The clinical benefit of highly conformal techniques in this setting is unclear although formal analysis is needed.     

The effect of radiation therapy on post-prostatectomy urinary function

AimWe sought to evaluate the effect of radiation therapy on post-prostatectomy urinary quality of life in prostate cancer patients.BackgroundIn some men with non-metastatic prostate cancer, radiation therapy is indicated following prostatectomy. The radiation toxicity and quality of life considerations are unique in the post-prostatectomy setting.Materials and methodsA total of 106 patients receiving post-prostatectomy radiation therapy completed the Expanded Prostate Cancer Index Composite questionnaire before radiation and at 2-year follow-up. The primary outcomes of this study were the urinary domain summary score and subscale scores. Planned analysis was performed based on time interval from prostatectomy to radiation therapy.ResultsAmong the 106 patients analyzed, the mean urinary domain summary score worsened at 2-year follow-up after radiation therapy, lowering from 77.23–72.51 (p = 0.0085). Similar worsening was observed in the subscales of function (p = 0.003), bother (p = 0.0397), and incontinence (p = 0.0003). Urinary incontinence showed the greatest observable change among subscales. While the summary score worsened (p = 0.0031) among patients receiving radiation therapy more than 1 year after prostatectomy, it did not show statistically significant change in those treated 1 year or less after prostatectomy.ConclusionOur results demonstrate that post-prostatectomy radiation therapy is associated with modest declines in reportable urinary quality of life. Patients receiving radiation therapy more than 1 year after prostatectomy showed greater worsening of urinary quality of life, which indicates that there may be no functional advantage to delaying radiation therapy beyond the initial postoperative period.     

Salvage cryosurgery of the prostate after radiation failure

Radiation therapy is one option for patients with localized prostate cancer. Despite advances in delivering radiation to the prostate gland with therapies such as brachytherapy and/or external beam radiation therapy, urologists will be faced with managing patients with rising prostate-specific antigen values and with positive biopsy results secondary to radiation-recurrent prostate cancer. If the cancer is detected early, salvage therapy can be initiated. Since salvage prostatectomy is associated with significant morbidity, patients are often left with the option of either watchful waiting or temporary palliation with hormone deprivation therapy, with its attendant toxicity. The introduction of third-generation cryotechnology using 17-gauge CryoNeedlestrade mark (Oncura, Inc., Plymouth Meeting, PA) and the recent modifications in the technique of salvage cryosurgery have enabled cryosurgeons to eradicate these tumors safely and with significantly decreased morbidity. Selection and management of patients, as well as the contemporary results of salvage cryosurgery, are discussed in this article.     

Advances in the Management of Post-Radical Prostatectomy Erectile Dysfunction: Treatment Strategies When PDE-5 Inhibitors Don't Work

Phosphodiesterase type-5 (PDE-5) inhibitors have revolutionized the treatment of post-radical prostatectomy erectile dysfunction. For those patients who undergo a non-nerve-sparing radical prostatectomy or whose condition fails to respond to PDE-5 inhibitors, alternative treatment with intracavernous injection therapy, transurethral alprostadil, vacuum erection devices, and recently described combination therapy is available. The goals of therapy are to provide the patient with a means of obtaining an erection so that the patient and his partner may resume sexual relations as soon as possible following radical prostatectomy. There is evidence that early institution of treatment may promote improvement in the return of spontaneous erections in patients who have undergone nerve preservation. In patients who undergo non-nerve-sparing procedures, therapy may improve penile rigidity. Intracavernous injection therapy, transurethral alprostadil, and vacuum devices are highly effective in the management of post-prostatectomy erectile dysfunction. High dropout rates, which are not related to adverse effects, have been described with all 3 modalities. Pre- and postoperative counseling may improve patient and partner satisfaction.     

Salvage I-125 brachytherapy for locally-recurrent prostate cancer after radiotherapy

PurposeRetrospective, single-institution analysis of clinical outcomes and treatment-related toxicity in patients treated with salvage I-125 low-dose rate (LDR) brachytherapy (BT) for locally-recurrent prostate cancer after radiotherapy.Materials and methodsBetween 2008 and 2018, 30 patients with biopsy-confirmed prostate cancer recurrence underwent salvage treatment with I-125 LDR-BT. Of these 30 patients, 14 were previously treated with primary external beam radiotherapy (EBRT; median dose, 73 Gy) and 16 with primary I-125 LDR-BT (145 Gy and 160 Gy in 14 and 2 cases, respectively). At seed implantation, the mean age was 75.8 years, with a median Gleason score of 7 and pre-salvage PSA of <10 ng/mL. Six patients received androgen deprivation therapy for six months after relapse diagnosis. The prescribed salvage I-125 BT dose to the gland was 120−130 Gy, with dose restrictions of Dmax <135% (urethra) and <100% (rectum). Toxicity was evaluated according to the CTCAE scale (v4.0).ResultsAt a median follow-up of 45 months, the biochemical recurrence-free survival rates at 1, 3 and 5 years were 86.7%, 56.7% and 53.3%, respectively. Overall survival at 5 years was 87%. On the multivariate analysis, two variables were significant predictors of recurrence: PSA at relapse and nadir PSA post-salvage. Grade 3 genitourinary toxicity was observed in 5 patients (radiation-induced cystitis in 3 cases and urethral stenosis in 2) and G3 gastrointestinal toxicity in 3 patients (rectal bleeding).ConclusionSalvage therapy with I-125 brachytherapy is a safe and effective treatment option for locally-recurrent prostate cancer in previously-irradiated patients. High pre-salvage PSA and post-salvage nadir PSA values were significantly associated with a worse disease control after salvage I-125 LDR-BT. In well-selected patients, I-125 LDR-BT is comparable to other salvage therapies in terms of disease control and toxicity. However, more research is needed to determine the optimal management of locally-recurrent prostate cancer.     

Evaluation and treatment of men with biochemical prostate-specific antigen recurrence following definitive therapy for clinically localized prostate cancer

Early detection and monitoring by serum prostate-specific antigen (PSA) measurement has increased the number of men presenting with potentially curable prostate cancer. Most will choose radical prostatectomy or some form of radiation therapy for treatment, but some will have evidence of biochemical disease recurrence following therapy, shown by a rising PSA level without other clinical evidence of disease. Radical prostatectomy involves the removal of all prostate tissue, causing the serum PSA to decline to undetectable levels within four to six weeks following surgery; a subsequent rise in the serum PSA to a detectable level indicates disease recurrence. Patients should be evaluated to assess whether rising PSA levels indicate local recurrence or early metastatic disease. The advantages of salvage radiation, endocrine therapy, and other treatment modalities in local disease recurrence must be weighed against potential side effects and the resulting decrease in quality of life. Radiation therapy does not immediately eradicate all PSA-producing cells; therefore the persistence of a detectable PSA does not necessarily imply residual cancer, but rising PSA levels indicate treatment failure. Salvage surgery can be performed after radiotherapy for the purpose of removing all viable cancer cells, but should be weighed against a higher incidence of surgical complications; cryoablation offers a less invasive therapeutic modality.     

Management of clinically localized prostate cancer

Critics of screening have stated that early detection of prostate cancer does not necessarily reflect a diminishing death rate from the disease. However, several recent reports have demonstrated that the death rate from prostate cancer is decreasing, representing the most compelling validation for aggressive screening. Prostate cancer can be halted only if there is no evidence of systemic or regional metastases and the disease is confined to the surgical field or the radiation template. Surgeons and radiation oncologists must make a concerted effort to exclude men with regional and systemic metastases who are unlikely to benefit from treatment. With the widespread acceptance of prostate-specific antigen screening, a greater proportion of men are being diagnosed with clinically localized prostate cancer. Both radical prostatectomy and radiation therapy are able to halt disease spread in this significant subset of men, but survival outcomes indicate that radical prostatectomy is a more reliable treatment than radiation therapy for clinically localized prostate cancer. Overall, the immediate treatment-related morbidity of radical prostatectomy and radiation therapy in the modern era is quite low. Radical prostatectomy and radiation therapy appear to have a similar impact on continence and erectile function. There is a need for neoadjuvant and adjuvant therapies that can be utilized in those cases where radical prostatectomy and radiation are less likely to completely eradicate or destroy the cancer.     

Adjuvant gamma knife surgery and image-guided,intensity-modulated radiation therapy for the treatment of sacral chordomas

AimThe aim of this study was to confirm whether patients with sacral chordoma benefit from adjuvant radiotherapy and to determine the optimal photon radiotherapy module for comprehensive treatment.BackgroundChordoma is a rare slow-growing neoplasm arisen from cellular remnants of the notochord. About 50% occur in the sacrococcygeal region. Surgical resection and adjuvant radiation therapy are recommended treatment due to the improving local control rate.Materials and methods118 patients treated by surgery and adjuvant radiotherapy from August 2003 to May 2015 were retrospectively analyzed. All patients received surgical resection after diagnosis. Among these patients, 44 were treated by exclusive surgery, and 48 were treated with adjuvant image-guided, intensity-modulated radiation therapy (IG-IMRT). In addition, 26 patients were treated with gamma knife surgery (GKS) after surgical resection. The median follow-up was 54 months for all patients. Kaplan–Meier analysis was used to calculate recurrence-free survival (RFS) overall survival (OS).ResultsPatients treated with adjuvant radiotherapy had better RFS (p = 0.014) than those treated exclusively by surgery. The patients in the IG-IMRT group exhibited better recurrence-free survival (p = 0.01) than the GKS group. Moreover, in the IG-IMRT group, patients treated by higher dose were associated with better RFS (p = 0.04). No significant difference in OS was found. No grade 3 late toxicity was found.ConclusionsWe confirmed that adjuvant radiotherapy improved RFS but not OS in sacral chordoma patients after surgery. Furthermore, favorable RFS and low adverse event rates were observed following IG-IMRT. Our results suggest that high dose IG-IMRT is an appropriate module of adjuvant radiotherapy for sacral chordoma patients.     

Radiotherapy for cervical cancer: Chilean consensus of the Society of Radiation Oncology

BackgroundCervical cancer is a public health problem in Latin America. Radiotherapy plays a fundamental role both as definitive or adjuvant treatment. There are important intra and inter-country differences regarding access and availability of radiotherapy facilities in this region. The aim of a study was to standardize the basic clinical and technical criteria for the radiation treatment of patients with CC in Chile and provide a guide for Latin American Radiation Oncologists.Materials and methodsForty-one expert radiation oncologists from the Chilean Radiation Oncology Society made a consensus using the Delphi methodology.ResultsThere was a high degree of agreement for each of the recommendations. Those with the lowest percentage were related to the definition of the conformal 3D technique as the standard for definitive external radiotherapy (81%) and the criteria for extended nodal irradiation (85%).ConclusionsThese recommendations present an updated guide for radiotherapy treatment of patients with cervical cancer for Latin America. Those should be implemented according to local resources of each institution.     

Cavernous nerve reconstruction to preserve erectile function following non-nerve-sparing radical retropubic prostatectomy: a prospective study

Erectile dysfunction following radical prostatectomy for treatment of clinically localized prostate cancer remains a problem that deters many men from seeking surgical treatment. Sparing the cavernous nerves has been popularized as a method of preserving potency, but men with locally advanced disease may be at increased risk for positive margins with this technique. In this study, sural nerve grafting of the cavernous nerve bundles, to preserve postoperative potency while potentially maximizing cancer control, was examined. Thirty men were enrolled in this prospective phase I study and underwent non-nerve-sparing radical prostatectomy performed by one of two protocol surgeons. Preoperative erectile function was assessed both objectively, using a RigiScan (Timm Medical Technologies, Inc., Eden Prairie, Minn.), and subjectively. The cavernous nerves were identified and resected during the operation with the use of an intraoperative mapping device (CaverMap; Alliant Medical Technologies, Norwood, Mass.). Bilateral autologous sural nerve grafting to the cavernous nerve stumps was performed by one of two protocol plastic surgeons. Postoperative erectile dysfunction therapy, using intracorporeal injection, a vacuum pump, and/or oral sildenafil therapy, was instituted 6 weeks after the operation. Spontaneous erectile activity was subjectively and objectively measured every 3 months after the operation. Follow-up periods ranged from 13 to 33 months (mean, 23 months). Overall, 18 of 30 patients (60 percent) demonstrated both objective and subjective evidence of spontaneous erectile activity. Of those 18 men, 13 (72 percent) were able to have intercourse (seven unassisted and six with the aid of sildenafil). No disease or biochemical recurrences have been noted in this group of patients with locally advanced disease. In conclusion, autologous sural nerve grafting after non-nerve-sparing radical prostatectomy is an effective means of preserving spontaneous erectile activity after the operation while maximizing cancer control potential.     

Trends in Adjuvant External Beam Radiation Therapy for Nonanaplastic Thyroid Cancer in California, 2003-2017

BackgroundExternal beam radiation therapy (EBRT) is rarely used to treat patients with differentiated or medullary thyroid cancer. Although EBRT is generally administered to patients with high-risk or unresectable diseases, neither its indications for the use nor the associated outcomes are well-defined. We used a statewide cohort to assess the trends in EBRT use and postradiation outcomes in California.MethodsA population-based study of patients within the California Cancer Registry who underwent EBRT after surgery for nonanaplastic thyroid cancer (2003-2017) was conducted. The primary outcome was the annual utilization rate of EBRT. The secondary outcomes included Kaplan-Meier analysis for cause-specific survival and identifying factors associated with improved survival after EBRT.ResultsAmong the 57 607 patients with nonanaplastic thyroid cancer from 2003 to 2017, 344 (0.6%) patients received EBRT. EBRT was utilized in 0.4% of papillary, 1.1% of follicular, and 7.7% of medullary thyroid cancers in California. Overall, 99 (28.8%) patients treated with EBRT died of thyroid cancer. The 10-year cause-specific survival of all patients with thyroid cancer after EBRT was 61.5% (95% CI: 54.8%-69.1%) and that of patients without distant disease was 80.3% (95% CI: 73.5%-87.8%). The survival outcomes varied by tumor size, histology, disease stage, patient age at diagnosis, and the presence of extrathyroidal extension (P < .05).ConclusionsThe use of adjuvant EBRT for nonanaplastic thyroid cancer remained stable and low in California from 2003 to 2017. The comparative efficacy of EBRT was not discernible in this study, but disease control appeared durable in select patients. Well-controlled observational studies and/or prospective studies are needed to better define which patients benefit from EBRT.     

Safety of adjuvant intensity-modulated postoperative radiation therapy in endometrial cancer: Clinical data and dosimetric parameters according to the International Commission on Radiation Units (ICRU) 83 report

AimTo report a single-institution experience using postoperative pelvic Intensity Modulation Radiation Therapy (IMRT) using tomotherapy accelerators (TA) in postoperative endometrial cancer (EC) regarding ICRU 83 recommendations.BackgroundIMRT in gynecological malignancies provides excellent dosimetric data, lower rates of adverse events and clinical data similar to historical series.Material and methodsSeventy-six patients with EC were postoperatively treated with adjuvant IMRT using TA. The IMRT dose was 45 Gy for patients without positive lymph nodes and Type I histology and 50.4 Gy for patients with positive lymph nodes and/or type II histology.ResultsWith a median follow-up of 29 months, the 12- and 24-month Overall Survival (OS) and Disease-Free Survival (DFS) were 96%, 93%, 87%, and 74%, respectively. Age of less than 60 years was associated with better OS (HR: 8.9; CI: 1.1–68) and DFS (HR: 3.5; CI: 1.2–10.2). Patients with Type II and Type I Grade III histology had a worse OS (HR: 3.3; CI: 1.1–11). Five women (6.6%) presented in-field local vaginal recurrence, 2 (2.6%) presented non-in-field vaginal recurrence, 4 (5.2%) presented pelvic node and distant recurrence and 11 (14.4%) presented only distant metastases. One patient stopped radiation treatment due to Grade III acute diarrhea. No Grade III late toxicity was observed. Planning Target Volume (PTV) coverage showed mean D2, D50, D95, and D98 of 51.64–46.23 Gy, 49.49–44.97 Gy, 48.62–43.96 Gy, and 48.47–43.58 Gy for patients who received 45 and 50.4 Gy, respectively.ConclusionsIMRT with TA in postoperative EC shows excellent conformity and homogeneity of PTV dose. Without Grade III late toxicity, data from this cohort demonstrated the utility of IMRT.     

Association of single nucleotide polymorphisms in SOD2, XRCC1 and XRCC3 with susceptibility for the development of adverse effects resulting from radiotherapy for prostate cancer

The objective of this study was to determine whether an association exists between certain single nucleotide polymorphisms (SNPs), which have previously been linked with adverse normal tissue effects resulting from radiotherapy, and the development of radiation injury resulting from radiotherapy for prostate cancer. A total of 135 consecutive patients with clinically localized prostate cancer and a minimum of 1 year of follow-up who had been treated with radiation therapy, either brachytherapy alone or in combination with external-beam radiotherapy, with or without hormone therapy, were genotyped for SNPs in SOD2, XRCC1 and XRCC3. Three common late tissue toxicities were investigated: late rectal bleeding, urinary morbidity, and erectile dysfunction. Patients with the XRCC1 rs25489 G/A (Arg280His) genotype were more likely to develop erectile dysfunction after irradiation than patients who had the G/G genotype (67% compared to 24%; P=0.048). In addition, patients who had the SOD2 rs4880 T/C (Val16Ala) genotype exhibited a significant increase in grade 2 late rectal bleeding compared to patients who had either the C/C or T/T genotype for this SNP (8% compared to 0%; P=0.02). Finally, patients with the combination of the SOD2 rs4880 C/T genotype and XRCC3 rs861539 T/C (Thr241Met) genotype experienced a significant increase in grade 2 late rectal bleeding compared to patients without this particular genotypic arrangement (14% compared to 1%; P=0.002). These results suggest that SNPs in the SOD2, XRCC1 and XRCC3 genes are associated with the development of late radiation injury in patients treated with radiation therapy for prostate adenocarcinoma.     

The future of Radiation Oncology: Considerations of Young Medical Doctor

Radiation therapy plays an increasingly important role in the management of cancer. Currently, more than 50% of all cancer patients can expect to receive radiotherapy during the course of their disease, either in a primary management (radical or adjuvant radiotherapy) or for symptom control (palliative radiotherapy).Radiation oncology is a very unique branch of medicine connected with clinical knowledge and also with medical physics. In recent years, this approach has become increasingly absorbed with technological advances. This increasing emphasis on technology, together with other important changes in the health-care economic environment, now place the specialty of radiation oncology in a precarious position. New treatment technologies are evolving at a rate unprecedented in radiation therapy, paralleled by improvements in computer hardware and software. These techniques allow assessment of changes in the tumour volume and its location during the course of therapy (interfraction motion) so that re-planning can adjust for such changes in an adaptive radiotherapy process.If radiation oncologists become simply the guardians of a single therapeutic modality they may find that time marches by and, while the techniques will live on, the specialty may not. This article discusses these threats to the field and examines strategies by which we may evolve, diversify, and thrive.     

Penile prosthesis implantation for end-stage erectile dysfunction after radical prostatectomy

When erectile dysfunction occurs after radical prostatectomy and phosphodiesterase-5 inhibitor therapy fails, second-line therapies such as vacuum constriction devices, intraurethral prostaglandins, and penile injection therapy should be offered. When second-line therapies are not effective or acceptable to the man and his partner, penile prosthesis implantation becomes the treatment of choice. Today's 3-piece inflatable devices offer flaccidity and erection that approach the natural state. Design improvements have resulted in devices that have freedom from mechanical failure ranging from 92% to 94%. Antibiotic and hydrophilic coatings have reduced infection rates.     

Mortality Risk After Radioiodine Therapy for Hyperthyroidism: A Systematic Review and Meta-Analysis

ObjectiveRadioiodine has been increasingly used to treat hyperthyroidism for many years. Although widely regarded as an effective therapy, radioiodine treatment for hyperthyroidism has been suspected to be associated with the risk of mortality. This study aimed to quantify the mortality outcomes in patients who were treated for hyperthyroidism with radioiodine.MethodsSystematic search and meta-analysis were performed to determine the risk of mortality in patients treated with radioiodine for hyperthyroidism. Relevant studies were searched through August 2020 and selected in accordance with the inclusion criteria.ResultsA total of 13 studies were identified. The summary odds ratios (ORs) showed an increased risk of all-cause mortality in patients who were treated with radioiodine for hyperthyroidism (OR = 1.20; 95% CI = 1.07-1.35). The risk of death attributed to all forms of circulatory, respiratory, and endocrine and metabolic diseases was significantly increased, with summary ORs of 1.23 (95% CI, 1.12-1.35), 1.43 (95% CI, 1.17-1.75), and 2.38 (95% CI, 1.85-3.06), respectively. The summary ORs revealed no significant association between radioiodine treatment for hyperthyroidism and the risk of cancer mortality (OR = 1.03; 95% CI, 0.98-1.09). Radioiodine treatment for hyperthyroidism was not associated with the risk of mortality from breast, respiratory system, gastrointestinal, and genitourinary cancers.ConclusionRadioiodine treatment for hyperthyroidism is associated with the risk of all-cause mortality but not cancer mortality. Future research needs to address the causes of hyperthyroidism, effects of radioiodine therapy, and potential effects of confounding to identify causality.