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Purpose: To explore the prostate-specific membrane antigen (PSMA)-avid distribution of prostate cancer (PC) on positron emission tomography (PET), both at the time of initial diagnosis and at the time of relapse after definitive local treatment., Methods and Materials: A total of 179 PSMA PET scans in patients with nil or ≤3 lesions on conventional imaging were retrospectively categorized into 3 subgroups: group A, high-risk PC with no prior definitive therapy (n=34); group B, prior prostatectomy (n=75); and group C, prior radiation therapy (n=70). The numbers and locations of the PSMA-avid lesions were mapped. The PSMA-positive lesions were identified subjectively by a nuclear medicine physician on the basis of clinical experience and taking into account the recent literature and artefacts., Results: A total of 893 PSMA-avid lesions were identified; at least 1 lesion was detected in 80% of all scans. A high detection rate was present even at very low serum PSA levels (eg, at PSA ≤0.20 ng/mL in group B, the detection rate was 46%). Thirty-eight percent of studies revealed extrapelvic disease (41%, 31%, and 46% in groups A, B, and C, respectively). Almost one-third of all studies showed only oligometastases (24%, 36%, and 31% in groups A, B, and C, respectively). A large proportion of these (40%) were a solitary lesion., Conclusions: Prostate-specific membrane antigen PET demonstrated a large number of otherwise unknown metastatic lesions. Therefore we recommend PSMA PET for more accurate assessment of disease burden in initial staging of high-risk PC, as well as for restaging in patients with prostate-specific antigen relapse after primary therapies. Furthermore, a high proportion of oligometastases on PSMA PET provides a prime opportunity to investigate the role of targeted local therapies for oligometastatic PCs., (Crown Copyright © 2017. Published by Elsevier Inc. All rights reserved.)

Purpose: Decision regret (DR) is a negative emotion associated with medical treatment decisions, and it is an important patient-centered outcome after therapy for localized prostate cancer. DR has been found to occur in up to 53% of patients treated for localized prostate cancer, and it may vary depending on treatment modality. DR after modern dose-escalated radiation therapy (DE-RT) has not been investigated previously, to our knowledge. Our primary aim was to evaluate DR in a cohort of patients treated with DE-RT., Methods and Materials: We surveyed 257 consecutive patients with localized prostate cancer who had previously received DE-RT, by means of a validated questionnaire., Results: There were 220 responses (85.6% response rate). Image-guided intensity modulated radiation therapy was given in 85.0% of patients and 3-dimensional conformal radiation therapy in 15.0%. Doses received included 73.8 Gy (34.5% patients), 74 Gy (53.6%), and 76 Gy (10.9%). Neoadjuvant androgen deprivation (AD) was given in 51.8% of patients and both neoadjuvant and adjuvant AD in 34.5%. The median follow-up time was 23 months (range, 12-67 months). In all, 3.8% of patients expressed DR for their choice of treatment. When asked whether they would choose DE-RT or AD again, only 0.5% probably or definitely would not choose DE-RT again, compared with 8.4% for AD (P<.01)., Conclusion: Few patients treated with modern DE-RT express DR, with regret appearing to be lower than in previously published reports of patients treated with radical prostatectomy or older radiation therapy techniques. Patients experienced more regret with the AD component of treatment than with the radiation therapy component, with implications for informed consent. Further research should investigate regret associated with individual components of modern therapy, including AD, radiation therapy and surgery., (Crown Copyright © 2013. Published by Elsevier Inc. All rights reserved.)

Purpose: To review the outcome of palliative radiotherapy (RT) alone in patients with symptomatic locally advanced or recurrent gastric cancer., Methods and Materials: Patients with symptomatic locally advanced or recurrent gastric cancer who were managed palliatively with RT at The Cancer Institute, Singapore were retrospectively reviewed. Study end points included symptom response, median survival, and treatment toxicity (retrospectively scored using the Common Toxicity Criteria v3.0 [CTC])., Results: Between November 1999 and December 2004, 33 patients with locally advanced or recurrent gastric cancer were managed with palliative intent using RT alone. Median age was 76 years (range, 38-90 years). Twenty-one (64%) patients had known distant metastatic disease at time of treatment. Key index symptoms were bleeding (24 patients), obstruction (8 patients), and pain (8 patients). The majority of patients received 30 Gy/10 fractions (17 patients). Dose fractionation regimen ranged from an 8-Gy single fraction to 40 Gy in 16 fractions. Median survival was 145 days, actuarial 12-month survival 8%. A total of 54.3% of patients (13/24) with bleeding responded (median duration of response of 140 days), 25% of patients (2/8) with obstruction responded (median duration of response of 102 days), and 25% of patients (2/8) with pain responded (median duration of response of 105 days). No obvious dose-response was evident. One Grade 3 CTC equivalent toxicity was recorded., Conclusion: External beam RT alone is an effective and well tolerated modality in the local palliation of gastric cancer, with palliation lasting the majority of patients' lives.

Purpose: There has been little radiation oncologist (RO)-specific research in continuing medical education (CME) or quality improvement (QI) program efficacy. Our aim was to evaluate a CME/QI program for changes in RO behavior, performance, and adherence to department protocols/studies over the first 12 months of the program., Methods and Materials: The CME/QI program combined chart audit with feedback (C-AWF), simulation review AWF (SR-AWF), reminder checklists, and targeted CME tutorials. Between April 2003 and March 2004, management of 75 patients was evaluated by chart audit with feedback (C-AWF) and 178 patients via simulation review audit (SR-AWF) using a validated instrument. Scores were presented, and case management was discussed with individualized educational feedback. RO behavior and performance was compared over the first year of the program., Results: Comparing the first and second 6 months, there was a significant improvement in mean behavior (12.7-13.6 of 14, p = 0.0005) and RO performance (7.6-7.9 of 8, p = 0.018) scores. Protocol/study adherence significantly improved from 90.3% to 96.6% (p = 0.005). A total of 50 actions were generated, including the identification of learning needs to direct CME tutorials, the systematic change of suboptimal RO practice, and the alteration of deficient management of 3% of patients audited during the program., Conclusion: An integrated CME/QI program combining C-AWF, SR-AWF, QI reminders, and targeted CME tutorials effectively improved targeted RO behavior and performance over a 12-month period. There was a corresponding increase in departmental protocol and study adherence.

Purpose: The external audit of oncologist clinical practice is increasingly important because of the incorporation of audits into national maintenance of certification (MOC) programs. However, there are few reports of external audits of oncology practice or decision making. Our institution (The Cancer Institute, Singapore) was asked to externally audit an oncology department in a developing Asian nation, providing a unique opportunity to explore the feasibility of such a process., Methods and Materials: We audited 100 randomly selected patients simulated for radiotherapy in 2003, using a previously reported audit instrument assessing clinical documentation/quality assurance and medical decision making., Results: Clinical documentation/quality assurance, decision making, and overall performance criteria were adequate 74.4%, 88.3%, and 80.2% of the time, respectively. Overall 52.0% of cases received suboptimal management. Multivariate analysis revealed palliative intent was associated with improved documentation/clinical quality assurance (p = 0.07), decision making (p = 0.007), overall performance (p = 0.003), and optimal treatment rates (p = 0.07); non-small-cell lung cancer or central nervous system primary sites were associated with better decision making (p = 0.001), overall performance (p = 0.03), and optimal treatment rates (p = 0.002)., Conclusions: Despite the poor results, the external audit had several benefits. It identified learning needs for future targeting, and the auditor provided facilitating feedback to address systematic errors identified. Our experience was also helpful in refining our national revalidation audit instrument. The feasibility of the external audit supports the consideration of including audit in national MOC programs.

Purpose: With the results of the INT0116 study, adjuvant radiochemotherapy has become the standard treatment after complete resection of gastric adenocarcinoma. However, the implementation of radiotherapy (RT) remains a concern. In response, consensus guidelines on RT technique have been published. Our objective was to measure the inter- and intraclinician variability in RT field delineation using conventional two- (2D) and three-dimensional (3D) techniques., Methods and Materials: Between 1999 and 2003, five radiation oncologists (ROs) treated 45 patients with completely resected, gastric adenocarcinoma using postoperative radiochemotherapy (INT0116). Two cases were included in this study (Patient 1 had cardia and Patient 2 had antral disease). Standardized vignettes (with surgical and pathologic findings) and preoperative and postoperative imaging for each case were developed. Each RO designed AP-PA fields for each patient (2D planning) on two separate occasions. This was repeated using a 3D planning technique., Results: Patient 1 had a mean field area of 250.2 cm(2) (SD 12.0) and 227.9 cm(2) (SD 26.5) using 2D and 3D planning, respectively (p = 0.03). The mean clinical target volume (CTV) volume was 468.3 cm(3) (SD 65.9). Patient 1 had a significantly greater inter- than intra-RO variation for the field area designed with 3D planning; however, no difference occurred with 2D planning or CTV contouring. Patient 2 had a mean field area of 234.8 cm(2) (SD 33.1) and 226.8 cm(2) (SD 19.3) using 2D and 3D planning, respectively (p = 0.5). The mean CTV was 729.4 cm(3) (SD 67.3). For Patient 2, the inter-RO variability was significantly greater than the intra-RO variability for the field area using both 2D and 3D planning, and no difference was seen for the CTV. Composite beam's-eye-view plots revealed that the superior, inferior, and right lateral borders proved to be most contentious., Conclusion: Despite published guidelines and a departmental protocol, significant variations in the RT field areas were seen among ROs for both 2D and 3D planning. However, in general, CTV contouring was reproducible. Because 3D-RT hinges on accurate target identification, caution should be exercised before migrating to 3D planning for postoperative gastric cancer.

Purpose: Our primary aim was to design a new, internationally accredited, comprehensive radiation oncology (RO) training program for Singaporean residents that satisfied the needs of stake holders and incorporated published evidence., Methods and Materials: The evidence-based method included Medline literature review and broad-based training needs assessment., Results: Literature review revealed few studies describing or evaluating RO resident training programs. Our program was designed by incorporating available published research and stakeholder views determined by the training needs assessment. The program includes novel evidence-based educational methods, including individually negotiated learning contracts, a mentor program, logbooks, task-based learning, tutorials, and formative plus summative assessments. The content and structure is consistent with most United States, United Kingdom, and Royal Australian and New Zealand College of Radiologist (RANZCR) guidelines, with resident evaluation via RANZCR examinations. The RANZCR accredited the program in January 2002., Conclusion: We recommend institutions or countries introducing or revising RO resident training programs use an evidence-based approach, addressing the needs of stake holders (determined by a comprehensive training needs assessment) and incorporating published research. Novel educational methods may be considered in RO training. This new Singapore program is the first to achieve international accreditation by the RANZCR. It is clear that additional research in the design and evaluation of RO resident training programs is required.

Purpose: The 2000 practice guidelines of the National Comprehensive Cancer Network recommend World Health Organization Type 2-3 nasopharyngeal carcinoma (NPC) be staged for distant disease using chest X-ray and bone scan. Our aim was to evaluate these modalities plus liver ultrasonography for American Joint Committee on Cancer/International Union Against Cancer 1997 clinical Stage I-IVB NPC., Methods and Materials: Between February 1999 and May 2002, all patients with clinical (examination plus CT/MRI of head and neck) Stage I-IVB undifferentiated NPC were prospectively evaluated for distant disease with chest X-ray, liver ultrasonography, and bone scan. Suspicious lesions underwent confirmatory investigation, and patients were reevaluated at 4 months., Results: In the 139 patients evaluated, the positive yield was 3.6% and prevalence was 5.8% (0.7% lung, 2.2% skeletal, and 2.9% liver metastases). The prevalence increased by N stage (p = 0.004) and overall stage (p = 0.05). Compared with N3 disease (odds ratio 1.0), the odds of metastases for N0, N1, and N2 disease was 0, 0.12, and 0.33, respectively. The positive yield was 0%, 1.8%, 4.8%, and 14.3% for N0, N1, N2, and N3 disease, respectively., Conclusion: This is the first study to evaluate the use of distant staging investigations for American Joint Committee on Cancer/International Union Against Cancer 1997 staged NPC. We recommend alterations to the 2000 National Comprehensive Cancer Network guidelines as follows: high-risk (N3) disease should be fully staged with chest X-ray, bone scan, and liver ultrasonography; intermediate risk (N1 and N2) disease may be staged using all three modalities on an institutional basis. No evidence supports distant imaging for low-risk (N0 or Stage I) disease.

Purpose: Estimating the risks of radiotherapy (RT) toxicity is important for informed consent; however, the consistency in estimates has not been studied. This study aimed to explore the variability and factors affecting risk estimates (REs)., Methods and Materials: A survey was mailed to Australian radiation oncologists, who were asked to estimate risks of RT complications given 49 clinical scenarios. The REs were assessed for association with oncologist experience, subspecialization, and private practice., Results: The REs were extremely variable, with a 50-fold median variability. The least variability (sevenfold) was for estimates of late, small intestinal perforation/obstruction after a one-third volume received 50 Gy with concurrent 5-fluorouracil (RE range 5-35%). The variation between the smallest and largest REs in 17 scenarios was >or=100-fold. The years of experience was significantly associated with REs of soft/connective-tissue toxicity (p = 0.01) but inversely associated with estimates of neurologic/central nervous system toxicity (p = 0.08). Ninety-six percent of respondents believed REs were important to RT practice; only 24% rated evidence to support their estimates as good. Sixty-seven percent believed national/international groups should pursue the issue further., Conclusion: Enormous variability exists in REs for normal tissue complications due to RT that is influenced by the years of experience. Risk estimation is perceived as an important issue without a good evidence base. Additional studies are strongly recommended.