Recent advances and impending challenges for the radiopharmaceutical sciences in oncology.

This paper is the first of a Series on theranostics that summarises the current landscape of the radiopharmaceutical sciences as they pertain to oncology. In this Series paper, we describe exciting developments in radiochemistry and the production of radionuclides, the development and translation of theranostics, and the application of artificial intelligence to our field. These developments are catalysing growth in the use of radiopharmaceuticals to the benefit of patients worldwide. We also highlight some of the key issues to be addressed in the coming years to realise the full potential of radiopharmaceuticals to treat cancer.

Guiding principles on the education and practice of theranostics.

PURPOSE: The recent development and approval of new diagnostic imaging and therapy approaches in the field of theranostics have revolutionised nuclear medicine practice. To ensure the provision of these new imaging and therapy approaches in a safe and high-quality manner, training of nuclear medicine physicians and qualified specialists is paramount. This is required for trainees who are learning theranostics practice, and for ensuring minimum standards for knowledge and competency in existing practising specialists. METHODS: To address the need for a training curriculum in theranostics that would be utilised at a global level, a Consultancy Meeting was held at the IAEA in May 2023, with participation by experts in radiopharmaceutical therapy and theranostics including representatives of major international organisations relevant to theranostics practice. RESULTS: Through extensive discussions and review of existing curriculum and guidelines, a harmonised training program for theranostics was developed, which aims to ensure safe and high quality theranostics practice in all countries. CONCLUSION: The guiding principles for theranostics training outlined in this paper have immediate relevance for the safe and effective practice of theranostics.

Prevalence of human papillomavirus in head and neck cancers at tertiary care centers in the United States over time.

BACKGROUND: Human papillomavirus (HPV) is responsible for a growing proportion of oropharyngeal squamous cell carcinomas (OPSCCs) among men and White individuals. Whether similar trends apply to women, non-Whites, and non-oropharyngeal squamous cell carcinomas (non-OPSCCs) is unknown. METHODS: This is a cross-sectional analysis combining 2 multi-institutional case series of incident head and neck squamous cell carcinoma (HNSCC) cases. Incident HNSCCs from 1995 to 2012 were enrolled retrospectively using banked tumor samples and medical record abstraction. Incident HNSCCs from 2013 to 2019 were enrolled prospectively. The prevalence of tumor HPV biomarkers was tested over 3 time periods (1995-2003, 2004-2012, and 2013-2019). Centralized testing was done for p16 immunohistochemistry (p16) and oncogenic HPV in situ hybridization (ISH). RESULTS: A total of 1209 incident cases of HNSCC were included. Prevalence of p16- and ISH-positive tumors increased significantly for oropharynx cancers over time. The majority were positive after 2013 for White patients (p16, 92%; P < .001; ISH 94%; P < .001), Black patients (p16, 72%; P = .021; ISH 67%; P = .011), and Hispanic patients (p16, 100%; P = .04; ISH 100%; P = .013). For women with OPSCC, the prevalence of p16- and ISH-positive tumors increased significantly to 82% (P < .001) and 78% (P = .004), respectively. For non-OPSCCs, there was increased p16 and ISH positivity overall with 24% p16 and 16% ISH positivity in the most recent time period (P < .001 for both). CONCLUSIONS: The majority of OPSCCs in US tertiary care centers are now p16 and ISH positive for all sex and race groups. In some populations in the United States, 91% of OPSCCs are now caused by HPV. Few non-OPSCCs are p16 and ISH positive.

A phase II randomized trial of RAdium-223 dichloride and SABR Versus SABR for oligomEtastatic prostate caNcerS (RAVENS).

BACKGROUND: Metastasis directed therapy (MDT) for patients with oligometastatic disease is associated with improvements in progression free survival (PFS) and overall survival (OS) compared to systemic therapy alone. Additionally, within a prostate-cancer-specific cohort, MDT is able to forestall initiation of androgen deprivation therapy (ADT) in men with hormone-sensitive, oligometastatic prostate cancer (HSOPCa) compared to observation. While MDT appears to be safe and effective in HSOPCa, a large percentage of men will eventually have disease recurrence. Patterns of failure in HSOPCa demonstrate patients tend to have recurrence in the bone following MDT, raising the question of sub-clinically-apparent osseous disease. Radium-223 dichloride is a radiopharmaceutical with structural similarity to calcium, allowing it to be taken up by bone where it emits alpha particles, and therefore might have utility in the treatment of micrometastatic osseous disease. Therefore, the primary goal of the phase II RAVENS trial is to evaluate the efficacy of MDT + radium-223 dichloride in prolonging progression free survival in men with HSOPCa. METHODS: Patients with HSOPCa and 3 or less metastases with at least 1 bone metastasis will be randomized 1:1 to stereotactic ablative radiation (SABR, also known as stereotactic body radiation therapy (SBRT)) alone vs SABR + radium-223 dichloride with a minimization algorithm to balance assignment by institution, primary intervention, prior hormonal therapy, and PSA doubling time. SABR is delivered in one to five fractions and patients in the SABR + radium-223 dichloride arm will receive six infusions of radium-223 dichloride at four-week intervals. The primary end point is progression free survival. The secondary clinical endpoints include toxicity and quality of life assessments, local control at 12 months, locoregional progression, time to distant progression, time to new metastasis, and duration of response. DISCUSSION: The RAVENS trial will be the first described phase II, non-blinded, randomized study to compare SABR +/- radium-223 dichloride in patients with HSOPCa and 3 or less metastases with at least one bone metastasis. The primary hypothesis is that SABR + radium-223 dichloride will increase median progression-free survival from 10 months in the SABR arm to 20 months in the SABR + radium-223 dichloride arm. TRIAL REGISTRATIONS: Clinicaltrials.gov. Identifier: NCT04037358. Date of Registration: July 30, 2019. Date of First Participant Enrolled: August 9, 2019. Date of Last Approved Amendment: October 16, 2019. Protocol Version: Version 5.

Priorities, concerns, and regret among patients with head and neck cancer.

BACKGROUND: In the era of deintensification, little data are available regarding patients' treatment preferences. The current study evaluated treatment-related priorities, concerns, and regret among patients with head and neck squamous cell cancer (HNSCC). METHODS: A total of 150 patients with HNSCC ranked the importance of 10 nononcologic treatment goals relative to the oncologic goals of cure and survival. The level of concern regarding 11 issues and decision regret was recorded. Median rank was reported overall, and factors associated with odds of rank as a top 3 priority were modeled using logistic regression. RESULTS: Among the treatment effects analyzed, the odds of being a top 3 priority was especially high for cure (odds, 9.17; 95% confidence interval [95% CI], 5.05-16.63), followed by survival and swallow (odds, 1.26 [95% CI, 0.88-1.80] and odds, 0.85 [95% CI, 0.59-1.21], respectively). Prioritization of cure, survival, and swallow was similar based on human papillomavirus (HPV) tumor status. By increasing decade of age, older participants were found to be significantly less likely than younger individuals to prioritize survival (odds ratio, 0.72; 95% CI, 0.52-1.00). Concerns regarding mortality (P = .04) and transmission of HPV to the patient's spouse (P = .03) were more frequent among participants with HPV-associated HNSCC. Regret increased with additional treatment modalities (P = .02). CONCLUSIONS: Patients with HNSCC overwhelming prioritize cure, followed by survival and swallow. The decreased prioritization of survival by older age supports further examination of treatment preference by age. The precedence of oncologic over nononcologic priorities among patients regardless of HPV tumor status supports the conservative adoption of deintensification regimens until the interplay between competing oncologic and nononcologic treatment goals is better understood.

Surgical salvage improves overall survival for patients with HPV-positive and HPV-negative recurrent locoregional and distant metastatic oropharyngeal cancer.

BACKGROUND: Human papillomavirus (HPV) tumor status and surgical salvage are associated with improved prognosis for patients with recurrent oropharyngeal squamous cell carcinoma (OPSCC). Current data regarding types of surgery and the impact of surgery for patients with distant metastatic disease are limited. METHODS: A retrospective analysis of patients with recurrent OPSCC from 2 institutions between 2000 and 2012 was performed. p16 immunohistochemistry and/or in situ hybridization, as clinically available, were used to determine HPV tumor status. Clinical characteristics, distribution of recurrence site, and treatment modalities were compared by HPV tumor status. Overall survival (OS) was examined using Kaplan-Meier and Cox proportional hazards methods. RESULTS: The current study included 108 patients with 65 locoregional and 43 distant metastatic first recurrences. The majority of patients were HPV-positive (80 patients). HPV-positive tumor status was associated with longer time to disease recurrence (P<.01). Anatomic site distribution of disease recurrences did not differ by HPV tumor status. HPV-positive tumor status (adjusted HR [aHR], 0.23; 95% confidence interval [95% CI], 0.09-0.58 [P = .002]), longer time to disease recurrence (≥ 1 year; aHR, 0.36; 95% CI, 0.18-0.74 [P = .006]), and surgical salvage (aHR, 0.26; 95% CI, 0.12-0.61 [P = .002]) were found to be independently associated with OS after disease recurrence. Surgical salvage was independently associated with improved OS compared with nonsurgical treatment among patients with both locoregional (aHR, 0.15; 95% CI, 0.04-0.56 [P = .005]) and distant (aHR, 0.19; 95% CI, 0.05-0.75 [P = .018]) metastatic disease recurrences. CONCLUSIONS: Surgical salvage was found to be associated with improved OS for patients with recurrent locoregional and distant metastatic OPSCC, independent of HPV tumor status. Further prospective data are needed to confirm the role of surgical salvage for distant metastases.

FDG PET/CT for Management and Assessing Outcomes of Squamous Cell Cancer of the Oral Cavity.

OBJECTIVE: FDG PET/CT has excellent diagnostic accuracy for detecting locoregional nodal and distant metastases, can be used to assess therapeutic response, and provides valuable information about prognosis in patients with oral cavity cancer. The aim of this article is to summarize the value of FDG PET/CT in the treatment of patients with squamous cell cancer of the oral cavity. CONCLUSION: FDG PET/CT is a valuable imaging study in the management of oral squamous cell cancer and in predicting patient outcome.

Diagnostic Accuracy of Follow-Up FDG PET or PET/CT in Patients With Head and Neck Cancer After Definitive Treatment: A Systematic Review and Meta-Analysis.

OBJECTIVE: The purpose of this study was to assess the diagnostic performance of FDG PET or PET/CT for detection of local, regional, and distant recurrences in the follow-up of patients with head and neck cancer who underwent definitive treatment. MATERIALS AND METHODS: A systematic search was performed in MEDLINE and Cochrane Library (updated September 2014) to identify relevant published studies. Studies investigating the accuracy of FDG PET/CT that were performed at least 4 months after therapy were included. Two authors independently screened all retrieved articles, selected studies that met the inclusion criteria, and extracted the data. Histopathologic confirmation or clinical follow-up of at least 6 month (or both) was considered as the reference standard. RESULTS: Twenty-three studies constituting a total of 2247 FDG PET/CT examinations met our inclusion criteria. The pooled sensitivity and specificity of follow-up PET/CT for detection of recurrence were 0.92 (95% CI, 0.90-0.94), and 0.87 (95% CI, 0.82-0.91), respectively. The pooled sensitivity and specificity of scans performed 4-12 months after treatment were 0.95 (95% CI, 0.91-0.97) and 0.78 (95% CI, 0.70-0.84), respectively. Similar estimates for scans performed at or more than 12 months after treatment were 0.92 (95% CI, 0.85-0.96) and 0.91 (95% CI, 0.78-0.96), respectively. The overall accuracy of FDG PET/CT in detecting recurrence is higher in patients without suspicion of recurrence before the scan compared with the patients with suspected recurrence. CONCLUSION: The high diagnostic performance of FDG PET/CT in detecting recurrence in curatively treated patients with head and neck cancer supports its use in clinical practice for patient follow-up. Further studies are needed to evaluate the prognostic utility of PET/CT in the follow-up of head and neck cancer.

Radiotheranostics in advanced prostate cancer: Current and future directions.

The discovery of small molecules that target the extracellular domain of prostate-specific membrane antigen (PSMA) has led to advancements in diagnostic imaging and the development of precision radiopharmaceutical therapies. In this review, we present the available existing data and highlight the key ongoing clinical evaluations of PSMA-based imaging in the management of primary, biochemically recurrent, and metastatic prostate cancer. We also discuss clinical studies that explore the use of PSMA-based radiopharmaceutical therapy (RPT) in metastatic prostate cancer and forthcoming trials that investigate PSMA RPT in earlier disease states. Multidisciplinary collaboration in clinical trial design and therapeutic administration is critical to the continued progress of this evolving radiotheranostics field.

Factors Impacting Provider Treatment Decision-Making in Early Glottic Cancer.

OBJECTIVES: Transoral laser microsurgery (TLMS) and radiotherapy (XRT) are mainstays of treatment for early glottic carcinoma (EGC). Here, we investigated case-dependent provider treatment preferences and identify factors which impact decision-making in EGC. METHODS: This cross-sectional survey of laryngologists, head-and-neck surgeons, and radiation oncologists presented five diagrammatic cases of progressively advanced EGC (T1/2, N0). Respondents indicated preference for TLMS or XRT and ranked factors which influenced their recommendation for each case. Analysis utilized descriptive statistics, Fischer's exact tests, and Kruskal-Wallis tests for nonparametric data. RESULTS: A total of 141 complete responses (69.5% laryngologists) were received. Most respondents practiced in academic settings (93.5%) and within multidisciplinary teams (94.0%). Anterior commissure involvement was the most important a priori tumor factor for case-independent treatment recommendation (Likert Scale: 4.22/5), followed by Laterality (Likert Scale: 4.02/5). Across all specialties, TLMS was recommended for unilateral T1a lesions. Laryngologists continued recommending TLMS in T2 lesions (41.0%) more than head-and-neck surgeons (5.0%) and radiation oncologists (0.0%). Across all cases, survival and voice outcomes were the most important clinical factors impacting treatment decisions. Radiation oncologists weighed voice more heavily than laryngologists in more complex presentations of EGC (rank: 1.6 vs. 2.7, Kruskall-Wallis: p < 0.05). CONCLUSIONS: In more complex clinical presentations of EGC, preference for TLMS compared to XRT differed across specialists, despite similar rankings of factors driving these treatment recommendations. This may be driven by differing experiences and viewpoints on case-dependent voice outcomes following TLMS versus XRT, suggesting a need for increased understanding of how tumor location and depth impact voice outcomes. LEVEL OF EVIDENCE: 5 Laryngoscope, 134:3686-3694, 2024.

The Potential Contribution of Radiopharmaceutical Therapies in Managing Oligometastatic Disease.

There is a growing understanding of the oligometastatic disease state, characterized by the presence of 5 or fewer lesions. Advanced molecular imaging techniques, such as prostate-specific membrane antigen PET, refines the ability to detect oligometastatic recurrences (oligorecurrences) early. These developments have led to the exploration of metastasis-directed therapy (MDT) in oligorecurrent disease as an alternative to or as a means of delaying systemic therapy. Unfortunately, MDT often does not provide a durable cure, and progression-particularly progression in multiple new areas-remains a concern. Simultaneously, developments in radioligand therapy (RLT) have led to studies showing overall survival benefits with α-emitting and ß-emitting RLT in advanced, high-volume, metastatic castration-resistant prostate cancer. The success of RLT in late-stage disease suggests that earlier use in the disease spectrum may be impactful. Specifically, integration of RLT with MDT might reduce progression, including polymetastatic progression, in the setting of oligorecurrent disease.

Machine learning predicts conventional imaging metastasis-free survival (MFS) for oligometastatic castration-sensitive prostate cancer (omCSPC) using prostate-specific membrane antigen (PSMA) PET radiomics.

PURPOSE: This study investigated imaging biomarkers derived from PSMA-PET acquired pre- and post-metastasis-directed therapy (MDT) to predict 2-year metastasis-free survival (MFS), which provides valuable early response assessment to improve patient outcomes. MATERIALS/METHODS: An international cohort of 117 oligometastatic castration-sensitive prostate cancer (omCSPC) patients, comprising 34 from John Hopkins Hospital (JHH) and 83 from Baskent University (BU), were treated with stereotactic ablative radiation therapy (SABR) MDT with both pre- and post-MDT PSMA-PET/CT scans acquired. PET radiomic features were analyzed from a CT-PET fusion defined gross tumor volume ((GTV) or zone 1), and a 5 mm expansion ring area outside the GTV (zone 2). A total of 1748 PET radiomic features were extracted from these zones. The six most significant features selected using the Chi2 method, along with five clinical parameters (age, Gleason score, number of total lesions, untreated lesions, and pre-MDT prostate-specific antigen (PSA)) were extracted as inputs to the models. Various machine learning models, including Random Forest, Decision Tree, Support Vector Machine, and Naïve Bayesian, were employed for 2-year MFS prediction and tested using leave-one-out and cross-institution validation. RESULTS: Six radiomic features, including Total Energy, Entropy, and Standard Deviation from pre-PSMA-PET zone 1, Total Energy and Contrast from post-PSMA-PET zone 1, and Entropy from pre-PSMA-PET zone 2, along with five clinical parameters were selected for predicting 2-year MFS. In a leave-one-out test with all the patients, random forest achieved an accuracy of 80 % and an AUC of 0.82 in predicting 2-year MFS. In cross-institution validation, the model correctly predicted 2-year MFS events with an accuracy of 75 % and an AUC of 0.77 for patients from JHH, and an accuracy of 78 % and an AUC of 0.80 for BU patients, respectively. CONCLUSION: Our study demonstrated the promise of using pre- and post-MDT PSMA-PET-based imaging biomarkers for MFS prediction for omCSPC patients.

Multi-institutional Analysis of Metastasis-directed Therapy with or Without Androgen Deprivation Therapy in Oligometastatic Castration-sensitive Prostate Cancer.

BACKGROUND: Metastasis-directed therapy (MDT) is increasingly being used in oligometastatic castration-sensitive prostate cancer (omCSPC). However, it is currently unclear how to optimally integrate MDT with the standard of care of systemic hormonal therapy. OBJECTIVE: To report long-term outcomes of MDT alone versus MDT and a defined course of androgen deprivation therapy (ADT) in omCSPC. DESIGN, SETTING, AND PARTICIPANTS: Here, a multicenter, international retrospective cohort of omCSPC as defined by conventional imaging was reported. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Biochemical progression-free survival (bPFS), distant progression-free survival (dPFS), and combined biochemical or distant progression-free survival (cPFS) were evaluated with Kaplan-Meier and multivariable Cox proportional hazard regression models. RESULTS AND LIMITATIONS: A total of 263 patients were included, 105 with MDT + ADT and 158 with MDT alone. The majority of patients had metachronous disease (90.5%). Five-year bPFS, dPFS, and cPFS were, respectively, 24%, 41%, and 19% in patients treated with MDT + ADT and 11% (hazard ratio [HR] 0.48, 95% confidence interval [CI] 0.36-0.64), 29% (HR 0.56, 95% CI 0.40-0.78), and 9% (HR 0.50, 95% CI 0.38-0.67) in patients treated with MDT alone. On a multivariable analysis adjusting for pretreatment variables, the use of ADT was associated with improved bPFS (HR 0.43, p < 0.001), dPFS (HR 0.45, p = 0.002), and cPFS (HR 0.44, p < 0.001). CONCLUSIONS: In this large multi-institutional report, the addition of concurrent ADT to MDT appears to improve time to prostate-specific antigen progression and distant recurrence, noting that about 10% patients had durable control with MDT alone. Ongoing phase 3 studies will help further define treatment options for omCSPC. PATIENT SUMMARY: Here, we report a large retrospective review evaluating the outcomes of metastasis-directed therapy with or without a limited course of androgen deprivation for patients with oligometastatic castration-sensitive prostate cancer. This international multi-institutional review demonstrates that the addition of androgen deprivation therapy to metastasis-directed therapy (MDT) improves progression-free survival. While a proportion of patients appear to have long-term disease control with MDT alone, further work in biomarker discovery is required to better identify which patients would be appropriate for de-escalated therapy.

Prostate-Specific Membrane Antigen PET Response Associates with Metastasis-Free Survival After Stereotactic Ablative Radiation in Oligometastatic Prostate Cancer.

Purpose: Emerging data suggest that metastasis-directed therapy (MDT) improves outcomes in patients with oligometastatic castration-sensitive prostate cancer (omCSPC). Prostate-specific membrane antigen positron emission tomography (PSMA-PET) can detect occult metastatic disease, and PSMA response has been proposed as a biomarker for treatment response. Herein, we identify and validate a PSMA-PET biomarker for metastasis-free survival (MFS) following MDT in omCSPC. Methods and Materials: We performed an international multi-institutional retrospective study of patients with omCSPC, defined as ≤3 lesions, treated with metastasis-directed stereotactic ablative radiation who underwent PSMA-PET/computed tomography (CT) before and after (median, 6.2 months; range, 2.4-10.9 months) treatment. Pre- and post-MDT PSMA-PET/CT maximum standardized uptake value (SUVmax) was measured for all lesions, and PSMA response was defined as the percent change in SUVmax of the least responsive lesion. PSMA response was both evaluated as a continuous variable and dichotomized into PSMA responders, with a complete/partial response (at least a 30% reduction in SUVmax), and PSMA nonresponders, with stable/progressive disease (less than a 30% reduction in SUVmax). PSMA response was correlated with conventional imaging-defined metastasis-free survival (MFS) via Kaplan-Meier and Cox regression analysis. Results: A total of 131 patients with 261 treated metastases were included in the analysis, with a median follow-up of 29 months (IQR, 18.5-41.3 months). After stereotactic ablative radiation, 70.2% of patients were classified as PSMA responders. Multivariable analysis demonstrated that PSMA response as a continuous variable was associated with a significantly worse MFS (hazard ratio = 1.003; 95% CI, 1.001-1.006; P = .016). Patients classified as PSMA responders were found to have a significantly improved median MFS of 39.9 versus 12 months (P = .001) compared with PSMA nonresponders. Our study is limited as it is a retrospective review of a heterogenous population. Conclusions: After stereotactic ablative radiation, PSMA-PET response appears to be a radiographic biomarker that correlates with MFS in omCSPC. This approach holds promise for guiding clinical management of omCSPC and should be validated in a prospective setting.

Genomic Determinants Associated with Modes of Progression and Patterns of Failure in Metachronous Oligometastatic Castration-sensitive Prostate Cancer.

BACKGROUND AND OBJECTIVE: Oligometastatic castration-sensitive prostate cancer (omCSPC) represents an early state in the progression of metastatic disease for which patients experience better outcomes in comparison to those with higher disease burden. Despite the generally more indolent nature, there is still much heterogeneity, with some patients experiencing a more aggressive clinical course unexplained by clinical features alone. Our aim was to investigate correlation of tumor genomics with the mode of progression (MOP) and pattern of failure (POF) following first treatment (metastasis-directed and/or systemic therapy) for omCSPC. METHODS: We performed an international multi-institutional retrospective study of men treated for metachronous omCSPC who underwent tumor next-generation sequencing with at least 1 yr of follow-up after their first treatment. Descriptive MOP and POF results are reported with respect to the presence of genomic alterations in pathways of interest. MOP was defined as class I, long-term control (LTC; no radiographic progression at last follow-up), class II, oligoprogression (1-3 lesions), or class III, polyprogression (≥4 lesions). POF included the location of lesions at first failure. Genomic pathways of interest included TP53, ATM, RB1, BRCA1/2, SPOP, and WNT (APC, CTNNB1, RNF43). Genomic associations with MOP/POF were compared using χ2 tests. Exploratory analyses revealed that the COSMIC mutational signature and differential gene expression were also correlated with MOP/POF. Overall survival (OS) was calculated via the Kaplan-Meier method from the time of first failure. KEY FINDINGS AND CLINICAL IMPLICATIONS: We included 267 patients in our analysis; the majority had either one (47%) or two (30%) metastatic lesions at oligometastasis. The 3-yr OS rate was significantly associated with MOP (71% for polyprogression vs 91% for oligoprogression; p = 0.005). TP53 mutation was associated with a significantly lower LTC rate (27.6% vs 42.3%; p = 0.04) and RB1 mutation was associated with a high rate of polyprogression (50% vs 19.9%; p = 0.022). Regarding POF, bone failure was significantly more common with tumors harboring TP53 mutations (44.8% vs25.9%; p = 0.005) and less common with SPOP mutations (7.1% vs 31.4%; p = 0.007). Visceral failure was more common with tumors harboring either WNT pathway mutations (17.2% vs 6.8%, p = 0.05) or SPOP mutations (17.9% vs 6.3%; p = 0.04). Finally, visceral and bone failures were associated with distinct gene-expression profiles. CONCLUSIONS AND CLINICAL IMPLICATIONS: Tumor genomics provides novel insight into MOP and POF following treatment for metachronous omCSPC. Patients with TP53 and RB1 mutations have a higher likelihood of progression, and TP53, SPOP, and WNT pathway mutations may have a role in metastatic organotropism. PATIENT SUMMARY: We evaluated cancer progression after a first treatment for metastatic prostate cancer with up to five metastases. We found that mutations in certain genes were associated with the location and extent of further metastasis in these patients.

Patterns of relapse in stage I-II uterine papillary serous carcinoma treated with adjuvant intravaginal radiation (IVRT) with or without chemotherapy.

OBJECTIVE: To evaluate patterns of relapse in early stage uterine papillary carcinoma (UPSC) patients receiving adjuvant intravaginal radiotherapy (IVRT) with or without chemotherapy. METHODS: From 1/1996 to 12/2010, 77 women with stage I-II UPSC underwent surgery followed by IVRT (median 21Gy). Stage IA patients without residual disease at surgery were excluded. IVRT and chemotherapy (carboplatin/taxane) was given to 61 (79%) patients and IVRT alone to 16 (21%). The median follow-up was 62 months for surviving patients. RESULTS: Of the 77 patients, 11 (14%) relapsed as follows: vaginal 2 (3%), pelvic 5 (6%), para-aortic 5 (6%), peritoneal 6 (8%), and other distant sites 8 (10%). Of the 5 pelvic relapses, 2 were isolated and were salvaged. In those treated without chemotherapy, only 1/16 developed recurrence (mediastinal). The 5-year vaginal, pelvic, para-aortic, peritoneal, and distant recurrence rates were 2.7% (C.I. 0-6.2%), 5.8% (C.I. 0.6-11.0%), 5.4% (C.I. 0.6-10.1%), 5.3% (C.I. 0.5-10.1%) and 6.6% (C.I. 1.4-11.8%), respectively. The 5-year disease-free survival (DFS), and overall survival (OS) were 88% (C.I. 81-95%), and 91% (C.I. 84-97%), respectively. The only predictor of worse 5-year pelvic control was stage (96.2% stage IA vs 87.7% for stage IB-II, p=0.043). CONCLUSIONS: In stage I-II UPSC patients who predominantly receive adjuvant chemotherapy, IVRT as the sole form of adjuvant RT provides excellent locoregional control. The risk of isolated pelvic recurrence is too low to warrant routine use of external pelvic RT.

PSMA-targeted therapy for non-prostate cancers.

Radioligand therapy (RLT) agents are demonstrating a crucial role in the clinical approach to aggressive malignancies such as metastatic castrate-resistant prostate cancer (m-CRPC). With the recent FDA approval of prostate-specific membrane antigen (PSMA)-targeted RLT for m-CRPC, the field has broadened its gaze to explore other cancers that express PSMA in the tumor parenchyma or tumor neovasculature. In this review article, we discuss current progress in the clinical use of PSMA RLTs in non-prostate cancers such salivary gland cancers, renal cell carcinoma, high grade glioma, and soft tissue sarcoma. We highlight early reports in small case series and clinical trials indicating promise for PSMA-targeted RLT and highlighting the importance of identifying patient cohorts who may most benefit from these interventions. Further study is indicated in non-prostate cancers investigating PSMA RLT dosimetry, PSMA PET/CT imaging as a biomarker, and assessing PSMA RLT safety and efficacy in these cancers.

Clinical and Genomic Differences Between Advanced Molecular Imaging-detected and Conventional Imaging-detected Metachronous Oligometastatic Castration-sensitive Prostate Cancer.

In metastatic castration-sensitive prostate cancer (mCSPC), disease volume plays an integral role in guiding treatment recommendations, including selection of docetaxel therapy, metastasis-directed therapy, and radiation to the prostate. Although there are multiple definitions of disease volume, they have commonly been studied in the context of metastases detected via conventional imaging (CIM). One such numeric definition of disease volume, termed oligometastasis, is heavily dependent on the sensitivity of the imaging modality. We performed an international multi-institutional retrospective review of men with metachronous oligometastatic CSPC (omCSPC), detected via either advanced molecular imaging alone (AMIM) or CIM. Patients were compared with respect to clinical and genomic features using the Mann-Whitney U test, Pearson's χ2 test, and Kaplan-Meier overall survival (OS) analyses with a log-rank test. A total of 295 patients were included for analysis. Patients with CIM-omCSPC had significantly higher Gleason grade group (p = 0.032), higher prostate-specific antigen at omCSPC diagnosis (8.0 vs 1.7 ng/ml; p < 0.001), more frequent pathogenic TP53 mutations (28% vs 17%; p = 0.030), and worse 10-yr OS (85% vs 100%; p < 0.001). This is the first report of clinical and biological differences between AMIM-detected and CIM-detected omCSPC. Our findings are particularly important for ongoing and planned clinical trials in omCSPC. PATIENT SUMMARY: Metastatic prostate cancer with just a few metastases only detected via newer scanning methods (called molecular imaging) is associated with fewer high-risk DNA mutations and better survival in comparison to metastatic cancer detected via conventional scan methods.

A Multimedia Strategy to Integrate Introductory Broad-Based Radiation Science Education in US Medical Schools.

US physicians in multiple specialties who order or conduct radiological procedures lack formal radiation science education and thus sometimes order procedures of limited benefit or fail to order what is necessary. To this end, a multidisciplinary expert group proposed an introductory broad-based radiation science educational program for US medical schools. Suggested preclinical elements of the curriculum include foundational education on ionizing and nonionizing radiation (eg, definitions, dose metrics, and risk measures) and short- and long-term radiation-related health effects as well as introduction to radiology, radiation therapy, and radiation protection concepts. Recommended clinical elements of the curriculum would impart knowledge and practical experience in radiology, fluoroscopically guided procedures, nuclear medicine, radiation oncology, and identification of patient subgroups requiring special considerations when selecting specific ionizing or nonionizing diagnostic or therapeutic radiation procedures. Critical components of the clinical program would also include educational material and direct experience with patient-centered communication on benefits of, risks of, and shared decision making about ionizing and nonionizing radiation procedures and on health effects and safety requirements for environmental and occupational exposure to ionizing and nonionizing radiation. Overarching is the introduction to evidence-based guidelines for procedures that maximize clinical benefit while limiting unnecessary risk. The content would be further developed, directed, and integrated within the curriculum by local faculties and would address multiple standard elements of the Liaison Committee on Medical Education and Core Entrustable Professional Activities for Entering Residency of the Association of American Medical Colleges.

Adjuvant trastuzumab reduces locoregional recurrence in women who receive breast-conservation therapy for lymph node-negative, human epidermal growth factor receptor 2-positive breast cancer.

BACKGROUND: Patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancer have a higher risk of locoregional recurrence (LRR), even in the setting of early stage, lymph node-negative disease. In this sequential, retrospective study, the authors evaluated whether adjuvant trastuzumab was associated with reduced LRR in women with lymph node-negative, HER2-positive disease who received breast-conservation therapy (BCT). METHODS: By using an institutional database, 197 women were identified who had lymph node-negative, HER2-positive breast cancer measuring ≤5 cm diagnosed between 2002 and 2008 and who received BCT, including whole-breast irradiation. Two cohorts were compared: 70 women who did not receive trastuzumab (the no-trastuzumab cohort) and 102 women who did receive trastuzumab (the trastuzumab cohort). Kaplan-Meier methods were used to estimate LRR-free survival. RESULTS: The 2 cohorts were similar in age, tumor size, histology, and hormone receptor status. Chemotherapy was received by 73% of the no-trastuzumab cohort and by 100% of the trastuzumab cohort. In both groups, 99% of patients completed radiotherapy with a median dose of 60 Gray. The median recurrence-free follow-up was 86 months for the no-trastuzumab cohort and 47 months for the trastuzumab cohort. The 3-year LRR-free survival rate was 90% (95% confidence interval, 83%-97%) for the no-trastuzumab cohort and 99% (95% confidence interval, 97%-100%) for the trastuzumab cohort. In the no-trastuzumab cohort, LRR occurred in 7 patients (median time to LRR, 14 months). In the trastuzumab cohort, there was 1 LRR at 14 months. CONCLUSIONS: Even among women with lower risk breast cancer, the relatively high locoregional failure rates associated with positive HER2 status could be reduced markedly with adjuvant trastuzumab chemotherapy. Within 3 years, a 10% LRR rate without trastuzumab and a 1% LRR rate with trastuzumab were observed in women with lymph node-negative disease who received BCT.