Enrichment of "Cribriform" morphologies (intraductal and cribriform adenocarcinoma) and genomic alterations in radiorecurrent prostate cancer.

Locally relapsed prostate cancer (PCa) after radiation therapy (RT) is associated with substantial morbidity and mortality. Morphological and molecular consequences that may contribute to RT resistance and local recurrence remain poorly understood. Locally recurrent PCa tissue from 53 patients with clinically localized PCa who failed with primary RT and subsequently underwent salvage radical prostatectomy (RP) was analyzed for tumor focality, clinicopathological, molecular, and genomic characteristics. Targeted next-generation sequencing with full exon coverage of 1,425 cancer-related genes was performed on 10 representative radiorecurrent PCas exhibiting no RT effect with matched adjacent benign prostate tissue. At RP, 37 (70%) of PCas had no RT effect with the following characteristics: grade group (GG) ≥ 3 (70%), unifocal tumor (75%), extraprostatic disease (78%), lymph node metastasis (8%), and "cribriform" morphologies (84%) [cribriform PCa (78%) or intraductal carcinoma (IDC-P) (61%)] at a median percentage of approximately 80% of tumor volume. In the setting of multifocal tumors (25%) at RP, the cribriform morphologies were restricted to index tumors. Of 32 patients with available pre-RT biopsy information, 16 had GG1 PCa, none had cribriform morphologies at baseline but 81% demonstrated cribriform morphologies at RP. Notable alterations detected in the sequenced tumors included: defects in DNA damage response and repair (DDR) genes (70%) (TP53, BRCA2, PALB2, ATR, POLQ), PTEN loss (50%), loss of 8p (80%), and gain of MYC (70%). The median tumor mutational burden was 4.18 mutations/Mb with a range of 2.16 to 31.86. Our findings suggest that most radiorecurrent PCas are enriched in cribriform morphologies with potentially targetable genomic alterations. Understanding this phenotypic and genotypic diversity of radiorecurrent PCa is critically important to facilitate optimal patient management.

A phase II randomized placebo-controlled double-blind study of salvage radiation therapy plus placebo versus SRT plus enzalutamide with high-risk PSA-recurrent prostate cancer after radical prostatectomy (SALV-ENZA).

BACKGROUND: In men with a rising PSA following radical prostatectomy, salvage radiation therapy (SRT) offers a second chance for cure. Hormonal therapy can be combined with SRT in order to increase prostate tumor control, albeit with associated higher rates of treatment side effects. This trial studies the effectiveness of SRT combined with hormonal therapy using a more potent anti-androgen with a favorable side effect profile. Enzalutamide, a next generation selective androgen receptor antagonist, is approved by the Food and Drug Administration for the treatment of metastatic castrate-resistant prostate cancer (CRPC) where it has been shown to improve overall survival in combination with androgen deprivation therapy. The primary objective of this study is to evaluate the efficacy of combination SRT and enzalutamide for freedom-from-PSA-progression. Secondary objectives include time to local recurrence within the radiation field, metastasis-free survival and safety as determined by frequency and severity of adverse events. METHODS/DESIGN: This is a randomized, double-blind, phase II, prospective, multicenter study in adult males with biochemically recurrent prostate cancer following radical prostatectomy. Following registration, enzalutamide 160 mg or placebo by mouth (PO) once daily will be administered for 6 months. Following two months of study drug, external beam radiotherapy to 66.6-70.2 Gray (Gy) will be administered to the prostate bed over 7-8 weeks while continuing daily placebo/enzalutamide. This is followed by two additional months of placebo/enzalutamide. DISCUSSION: The SALV-ENZA trial is the first phase II placebo-controlled double-blinded randomized study to test SRT in combination with a next generation androgen receptor antagonist in men with high-risk recurrent prostate cancer after radical prostatectomy. The primary hypothesis of this study is that clinical outcomes will be improved by the addition of enzalutamide compared to standard-of-care SRT alone and pave the path for phase III evaluation of this combination. TRIAL REGISTRATIONS: ClinicaltTrials.gov Identifier: NCT02203695 Date of Registration: 06/16/2014. Date of First Participant Enrollment: 04/16/2015.

Erectile function after stereotactic body radiotherapy for localized prostate cancer.

OBJECTIVE: To elucidate the functional erection rate after prostate stereotactic body radiotherapy (SBRT) and to develop a comprehensive prognostic model of outcomes after treatment. PATIENTS AND METHODS: Between 2008 and 2013, 373 consecutive men with localized prostate cancer were treated with SBRT at a single academic institution as part of a prospective clinical trial or prospective registry. Prospective longitudinal patient-reported health-related quality of life (HRQoL) data was collected using the Expanded Prostate Cancer Index Composite (EPIC)-26 instrument. Functional erections were strictly defined as 'firm enough for intercourse' according to EPIC-26. Detailed comorbidity data were also collected. Logistic regression models were used to predict 24- and 60-month functional erection rates. Observed erection rates after SBRT were compared with those after other radiation therapies (external beam radiation therapy [EBRT] and brachytherapy) using prospectively validated models. RESULTS: The median (interquartile range) follow-up was 56 (37-73) months and the response rate at 2 years was 84%. For those with functional erections at baseline, 57% and 45% retained function at 24 and 60 months, respectively. On multivariable analysis for 24-month erectile function, significant variables included higher baseline sexual HRQoL (adjusted odds ratio [aOR] 1.55 per 10 points, 95% confidence interval [CI] 1.37-1.74; P < 0.001) and older age (aOR 0.66 per 10 years, 95% CI 0.43-1.00; P = 0.05). At 60 months, baseline HRQoL and age remained associated with erectile function, along with body mass index (aOR 0.45, 95% CI 0.26-0.78; P < 0.001). The 24- and 60-month models had excellent discrimination (c-index 0.81 and 0.84, respectively). Erection rates after SBRT were not statistically different from model-predicted rates after EBRT or brachytherapy for the whole cohort and the cohort with baseline erectile function. CONCLUSIONS: Intermediate- to long-term post-SBRT erectile function results are promising and not significantly different from other radiotherapy techniques. Clinicians can use our prognostic model to counsel patients regarding expected erectile function after SBRT.

Natural history of 'second' biochemical failure after salvage radiation therapy for prostate cancer: a multi-institution study.

OBJECTIVES: To describe the natural history of prostate cancer in men who experience a second biochemical recurrence (BCR) after salvage radiotherapy (SRT) after prostatectomy. PATIENTS AND METHODS: After undergoing SRT at one of two institutions between 1986 and 2013, 286 patients experienced a second BCR, defined as two rises in prostate-specific antigen (PSA) of ≥0.2 ng/mL above nadir. Event rates for distant metastasis (DM) or freedom from DM (FFDM), castration-resistant prostate cancer (CRPC), prostate cancer-specific survival (PCSS), and overall survival (OS) were estimated using the Kaplan-Meier method. Cox regression was used for comparative analyses. RESULTS: At a median of 6.1 years after second BCR, DM, CRPC, PCSS and OS rates were 41%, 27%, 83% and 73%, respectively. On multivariable analysis, interval to second BCR <1 year (hazard ratio [HR] 2.66, 95% confidence interval [CI] 1.71-4.14; P < 0.001], Gleason score 8-10 (HR 1.65, 95% CI 1.07-2.54; P = 0.022), and concurrent ADT during SRT (HR 1.76, 95% CI 1.08-2.88; P = 0.024) were associated with FFDM, while PCSS was associated with interval to second BCR <1 year (HR 3.00, 95% CI 1.69-5.32; P < 0.001) and concurrent ADT during SRT (HR 2.15, CI 1.13-4.08; P = 0.019). These risk factors were used to stratify patients into three groups, with 6-year FFDM rates of 71%, 59% and 33%, and PCSS rates of 89%, 79%, and 65%, respectively. CONCLUSION: Following second BCR after SRT, clinical progression is enriched in a subgroup of patients with prostate cancer, while others remain without DM for long intervals. Stratifying patients into risk groups using prognostic factors may aid counselling and future trial design.

Rectal radiation dose-reduction techniques in prostate cancer: a focus on the rectal spacer.

Prostate cancer is the most common cancer in men. External beam radiotherapy by a variety of methods is a standard treatment option with excellent disease control. However, acute and late rectal side effects remain a limiting concern in intensification of therapy in higher-risk patients and in efforts to reduce treatment burden in others. A number of techniques have emerged that allow for high-radiation dose delivery to the prostate with reduced risk of rectal toxicity, including image-guided intensity-modulated radiation therapy, endorectal balloons and various forms of rectal spacers. Image-guided radiation therapy, either intensity-modulated radiation therapy or stereotactic ablative radiation therapy, in conjunction with a rectal spacer, is an efficacious means to reduce acute and long-term rectal toxicity.

Anatomical patterns of recurrence following biochemical relapse after post-prostatectomy salvage radiation therapy: a multi-institutional study.

OBJECTIVES: To characterise the frequency and detailed anatomical sites of failure for patients receiving post-radical prostatectomy (RP) salvage radiation therapy (SRT). PATIENTS AND METHODS: A multi-institutional retrospective study was performed on 574 men who underwent SRT between 1986 and 2013. Anatomical recurrence patterns were classified as lymphotrophic (lymph nodes only), osteotrophic (bone only), or multifocal if both were present. Isolated first failure sites were defined as sites of initial clinically detected recurrence that remained isolated for at least 3 months. RESULTS: The median follow-up after SRT was 6.8 years. The 8-year rates of local, regional, and distant failure for patients undergoing SRT were 2%, 6%, and 21%, respectively. Of the 22% men (128 of 574) who developed a clinically detectable recurrence, 17%, 50%, and 31% were lymphotrophic, osteotrophic, and multifocal, respectively. The trophic nature of metastases was prognostic for distant metastases-free survival (DMFS) and prostate cancer-specific survival (PCSS); the 10-year rates of DMFS were 18%, 5%, and 7% (P < 0.01), and PCSS were 78%, 68%, and 56% (P < 0.01), for lymphotrophic, osteotrophic, and multifocal failure patterns, respectively. CONCLUSIONS: We demonstrate that trophism for metastatic site has significant prognostic impact on PCSS in men treated with SRT. Radiographic local failure is an uncommon event after SRT when compared to historical data of patients treated with surgery monotherapy. However, distant failure remains a challenge in this patient population and warrants further therapeutic investigation.

Genomic characterization of response to chemoradiation in urothelial bladder cancer.

BACKGROUND: The authors characterized the genetic landscape of chemoradiation-treated urothelial carcinoma of the bladder (UCB) with the objective of identifying potential correlates of response. METHODS: Primary tumors with (n = 8) or without (n = 40) matched recurrent tumors from 48 patients who had non-metastatic, high-grade UCB and received treatment primarily with chemoradiation were analyzed using a next-generation sequencing assay enriched for cancer-related and canonical DNA damage response (DDR) genes. Protein expression of meiotic recombination 11 homolog (MRE11), a previously suggested biomarker, was assessed in 44 patients. Recurrent tumors were compared with primary tumors, and the clinical impact of likely deleterious DDR gene alterations was evaluated. RESULTS: The profile of alterations approximated that of prior UCB cohorts. Within 5 pairs of matched primary-recurrent tumors, a median of 92% of somatic mutations were shared. A median 33% of mutations were shared between 3 matched bladder-metastasis pairs. Of 26 patients (54%) who had DDR gene alterations, 12 (25%) harbored likely deleterious alterations. In multivariable analysis, these patients displayed a trend toward reduced bladder recurrence (hazard ratio, 0.32; P = .070) or any recurrence (hazard ratio, 0.37; P = .070). The most common of these alterations, ERCC2 (excision repair cross-complementation group 2) mutations, were associated with significantly lower 2-year metastatic recurrence (0% vs 43%; log-rank P = .044). No impact of MRE11 protein expression on outcome was detected. CONCLUSIONS: A similar mutation profile between primary and recurrent tumors suggests that pre-existing, resistant clonal populations represent the primary mechanism of chemoradiation treatment failure. Deleterious DDR genetic alterations, particularly recurrent alterations in ERCC2, may be associated with improved chemoradiation outcomes in patients with UCB. A small sample size necessitates independent validation of these observations. Cancer 2016;122:3715-23. © 2016 American Cancer Society.

Genomic Biomarkers for the Prediction of Stage and Prognosis of Upper Tract Urothelial Carcinoma.

PURPOSE: Genomic characterization of radical nephroureterectomy specimens in patients with upper tract urothelial carcinoma may allow for thoughtful integration of systemic and targeted therapies. We sought to determine whether genomic alterations in upper tract urothelial carcinoma are associated with adverse pathological and clinical outcomes. MATERIALS AND METHODS: Next generation exon capture sequencing of 300 cancer associated genes was performed in 83 patients with upper tract urothelial carcinoma. Genomic alterations were assessed individually and also grouped into core signal transduction pathways or canonical cell functions for association with clinicopathological outcomes. Binary outcomes, including grade (high vs low), T stage (pTa/T1/T2 vs pT3/T4) and organ confined status (pT2 or less and N0/Nx vs greater than pT2 or N+) were assessed with the Kruskal-Wallis and Fisher exact tests as appropriate. Associations between alterations and survival were estimated using the Kaplan-Meier method and Cox regression. RESULTS: Of the 24 most commonly altered genes in 9 pathways TP53/MDM2 alterations and FGFR3 mutations were the only 2 alterations uniformly associated with high grade, advanced stage, nonorgan confined disease, and recurrence-free and cancer specific survival. TP53/MDM2 alterations were associated with adverse clinicopathological outcomes whereas FGFR3 mutations were associated with favorable outcomes. We created a risk score using TP53/MDM2 and FGFR3 status that was able to discriminate between adverse pathological and clinical outcomes, including in the subset of patients with high grade disease. The study is limited by small numbers and lack of validation. CONCLUSIONS: Our data indicate that specific genomic alterations in radical nephroureterectomy specimens correlate with tumor grade, stage and cancer specific survival outcomes.

Comparison of outcomes in early stage uterine carcinosarcoma and uterine serous carcinoma.

OBJECTIVE: To assess whether contemporary adjuvant management of early stage uterine carcinosarcoma (CS) produces equal outcomes as in uterine serous carcinoma (USC). METHODS: We reviewed 172 women treated from 2000 to 2011 for stage I-II USC (n=112, 65%) or CS (n=60, 35%). Adjuvant therapy was initiated in 154 (90%) patients, with 111 patients receiving intravaginal radiotherapy (IVRT)/chemotherapy. Median follow up was 4.6 years for surviving patients. RESULTS: Characteristics for USC vs. CS did not differ significantly by age ≥60, pelvic or para-aortic node sampling, stage, lymphovascular invasion, chemotherapy use, RT use or omission of adjuvant therapy. Outcomes were better for USC vs. CS in 5-year actuarial rates of recurrence [17% (C.I. 10-25%) vs. 45% (C.I. 31-59%), p<0.001],disease-related mortality (DRM) [11% (5-17%) vs. 30% (16-44%), p=0.016], and all-cause mortality [12% (C.I. 6-18%) vs. 34% (C.I. 20-48%), p=0.007]. In multivariable analysis, CS histology remained a significant predictor of risk for recurrence [HR 3.1 (C.I. 1.7-5.7), p<0.001], DRM [HR 2.4 (C.I. 1.1-5.1), p=0.024], and all-cause mortality [HR 2.4 (C.I. 1.2-4.8), p=0.012]. On sub-group analysis of 111 patients (77 USC, 34 CS) able to receive IVRT/chemotherapy, CS no longer was associated significantly with increased recurrence (29% vs. 15%, p=0.18), DRM (22% vs. 10%, p=0.39), or all-cause mortality (22% vs. 10%, p=0.45). CONCLUSIONS: CS was associated with worse outcomes than USC. However, that difference was not maintained in patients able to receive IVRT and chemotherapy. While intriguing, this result may be due in part to selection against rapid early relapsing CS patients in this group.

Radioactive Iodine Therapy in Differentiated Thyroid Cancer: An Update on Dose Recommendations and Risk of Secondary Primary Malignancies.

Radioactive iodine (RAI) therapy with iodine-131 is performed in select cases of differentiated thyroid cancer (DTC), typically for remnant ablation, adjuvant therapy, or treatment of known persistent disease. Herein, we review updated RAI dose recommendations and associated risks of secondary primary malignancy (SPM). RAI dose is usually chosen empirically based on the risk assessment of tumor recurrence and other factors. Dose recommendations differ slightly among relevant medical societies. As of April 2024, most medical societies, including the American Thyroid Association (ATA), European Thyroid Association (ETA), Society of Nuclear Medicine and Molecular Imaging/European Association of Nuclear Medicine (SNMMI/ EANM), and National Comprehensive Cancer Network (NCCN), recommend a dose of 1.11 GBq (30 mCi) I-131 for remnant ablation. For adjuvant therapy, the recommended RAI dose ranges from 1.11 to 3.7 GBq (30-100) mCi I-131, although doses up to 5.6 GBq (150 mCi) may also be considered. In patients with known or suspected metastatic disease, at least 3.7 GBq (100 mCi) I-131 should be administered, and RAI doses as high as 7.4 GBq (200 mCi) may be justified depending on the suspected tumor burden and extent. Dosimetry has the advantage of tailoring the RAI dose to each patient's pharmacokinetics, resulting in ≥ 7.4 GBq (200 mCi) of I-131 in most cases. There is an ongoing debate about the risk of developing SPM due to RAI therapy, with several multicenter studies and meta-analyses concerning SPM being published in the last 2 years. The incidence of RAI-associated SPM varies according to the study design and detection method. Several studies showed no increased incidence, and there was no specific secondary cancer or cancer group linked to RAI exposures. Some reports indicated that cumulative RAI doses exceeding 5.6-7.4 GBq (150-200 mCi) were found to represent an increased risk for developing SPM. However, a clearly defined dose threshold cannot be provided based on the current literature. Nonetheless, caution should be exercised when considering repeated RAI therapies for persistent metastatic PTC, with a cumulative dose exceeding 37.0 GBq (1,000 mCi), due to the potential risk of developing SPM and other long-term toxicity. Further research is warranted to understand better the relationship between RAI dose and the risk of SPM.

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.

Optimizing Palliative Focal Radiation Therapy Dose in Cutaneous T-Cell Lymphoma: How Low Can You Go?

PURPOSE: Primary cutaneous T-cell lymphomas (CTCLs) are radiosensitive tumors with variable and often relapsing courses. Local disease can be treated with low-dose focal palliative radiation therapy (RT), though little data supports the use of a specific dose. This study assesses clinical outcomes after focal RT to a total dose of 4 Gy, 8 Gy, or 12 Gy. METHODS AND MATERIALS: An International Review Board-approved, retrospective, single-institution study was performed of 225 lesions in 41 patients with primary CTCL treated with low-dose focal RT from 2015 to 2020. Patient, tumor, and treatment characteristics were reviewed. The primary outcome was freedom from treatment failure (FFTF), defined as time to requiring local retreatment, and secondary outcomes included response rates and toxicities. RESULTS: Of the 225 lesions, 90 received 4 Gy, 106 received 8 Gy, and 29 received 12 Gy. Lesions treated with 12 Gy (96%) or 8 Gy (92%) had a significantly higher 1-year FFTF compared with 4 Gy (77%) (P = .034). Overall response rate and complete response rate were not significantly different between different doses (P = .117), though there was a trend toward higher overall response rate at initial assessment with 8 Gy versus 4 Gy (91.5% vs 82.2%, P = .057). Toxicity was low, with 7.1% of lesions having grade 2 or higher radiation dermatitis. CONCLUSIONS: In primary CTCL lesions treated with focal palliative RT, a dose response was noted favoring 8 to 12 Gy, with 1-year FFTF rates over 90%. However, 4 Gy resulted in substantially better outcomes than previously reported, with 77% requiring no further treatment at 1 year and comparable response rates to higher doses. While our data substantiates 8 to 12 Gy as the standard of care, it also suggests that 4 Gy should be considered an acceptable alternative in situations with concern for radiation toxicities, such as with fragile or heavily pretreated skin.

Quality Metric to Assess Adequacy of Hydrogel Rectal Spacer Placement for Prostate Radiation Therapy and Association of Metric Score With Rectal Toxicity Outcomes.

Purpose: Although hydrogel spacer placement (HSP) minimizes rectal dose during prostate cancer radiation therapy, its potential benefit for modulating rectal toxicity could depend on the achieved prostate-rectal separation. We therefore developed a quality metric associated with rectal dose reduction and late rectal toxicity among patients treated with prostate stereotactic body radiation therapy (SBRT). Methods and Materials: A quality metric consisting of prostate-rectal interspace measurements from axial T2-weighted magnetic resonance imaging simulation images was applied to 42 men enrolled in a multi-institutional phase 2 study using HSP with prostate SBRT (45 Gy in 5 fractions). A score of 0, 1, or 2 was assigned to a prostate-rectal interspace measurement of <0.3 cm, 0.3 to 0.9 cm, or ≥1 cm, respectively. An overall spacer quality score (SQS) was computed from individual scores at rectal midline and ±1 cm laterally, located at the prostate base, midgland, and apex. Associations of SQS with rectal dosimetry and late toxicity were evaluated. Results: The majority of the analyzed cohort had an SQS of 1 (n = 17; 41%) or 2 (n = 18; 43%). SQS was associated with maximum rectal point dose (rectal Dmax; P = .002), maximum dose to 1 cc of rectum (D1cc; P = .004), and volume of rectum receiving ≥100% of prescription dose (V45; P = .046) and ≥40 Gy (V40; P = .005). SQS was also associated with a higher incidence of (P = .01) and highest-graded late rectal toxicity (P = .01). Among the 20 men who developed late grade ≥1 rectal toxicity, 57%, 71%, and 22% had an SQS of 0, 1, and 2, respectively. Men with an SQS of 0 or 1 compared with 2 had 4.67-fold (95% CI, 0.72-30.11) or 8.40-fold (95% CI, 1.83-38.57) greater odds, respectively, of developing late rectal toxicity. Conclusions: We developed a reliable and informative metric for assessing HSP, which appears to be associated with rectal dosimetry and late rectal toxicity after prostate SBRT.

Phase II Randomized Study of Salvage Radiation Therapy Plus Enzalutamide or Placebo for High-Risk Prostate-Specific Antigen Recurrent Prostate Cancer After Radical Prostatectomy: The SALV-ENZA Trial.

PURPOSE: We sought to investigate whether enzalutamide (ENZA), without concurrent androgen deprivation therapy, increases freedom from prostate-specific antigen (PSA) progression (FFPP) when combined with salvage radiation therapy (SRT) in men with recurrent prostate cancer after radical prostatectomy (RP). PATIENTS AND METHODS: Men with biochemically recurrent prostate cancer after RP were enrolled into a randomized, double-blind, phase II, placebo-controlled, multicenter study of SRT plus ENZA or placebo (ClinicalTrials.gov identifier: NCT02203695). Random assignment (1:1) was stratified by center, surgical margin status (R0 v R1), PSA before salvage treatment (PSA ≥ 0.5 v < 0.5 ng/mL), and pathologic Gleason sum (7 v 8-10). Patients were assigned to receive either ENZA 160 mg once daily or matching placebo for 6 months. After 2 months of study drug therapy, external-beam radiation (66.6-70.2 Gy) was administered to the prostate bed (no pelvic nodes). The primary end point was FFPP in the intention-to-treat population. Secondary end points were time to local recurrence within the radiation field, metastasis-free survival, and safety as determined by frequency and severity of adverse events. RESULTS: Eighty-six (86) patients were randomly assigned, with a median follow-up of 34 (range, 0-52) months. Trial arms were well balanced. The median pre-SRT PSA was 0.3 (range, 0.06-4.6) ng/mL, 56 of 86 patients (65%) had extraprostatic disease (pT3), 39 of 86 (45%) had a Gleason sum of 8-10, and 43 of 86 (50%) had positive surgical margins (R1). FFPP was significantly improved with ENZA versus placebo (hazard ratio [HR], 0.42; 95% CI, 0.19 to 0.92; P = .031), and 2-year FFPP was 84% versus 66%, respectively. Subgroup analyses demonstrated differential benefit of ENZA in men with pT3 (HR, 0.22; 95% CI, 0.07 to 0.69) versus pT2 disease (HR, 1.54; 95% CI, 0.43 to 5.47; Pinteraction = .019) and R1 (HR, 0.14; 95% CI, 0.03 to 0.64) versus R0 disease (HR, 1.00; 95% CI, 0.36 to 2.76; Pinteraction = .023). There were insufficient secondary end point events for analysis. The most common adverse events were grade 1-2 fatigue (65% ENZA v 53% placebo) and urinary frequency (40% ENZA v 49% placebo). CONCLUSION: SRT plus ENZA monotherapy for 6 months in men with PSA-recurrent high-risk prostate cancer after RP is safe and delays PSA progression relative to SRT alone. The impact of ENZA on distant metastasis or survival is unknown at this time.

Alterations in BRCA2 as Determinants of Therapy Response in Prostate Cancer.

Prostate cancer (PCa) is one of the leading causes of cancer diagnoses and cancer-related deaths in the United States. Mutations or deletions in the genes involved in the DNA damage response (DDR) are common in aggressive primary PCa (germline alterations) and further enriched in advanced therapy-resistant PCa (somatic alterations). Among the DDR genes, BRCA2 is the most commonly altered (~ 13%) in advanced therapy-resistant PCa. Patients with BRCA2-altered PCas are exquisitely sensitive to poly (ADP-ribose) polymerase (PARP) inhibitors (PARPis). Indeed, two PARPis-olaparib and rucaparib have recently gained U.S. Food & Drug Administration approval for the treatment of advanced PCas harboring a BRCA2 mutation. This review seeks to explore the role of BRCA2 in DNA damage repair, the pathogenesis and progression of BRCA2 mutant PCa, and the utility of radiation therapy, targeted therapies, and platinum-based chemotherapies for patients with BRCA2 alterations.

Case Report: Adaptive radiotherapy in the radiation salvage of prostate cancer.

Adaptive radiotherapy has the potential to reduce margins, improve target coverage, and decrease toxicity to organs at risk (OARs) by optimizing radiation delivery to daily anatomic changes. Salvage for locally recurrent prostate cancer after definitive radiation remains a challenging clinical scenario given the risks to normal tissue in a setting of re-irradiation. Here, we present a case series of five patients with locally recurrent prostate cancer treated with an adaptive online linear accelerator or a 3-T MR-based linear accelerator to demonstrate excellent target coverage. All patients completed the planned treatment course with acceptable acute toxicities but a short follow-up time does not inform subacute/late toxicities.

Primary central nervous system lymphoma: a real-world comparison of therapy access and outcomes by hospital setting.

Background: This study analyzes sociodemographic barriers for primary CNS lymphoma (PCNSL) treatment and outcomes at a public safety-net hospital versus a private tertiary academic institution. We hypothesized that these barriers would lead to access disparities and poorer outcomes in the safety-net population. Methods: We reviewed records of PCNSL patients from 2007-2020 (n = 95) at a public safety-net hospital (n = 33) and a private academic center (n = 62) staffed by the same university. Demographics, treatment patterns, and outcomes were analyzed. Results: Patients at the safety-net hospital were significantly younger, more commonly Black or Hispanic, and had a higher prevalence of HIV/AIDS. They were significantly less likely to receive induction chemotherapy (67% vs 86%, P = .003) or consolidation autologous stem cell transplantation (0% vs. 47%, P = .001), but received more whole-brain radiation therapy (35% vs 16%, P = .001). Younger age and receiving any consolidation therapy were associated with improved progression-free (PFS, P = .001) and overall survival (OS, P = .001). Hospital location had no statistical impact on PFS (P = .725) or OS (P = .226) on an age-adjusted analysis. Conclusions: Our study shows significant differences in treatment patterns for PCNSL between a public safety-net hospital and an academic cancer center. A significant survival difference was not demonstrated, which is likely multifactorial, but likely was positively impacted by the shared multidisciplinary care delivery between the institutions. As personalized therapies for PCNSL are being developed, equitable access including clinical trials should be advocated for resource-limited settings.

A Combined Biomarker of Bright CD38 and MYC ≥55% Is Highly Predictive of Double-/Triple-Hit High-Grade B-Cell Lymphoma.

OBJECTIVES: Diagnosis of high-grade B-cell lymphoma with MYC and BCL2 or BCL6 rearrangements (double-/triple-hit lymphoma [DTHL]) appears to mandate fluorescence in situ hybridization (FISH) testing for all large B-cell lymphoma (LBCL). Given the low incidence of DTHL, we aimed to identify flow cytometry (FC) and immunohistochemistry (IHC) features of DTHL that could be used to develop an optimal screening strategy. This combined FC-IHC approach has not yet been studied. METHODS: We compared features of 40 cases of DTHL and 39 cases of diffuse LBCL (DLBCL) without MYC rearrangement. RESULTS: Bright CD38 expression (CD38bright) by FC, high MYC expression (≥55%), and double-expressor phenotype by IHC were significantly associated with DTHL. The biomarker combining FC and IHC, CD38bright and/or MYC ≥55%, was superior to FC and IHC markers alone in predicting DTHL. Restricting FISH testing to approximately 25% of LBCL based on CD38brightand/or MYC ≥55% would detect approximately 95% of DTHL-BCL2 and approximately 75% of DHL-BCL6. CONCLUSIONS: Our study demonstrated that the novel biomarker of CD38bright and/or MYC ≥55% is highly predictive of DTHL. Awareness of the advantages and limitations of this screening strategy would facilitate development of a rational diagnostic workflow to provide high-quality patient care.

Dose-Intensified Stereotactic Ablative Radiation for Localized Prostate Cancer.

Purpose: Stereotactic ablative radiation (SAbR) has been increasingly used in prostate cancer (PCa) given its convenience and cost efficacy. Optimal doses remain poorly defined with limited prospective comparative trials and long-term safety/efficacy data at higher dose levels. We analyzed toxicity and outcomes for SAbR in men with localized PCa at escalated 45 Gy in 5 fractions. Methods and Materials: This study retrospectively analyzed men from 2015 to 2019 with PCa who received linear-accelerator-based SAbR to 45 Gy in 5 fractions, along with perirectal hydrogel spacer, fiducial placement, and MRI-based planning. Disease control outcomes were calculated from end of treatment. Minimally important difference (MID) assessing patient-reported quality of life was defined as greater than a one-half standard deviation increase in American Urological Association (AUA) symptom score after SAbR. Results: Two-hundred and forty-nine (249) low-, intermediate-, and high-risk PCa patients with median follow-up of 14.9 months for clinical toxicity were included. Acute urinary grade II toxicity occurred in 20.4% of patients. Acute grade II GI toxicity occurred in 7.3% of patients. For follow-up > 2 years (n = 69), late GU and GI grade ≥III toxicity occurred in 5.8% and 1.5% of patients, respectively. MID was evident in 31.8%, 23.4%, 35.8%, 37.0%, 33.3%, and 26.7% of patients at 3, 6, 12, 24, 36, and 48 months, respectively. The median follow-up for biochemical recurrence was 22.6 months with biochemical failure-free survival of 100% at 1 year (n = 226) and 98.7% for years 2 (n = 113) and 3 (n = 54). Conclusions: SAbR for PCa at 45 Gy in 5 fractions shows an encouraging safety profile. Prospective studies with longer follow-up are warranted to establish this dose regimen as standard of care for PCa.

ACR-ACNM-ASTRO-SNMMI Practice Parameter for Lutetium-177 (Lu-177) DOTATATE Therapy.

OBJECTIVES: This practice parameter (PP) for Lutetium-177 (Lu-177) DOTATATE peptide receptor radionuclide therapy (PRRT) aims to guide authorized users in selection of appropriate adult candidates with gastroeneropancreatic neuroendocrine tumors (GEP-NETs) from foregut, midgut, and hindgut. The essential selection criteria include somatostatin receptor-positive GEP-NETs, which are usually inoperable and progressed despite standard therapy. Lu-177 DOTATATE is a radiopharmaceutical with high avidity for somatostatin receptors that are overexpressed by these tumors. This document ensures safe handling of Lu-177 DOTATATE by the authorized users and safe management of affected patients. METHODS: The document was developed according to the systematic process developed by the American College of Radiology (ACR) and described on the ACR Web site (https://www.acr.org/Clinical-Resources/Practice-Parameters-and-Technical-Standards). The PP development was led by 2 ACR Committees on Practice Parameters (Nuclear Medicine and Molecular Imaging and Radiation Oncology) collaboratively with the American College of Nuclear Medicine, American Society of Radiation Oncology, and Society of Nuclear Medicine and Molecular Imaging. RESULTS: The Lu-177 DOTATATE PP reviewed pharmacology, indications, adverse effects, personnel qualifications, and required clinical evaluation before starting the treatment, as well as the recommended posttherapy monitoring, quality assurance, documentation, and appropriate radiation safety instructions provided in written form and explained to the patients. CONCLUSIONS: Lu-177 DOTATATE is available for therapy of inoperable and/or advanced GEP-NETs when conventional therapy had failed. It can reduce tumor size, improve symptoms, and increase the progression free survival. The PP document provides clinical guidance for authorized users to assure an appropriate, consistent, and safe practice of Lu-177 DOTATATE.