Proton therapy for high-risk prostate cancer: Results from the Proton Collaborative Group PCG 001-09 prospective registry trial.

BACKGROUND: Data for proton therapy in high-risk prostate cancer (HRPC) are limited. Using the Proton Collaborative Group prospective registry, we evaluated outcomes for HRPC patients treated with proton therapy. METHODS: A totsl of 605 men with localized HRPC treated with proton therapy from 8/2009 to 3/2019 at nine institutions were selected. Outcomes examined included freedom from progression (FFP), metastasis free survival (MFS), overall survival (OS), and toxicity. Multivariable cox/binomial regression models were used to assess predictors of FFP and toxicity. RESULTS: Median age was 71 years. Gleason grade groups 4 (49.4%) and 5 (31.7%) were most common, as were clinical stage T1c (46.1%) and cT2 (41.3%). The median pretreatment prostate specific antigen (PSA) was 9.18 and median International Prostate Symptom Score (IPSS) was 6. Androgen deprivation therapy was given in 63.6%. Median dose was 79.2 GyE in 44 fractions. Pelvic lymph nodes were treated in 58.2% of cases. Pencil beam scanning was used in 54.5%, uniform scanning in 38.8%, and a rectal spacer in 14.2%. At a median followup of 22 months, the 3- and 5-year FFP were 90.7% and 81.4%, respectively. Five-year MFS and OS were 92.8% and 95.9%, respectively. Independent correlates of FFP included Gleason ≥8, PSA > 10, and cT2 (all p < 0.05). No grade 4 or 5 adverse events were reported. There were 23 (5%) grade 2 and 0 grade 3 gastrointestinal events. Prevalence of late grade 3, late grade 2, acute grade 3, and acute grade 2 genitourinary toxicity was 1.7%, 5.8%, 0%, and 21.8%, respectively. Prevalence of grade 2 and 3 erectile dysfunction at 2 years was 48.4% and 8.4%, respectively. CONCLUSIONS: In the largest series published to date, our results suggest early outcomes using proton therapy for HRPC are encouraging for both safety and efficacy. Further evaluation is needed to determine if an advantage exists to use protons over other radiation techniques in this population.

Using patient-specific bolus for pencil beam scanning proton treatment of periorbital disease.

PURPOSE: A unique mantle cell lymphoma case with bilateral periorbital disease unresponsive to chemotherapy and with dosimetry not conducive to electron therapy was treated with pencil beam scanning (PBS) proton therapy. This patient presented treatment planning challenges due to the thin target, immediately adjacent organs at risk (OAR), and nonconformal orbital surface anatomy. Therefore, we developed a patient-specific bolus and hypothesized that it would provide superior setup robustness, dose uniformity and dose conformity. MATERIALS/METHODS: A blue-wax patient-specific bolus was generated from the patient's face contour to conform to his face and eliminate air gaps. A relative stopping power ratio (RSP) of 0.972 was measured for the blue-wax, and the HUs were overridden accordingly in the treatment planning system (TPS). Orthogonal kV images were used for bony alignment and then to ensure positioning of the bolus through fiducial markers attached to the bolus and their contours in TPS. Daily CBCT was used to confirm the position of the bolus in relation to the patient's surface. Dosimetric characteristics were compared between (a) nonbolus, (b) conventional gel bolus and (c) patient-specific bolus plans. An in-house developed workflow for assessment of daily treatment dose based on CBCT images was used to evaluate inter-fraction dose accumulation. RESULTS: The patient was treated to 24 cobalt gray equivalent (CGE) in 2 CGE daily fractions to the bilateral periorbital skin, constraining at least 50% of each lacrimal gland to under 20 Gy. The bolus increased proton beam range by adding 2-3 energy layers of different fields to help achieve better dose uniformity and adequate dose coverage. In contrast to the plan with conventional gel bolus, dose uniformity was significantly improved with patient-specific bolus. The global maximum dose was reduced by 7% (from 116% to 109%). The max and mean doses were reduced by 6.0% and 7.7%, respectively, for bilateral retinas, and 3.0% and 13.9% for bilateral lacrimal glands. The max dose of the lens was reduced by 2.1%. The rigid shape, along with lightweight, and smooth fit to the patient face was well tolerated and reported as "very comfortable" by the patient. The daily position accuracy of the bolus was within 1 mm based on IGRT marker alignment. The daily dose accumulation indicates that the target coverage and OAR doses were highly consistent with the planning intention. CONCLUSION: Our patient-specific blue-wax bolus significantly increased dose uniformity, reduced OAR doses, and maintained consistent setup accuracy compared to conventional bolus. Quality PBS proton treatment for periorbital tumors and similar challenging thin and shallow targets can be achieved using such patient-specific bolus with robustness on both setup and dosimetry.

Optimal timing of chemoradiotherapy after surgical resection of glioblastoma: Stratification by validated prognostic classification.

BACKGROUND: Previous studies examining the time to initiate chemoradiation (CRT) after surgical resection of glioblastoma have been conflicting. To better define the effect that the timing of adjuvant treatment may have on outcomes, the authors examined patients within the National Cancer Database (NCDB) stratified by a validated prognostic classification system. METHODS: Patients with glioblastoma in the NCDB who underwent surgery and CRT from 2004 through 2013 were analyzed. Radiation Therapy Oncology Group recursive partitioning analysis (RPA) class (III, IV, V) was extrapolated for the cohort. Time intervals were grouped weekly, with weeks 4 to 5 serving as the reference category for analyses. Kaplan-Meier analysis, log-rank testing, and multivariate (MVA) Cox proportional hazards regression were performed. RESULTS: In total, 30,414 patients were included. RPA classes III, IV, and V contained 5250, 20,855, and 4309 patients, respectively. On MVA, no time point after week 5 was associated with a change in overall survival for the entire cohort or for any RPA class subgroup. The periods of weeks 0 to 1 (hazard ratio [HR], 1.18; 95% CI, 1.02-1.36), >1 to 2 (HR, 1.23; 95% CI, 1.16-1.31), and >2 to 3 (HR, 1.11; 95% CI, 1.07-1.15) demonstrated slightly worse overall survival (all P < .03). The detriment to early initiation was consistent across each RPA class subgroup. CONCLUSIONS: The current data provide insight into the optimal timing of CRT in patients with glioblastoma and describe RPA class-specific outcomes. In general, short delays beyond 5 weeks did not negatively affect outcomes, whereas early initiation before 3 weeks may be detrimental.

Microsatellite Instability (MSI) as an Independent Predictor of Pathologic Complete Response (PCR) in Locally Advanced Rectal Cancer: A National Cancer Database (NCDB) Analysis.

OBJECTIVE: The relationship between microsatellite instability (MSI) and response to neoadjuvant chemoradiation in rectal cancer is not well understood. BACKGROUND: We utilized the National Cancer Database (NCDB) to investigate the association between MSI and pathologic complete response (pCR) in this patient population. METHODS: We analyzed 5086 patients between 2010 and 2015 with locally advanced rectal cancer who were tested for MSI and treated definitively with chemoradiation followed by surgery. Primary comparison groups were between 4450 MSI-negative(-) and 636 MSI-positive(+) patients. Multivariable regression analysis was conducted to identify demographic, therapeutic, and clinical characteristics predictive of pCR. Cox proportional-hazard ratios were used for survival. RESULTS: All patients were treated with definitive chemoradiation (median dose 50.4 Gy) followed by resection within 4 months. MSI(+) patients were associated with earlier year of diagnosis and higher-grade tumors (P < 0.05).The overall pCR rate was 8.6%, including 8.9% for MSI(-) and 5.9% for MSI(+) tumors (P = 0.01). Along with lower T stage, MSI(+) cases were significantly associated with a reduced pCR rate (odds ratio 0.65, 95% confidence interval 0.43-0.96) with multivariable analysis. The 5-year survival for patients with pCR was 93% compared with 73% without it (<0.001). CONCLUSION: Microsatellite instability was independently associated with a reduction in pCR for locally advanced rectal cancer after neoadjuvant chemoradiation in this NCDB-based analysis.

Race-driven survival differential in women diagnosed with endometrial cancers in the USA.

OBJECTIVE: African American women are increasingly being diagnosed with advanced and type II histology endometrial cancers. Outcomes have been observed to be worse in African American women, but whether or not race itself is a factor is unclear. We sought to evaluate the rates of diagnosis and outcomes on a stage-by-stage basis with respect to race using a large national cancer registry database. METHODS: The National Cancer Data Base was searched for patients with surgically staged non-metastatic endometrial cancer between 2004 and 2015. Women were excluded if surgical stage/histology was unknown, there was no follow-up, or no information on subsequent treatment. Pairwise comparison was used to determine temporal trends and Cox hazards tests with Bonferroni correction were used to determine overall survival. RESULTS: A total of 286 920 women were diagnosed with endometrial cancer and met the criteria for analysis. Median follow-up was 51 months (IQR 25.7-85.3). In multivariable models, in women with stage I disease, African American women had a higher risk of death than Caucasian women (HR 1.262, 95% CI 1.191 to 1.338, p<0.001) and Asian/Pacific Islander women had a lower risk of death than Caucasian women (HR 0.742, 95% CI 0.689 to 0.801, p<0.001). This held for African American women with stage II type I and type II disease (HR 1.26, 95% CI 1.109 to 1.444, p<0.001 and HR 1.235, 95% CI 1.098 to 1.388, p<0.001) but not for Asian/Pacific Islander women. African American women with stage IIIA-B disease also had a higher risk of death for type I and type II disease versus Caucasian women (HR 1.221, 95% CI 1.045 to 1.422, p=0.010 and HR 1.295, 95% CI 1.155 to 1.452, p<0.001). Asian/Pacific Islander women had a lower risk of death than Caucasian women with type I disease (HR 0.783, 95% CI 0.638 to 0.960, p=0.019) and type II disease (HR 0.790, 95% CI 0.624 to 0.999, p=0.05). African American women with stage IIIC1-2 had a higher risk of death with type I disease (HR 1.343, 95% CI 1.207 to 1.494, p<0.001) and type II disease (HR 1.141, 95% CI 1.055 to 1.233, p=0.001) whereas there was no significant difference between Caucasian women and Asian/Pacific Islander women. CONCLUSION: Race appears to play an independent role in survival from endometrial cancer in the USA, with African American women having worse survival on a stage-for-stage basis compared with Caucasian women.

Liver transplant mortality and morbidity following preoperative radiotherapy for hepatocellular carcinoma.

BACKGROUND: Radiotherapy (RT) can be used for tumor downstaging and as a bridge to transplantation in hepatocellular carcinoma (HCC), but its effect on surgical complications is unknown. Therefore, we investigated post-transplant mortality and acute readmission rates in HCC with and without preoperative RT using the National Cancer Database (NCDB). METHODS: After exclusion, 11,091 transplant patients were analyzed, 165 of whom received RT prior to transplant. Multivariable binomial logistic regression analysis identified characteristics associated with use of RT, and factors associated with increased 30/90-day mortality and 30-day readmission, following propensity matching. RESULTS: Although RT (median 40 Gy in 5 fractions) was more often delivered to larger tumors and advanced stages, it resulted in 59% downstaging rate, 39% pathologic complete response rate, and a median of 4 additional months to transplantation. Crude 30/90-day mortality rates were both 1.2% with preoperative RT, compared to 2.7% and 4.4% without. The 30-day readmission rate was 5.5% with RT and 10.7% without it. Propensity matched analysis demonstrated no statistical differences in 30/90-day mortality and a lower 30-day readmission rate with preoperative RT. Age >58, stage III disease, lack of transarterial chemoembolization, and shorter time to transplant independently predicted higher 90-day mortality. CONCLUSION: Preoperative RT for HCC did not increase postoperative mortality or length of stay following liver transplant.

Management of Malignant Pleural Mesothelioma in the Elderly Population.

BACKGROUND: The median age at diagnosis for malignant pleural mesothelioma (MPM) is approximately 72 years. Elderly patients pose unique management challenges because of the increased risk of therapy-related toxicities and mortality. Because there are no high-volume retrospective studies, prospective trials, or dedicated treatment recommendations for this population, this investigation addresses a major knowledge gap by examining national practice patterns and postoperative/survival outcomes in elderly MPM patients. METHODS: The National Cancer Database was queried for patients aged ≥ 80 years with newly diagnosed nonmetastatic MPM. Multivariable logistic regression ascertained factors associated with observation and surgery. Kaplan-Meier analysis assessed overall survival (OS), and multivariable Cox proportional hazards modeling examined factors associated with OS. Survival was also calculated following propensity matching. Additionally, postoperative outcomes were evaluated in surgical patients. RESULTS: Of 4526 patients, 2% received surgery and chemotherapy, 22% underwent chemotherapy alone, and 63% were observed. Respective median OS was 12.2, 9.5, and 4.1 months (p < 0.001). Differences between all groups persisted following propensity matching (all comparisons p < 0.05). For the 8% of patients who underwent specified definitive surgery (95% of whom received pleurectomy/decortication), 30- and 90-day mortality rates were 11.0% and 28.5%, respectively. The median length of postoperative hospitalization was 6 days, with 30-day readmission occurring in 7.5% of patients. CONCLUSIONS: The majority of elderly MPM patients in the US are observed, which was associated with poorer OS than chemotherapy and/or surgery. Although highly selected surgery/chemotherapy patients were associated with the longest OS, given the high biases in database studies and high perioperative mortality rates, careful patient selection for combined modality approaches in this population is imperative.

Definitive Chemoradiation for Rectal Cancer: Is There a Role for Dose Escalation? A National Cancer Database Study.

BACKGROUND: Surgery remains the standard of care in rectal cancer. Select patients will not undergo surgery for reasons such as medical inoperability or a watch-and-wait approach and instead are managed with definitive chemoradiation. OBJECTIVE: We used the National Cancer Database to identify overall survival and predictors thereof in the nonoperative management of patients with rectal cancer. DESIGN: This was a retrospective review. SETTINGS: This study used deidentified data from the National Cancer Database. PATIENTS: We queried the national cancer database from 2004 to 2014 for stage 1 to 3 rectal adenocarcinoma treated with only chemotherapy and radiation to definitive doses. Dose escalated therapy was defined as >54 Gy. MAIN OUTCOME MEASURES: Univariable and multivariable analyses were performed to identify sociodemographic, treatment, and tumor characteristics predictive of dose escalation and overall survival. Propensity-adjusted Cox proportional hazard ratios for survival were used to account for indication bias. RESULTS: Among the 6311 patients eligible for the study, 11% were treated with doses >54 Gy. Earlier stage and increased age/comorbidity patients were more likely to receive dose escalation, and patients with more recent treatment and treatment at an academic facility were less likely. The median follow-up time was 31 months (range, 2-154 mo). Three- and 5-year overall survival rates for all patients were 60% and 46%. Patients treated with dose escalation had a median survival of 33 months compared with 56 months for those treated with ≤54 Gy (p < 0.0001). LIMITATIONS: The main limitation is the inherent selection bias present in National Cancer Database studies. Important treatment details and outcomes as they relate to a definitive chemoradiation approach in rectal cancer are lacking. Salvage therapy was also not recorded, which in this population could be surgery. CONCLUSIONS: In this analysis, dose escalation in the nonoperative management of rectal cancer was associated with a lower overall survival compared with more conventional doses. Careful patient selection and enrollment on appropriate clinical trials may be warranted in the nonoperative setting. See Video Abstract at http://links.lww.com/DCR/B15. LA QUIMIORRADIACIÓN DEFINITIVA PARA EL CÁNCER RECTAL: ¿HAY LUGAR PARA EL AUMENTO DE LA DOSIS? UN ESTUDIO DE BASE DE DATOS NACIONAL DEL CÁNCER:: La cirugía sigue siendo el estándar en el tratamiento del cáncer rectal. Algunos pacientes no son quirúrgicos por razones como, no ser operables o con el enfoque de ver y esperar, y en su lugar son tratados con la quimiorradiación definitiva.Utilizamos la base de datos nacional del cáncer para identificar la supervivencia general y los factores predictivos de la misma, en el tratamiento no quirúrgico de pacientes con cáncer rectal.Esta fue una revisión retrospectiva.Utilizamos los datos identificados en la base de datos nacional del cáncer.Se consultó la base de datos nacional del cáncer del 2004-2014, para adenocarcinoma rectal en estadio 1-3, tratada únicamente con quimioterapia y radiación hasta la dosis definitiva. La terapia de aumento de la dosis se definió como >54 Gy.Se realizaron análisis univariables y multivariables para identificar características sociodemográficas, de tratamiento y predictivas del aumento de la dosis y supervivencia en general. Los índices de riesgo proporcionales de Cox ajustados a la propensión para la supervivencia, se utilizaron para tener en cuenta el sesgo de indicación.Entre los 6311 pacientes elegibles para el estudio, el 11% fue tratado con dosis >54 Gy. Los pacientes en estadios tempranos y con mayor edad/comorbilidad, tenían más probabilidades de recibir aumento de la dosis, y menos propensos los pacientes con tratamientos recientes y de centros académicos. El tiempo medio de seguimiento fue de 31 meses (2-154 meses). Las tasas de supervivencia global de tres y cinco años para todos los pacientes, fueron respectivamente del 60% y 46%. Los pacientes tratados con aumento de la dosis, tuvieron una supervivencia media de 33 meses, en comparación con los 56 meses para los pacientes tratados con ≤54 Gy (p < 0,0001).La principal limitación es el inherente sesgo en la selección, presente en los estudios de la base de datos nacional del cáncer. Faltan los detalles importantes del tratamiento y los resultados en relación con el enfoque definitivo de quimiorradiación en cáncer rectal. Tampoco se registró la terapia de rescate, que en esta población podría ser la cirugía.En este análisis, el aumento de la dosis en el manejo no quirúrgico del cáncer rectal, se asoció con una menor supervivencia global, en comparación con la dosis más convencional. La cuidadosa selección del paciente y la inscripción en los apropiados ensayos clínicos, pueden estar justificados en el entorno no quirúrgico. Vea el Resumen del Video en http://links.lww.com/DCR/B15.

Management of brain metastases from large cell neuroendocrine carcinoma of the lung: improved outcomes with radiosurgery.

OBJECTIVES: Large cell neuroendocrine carcinoma (LCNEC) of the lung is a rare pulmonary tumor, having similar natural history and management strategy as small cell lung cancer. Therefore, the management of brain metastases in these patients has mirrored that of SCLC through the use of whole brain radiation therapy (WBRT). We used the National Cancer Database (NCDB) to look at predictors of stereotactic radiosurgery (SRS) and any potential differences in outcomes for patients with brain metastases from LCNEC. MATERIAL AND METHODS: We queried the NCDB from 2004 to 2015 for patients with LCNEC of the lung with brain metastases that received brain radiation. Univariable and multivariable analyses were performed to identify factors predictive of SRS use and overall survival (OS). Propensity-adjusted Cox proportional hazard ratios for survival were used to account for indication bias. RESULTS: Out of 9970 patients with LCNEC of the lung we identified 348 with brain metastases. Sixty-eight patients were treated with upfront SRS and 280 were treated with WBRT. Patients that were treated at an academic facility or received chemotherapy as part of upfront treatment were more likely to receive SRS. Univariable analysis revealed improved outcomes with SRS compared to WBRT, with a median OS of 11 months compared to 6 months, respectively (p = .007). Multivariable Cox regression with propensity score confirmed SRS to have improved survival (HR: 0.68, 95%CI: 0.51-0.91, p = .0093). Multivariable Cox regression with propensity score also identified younger age, receipt of chemotherapy, absence of extracranial disease and non-rural locations as additional predictors of improved OS. CONCLUSIONS: Treatment of brain metastases from LCNEC of the lung with SRS was associated with improved survival. For the appropriate patients, upfront treatment of limited brain metastases with SRS may be appropriate.

Management trends and outcomes of breast angiosarcoma: Is breast conservation feasible?

We queried the National Cancer Database for nonmetastatic breast angiosarcoma, yielding 808 patients (202 de novo, 606 secondary). The median survival was 53.7 months. Secondary tumors were more likely to undergo mastectomy than de novo lesions (OR = 3.99, P < 0.001). Treatments included lumpectomy (10%), lumpectomy/radiation (3%), mastectomy alone (73%), or mastectomy/radiation (14%), with no difference in survival (P = 0.68). Lumpectomy correlated with positive margin rate (OR 3.29), which was a predictor for death (HR = 2.37, P < 0.01), along with older age, higher comorbidity scores, size >5 cm, and high-grade disease (P < 0.05). While breast angiosarcoma is usually treated with mastectomy, lumpectomy may be feasible for well-selected tumors.

Grover's Disease Treated With Total Skin Electron Beam Radiotherapy

Persistent Grover's disease can cause significant symptoms of pruritus thereby decreasing quality of life. Many patients undergo successful conservative management of their disease; however, a subset of patients is recalcitrant despite multiple lines of therapy. Accordingly, we present, to our knowledge, the first reported case of recalcitrant Grover's disease treated successfully with radiotherapy. J Drugs Dermatol. 2019;18(4):392-393.

Re-Irradiation with Stereotactic Radiosurgery/Radiotherapy for Recurrent High-Grade Gliomas: Improved Survival in the Modern Era.

OBJECTIVE: The aim of this study was to evaluate the efficacy of stereotactic radiosurgery (SRS) and fractionated stereotactic radiotherapy (fSRT) as salvage therapy for recurrent high-grade glioma and to look at the overall efficacy of treatment with linear accelerator (LINAC)-based radiosurgery and fractionated radiotherapy. METHODS: From 2010 to 2017, a total of 25 patients aged 23-74 years were re-irradiated with LINAC-based SRS and fSRT. Patients were treated to a median dose of 25 Gy in 5 fractions. RESULTS: The median overall survival (OS) after (initial) diagnosis was 39 months with an actuarial 1-, 3-, and 5-year OS rate of 88, 56, and 30%, respectively. After treatment with SRS or fSRT, the median OS was 9 months with an actuarial 1-year OS rate of 29%. Local control, assessed for 28 tumors, after 6 months was 57%, while local control after 1 year was 39%. Three patients experienced local failure. There was no evidence of toxicity noted after SRS or fSRT throughout the follow-up period. CONCLUSION: SRS and fSRT remain a safe, reasonable, effective treatment option for re-irradiation following recurrent glioblastoma. Additionally, treatment volume may predict local control in the salvage setting.

Advancing knowledge-based intensity modulated proton planning for adaptive treatment of high-risk prostate cancer.

To assess the performance of a knowledge-based planning (KBP) model for generating intensity-modulated proton therapy (IMPT) treatment plans as part of an adaptive radiotherapy (ART) strategy for patients with high-risk prostate cancer. A knowledge-based planning (KBP) model for proton adaptive treatment plan generation was developed based on thirty patient treatment plans utilizing RapidPlanTM PT (Varian Medical Systems, Palo Alto, CA). The model was subsequently validated using an additional eleven patient cases. All patients in the study were administered a prescribed dose of 70.2 Gy to the prostate and seminal vesicle (CTV70.2), along with 46.8 Gy to the pelvic lymph nodes (CTV46.8) through simultaneous integrated boost (SIB) technique. To assess the quality of the validation knowledge-based proton plans (KBPPs), target coverage and organ-at-risk (OAR) dose-volume constraints were compared against those of clinically used expert plans using paired t-tests. The KBP model training statistics (R2) (mean ± SD, 0.763 ± 0.167, range, 0.406 to 0.907) and χ² values (1.162 ± 0.0867, 1.039-1.253) indicate acceptable model training quality. Moreover, the average total treatment planning optimization and calculation time for adaptive plan generation is approximately 10 minutes. The CTV70.2 D98% for the KBPPs (mean ± SD, 69.1 ± 0.08 Gy) and expert plans (69.9 ± 0.04 Gy) shows a significant difference (p < 0.05) but are both within 1.1 Gy of the prescribed dose which is clinically acceptable. While the maximum dose for some organs-at-risk (OARs) such as the bladder and rectum is generally higher in the KBPPs, the doses still fall within clinical constraints. Among all the OARs, most of them received comparable results to the expert plan, except the cauda equina Dmax, which shows statistical significance and was lower in the KBPPs than in expert plans (48.5 ± 0.06 Gy vs 49.3 ± 0.05 Gy). The generated KBPPs were clinically comparable to manually crafted plans by expert treatment planners. The adaptive plan generation process was completed within an acceptable timeframe, offering a quick same-day adaptive treatment option. Our study supports the integration of KBP as a crucial component of an ART strategy, including maintaining plan consistency, improving quality, and enhancing efficiency. This advancement in speed and adaptability promises more precise treatment in proton ART.

Stereotactic Body Radiation Therapy (SBRT) for Hepatocellular Carcinoma (HCC) With Single Photon Emission Computed Tomography (SPECT) Functional Treatment Planning in Patients With Advanced Hepatic Cirrhosis.

Purpose: We report on the feasibility and outcomes of liver stereotactic body radiation therapy (SBRT) for hepatocellular carcinoma (HCC) with single-photon emission computed tomography (SPECT) functional treatment planning in patients with Child-Pugh (CP) B/C cirrhosis. Methods and Materials: Liver SPECT with 99mTc-sulfur colloid was coregistered to treatment planning computed tomography (CT) for the guided avoidance of functional hepatic parenchyma during SBRT. Functional liver volumes (FLVs) obtained from SPECT were compared with anatomic liver volumes defined on the planning CT. Radiation dose constraints were adapted exclusively to FLV. Local control, toxicity, and survival were reported with at least 6 months of radiographic follow-up. Pre- and posttransplant outcomes were analyzed in a subset of patients who completed SBRT as a bridge to liver transplant. Model of End-Stage Liver Disease was used to score hepatic function before and after SBRT completion. Results: With a median follow-up of 32 months, 45 patients (58 lesions) with HCC and CP-B/C cirrhosis received SBRT to a median dose of 45 Gy (3-5 fractions). FLV loss (34%, P < .001) was observed in all patients, and the functional and anatomic liver volumes matched well in a control group of noncirrhotic/non-HCC patients. Despite marked functional parenchyma retraction, the amount of FLV on SPECT exposed to the threshold irradiation was significantly less than the CT liver volumes (P < .001) because of the optimized beam placement during dosimetry planning. Twenty-three patients (51%) successfully completed orthotopic liver transplant, with a median time to transplant of 9.2 months. With 91% in-field local control, the overall 2-year survival was 65% (90% after the orthotopic liver transplant), with no incidence of radiation-induced liver disease observed within 3 to 4 months or accelerated CP class migration from B to C within the first 6 months post-SBRT. Mean Model of End-Stage Liver Disease-Na score was not significantly elevated at 3-month intervals after SBRT completion. Conclusions: Functional treatment planning with 99mTc sulfur colloid SPECT/CT allows identification and avoidance of functional hepatic parenchyma in patients with CP-B/C cirrhosis, leading to low toxicity and satisfactory transplant outcomes.

Differences in Patterns of Care and Referral Between Proton and Photon Therapy.

Purpose: To report demographic and clinical characteristics of patients who were more likely to receive proton beam therapy (PBT) than photon therapy from facilities with access to proton centers. Materials and Methods: We utilized the national cancer database to identify the facilities with access to PBT between 2004 and 2015 and compared the relative usage of photons and PBT for demographic and clinical scenarios in breast, prostate, and nonsmall cell cancer. Results: In total, 231 facilities with access to proton centers accounted for 168 323 breast, 39 975 lung, and 77 297 prostate cancer patients treated definitively. Proton beam therapy was used in 0.5%, 1.5%, and 8.9% of breast, lung, and prostate cases. Proton beam therapy was correlated with a farther distance traveled and longer start time from diagnosis for each site (P < .05).For breast, demographic correlates of PBT were treatment in the west coast (odds ratio [OR] = 4.81), age <60 (OR = 1.25), white race (OR = 1.94), and metropolitan area (OR = 1.58). Left-sided cancers (OR = 1.28), N2 (OR = 1.71), non-ER+/PR+/Her2Neu- cancers (OR = 1.24), accelerated partial breast irradiation (OR = 1.98), and hypofractionation (OR = 2.35) were predictors of PBT.For nonsmall cell cancer, demographic correlates of PBT were treatment in the south (OR = 2.6), metropolitan area (OR = 1.72), and Medicare insurance (OR = 1.64). Higher comorbid score (OR = 1.36), later year treated (OR = 3.16), and hypofractionation (not SBRT) (OR = 3.7) were predictors of PBT.For prostate, correlates of PBT were treatment in the west coast (OR = 2.48), age <70 (OR = 1.19), white race (OR = 1.41), metropolitan area (OR = 1.25), higher income/education (OR = 1.25), and treatment at an academic center (OR = 33.94). Lower comorbidity score (OR = 1.42), later year treated (OR = 1.37), low-risk disease (OR = 1.45), definitive compared to postoperative (OR = 6.10), and conventional fractionation (OR = 1.64) were predictors of PBT. Conclusion: Even for facilities with established referrals to proton centers, PBT utilization was low; socioeconomic status was potentially a factor. Proton beam therapy was more often used with left-sided breast and low-risk prostate cancers, without a clear clinical pattern in lung cancer.

Prognostic implications of HER2NEU-low in metastatic breast cancer.

INTRODUCTION: We explored characteristics and clinical outcomes of HER2-negative and HER2-low metastatic breast cancers using real-world data. METHODS: We queried the National Cancer Database to identify MBC patients that were HER2-low or HER2-negative per immunohistochemical staining. A binomial regression analysis identified demographic and clinical correlates of each subtype. A Cox multivariable regression analysis (MVA) and propensity-match analysis were performed to identify correlates of survival. RESULTS: Excluding missing data, 24,636 MBC patients diagnosed between 2008 and 2015 were identified; 27.9% were HER2-negative and 72.1% were HER2-low. There were no relevant demographic differences between the groups. HER2-low tumors were half as likely to have concomitant hormone receptor-positive status (p < 0.01). The 3-year survival rate among hormone receptor-negative patients was 33.8% for HER2-low and 32.2% for HER2-negative (p < 0.05), and 60.9% and 55.6% in HER2-low and HER2-negative cases among hormone receptor-positive patients (p < 0.05), respectively. HER2-low cases were associated with better survival on MVA (HR =0.95, 95% CI 0.91-0.99) and remained superior with propensity-matching (HR = 0.92, 95% CI 0.89-0.96). In a subset analysis isolated to hormone receptor-positive cases, HER2-low remained correlated with improved survival (HR = 0.93, 95% CI 0.89-0.98) with propensity-matched MVA. Correlates of worse survival include older age as a continuous variable (HR = 1.02, 95% CI 1.02-1.02) and Black race (HR = 1.26, 95% CI 1.20-1.32) [all p < 0.01]. CONCLUSIONS: In the largest such analysis performed to date, our study demonstrates a small but statistically significant association with improved survival for HER2-low tumors compared to HER2-negative tumors in MBC.

Combining theranostic/particle therapy with immunotherapy for the treatment of GU malignancies.

Particle therapy and radiopharmaceuticals are emerging fields in the treatment of genitourinary cancers. With these novel techniques and the ever-growing immunotherapy options, the combinations of these therapies have the potential to improve current cancer cure rates. However, the most effective sequence and combination of these therapies is unknown and is a question that is actively being explored in multiple ongoing clinical trials. Here, we review the immunological effects of particle therapy and the available radiopharmaceuticals and discuss how best to combine these therapies.

The potential role of precision medicine to alleviate racial disparities in prostate, bladder and renal urological cancer care.

Background: Racial disparities in oncological outcomes resulting from differences in social determinants of health (SDOH) and tumour biology are well described in prostate cancer (PCa) but similar inequities exist in bladder (BCa) and renal cancers (RCCs). Precision medicine (PM) aims to provide personalized treatment based on individual patient characteristics and has the potential to reduce these inequities in GU cancers. Objective: This article aims to review the current evidence outlining racial disparities in GU cancers and explore studies demonstrating improved oncological outcomes when PM is applied to racially diverse patient populations. Evidence acquisition: Evidence was obtained from Pubmed and Web of Science using keywords prostate, bladder and renal cancer, racial disparity and precision medicine. Because limited studies were found, preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines were not applied but rather related articles were studied to explore existing debates, identify the current status and speculate on future applications. Results: Evidence suggests addressing SDOH for PCa can reverse racial inequities in oncological outcomes but differences in incidence remain. Similar disparities in BCa and RCC are seen, and it would be reasonable to suggest achieving parity in SDOH for all races would do the same. Research applying a PM approach to different ethnicities is lacking although in African Americans (AAs) with metastatic castrate-resistant prostate cancer (mCRPCa) better outcomes have been shown with androgen receptor inhibitors, radium-223 and sipuleucel. Exploiting the abscopal effect with targeted radiation therapy (RT) and immunotherapy has promise but requires further study, as does defining actionable mutations in specific patient groups to tailor treatments as appropriate. Conclusion: For all GU cancers, the historical underrepresentation of ethnic minorities in clinical trials still exists and there is an urgent need for recruitment strategies to address this. PM is a promising development with the potential to reduce inequities in GU cancers, however, both improved understanding of race-specific tumour biology, and enhanced recruitment of minority populations into clinical trials are required. Without this, the benefits of PM will be limited.

Prospective evaluation of patient-reported outcomes of invisible ink tattoos for the delivery of external beam radiation therapy: the PREFER trial.

Introduction: Invisible ink tattoos (IITs) avoid cosmetic permanence of visible ink tattoos (VITs) while serving as more reliable landmarks for radiation setup than tattooless setups. This trial evaluated patient-reported preference and feasibility of IIT implementation. Methods and materials: In an IRB-approved, single institution, prospective trial, patients receiving proton therapy underwent IIT-based treatment setup. A survey tool assessed patient preference on tattoos using a Likert scale. Matched patients treated using our institutional standard tattooless setup were identified; treatment times and image guidance requirements were evaluated between tattooless and IIT-based alignment approaches. Distribution differences were estimated using Wilcoxon rank-sum tests or Chi-square tests. Results: Of 94 eligible patients enrolled, median age was 58 years, and 58.5% were female. Most common treatment sites were breast (18.1%), lung (17.0%) and pelvic (14.9%). Patients preferred to receive IITs versus VITs (79.8% pre-treatment and 75.5% post-treatment, respectively). Patients were willing to travel farther from home to avoid VITs versus IITs (p<0.01). Females were willing to travel (45.5% vs. 23.1%; p=0.04) and pay additional money to avoid VITs (34.5% vs. 5.1%; p<0.01). Per-fraction average +treatment time and time from on table/in room to first beam were shorter with IIT-based vs. tattooless setup (12.3min vs. 14.1min; p=0.04 and 24.1min vs. 26.2min; p=0.02, respectively). Discussion: In the largest prospective trial on IIT-based radiotherapy setup to date, we found that patients prefer IITs to VITs. Additionally, IIT-based alignment is an effective and efficient strategy in comparison with tattooless setup. Standard incorporation of IITs for patient setup should be strongly considered.

Pencil Beam Scanning Proton Bragg Peak Conformal FLASH in Prostate Cancer Stereotactic Body Radiotherapy.

Bragg peak FLASH radiotherapy (RT) uses a distal tracking method to eliminate exit doses and can achieve superior OAR sparing. This study explores the application of this novel method in stereotactic body radiotherapy prostate FLASH-RT. An in-house platform was developed to enable intensity-modulated proton therapy (IMPT) planning using a single-energy Bragg peak distal tracking method. The patients involved in the study were previously treated with proton stereotactic body radiotherapy (SBRT) using the pencil beam scanning (PBS) technique to 40 Gy in five fractions. FLASH plans were optimized using a four-beam arrangement to generate a dose distribution similar to the conventional opposing beams. All of the beams had a small angle of two degrees from the lateral direction to increase the dosimetry quality. Dose metrics were compared between the conventional PBS and the Bragg peak FLASH plans. The dose rate histogram (DRVH) and FLASH metrics of 40 Gy/s coverage (V40Gy/s) were investigated for the Bragg peak plans. There was no significant difference between the clinical and Bragg peak plans in rectum, bladder, femur heads, large bowel, and penile bulb dose metrics, except for Dmax. For the CTV, the FLASH plans resulted in a higher Dmax than the clinical plans (116.9% vs. 103.3%). For the rectum, the V40Gy/s reached 94% and 93% for 1 Gy dose thresholds in composite and single-field evaluations, respectively. Additionally, the FLASH ratio reached close to 100% after the application of the 5 Gy threshold in composite dose rate assessment. In conclusion, the Bragg peak distal tracking method can yield comparable plan quality in most OARs while preserving sufficient FLASH dose rate coverage, demonstrating that the ultra-high dose technique can be applied in prostate FLASH SBRT.