A customizable aluminum compensator system for total body irradiation.

PURPOSE: To develop a simplified aluminum compensator system for total body irradiation (TBI) that is easy to assemble and modify in a short period of time for customized patient treatments. METHODS: The compensator is composed of a combination of 0.3 cm thick aluminum bars, two aluminum T-tracks, spacers, and metal bolts. The system is mounted onto a plexiglass block tray. The design consists of 11 fixed sectors spanning from the patient's head to feet. The outermost sectors utilize 7.6 cm wide aluminum bars, while the remaining sectors use 2.5 cm wide aluminum bars. There is a magnification factor of 5 from the compensator to the patient treatment plane. Each bar of aluminum is interconnected at each adjacent sector with a tongue and groove arrangement and fastened to the T-track using a metal washer, bolt, and nut. Inter-bar leakage of the compensator was tested using a water tank and diode. End-to-end measurements were performed with an ion chamber in a solid water phantom and also with a RANDO phantom using internal and external optically stimulated luminescent detectors (OSLDs). In-vivo patient measurements from the first 20 patients treated with this aluminum compensator were compared to those from 20 patients treated with our previously used lead compensator system. RESULTS: The compensator assembly time was reduced to 20-30 min compared to the 2-4 h it would take with the previous lead design. All end-to-end measurements were within 10% of that expected. The median absolute in-vivo error for the aluminum compensator was 3.7%, with 93.8% of measurements being within 10% of that expected. The median error for the lead compensator system was 5.3%, with 85.1% being within 10% of that expected. CONCLUSION: This design has become the standard compensator at our clinic. It allows for quick assembly and customization along with meeting the Task Group 29 recommendations for dose uniformity.

The effect of radiation therapy on post-prostatectomy urinary function.

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

Commissioning an Elekta Versa HD linear accelerator.

The purpose of this study is to report the dosimetric aspects of commissioning performed on an Elekta Versa HD linear accelerator (linac) with high-dose-rate flattening filter-free (FFF) photon modes and electron modes. Acceptance and commissioning was performed on the Elekta Versa HD linac with five photon energies (6 MV, 10 MV, 18 MV, 6 MV FFF, 10 MV FFF), four electron energies (6 MeV, 9MeV, 12 MeV, 15 MeV) and 160-leaf (5 mm wide) multileaf collimators (MLCs). Mechanical and dosimetric data were measured and evaluated. The measurements include percent depth doses (PDDs), in-plane and cross-plane profiles, head scatter factor (Sc), relative photon output factors (Scp), universal wedge transmission factor, MLC transmission factors, and electron cone factors. Gantry, collimator, and couch isocentricity measurements were within 1 mm, 0.7 mm, and 0.7 mm diameter, respectively. The PDDs of 6 MV FFF and 10 MV FFF beams show deeper dmax and steeper falloff with depth than the corresponding flattened beams. While flatness values of 6 MV FFF and 10 MV FFF normalized profiles were expectedly higher than the corresponding flattened beams, the symmetry values were almost identical. The cross-plane penumbra values were higher than the in-plane penumbra values for all the energies. The MLC transmission values were 0.5%, 0.6%, and 0.6% for 6 MV, 10 MV, and 18 MV photon beams, respectively. The electron PDDs, profiles, and cone factors agree well with the literature. The outcome of radiation treatment is directly related to the accuracy in the dose modeled in the treatment planning system, which is based on the commissioned data. Commissioning data provided us a valuable insight into the dosimetric characteristics of the beam. This set of commissioning data can provide comparison data to others performing Versa HD commissioning, thereby improving patient safety.

A low-dose arsenic-induced p53 protein-mediated metabolic mechanism of radiotherapy protection.

Radiotherapy is the current frontline cancer treatment, but the resulting severe side effects often pose a significant threat to cancer patients, raising a pressing need for the development of effective strategies for radiotherapy protection. We exploited the distinct metabolic characteristics between normal and malignant cells for a metabolic mechanism of normal tissue protection. We showed that low doses of arsenic induce HIF-1α, which activates a metabolic shift from oxidative phosphorylation to glycolysis, resulting in increased cellular resistance to radiation. Of importance is that low-dose arsenic-induced HIF-1α requires functional p53, limiting the glycolytic shift to normal cells. Using tumor-bearing mice, we provide proof of principle for selective normal tissue protection against radiation injury.

Pathological characteristics of low risk prostate cancer based on totally embedded prostatectomy specimens.

BACKGROUND: Surveillance and focal therapy are increasingly considered for low risk prostate cancer (PC). We describe pathological characteristics of low risk PC at radical prostatectomy in contemporary patients. METHODS: Five-hundred-fifty-two men from 2008 to 2012 with low risk (stage T1c/T2a, PSA ≤ 10 ng/ml, Gleason score ≤6) PC underwent radical prostatectomy. Slides were re-reviewed to grade and stage the tumor, map separate tumor nodules, and calculate their volumes. RESULTS: Ninety-three (16.9%) men had prostatectomy Gleason score 3 + 4 = 7 or higher and were excluded. Five (0.9%) men had no residual carcinoma. Remaining 454 patients composed the study cohort. The median age was 57 years (36-73) and median PSA 4.4 ng/ml (0.4-9.9). Racial distribution was 77.5% Caucasian, 15.5% African American, and 7% other. The median total tumor volume was 0.38 cm(3) (0.003-7.22). Seventy percent of the patients had bilateral tumor and 34% had a tumor nodule >0.5 cm(3) . The index lesion represented 89% (median) of the total tumor volume. Extraprostatic extension and positive margin were present in 5.7% and 9% of cases, respectively. The tumor nodules measuring >0.5 cm(3) were located almost equally between the anterior (53%) and peripheral (47%) gland. The relationship between PSA and total tumor volume was weak (r = 0.13, P = 0.005). The relationship between PSA density and total tumor volume was slightly better (r = 0.26, P < 0.001). CONCLUSIONS: Low risk prostate cancer is generally a low volume disease. Gleason score upgrade is seen in 16.9% of cases at radical prostatectomy. While the index lesion accounts for the bulk of the disease, the cancer is usually multifocal and bilateral. Neither PSA nor PSA density correlates well with the total tumor volume. Prostate size has a significant contribution to PSA level. These factors need to be considered in treatment planning for low risk prostate cancer.

Tolerance of Phellodendron amurense bark extract (Nexrutine®) in patients with human prostate cancer.

Phellodendron amurense bark extract (Nexrutine®) has shown a favorable effect on prostate cancer in vivo and in vitro. We evaluated its tolerance in patients undergoing surgery or radiation for prostate cancer. Patients received Nexrutine® orally (500 mg tid) either 1 to 2 months preoperatively or 1 to 2 months prior to and with radiation therapy. Common Terminology Criteria for Adverse Events were used to measure tolerance. In total, 21 patients (9 surgery and 12 radiation) underwent treatment. During the Nexrutine® alone component, there were two transient grade 3 toxicities (hypokalemia and urinary incontinence). There was no grade 4 toxicity. For the combined Nexrutine® and radiation component, no additional patients suffered a grade 3 toxicity. All the toxicities were transient. By the end of the neoadjuvant treatment, 81% of the patients had a decline in prostate-specific antigen. This is the first report of patients with prostate cancer being treated with P. amurense bark extract, and it was very well tolerated. Toxicities were minimal and self-limited. This compound can be safely used in further evaluation of a treatment effect on cancer.

Evaluation of Dosimetry Check software for IMRT patient-specific quality assurance.

The purpose of this study is to evaluate the use of the Dosimetry Check system for patient-specific IMRT QA. Typical QA methods measure the dose in an array dosimeter surrounded by homogenous medium for which the treatment plan has been recomputed. With the Dosimetry Check system, fluence measurements acquired on a portal dosimeter is applied to the patient's CT scans. Instead of making dose comparisons in a plane, Dosimetry Check system produces isodose lines and dose-volume histograms based on the planning CT images. By exporting the dose distribution from the treatment planning system into the Dosimetry Check system, one is able to make a direct comparison between the calculated dose and the planned dose. The versatility of the software is evaluated with respect to the two IMRT techniques - step and shoot and volumetric arc therapy. The system analyzed measurements made using EPID, PTW seven29, and IBA MatriXX, and an intercomparison study was performed. Plans from patients previously treated at our institution with treated anatomical site on brain, head & neck, liver, lung, and prostate were analyzed using Dosimetry Check system for any anatomical site dependence. We have recommendations and possible precautions that may be necessary to ensure proper QA with the Dosimetry Check system.

ACR Appropriateness Criteria: Localized nodal indolent lymphoma.

The present guidelines review epidemiology, pathology, presentation, workup, staging, prognostic factors, and treatment options for patients with localized nodal indolent lymphoma, with an emphasis on radiation guidelines, including radiation dose, field design, and radiation techniques. Following a discussion of the current literature and available data for treatment and outcomes of patients with indolent lymphoma, several different example cases are reviewed to help physicians make appropriate treatment decisions. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) by which the panel rates the appropriateness of imaging and treatment procedures. In those instances where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

The cost of elective nodal coverage in prostate cancer: Late quality of life outcomes and dosimetric analysis with 0, 45 or 54 Gy to the pelvis.

Purpose: Elective pelvic lymph node radiotherapy (PLNRT) in prostate cancer is often omitted from definitive (n = 267) and post prostatectomy (n = 160) radiotherapy (RT) due to concerns regarding toxicity and efficacy. Data comparing patient-reported outcome measures (PROMs) with or without PLNRT is limited. Our long-term supposition is that PLNRT, particularly to higher doses afforded by IMRT, will decrease pelvic failure rate in select patients. We aim to establish the impact of two different PLNRT doses on long term quality of life (QOL). Methods and materials: Prostate cancer patients (n = 428) recorded baseline scores using the Expanded Prostate Cancer Index Composite (EPIC), prior to definitive or post-prostatectomy RT. PLNRT, if given, was prescribed to 45 or 54 Gy at 1.8 Gy per fraction. New EPIC scores were recorded 20-36 months after radiotherapy. Absolute change in each domain subscale and summary score was recorded, along with if these changes met minimally important difference (MID) criteria. A separate multivariate analysis (MVA) was performed for each measure. Subsequent dosimetric analysis was performed. Results: Frequency of a MID decline was significantly greater with PLNRT to 54 Gy for urinary function, incontinence, and overall. No urinary decline was correlated with PLNRT to 45 Gy. PLNRT to 54 Gy was significant for decline in urinary function, bother, irritative, incontinence, and overall score in one or both MVA models while 45 Gy was not. Postoperative status was significant for decline in urinary function, incontinence, and overall. Amongst postoperative patients, there was significantly greater decline in urinary function score in the salvage setting. Neither 54 nor 45 Gy significantly affected bowel subscale or overall score decline. Conclusions: Using conventional fractionation, adding PLNRT to 54 Gy, but not 45 Gy, correlates with worse urinary QOL, with postoperative patients experiencing a steeper decline. PLNRT had no significant impact on bowel QOL with either dose.

Incidence of gastric involvement in patients with nongastrointestinal extranodal marginal zone lymphoma.

BACKGROUND: The current study was conducted to determine the incidence of gastric involvement in patients presenting with extranodal marginal zone lymphoma (MZL) outside the gastrointestinal (GI) tract and to identify clinical or laboratory parameters that predict gastric involvement in such cases. METHODS: The records of 121 consecutive patients who presented with non-GI extranodal MZL and had undergone esophagogastroduodenoscopy (EGD) as part of their initial workup were retrospectively reviewed. The authors assessed the presence of occult gastric MZL in these patients and possible associations with demographic characteristics; anatomic site of initial presentation; Helicobacter pylori (H. pylori) infection; Zubrod score; International Prognostic Index (IPI); B symptoms; and serum lactate dehydrogenase, hemoglobin, albumin, and ß2-microglobulin levels. RESULTS: The median age at diagnosis of non-GI MZL was 59 years. The most common primary tumor sites were the salivary/parotid gland (32 patients), ocular adnexa (26 patients), skin (19 patients), and lung (17 patients). Twenty-two patients (18%) were found to have gastric involvement on EGD. Using logistic regression analysis, factors found to be associated with gastric involvement included: high IPI score (odds ratio [OR], 3.70; P = .03), female sex (OR, 6.50; P = .02), serum ß2-microglobulin level of ≥ 2.5 mg/L (OR, 3.69; P = .02), and involvement of the aerodigestive mucosal/glandular tissue (OR, 4.50; P = .004). On multivariate logistic analysis, aerodigestive mucosal/glandular sites, H. pylori infection, and an elevated ß2-microglobulin level were found to be associated with gastric involvement. CONCLUSIONS: Routine EGD is recommended for patients with non-GI MZL, particularly those with primary aerodigestive mucosal/glandular tissue involvement or those with a high IPI, female sex, elevated serum ß2-microglobulin level, or H. pylori infection regardless of the primary tumor site.

Solitary plasmacytomas: outcome and prognostic factors after definitive radiation therapy.

BACKGROUND: The objective of this study was to review the outcome of patients with solitary plasmacytoma (SP) after definitive radiation therapy. METHODS: The authors retrospectively reviewed 84 patients with SP who were diagnosed and treated at The University of Texas MD Anderson Cancer Center during 1988 to 2008. The impact of tumor anatomic site, tumor size, and the presence of serum and urinary paraprotein at diagnosis was assessed on local control, survival, and the risk of developing multiple myeloma (MM). RESULTS: Fifty-nine patients (70%) had bone SP, and 25 patients (30%) had extramedullary SP. Serum paraprotein was present in 39 patients (46%). The median radiation dose was 45 grays (Gy) (range, 36-53.4 Gy). Local control was achieved in 77 patients (92%). Neither radiation dose nor tumor size predicted local control. The 5-year rate of progression to MM was 47% and was higher for patients with bone SP (56% vs 30% for extramedullary SP; P = .021), and patients who had serum paraprotein detected at diagnosis (60% vs 39%; P = .016). On univariate analysis, patients aged <60 years and men had higher rates of progression to MM, although the differences were not significant (P = .048 and P = .29, respectively). Multivariate analysis revealed that bone location and serum protein at diagnosis were associated statistically with progression to MM. The 5-year overall survival rate for the entire patient cohort was 78%, and no difference was observed between patients who had bone SP versus extramedullary SP (76% vs 85%, respectively; P = .274). CONCLUSIONS: The current results indicated that definitive radiation therapy for SP can provide excellent local control. Progression to MM remains the main problem and is more common among patients with bone SP and those who have serum paraprotein detected at diagnosis.

A Prospective Trial of Radiation Therapy Efficacy and Toxicity for Localized Mucosa-associated Lymphoid Tissue (MALT) Lymphoma.

PURPOSE: We report the long-term results of a prospective trial conducted to determine the efficacy and safety of radiation therapy (RT) alone in treating localized mucosa-associated lymphoid tissue (MALT) lymphoma. METHODS AND MATERIALS: Patients with localized MALT lymphoma were eligible and treated with involved field RT to doses of 24 to 39.6 Gy. Relapse-free survival (RFS) was the primary endpoint. Kaplan-Meier analysis was used to estimate RFS, progression-free survival (PFS), and overall survival (OS) defined from time of study entry. Preplanned subgroup analyses were performed based on site of involvement. RESULTS: From 2000 to 2012, 75 patients were accrued; 73 received protocol-specified RT. Median follow-up was 9.8 years. Thirty-four patients had gastric MALT, 17 orbital, 13 head and neck nonorbit, 4 skin, and 5 disease of other sites. Thirteen of 34 patients with gastric MALT were Helicobacter pylori positive at the time of initial diagnosis and underwent 1 to 3 courses of triple antibiotic therapy. All gastric MALT patients had documented persistent MALT without H. pylori on endoscopy before enrollment in the study. All patients achieved a complete response with a median time of 3 months. Eleven patients (15%) had disease relapse, 9 of which were at sites outside the RT field with median time to progression of 38.3 months. Median PFS was 17.5 years, and median RFS and OS were not reached. The 10-year relapse-free rate was 83% (95% confidence interval [CI], 74%-93%). The 10-year PFS rate was 71% (95% CI, 60%-84%). The 10-year OS rate was 86% (95% CI, 77%-96%). RFS, PFS, and OS did not differ by disease site (P = .17, .43, and .50, respectively). All relapses were successfully salvaged. One patient developed metastatic gastric adenocarcinoma and was found to also have recurrent MALT on biopsy. Otherwise, all relapsed patients were alive without evidence of disease at last follow-up, and no patient died of MALT lymphoma. Sixty-seven patients (92%) experienced acute toxicity during radiation, all of which were grade 1 and 2, with only 1 grade 3 toxicity. Twenty-two patients (30%) experienced late toxicity, with only 1 grade 3 toxicity. CONCLUSIONS: This prospective study confirms that RT for MALT lymphoma provides excellent long-term RFS with acceptable rates of toxicity. Current efforts are focused on RT de-escalation in an effort to further avoid treatment-related morbidity. CLINICALTRIALS.GOV: NCT04465162.

Primary Mediastinal B Cell Lymphoma in the Positron-Emission Tomography Era Executive Summary of the American Radium Society Appropriate Use Criteria.

PURPOSE: Primary mediastinal B cell lymphoma (PMBCL) is a highly curable subtype of non-Hodgkin lymphoma that is diagnosed predominantly in adolescents and young adults. Consequently, long-term treatment-related morbidity is critical to consider when devising treatment strategies that include different chemoimmunotherapy strategies with or without radiation therapy. Furthermore, adaptive approaches using the end-of-chemotherapy (EOC) positron emission tomography (PET)/computed tomography (CT) scanning may help to determine which patients may benefit from additional therapies. We aimed to develop evidence-based guidelines for treating these patients. METHODS AND MATERIALS: We conducted a systematic review in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guideline using the PubMed database. The ARS expert committee, composed of radiation oncologists, hematologists, and pediatric oncologists, developed consensus guidelines using the modified Delphi framework. RESULTS: Nine studies met the full criteria for inclusion based on reporting outcomes on patients with primary mediastinal B cell lymphoma with EOC PET/CT response scored with the 5-point Deauville scale. These studies formed the evidence for these guidelines in managing patients with PMBCL according to the EOC PET response, including after a 5-point Deauville scale of 1 to 3, 4, or 5, and for patients with relapsed and refractory disease. The expert group also developed guidance on radiation simulation, treatment planning, and plan evaluation based on expert opinion. CONCLUSIONS: Various treatment approaches exist in the management of PMBCL, including different chemoimmunotherapy regimens, the use of consolidative radiation therapy, and adaptive approaches based on EOC PET/CT response. These guidelines can be used by practitioners to provide appropriate treatment according to different disease scenarios.

Nodular lymphocyte predominant Hodgkin lymphoma: executive summary of the American radium society appropriate use criteria.

This guideline for nodular lymphocyte predominant Hodgkin lymphoma (NLPHL) by the American Radium Society was developed by a multidisciplinary expert panel of medical, pediatric, and radiation oncologists convened to formulate guidelines for evaluation and treatment. The guideline development was based on an in-depth literature review and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of the recommendations by the panel. Given the scarcity of compelling data for strong recommendations for a rare lymphoma that has been shown to be more indolent than classical Hodgkin lymphoma, in instances where evidence is not available or equivocal, expert opinion guided the recommendations. Four clinical variants exemplify common scenarios and represent the consensus recommendations for patients with nodular lymphocyte Hodgkin lymphoma. A summary of the available published literature is also presented.

Screening logs from a pilot randomized controlled trial of radical cystectomy versus chemoradiation therapy for muscle-invasive bladder cancer.

INTRODUCTION AND OBJECTIVES: There is growing interest in a bladder preservation approach using chemoradiation therapy with transurethral resection of bladder tumor (TURBT), i.e., combined modality treatment (CMT), for muscle-invasive bladder cancer (MIBC). We have initiated a pilot study to determine feasibility of conducting a larger-scale clinical trial comparing CMT to radical cystectomy (RC) in patients with MIBC. Here we present the screening logs from the recruitment phase of this trial. METHODS: Patients who were diagnosed to have MIBC after TURBT between April 2016 and August 2017 and considered to be candidates for surgery were enrolled in this prospective, single center, randomized controlled pilot feasibility trial and scheduled to undergo RC (with neoadjuvant chemotherapy if appropriate) or CMT. RESULTS: Of 62 patients screened during the recruitment phase, only 5 were found to be suitable candidates for either treatment modality hence eligible for randomization. The reasons for exclusion were as follows: multifocal disease (n = 24, 40%), variant histology (n = 15, 25%), previous pelvic radiation (n = 6, 10%), severe lower urinary tract symptoms (n = 5, 8.3%), unwillingness to be enrolled (n = 8, 13.3%), and receipt of neoadjuvant chemotherapy (n = 2, 3.3%). One of the 5 eligible patients was randomized to CMT but was subsequently switched to RC because of a high tumor burden, 1 was randomized to RC, 2 were randomized to CMT but subsequently underwent TURBT and were considered ineligible because of extensive bladder disease, and 1 elected to undergo RC. CONCLUSIONS: We identified many patients with MIBC over a period of 16 months. However, the number of patients eligible to receive chemotherapy and in whom cystectomy and radiation therapy were both valid options was not as high as previously reported in retrospective CMT series. Many patients were excluded after TURBT. Our preliminary data indicate that only a very small subset of patients with MIBC are ideal candidates for CMT. Further research is required to identify patients who are suitable for CMT.

Potential impact of consolidation radiation therapy for advanced Hodgkin lymphoma: a secondary analysis of SWOG S0816.

The role of radiotherapy (RT) in the management of advanced Hodgkin Lymphoma (HL) is inadequately defined in this era of functional imaging with PET scan. SWOG-S0816 treated advanced stage Hodgkin lymphoma patients with ABVD+/- escBEACOPP and no RT. We queried whether RT might have benefited patients in S0816 who would have met the GHSG-HD15 criteria for RT by simulating RT use as per HD15 criteria of PET + residual disease ≥2.5 cm. Receiver-operating-characteristics analyses were performed by varying disease-control rates within radiation fields and size cutoffs for residual disease. Among the 49 PET3+ S0816 patients, RT would have raised the 2-year PFS from 30.6% to 50.2-58.1% using three residual disease cutoffs (1.5, 2.0 and 2.5 cm) and assuming 80 and 90% in-field control rates . Although there may be improvement in PFS as size cutoff point is lowered, consequential toxicities from RT require further definition to assess relative benefits.

Clinical Outcomes of Spatially Fractionated GRID Radiotherapy in the Treatment of Bulky Tumors of the Head and Neck.

Objectives The clinical outcomes of patients treated with spatially fractionated GRID radiotherapy (SFGRT) for bulky tumors of the head and neck at a single institution were evaluated retrospectively. Endpoints of interest included tumor response, symptom improvement, treatment tolerance, and adverse events. Methods Institutional review board approval was obtained prior to study initiation. The institutional database was queried for patients with tumors of the head and neck treated with SFGRT between August 2007 and April 2015. Medical records of identified patients were reviewed for treatment details and clinical endpoints of interest. SFGRT was delivered in one fraction of 15 gray (Gy) or 20 Gy; 6 megavolt (MV) or 18 MV photon beams were passed through a multileaf collimator (MLC)-based or brass GRID template. All patients had a planned course of conventionally-fractionated external beam radiotherapy (EBRT) to begin on the day following SFGRT delivery. Results Twenty-one consecutive patients meeting study criteria were identified. The most common tumor histology was squamous cell carcinoma. Median patient age was 59 years (range 13 - 83 years); median maximum tumor dimension was 9.5 centimeters (cm) (range 5.0 - 25.0 cm). Fifteen patients (71.4%) completed their full course of EBRT. Twelve patients were treated with palliative intent for local tumor symptoms, of which 54.5% experienced some degree of symptom improvement. Of nine patients treated with curative intent, 44.4% achieved a clinical complete response (CR). Concurrent chemotherapy was administered in 12 patients, with all patients being treated having definitively received chemotherapy. Radiation Therapy Oncology Group (RTOG) grade three or higher skin toxicity occurred in five patients; no grade five events were reported. Conclusions Our institutional experience suggests that SFGRT is a feasible treatment option for the palliative or definitive management of large tumors of the head and neck. In combination with EBRT, SFGRT can provide timely symptom management and improve patient quality of life in the palliative setting. In the definitive setting, the addition of chemotherapy to SFGRT and EBRT can result in an excellent clinical response. Treatment toxicity was found to be within an acceptable range. When considering SFGRT for patients with these challenging presentations, careful patient selection is needed to identify those who will likely tolerate a full course of EBRT following SFGRT, as these patients are most likely to receive maximal benefit from SFGRT treatment. More data on the feasibility and efficacy of this radiation modality will be helpful for continued optimization of SFGRT delivery and patient selection.

Treatment and Outcomes of Primary Urethra Cancer.

BACKGROUND: Urethral cancer is a rare malignancy, representing <1% of all malignancies. Optimal management, due to its rarity, presents as a treatment dilemma for physicians. There is a lack of consensus regarding treatment as large randomized trials cannot be performed; thus, optimal management decisions rely on study of retrospective cases. This is a review of our institutional experience with urethral cancer treated with various treatment modalities. METHODS: A retrospective chart review was performed on 31 patients treated for primary cancer of the urethra from 1958 to 2008. The patients were stratified by sex, histologic type, stage, date of diagnosis, type of treatment, and last follow-up. Early stage cases were designated as Tis-T2N0M0 and advanced cases were designated as T3-4, N+ or M+. Analysis was performed based on clinical stage, treatment modalities and outcomes. RESULTS: Fourteen early stage cases and 17 advanced stage cases of urethral cancer were analyzed. The majority of early stage cases occurred in men (M:F=8:6) and the majority of advanced stage cases occurred in women (M:F=5:12). The most common histology was squamous cell carcinoma for both early and advanced stage cases. Surgery was the preferred modality of treatment for early stage cases (surgery used in 13 cases vs. chemo/radiotherapy used in 1 case) while for advanced cases, radiation ±chemotherapy was commonly used. Overall survival for this series was 45% at mean follow-up of 7 years. Eight of the 14 cases of early stage cancer remained disease free at last follow-up. Comparatively, only 5 of 17 with advanced cancers had no apparent disease at last follow-up. All but one of those patients were treated with combined modality therapy. CONCLUSIONS: Patients with early stage urethral cancers do well with single modality therapy, whereas patients who present with advanced cancers may benefit from combined modality therapy. More extensive study is required to recommend a particular treatment protocol. However, in this rare malignancy, institutional experiences provide the best evidence currently due to the lack of multi-institutional trials.

Report from the SWOG Radiation Oncology Committee: Research Objectives Workshop 2017.

The Radiation Therapy Committee of SWOG periodically evaluates its strategic plan in an effort to maintain a current and relevant scientific focus, and to provide a standard platform for future development of protocol concepts. Participants in the 2017 Strategic Planning Workshop included leaders in cancer basic sciences, molecular theragnostics, pharmaceutical and technology industries, clinical trial design, oncology practice, and statistical analysis. The committee discussed high-priority research areas, such as optimization of combined modality therapy, radiation oncology-specific drug design, identification of molecular profiles predictive of radiation-induced local or distant tumor responses, and methods for normal tissue-specific mitigation of radiation toxicity. The following concepts emerged as dominant questions ready for national testing: (i) what is the role of radiotherapy in the treatment of oligometastatic, oligorecurrent, and oligoprogressive disease? (ii) How can combined modality therapy be used to enhance systemic and local response? (iii) Can we validate and optimize liquid biopsy and other biomarkers (such as novel imaging) to supplement current response criteria to guide therapy and clinical trial design endpoints? (iv) How can we overcome deficiencies of randomized survival endpoint trials in an era of increasing molecular stratification factors? And (v) how can we mitigate treatment-related side effects and maximize quality of life in cancer survivors? The committee concluded that many aspects of these questions are ready for clinical evaluation and example protocol concepts are provided that could improve rates of cancer cure and quality of survival. Clin Cancer Res; 24(15); 3500-9. ©2018 AACR.

Fludarabine allows dose reduction for total body irradiation in pediatric hematopoietic stem cell transplantation.

PURPOSE: To examine, in the setting of total body irradiation (TBI) for the preparation of pediatric hematopoietic stem cell transplantation (HSCT), whether TBI dose can be reduced without compromising the efficacy of a regimen consisting of fludarabine and radiotherapy; and whether there is any increased risk of pulmonary toxicity due to the radiosensitizing effect of fludarabine. METHODS AND MATERIALS: A total of 52 pediatric patients with hematologic malignancies received TBI-based conditioning regimens in preparation for allogeneic HSCT. Twenty-three patients received 12 Gy in 4 daily fractions in combination with cyclophosphamide, either alone or with other chemotherapeutic and biologic agents. Twenty-nine patients received 9 Gy in 3 fractions in conjunction with fludarabine and melphalan. Clinical and radiation records were reviewed to determine engraftment, pulmonary toxicity (according to Radiation Therapy Oncology Group criteria), transplant-related mortality, recurrence of primary disease, and overall survival. RESULTS: The two groups of patients had comparable pretransplant clinical characteristics. For the 12-Gy and 9-Gy regimens, the engraftment (89% and 93%; p = 0.82), freedom from life-threatening pulmonary events (65% and 79%; p = 0.33), freedom from relapse (60% and 73%; p = 0.24), and overall survival (26% and 47%; p = 0.09) were not statistically different. CONCLUSIONS: The addition of fludarabine and melphalan seems to allow the dose of TBI to be lowered to 9 Gy without loss of engraftment or antitumor efficacy.