The Society of Thoracic Surgeons/American Society for Radiation Oncology Updated Clinical Practice Guidelines on Multimodality Therapy for Locally Advanced Cancer of the Esophagus or Gastroesophageal Junction

Outcomes for patients with esophageal cancer have improved over the last decade with the implementation of multimodality therapy. There are currently no comprehensive guidelines addressing multidisciplinary management of esophageal cancer that have incorporated the input of surgeons, radiation oncologists, and medical oncologists. To address the need for multidisciplinary input in the management of esophageal cancer and to meet current best practices for clinical practice guidelines, the current guidelines were created as a collaboration between The Society of Thoracic Surgeons (STS), American Society for Radiation Oncology (ASTRO), and the American Society of Clinical Oncology (ASCO). Physician representatives chose 8 key clinical questions pertinent to the care of patients with locally advanced, resectable thoracic esophageal cancer (excluding cervical location). A comprehensive literature review was performed identifying 227 articles that met the inclusion criteria covering the use of induction chemotherapy, chemotherapy vs chemoradiotherapy before surgery, optimal radiation dose, the value of esophagectomy, timing of esophagectomy, the approach and extent of lymphadenectomy, the use of minimally invasive esophagectomy, and the value of adjuvant therapy after resection. The relevant data were reviewed and voted on by the panel with 80% of the authors, with 75% agreement on class and level of evidence. These data were then complied into the guidelines document.

The Society of Thoracic Surgeons/American Society for Radiation Oncology Updated Clinical Practice Guidelines on Multimodality Therapy for Locally Advanced Cancer of the Esophagus or Gastroesophageal Junction

Outcomes for patients with esophageal cancer have improved over the last decade with the implementation of multimodality therapy. There are currently no comprehensive guidelines addressing multidisciplinary management of esophageal cancer that have incorporated the input of surgeons, radiation oncologists, and medical oncologists. To address the need for multidisciplinary input in the management of esophageal cancer and to meet current best practices for clinical practice guidelines, the current guidelines were created as a collaboration between The Society of Thoracic Surgeons (STS), American Society for Radiation Oncology (ASTRO), and the American Society of Clinical Oncology (ASCO). Physician representatives chose 8 key clinical questions pertinent to the care of patients with locally advanced, resectable thoracic esophageal cancer (excluding cervical location). A comprehensive literature review was performed identifying 227 articles that met the inclusion criteria covering the use of induction chemotherapy, chemotherapy vs chemoradiotherapy before surgery, optimal radiation dose, the value of esophagectomy, timing of esophagectomy, the approach and extent of lymphadenectomy, the use of minimally invasive esophagectomy, and the value of adjuvant therapy after resection. The relevant data were reviewed and voted on by the panel with 80% of the authors, with 75% agreement on class and level of evidence. These data were then complied into the guidelines document.

NCI Rectal-Anal Task Force consensus recommendations for design of clinical trials in rectal cancer

The optimal management of locally advanced rectal cancer is rapidly evolving. The National Cancer Institute Rectal-Anal Task Force convened an expert panel to develop consensus on the design of future clinical trials of patients with rectal cancer. A series of 82 questions and subquestions, which addressed radiation and neoadjuvant therapy, patient perceptions, rectal cancer populations of special interest, and unique design elements, were subject to iterative review using a Delphi analytical approach to define areas of consensus and those in which consensus is not established. The task force achieved consensus on several areas, including the following: 1) the use of total neoadjuvant therapy with long-course radiation therapy either before or after chemotherapy, as well as short-course radiation therapy followed by chemotherapy, as the control arm of clinical trials; 2) the need for greater emphasis on patient involvement in treatment choices within the context of trial design; 3) efforts to identify those patients likely, or unlikely, to benefit from nonoperative management or minimally invasive surgery; 4) investigation of the utility of circulating tumor DNA measurements for tailoring treatment and surveillance; and 5) the need for identification of appropriate end points and recognition of challenges of data management for patients who enter nonoperative management trial arms. Substantial agreement was reached on priorities affecting the design of future clinical trials in patients with locally advanced rectal cancer.

An Analysis of Cancer Center-Provided Rideshare Utilization for Radiation Therapy

OBJECTIVES

The potential of rideshare services to facilitate timely radiation therapy (RT), especially for resource-limited patients, is understudied.

METHODS

Patients (n = 63) who received 73 courses of RT (1,513 fractions) and utilized free hospital-provided rideshare service (537 rides) were included in this retrospective study. A multidimensional analysis was conducted including a comparison of demographic, disease characteristics, and treatment completion data; a revenue analysis to evaluate the financial impact of rideshare services; and a geospatial analysis to evaluate community-level characteristics of patients.

RESULTS

Median age was 59; most were female (56%) and self-identified as Black or African American (56%), not working (91%), not partnered (83%), high school educated or less (78%), and insured with Medicaid (51%). Geospatial analysis revealed that patients lived in communities with significantly higher rates of resource deprivation. Median rideshare distance was 6.4 miles (interquartile range 3.4-11.2) with a median cost of $13.04 per rideshare (interquartile range 9-19). Of the rideshare-facilitated treatments, 100% were completed, with an overall course completion rate of 97.3% compared with 85.4% for those who did not use rideshare (P = .001); two patients discontinued RT for reasons unrelated to transportation. High rideshare utilization (n = 32), defined as utilization ≥ 45% of the treatment course, was associated with significantly shorter treatment courses and lower radiation doses compared with low rideshare utilization (P = .04). Total rideshare cost for high utilizers and whole cohort was $11,589 and $16,895, facilitating an estimated revenue of $401,952 and $1,175,119, respectively.

CONCLUSIONS

Free hospital-provided rideshare service is economically feasible and associated with high RT completion rates. It may help enhance quality radiation care for those who come from resource-limited communities.

Abdominopelvic MR to CT registration using a synthetic CT intermediate

Accurate coregistration of computed tomography (CT) and magnetic resonance (MR) imaging can provide clinically relevant and complementary information and can serve to facilitate multiple clinical tasks including surgical and radiation treatment planning, and generating a virtual Positron Emission Tomography (PET)/MR for the sites that do not have a PET/MR system available. Despite the long‐standing interest in multimodality co‐registration, a robust, routine clinical solution remains an unmet need. Part of the challenge may be the use of mutual information (MI) maximization and local phase difference (LPD) as similarity metrics, which have limited robustness, efficiency, and are difficult to optimize. Accordingly, we propose registering MR to CT by mapping the MR to a synthetic CT intermediate (sCT) and further using it in a sCT‐CT deformable image registration (DIR) that minimizes the sum of squared differences. The resultant deformation field of a sCT‐CT DIR is applied to the MRI to register it with the CT. Twenty‐five sets of abdominopelvic imaging data are used for evaluation. The proposed method is compared to standard MI‐ and LPD‐based methods, and the multimodality DIR provided by a state of the art, commercially available FDA‐cleared clinical software package. The results are compared using global similarity metrics, Modified Hausdorff Distance, and Dice Similarity Index on six structures. Further, four physicians visually assessed and scored registered images for their registration accuracy. As evident from both quantitative and qualitative evaluation, the proposed method achieved registration accuracy superior to LPD‐ and MI‐based methods and can refine the results of the commercial package DIR when using its results as a starting point. Supported by these, this manuscript concludes the proposed registration method is more robust, accurate, and efficient than the MI‐ and LPD‐based methods.

Combined multiagent chemotherapy and radiotherapy is associated with prolonged overall survival in patients with non-operatively managed stage II-III pancreatic adenocarcinoma

BACKGROUND

Most patients with pancreatic adenocarcinoma (PDAC) do not undergo surgical resection. The role of radiotherapy (RT) in non-operatively managed localized pancreatic adenocarcinoma is unclear.

METHODS

The National Cancer Database (2010-2016) was queried for patients with clinical stage II-III PDAC treated with multiagent systemic chemotherapy (CT) +/- RT but not surgery. Factors associated with the receipt of RT and overall survival were compared after adjusting for patient demographics and clinical characteristics.

RESULTS

A total of 14,921 patients were included, of whom 9279 received CT and 5382 received CT + RT. Patients treated with CT + RT were more likely to be younger (65vs66yrs), treated at non-academic facilities (48.8%vs46.7%), have private insurance (40.3%vs36.5%), and have clinical T4 tumors (53.6%vs48.7%). Most patients who were treated with RT received external beam radiotherapy (89.3%), and the median dose was 5,000 cGy. Median time to start of RT was 129 days. CT + RT was associated with longer overall survival (15.9vs11.8mos,p < 0.001), and remained associated with survival on multivariable analysis (HR 0.74, 95%CI 0.70-0.78). On a 4-month conditional survival analysis, combined CT + RT remained associated with improved survival compared to CT alone (16.0vs13.1mos,p < 0.001).

CONCLUSIONS

In patients with non-operatively managed localized pancreatic adenocarcinoma, combined radiotherapy and multiagent systemic chemotherapy is associated with improved overall survival compared to chemotherapy alone.

Repurposing Statin Drugs to Decrease Toxicity and Improve Survival Outcomes in Head and Neck Cancer

OBJECTIVE

The rising incidence of head and neck squamous cell carcinoma (HNSCC) calls for the assessment and improvement of currently available therapies that may enhance the therapeutic ratio in these patients. Statin drugs are one of the most widely used drug classes in the world for their lipid-lowering properties. As such, statins have been widely studied and found to possess pleiotropic effects that may make them effective in cancer treatment and toxicity mitigation. The aim of this review is to examine the potential use of statin drugs as adjunctive therapy in patients with HNSCC.

DATA SOURCES

PubMed.

REVIEW METHODS

Any preclinical or clinical articles pertaining to the effects of statin drugs on treatment-related toxicity or survival outcomes in patients with head and neck cancer were included in this narrative review.

CONCLUSIONS

Emerging data suggest that statins may improve survival and reduce toxicities associated with chemotherapy and radiotherapy in patients with head and neck cancer, by mechanisms that are poorly understood at present.

IMPLICATIONS FOR PRACTICE

Given their affordability and safety, statins deserve further study as a tool to improve oncologic outcomes and enhance survivorship in patients with HNSCC.

Neoadjuvant Radiotherapy is Associated With Improved Pathologic Outcomes and Survival in Resected Stage II-III Pancreatic Adenocarcinoma Treated With Multiagent Neoadjuvant Chemotherapy in the Modern Era

BACKGROUND

Neoadjuvant chemotherapy (CT) is being utilized more frequently in patients diagnosed with localized pancreatic cancer. The role of additional neoadjuvant radiotherapy (RT) remains undefined. We explored outcomes associated with neoadjuvant RT in the modern era.

METHODS

The National Cancer Database (2010-2017) was queried for patients with clinical stage II-III pancreatic adenocarcinoma who received neoadjuvant multiagent systemic CT +/- RT. Demographics, pathologic outcomes, postoperative outcomes, and overall survival were compared.

RESULTS

A total of 5245 patients were included, of whom 3123 received CT and 1941 received CT + RT. Use of RT decreased over the 8-year study period. On multivariable analysis, treatment at academic facilities (odds ratio (OR) = 1.52, P < .001) and clinical T4 tumors (OR = 1.68, P < .001) were independently associated with receipt of RT. Patients treated with CT + RT had a higher frequency of ypT0-T2 tumors (35.8% vs. 22.7%) and a lower rate of ypT3-T4 tumors (57.3% vs. 72.8%; P < .001), lower rate of node-positive disease (36.6% vs. 59.8%, P < .001), and margin-positive resections (13.8% vs. 20.2%, P < .001), but slightly higher 90-day postoperative mortality (4.9% vs. 3.6%, P = .04). Neoadjuvant chemotherapy+ RT was associated with longer overall survival (32.7 vs. 29.8 months, P = .008), and remained independently associated with survival on multivariable analysis (HR = .85, P < .001).

DISCUSSION

In patients with stage II-III pancreatic adenocarcinoma, the addition of neoadjuvant RT to multiagent neoadjuvant CT may be associated with increased rates of node-negative and margin-negative resection, as well as improved overall survival.

Possible Bioenergetic Biomarker for Chronic Cancer-Related Fatigue

BACKGROUND

Cancer-related fatigue is a highly prevalent, debilitating, and persistent symptom experienced by patients receiving cancer treatments. Up to 71% of men with prostate cancer receiving radiation therapy experience acute and persistent CRF. There is neither an effective therapy nor a diagnostic biomarker for cancer-related fatigue. This pilot study aimed to discover potential biomarkers associated with chronic cancer-related fatigue in men with prostate cancer receiving radiation therapy.

METHODS

We used a longitudinal repeated-measures research design. Twenty men with prostate cancer undergoing radiation therapy completed all study visits. Cancer-related fatigue was evaluated by a well-established and validated questionnaire, the Patient-Reported Outcomes Measurement Information System-Fatigue (PROMIS-F) Short Form. In addition, peripheral blood mononuclear cells (PBMC) were harvested to quantify ribonucleic acid (RNA) gene expression of mitochondria-related genes. Data were collected before, during, on completion, and 24 months postradiation therapy and analyzed using paired t-tests and repeated measures analysis of variance.

RESULTS

The mean of the PROMIS-F T-score was significantly increased over time in patients with prostate cancer, remaining elevated at 24 months post-radiation therapy compared to baseline. A significant downregulated BC1 ubiquinol-cytochrome c reductase synthesis-like (BCS1L) was observed over time during radiation therapy and at 24 months postradiation therapy. An increased PROMIS-F score was trended with downregulated BCS1L in patients 24 months after completing radiation therapy.

DISCUSSION

This is the first evidence to describe altered messenger RNA for BCS1L in chronic cancer-related fatigue using the PROMIS-F measure with men receiving radiation therapy for prostate cancer.

CONCLUSION

Our results suggest that PBMC messenger RNA for BCS1L is a potential biomarker and therapeutic target for radiation therapy-induced chronic cancer-related fatigue in this clinical population.

Nasopharyngeal neuroendocrine neoplasms: Systematic review of the literature and case presentation

Most of neuroendocrine neoplasms (NENs) are located in the gastrointestinal tract and lung, and they are rarely found on the upper aero-digestive tract, which limit the current literature about nasopharyngeal NENs. This systemic review will summarize the clinical, pathological features and optimal diagnosis and management of different types of nasopharyngeal NENs (NP NENs). In-addition, we herein report an EBV negative TP53-mutated/ Rb-wild type nasopharyngeal neuroendocrine carcinoma (NEC) in a young man in which touch preparation cytology studies were integral to establishing a definitive diagnosis. To our knowledge, only very few cases of primary neuroendocrine carcinoma of the nasopharynx have been reported in the literature and the reports of these cases have not included detailed description of different types and how to optimally diagnose and manage them. In this abstract, we also highlighted the evidence about the safety of using growth factors in patients with sickle cell anemia who are receiving cytotoxic chemotherapy.

Vocal-cord Only vs. Complete Laryngeal radiation (VOCAL): a randomized multicentric Bayesian phase II trial

BACKGROUND

Radiotherapy, along with laser surgery, is considered a standard treatment option for patients with early glottic squamous cell cancer (SCC). Historically, patients have received complete larynx radiotherapy (CL-RT) due to fear of swallowing and respiratory laryngeal motion and this remains the standard approach in many academic institutions. Local control (LC) rates with CL-RT have been excellent, however this treatment can carry significant toxicities include adverse voice and swallowing outcomes, along with increased long-term risk of cerebrovascular morbidity. A recent retrospective study reported improved voice quality and similar local control outcomes with focused vocal cord radiotherapy (VC-RT) compared to CL-RT. There is currently no prospective evidence on the safety of VC-RT. The primary objective of this Bayesian Phase II trial is to compare the LC of VC-RT to that of CL-RT in patients with T1N0 glottic SCC.

METHODS

One hundred and fifty-five patients with T1a-b N0 SCC of the true vocal cords that are n ot candidate or declined laser surgery, will be randomized in a 1:3 ratio the control arm (CL-RT) and the experimental arm (VC-RT). Randomisation will be stratified by tumor stage (T1a/T1b) and by site (each site will be allowed to select one preferred radiation dose regimen, to be used in both arms). CL-RT volumes will correspond to the conventional RT volumes, with the planning target volume extending from the top of thyroid cartilage lamina superiorly to the bottom of the cricoid inferiorly. VC-RT volumes will include the involved vocal cord(s) and a margin accounting for respiration and set-up uncertainty. The primary endpoint will be LC at 2-years, while secondary endpoints will include patient-reported outcomes (voice impairment, dysphagia and symptom burden), acute and late toxicity radiation-induced toxicity, overall survival, progression free survival, as well as an optional component of acoustic and objective measures of voice analysis using the Consensus Auditory-Perceptual Evaluation of Voice.

DISCUSSION

This study would constitute the first prospective evidence on the efficacy and safety of VC-RT in early glottic cancer. If positive, this study would result in the adoption of VC-RT as standard approach in early glottic cancer.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03759431 Registration date: November 30, 2018.

Radiation Therapy for Rectal Cancer: Executive Summary of an ASTRO Clinical Practice Guideline

PURPOSE

This guideline reviews the evidence and provides recommendations for the indications and appropriate technique and dose of neoadjuvant radiation therapy (RT) in the treatment of localized rectal cancer.

METHODS

The American Society for Radiation Oncology convened a task force to address 4 key questions focused on the use of RT in preoperative management of operable rectal cancer. These questions included the indications for neoadjuvant RT, identification of appropriate neoadjuvant regimens, indications for consideration of a nonoperative or local excision approach after chemoradiation, and appropriate treatment volumes and techniques. Recommendations were based on a systematic literature review and created using a predefined consensus-building methodology and system for grading evidence quality and recommendation strength.

RESULTS

Neoadjuvant RT is recommended for patients with stage II-III rectal cancer, with either conventional fractionation with concurrent 5-FU or capecitabine or short-course RT. RT should be performed preoperatively rather than postoperatively. Omission of preoperative RT is conditionally recommended in selected patients with lower risk of locoregional recurrence. Addition of chemotherapy before or after chemoradiation or after short-course RT is conditionally recommended. Nonoperative management is conditionally recommended if a clinical complete response is achieved after neoadjuvant treatment in selected patients. Inclusion of the rectum and mesorectal, presacral, internal iliac, and obturator nodes in the clinical treatment volume is recommended. In addition, inclusion of external iliac nodes is conditionally recommended in patients with tumors invading an anterior organ or structure, and inclusion of inguinal and external iliac nodes is conditionally recommended in patients with tumors involving the anal canal.

CONCLUSIONS

Based on currently published data, the American Society for Radiation Oncology task force has proposed evidence-based recommendations regarding the use of RT for rectal cancer. Future studies will look to further personalize treatment recommendations to optimize treatment outcomes and quality of life.

Adding Boost to Standard Neoadjuvant Radiation for Rectal Cancer Improves Likelihood of Complete Response

BACKGROUND

Pathologic tumor response is a prognostic factor for survival in patients with rectal cancer. Standard neoadjuvant radiation (nRT) dosing for locally advanced rectal cancer ranges from 4500 to 5400 centigray (cGy), but it is unknown if tumor regression differs as a consequence adding a boost to the tumor bed.

METHODS

The National Cancer Database (NCDB) 2006-2016 was used to identify patients 18 years of age and older with clinical stage II and III rectal cancer who received pelvic nRT dosed between 4500 and 5400 cGy. Standard nRT dose (no boost, NB) and dose with boost (DWB) were defined respectively as 4500 and 5040-5400 cGy. Complete pathologic response (pCR) was defined as postoperative pathologic stage of zero. A multivariate logistic regression was performed to evaluate the association between radiation dosing and pCR.

RESULTS

The study cohort was 28,841 patients; the majority received DWB 22,701 (78.7%), while 6140 (21.3%) received NB. pCR was achieved in 3135 (14.4%) patients. On multivariate analysis, patients who received NB were significantly less likely to have complete tumor response (OR 1.41, 95% CI 1.2-1.66, p < 0.001). Other factors significantly associated with pCR included insurance, facility type, tumor characteristics, clinical stage, and time between radiation and surgery.

CONCLUSIONS

This is the first investigation demonstrating that standard dose neoadjuvant radiation for rectal cancer was associated with a lower likelihood of pCR compared with standard dose with boost. Past studies demonstrate that rectal cancer patient survival is strongly correlated with pCR. Prospective trials should focus on examining neoadjuvant radiation dosing to evaluate if DWB improves outcomes.

Building Family Caregiver Skills Using a Simulation-Based Intervention: A Randomized Pilot Trial

OBJECTIVES

To evaluate the feasibility, acceptability, safety, and fidelity of a psychoeducational intervention to improve family caregiver technical and communication skills using structured simulations.

SAMPLE & SETTING

18 family caregivers of adult patients receiving radiation therapy for head and neck cancer at University Hospitals Seidman Cancer Center in Cleveland, Ohio.

METHODS & VARIABLES

A two-group, randomized pilot trial design was used. The intervention consisted of four one-on-one sessions between the caregiver and nurse interventionist during the patient's first, second, fourth, and sixth week of radiation treatment. Participants completed measures of self-efficacy for caregiving, anxiety, depression, and health-related quality of life at baseline, during the fifth week of radiation therapy, and four weeks after radiation therapy.

RESULTS

4 of the 9 caregiver participants completed the intervention. Improvements in scores for the intervention group were noted for self-efficacy, global mental health, anxiety, and depression.

IMPLICATIONS FOR NURSING

Refinement of the intervention is needed to improve feasibility. Although a caregiver intervention that incorporates simulation for skills training is acceptable and safe, flexibility in protocol is needed.

Delayed response to proton beam treatment of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) has become one of the leading causes of cancer death worldwide. There has been anecdotal report regarding the effectiveness of proton beam treatment for HCC. In this pre-clinical investigation, the woodchuck model of viral hepatitis infection-induced HCC was used for proton beam treatment experiment. The radiopaque fiducial markers that are biodegradable were injected around the tumor under ultrasound guidance to facilitate positioning in sequential treatments. An α cradle mode was used to ensure reproducibility of animal positioning on the treatment couch. A CT scan was performed first for contouring by a radiation oncologist. The CT data set with contours was then exported for dose planning. Three fractionations, each 750 CcGyE, were applied every other day with a Mevion S250 passive scattering proton therapy system. Multiphase contrast-enhanced CT scans were performed after the treatment and at later times for follow-ups. 3 weeks post-treatment, shrinking of the HCC nodule was detected and constituted to a partial response (30% reduction along the long axis). By week nine after treatment, the nodule disappeared during the arterial phase of multiphase contrast-enhanced CT scan. Pathological evaluation corroborated with this imaging response. A delayed, but complete imaging response to proton beam treatment applied to HCC was achieved with this unique and clinically relevant animal model of HCC.

Disparities in neoadjuvant radiation dosing for treatment of rectal cancer

BACKGROUND

Certain patients are less likely to undergo appropriate cancer treatment, worsening their overall cancer survival. The purpose of this investigation was to identify factors associated with inadequate neoadjuvant radiation for rectal cancer.

METHODS

The National Cancer Database was queried for patients with locally advanced rectal cancer who received neoadjuvant radiation 2006-2014. Adequate radiation was considered to be 4,500-5,040 cGy. Demographic, hospital and clinical variables were analyzed for association with inadequate radiation.

RESULTS

The study cohort was 34,391 patients; 1,842(5.4%) received inadequate radiation. On multivariate analysis, female gender, older age, other race, government-provided insurance, lower clinical stage and rural location correlated with inadequate radiation.

CONCLUSIONS

Women were 50% less likely than men to receive correct neoadjuvant radiation dosing. Other factors including age, race, insurance, clinical stage, geographic location and neoadjuvant chemotherapy were significantly associated with radiation dosing. These factors should be evaluated to determine if they can be modified to improve outcomes.

Development and Validation of a Small Animal Immobilizer and Positioning System for the Study of Delivery of Intracranial and Extracranial Radiotherapy Using the Gamma Knife System

The purpose of this research is to establish a process of irradiating mice using the Gamma Knife as a versatile system for small animal irradiation and to validate accurate intracranial and extracranial dose delivery using this system. A stereotactic immobilization device was developed for small animals for the Gamma Knife head frame allowing for isocentric dose delivery. Intercranial positional reproducibility of a reference point from a primary reference animal was verified on an additional mouse. Extracranial positional reproducibility of the mouse aorta was verified using 3 mice. Accurate dose delivery was validated using film and thermoluminescent dosimeter measurements with a solid water phantom. Gamma Knife plans were developed to irradiate intracranial and extracranial targets. Mice were irradiated validating successful targeted radiation dose delivery. Intramouse positional variability of the right mandible reference point across 10 micro-computed tomography scans was 0.65 ± 0.48 mm. Intermouse positional reproducibility across 2 mice at the same reference point was 0.76 ± 0.46 mm. The accuracy of dose delivery was 0.67 ± 0.29 mm and 1.01 ± 0.43 mm in the coronal and sagittal planes, respectively. The planned dose delivered to a mouse phantom was 2 Gy at the 50% isodose with a measured thermoluminescent dosimeter dose of 2.9 ± 0.3 Gy. The phosphorylated form of member X of histone family H2A (γH2AX) staining of irradiated mouse brain and mouse aorta demonstrated adjacent tissue sparing. In conclusion, our system for preclinical studies of small animal irradiation using the Gamma Knife is able to accurately deliver intracranial and extracranial targeted focal radiation allowing for preclinical experiments studying focal radiation.

The role of neoadjuvant therapy in pancreatic cancer: a review

Controversy remains regarding neoadjuvant approaches in the treatment of pancreatic cancer. Neoadjuvant therapy has several potential advantages over adjuvant therapy including earlier delivery of systemic treatment, in vivo assessment of response, increased resectability rate in borderline resectable patients and increased margin-negative resection rate. At present, there are no randomized data favoring neoadjuvant over adjuvant therapy and multiple neoadjuvant approaches are under investigation. Combination chemotherapy regimens including 5-fluorouracil, irinotecan and oxaliplatin, gemcitabine with or without abraxane, or docetaxel and capecitabine have been used in the neoadjuvant setting. Radiation and chemoradiation have also been incorporated into neoadjuvant strategies, and delivery of alternative fractionation regimens is being explored. This review provides an overview of neoadjuvant therapies for pancreatic cancer.