The Feasibility of Integrating Resting-State fMRI Networks into Radiotherapy Treatment Planning

BACKGROUND

Functional magnetic resonance imaging (fMRI) presents the ability to selectively protect functionally significant regions of the brain when primary brain tumors are treated with radiation therapy. Previous research has focused on task-based fMRI of language and sensory networks; however, there has been limited investigation on the inclusion of resting-state fMRI into the design of radiation treatment plans.

METHODS AND MATERIALS

In this pilot study of 9 patients with primary brain tumors, functional data from the default mode network (DMN), a network supporting cognitive functioning, was obtained from resting-state fMRI and retrospectively incorporated into the design of radiation treatment plans. We compared the dosimetry of these fMRI DMN avoidance treatment plans with standard of care treatment plans to demonstrate feasibility. In addition, we used normal tissue complication probability models to estimate the relative benefit of fMRI DMN avoidance treatment plans over standard of care treatment plans in potentially reducing memory loss, a surrogate for cognitive function.

RESULTS

On average, we achieved 20% (P = 0.002) and 12% (P = 0.002) reductions in the mean and maximum doses, respectively, to the DMN without compromising the dose coverage to the planning tumor volume or the dose-volume constraints to organs at risk. Normal tissue complication probability models revealed that when the fMRI DMN was considered during radiation treatment planning, the probability of developing memory loss was lowered by more than 20%.

CONCLUSION

In this pilot study, we demonstrated the feasibility of including rs-MRI data into the design of radiation treatment plans to spare cognitively relevant brain regions during radiation therapy. These results lay the groundwork for future clinical trials that incorporate such treatment planning methods to investigate the long-term behavioral impact of this reduction in dose to the cognitive areas and their neural networks that support cognitive performance.

Surgical resection for recurrent retroperitoneal leiomyosarcoma and liposarcoma

BACKGROUND

Retroperitoneal soft tissue sarcomas (STS) include a number of histologies but are rare, with approximately 3000 cases in the USA per year. Retroperitoneal STS have a high incidence of local and distant recurrence. The purpose of this study was to review the University of Maryland Medical Center's (UMMC) treatment experience of retroperitoneal STS, where the patient population served represents a diverse socioeconomic and ethnic catchment.

METHODS

IRB approval was obtained. We constructed a de-identified database of patients diagnosed with retroperitoneal liposarcomas (LPS) or leiomyosarcomas (LMS) treated at UMMC between 2000 and 2013. A total of 49 patients (Pts) with retroperitoneal STS met our eligibility criteria. Kaplan-Meier plots were used to graphically portray progression-free survival (PFS) and overall survival (OS). The log-rank test was used to compare time-to-event distributions.

RESULTS

The median OS for all patients (Pts) was 6.3 years, and the 2-year OS rate was 81%. The median PFS for all Pts was 1.8 years, and the 2-year PFS rate was 45%. There was no difference in OS and PFS among LMS and LPS patients; the median OS for LMS was 3.8 years vs. LPS 6.4 years (p = 0.33), and the median PFS for LMS was 1.2 years vs. LPS 2.5 years (p = 0.28). There was a significant difference between histology and race (p = 0.001). LPS were primarily Caucasian 86% vs. 14% black, whereas LMS were primarily black 52% vs. 33% Caucasian. OS was influenced by functional status, gender, American Joint Committee on Cancer (AJCC) stage, grade, histology, tumor size, and extent of resection. PFS was influenced by AJCC stage, grade, and extent of resection. Neither adjuvant chemotherapy (1 Pt) nor neoadjuvant/adjuvant radiation therapy (18 Pts) influenced OS or PFS. There was a non-significant difference that Pts who could undergo resection of local recurrence had improved 2-year OS, with 100% LMS and LPS compared to 2-year OS of 71% (LMS) and 78% (LPS) not undergoing resection of local recurrence.

CONCLUSIONS

This study suggests a higher incidence of leiomyosarcoma in the African-American population. This study confirms the prognostic importance of grade, tumor size, AJCC stage, histology, and extent of resection in patient outcomes, at a large substantially diverse academic medical center. Future research into the biological features of liposarcoma and leiomyosarcoma Pts imparting these characteristics will be important to define.

Prognostic Impact of Presurgical CA19-9 Level in Pancreatic Adenocarcinoma: A Pooled Analysis

BACKGROUND: Presurgical carbohydrate antigen 19-9 (CA19-9) level predicts overall survival (OS) in resected pancreatic adenocarcinoma (PaC). The aim of this pooled analysis was to evaluate if presurgical CA19-9 level can also predict local control (LC) and distant metastasis-free survival (DMFS). METHODS: Seven hundred patients with PaC from eight institutions who underwent surgical resection ± adjuvant treatment between 2000 and 2014 were analyzed. Patients were divided based on four presurgical CA19-9 level cutoffs (5, 37, 100, 353 U/ml). Weibull regression model to identify independent predictors of OS on 404 patients with complete information was fitted. RESULTS: Median follow-up was 17 months (range: 2-225 months). Univariate analysis showed a better prognosis in pT1-2, pN0, diameter <30 mm, or grade 1 tumors and in patients undergoing R0 resection, distal pancreatectomy, or adjuvant chemotherapy and with lower CA19-9 levels. Five-year OS, LC, and DMFS were as follows: CA19-9 <5.0: 5.7%, 47.2%, 17.0%; CA19-9 5.1-37.0: 37.9%, 63.3%, 46.0%; CA19-9 37.1-100.0: 27.1%, 59.4%, 39.0%; CA19-9 100.1-353.0: 17.4%, 43.4%, 26.7%; CA19-9 >353.1: 10.9%, 50.2%, and 23.4%, respectively. At multivariate analysis, CA19-9 >100 and <353 level (P=.002), CA19-9 ≥353.1 (P<.001) level, G3 tumor (P=.002), and tumor diameter >30 mm (P<.001) correlated with worse OS. Patients treated with postoperative chemoradiation doses >50.0 Gy showed improved OS (P<.001). CONCLUSION: Presurgical CA19-9 predicts both OS and pattern of failure. Therefore, CA19-9 should be included in predictive models in order to customize treatments based on prognostic factors. Moreover, future studies should stratify patients according to presurgical CA19-9 level.

Postresection CA19-9 and margin status as predictors of recurrence after adjuvant treatment for pancreatic carcinoma: Analysis of NRG oncology RTOG trial 9704

Purpose

NRG Oncology RTOG 9704 was the first adjuvant trial to validate the prognostic value of postresection CA19-9 levels for survival in patients with pancreatic carcinoma. The data resulting from this study also provide information about predictors of recurrence that may be used to tailor individualized management in this disease setting. This secondary analysis assessed the prognostic value of postresection CA19-9 and surgical margin status (SMS) in predicting patterns of disease recurrence.

Methods and materials

This multicenter cooperative trial included participants who were enrolled as patients at oncology treatment sites in the United States and Canada. The study included 451 patients analyzable for SMS, of whom 385 were eligible for postresection CA19-9 analysis. Postresection CA19-9 was analyzed at cut points of 90, 180, and continuously. Patterns of disease recurrence included local/regional recurrence (LRR) and distant failure (DF). Multivariable analyses included treatment, tumor size, and nodal status. To adjust for multiple comparisons, a P value of ≤ .01 was considered statistically significant and > .01 to ≤ .05 to be a trend.

Results

For CA19-9, 132 (34%) patients were Lewis antigen-negative (no CA19-9 expression), 200 (52%) had levels <90, and 220 (57%) had levels <180. A total of 188 patients (42%) had negative margins, 152 (34%) positive, and 111 (25%) unknown. On univariate analysis, CA19-9 cut at 90 was associated with increases in LRR (trend) and DF. Results were similar at the 180 cut point. SMS was not associated with an increase in LRR on univariate or multivariate analyses. On multivariable analysis, CA19-9 ≥ 90 was associated with increased LRR and DF. Results were similar at the 180 cut point.

Conclusions

In this prospective evaluation, postresection CA19-9 was a significant predictor of both LRR and DF, whereas SMS was not. These findings support consideration of adjuvant radiation therapy dose intensification in patients with elevated postresection CA19-9.

Expression of the DNA repair gene MLH1 correlates with survival in patients who have resected pancreatic cancer and have received adjuvant chemoradiation: NRG Oncology RTOG Study 9704

BACKGROUND

The majority of patients with pancreatic cancer who undergo curative resection experience rapid disease recurrence. In previous small studies, high expression of the mismatch-repair protein mutL protein homolog 1 (MLH1) in pancreatic cancers was associated with better outcomes. The objective of this study was to validate the association between MLH1 expression and survival in patients who underwent resection of pancreatic cancer and received adjuvant chemoradiation.

METHODS

Samples were obtained from the NRG Oncology Radiation Therapy Oncology Group 9704 prospective, randomized trial (clinicaltrials.gov identifier NCT00003216), which compared 2 adjuvant protocols in patients with pancreatic cancer who underwent resection. Tissue microarrays were prepared from formalin-fixed, paraffin-embedded, resected tumor tissues. MLH1 expression was quantified using fluorescence immunohistochemistry and automated quantitative analysis, and expression was dichotomized above and below the median value.

RESULTS

Immunohistochemical staining was successfully performed on 117 patients for MLH1 (60 and 57 patients from the 2 arms). The characteristics of the participants who had tissue samples available were similar to those of the trial population as a whole. At the time of analysis, 84% of participants had died, with a median survival of 17 months. Elevated MLH1 expression levels in tumor nuclei were significantly correlated with longer disease-free and overall survival in each arm individually and in both arms combined. Two-year overall survival was 16% in patients who had low MLH1 expression levels and 53% in those who had high MLH1 expression levels (P < .0001 for both arms combined). This association remained true on a multivariate analysis that allowed for lymph node status (hazard ratio, 0.41; 95% confidence interval, 0.27-0.63; P < .0001).

CONCLUSIONS

In the current sample, MLH1 expression was correlated with long-term survival. Further studies should assess whether MLH1 expression predicts which patients with localized pancreatic cancer may benefit most from aggressive, multimodality treatment. Cancer 2018;124:491-8. © 2017 American Cancer Society.

Stereotactic Radiosurgery for Treatment of Brain Metastases

Brain metastases are the most common intracranial malignancy. Incidence of brain metastases has risen as systemic therapies have improved and patients with metastatic disease live longer. Whole-brain radiation therapy, for many years, has been the standard treatment approach. Stereotactic radiosurgery has become an increasingly popular option because of its relatively short, convenient, and noninvasive treatment course. Although recently published data have renewed interest in use of whole-brain radiation therapy or systemic therapies for control of micrometastatic disease, stereotactic radiosurgery continues to be an important modality, capable of delivering ablative doses of radiation for long-term control of macroscopic disease. The purpose of this review is to explore the different paradigms for incorporation of stereotactic radiosurgery into management of brain metastases. Current uses for stereotactic radiosurgery include delivery as a boost with whole-brain radiation therapy; alone for patients with a limited number of brain metastases; in pre- or postoperative settings; and in combination with systemic, targeted, and immune-based therapies. Mature prospective data on use of stereotactic radiosurgery in combination with whole-brain radiation therapy is available; however, prospective, randomized data on stereotactic radiosurgery for patients with a greater number of brain metastases, its use in pre- and postoperative settings, and its use in combination with systemic therapies are limited. Data from ongoing and future studies are needed to define the appropriate use of stereotactic radiosurgery in these settings.

Does lymphocyte-to-monocyte ratio before, during, or after definitive chemoradiation for locally advanced pancreatic cancer predict for clinical outcomes?

BACKGROUND

Elevated pre-treatment lymphocyte (L) to monocyte (M) ratio (LMR) in peripheral blood has been suggested to correlate with improved survival in some malignancies, but data in the context of pancreatic cancer (PC) is limited. The aim of this study was to evaluate the prognostic significance of LMR before, during and after definitive chemoradiotherapy (CRT) for locally advanced pancreatic cancer (LAPC).

METHODS

We retrospectively reviewed 57 patients with LAPC treated with definitive CRT at a single institution from 2005 to 2013. Complete blood counts were obtained before (TP1), during the third week (TP2) and at the end of CRT (TP3). Univariate analysis (UVA) included gender, age, body mass index, pre-treatment CA19-9, T stage, N stage, induction chemotherapy (ICT), absolute L count (TP1, TP2, TP3), absolute M count (TP1, TP2, TP3), LMR (TP1, TP2, TP3), and relative LMR changes (TP2 ÷ TP1, TP3 ÷ TP1, TP3 ÷ TP2).

RESULTS

Median follow-up was 14 months. Twelve patients received ICT. Median LMR was 2.7 (range, 0.8-5.25), 1.4 (range, 0.3-5) and 0.98 (range, 0.3-3.4) at TP1, TP2 and TP3, respectively. Superior PFS was significantly associated with an absolute M count during CRT <0.1 (P=0.04) while pre-CRT L count ≥1.1 trended towards significance (P=0.09). Superior OS was significantly associated with change in LMR (TP3 ÷ TP2) > 0.32 (P<0.0001) while pre-CRT LMR ≥2.6 trended towards significance (P=0.06).

CONCLUSIONS

Factors significantly associated with overall survival (OS) and progression-free survival (PFS) were change in LMR at the end of CRT and absolute M count during CRT. This analysis suggests treatment-time-specific immune system parameters may affect clinical outcomes and warrant continued investigation.

Projected Improvements in Accelerated Partial Breast Irradiation Using a Novel Breast Stereotactic Radiotherapy Device: A Dosimetric Analysis

Accelerated partial breast irradiation has caused higher than expected rates of poor cosmesis. At our institution, a novel breast stereotactic radiotherapy device has demonstrated dosimetric distributions similar to those in brachytherapy. This study analyzed comparative dose distributions achieved with the device and intensity-modulated radiation therapy accelerated partial breast irradiation. Nine patients underwent computed tomography simulation in the prone position using device-specific immobilization on an institutional review board–approved protocol. Accelerated partial breast irradiation target volumes (planning target volume_10mm) were created per the National Surgical Adjuvant Breast and Bowel Project B-39 protocol. Additional breast stereotactic radiotherapy volumes using smaller margins (planning target volume_3mm) were created based on improved immobilization. Intensity-modulated radiation therapy and breast stereotactic radiotherapy accelerated partial breast irradiation plans were separately generated for appropriate volumes. Plans were evaluated based on established dosimetric surrogates of poor cosmetic outcomes. Wilcoxon rank sum tests were utilized to contrast volumes of critical structures receiving a percentage of total dose (Vx). The breast stereotactic radiotherapy device consistently reduced dose to all normal structures with equivalent target coverage. The ipsilateral breast V20-100 was significantly reduced (P < .05) using planning target volume_10mm, with substantial further reductions when targeting planning target volume_3mm. Doses to the chest wall, ipsilateral lung, and breast skin were also significantly lessened. The breast stereotactic radiotherapy device’s uniform dosimetric improvements over intensity-modulated accelerated partial breast irradiation in this series indicate a potential to improve outcomes. Clinical trials investigating this benefit have begun accrual.

Comparison of Onsite Versus Online Chart Reviews as Part of the American College of Radiation Oncology Accreditation Program

PURPOSE

Accreditation based on peer review of professional standards of care is essential in ensuring quality and safety in administration of radiation therapy. Traditionally, medical chart reviews have been performed by a physical onsite visit. The American College of Radiation Oncology Accreditation Program has remodeled its process whereby electronic charts are reviewed remotely.

METHODS

Twenty-eight radiation oncology practices undergoing accreditation had three charts per practice undergo both onsite and online review. Onsite review was performed by a single reviewer for each practice. Online review consisted of one or more disease site-specific reviewers for each practice. Onsite and online reviews were blinded and scored on a 100-point scale on the basis of 20 categories. A score of less than 75 was failing, and a score of 75 to 79 was marginal. Any failed charts underwent rereview by a disease site team leader.

RESULTS

Eighty-four charts underwent both onsite and online review. The mean scores were 86.0 and 86.9 points for charts reviewed onsite and online, respectively. Comparison of onsite and online reviews revealed no statistical difference in chart scores ( P = .43). Of charts reviewed, 21% had a marginal (n = 8) or failing (n = 10) score. There was no difference in failing charts ( P = .48) or combined marginal and failing charts ( P = .13) comparing onsite and online reviews.

CONCLUSION

The American College of Radiation Oncology accreditation process of online chart review results in comparable review scores and rate of failing scores compared with traditional on-site review. However, the modern online process holds less potential for bias by using multiple reviewers per practice and allows for greater oversight via disease site team leader rereview.

Individually optimized contrast-enhanced 4D-CT for radiotherapy simulation in pancreatic ductal adenocarcinoma

PURPOSE

To develop an individually optimized contrast-enhanced (CE) 4D-computed tomography (CT) for radiotherapy simulation in pancreatic ductal adenocarcinomas (PDA).

METHODS

Ten PDA patients were enrolled. Each underwent three CT scans: a 4D-CT immediately following a CE 3D-CT and an individually optimized CE 4D-CT using test injection. Three physicians contoured the tumor and pancreatic tissues. Image quality scores, tumor volume, motion, tumor-to-pancreas contrast, and contrast-to-noise ratio (CNR) were compared in the three CTs. Interobserver variations were also evaluated in contouring the tumor using simultaneous truth and performance level estimation.

RESULTS

Average image quality scores for CE 3D-CT and CE 4D-CT were comparable (4.0 and 3.8, respectively; P = 0.082), and both were significantly better than that for 4D-CT (2.6, P < 0.001). Tumor-to-pancreas contrast results were comparable in CE 3D-CT and CE 4D-CT (15.5 and 16.7 Hounsfield units (HU), respectively; P = 0.21), and the latter was significantly higher than in 4D-CT (9.2 HU, P = 0.001). Image noise in CE 3D-CT (12.5 HU) was significantly lower than in CE 4D-CT (22.1 HU, P = 0.013) and 4D-CT (19.4 HU, P = 0.009). CNRs were comparable in CE 3D-CT and CE 4D-CT (1.4 and 0.8, respectively; P = 0.42), and both were significantly better in 4D-CT (0.6, P = 0.008 and 0.014). Mean tumor volumes were significantly smaller in CE 3D-CT (29.8 cm³, P = 0.03) and CE 4D-CT (22.8 cm³, P = 0.01) than in 4D-CT (42.0 cm³). Mean tumor motion was comparable in 4D-CT and CE 4D-CT (7.2 and 6.2 mm, P = 0.17). Interobserver variations were comparable in CE 3D-CT and CE 4D-CT (Jaccard index 66.0% and 61.9%, respectively) and were worse for 4D-CT (55.6%) than CE 3D-CT.

CONCLUSIONS

CE 4D-CT demonstrated characteristics comparable to CE 3D-CT, with high potential for simultaneously delineating the tumor and quantifying tumor motion with a single scan.

Dosimetric Improvements with a Novel Breast Stereotactic Radiotherapy Device for Delivery of Preoperative Partial-Breast Irradiation

OBJECTIVE

Partial-breast irradiation (PBI) with external-beam radiotherapy has produced higher than expected rates of fair-to-poor cosmesis. Worsened outcomes have been correlated with larger volumes of breast tissue exposed to radiation. A novel breast-specific stereotactic radiotherapy (BSRT) device (BSRTD) has been developed at our institution and has shown promise in delivering highly conformal dose distributions. We compared normal tissue sparing with this device with that achieved with intensity-modulated radiation therapy (IMRT)-PBI.

METHODS

Fifteen women previously treated with breast conservation therapy were enrolled on an institutional review board-approved protocol. Each of them underwent CT simulation in the prone position using the BSRTD-specific immobilization system. Simulated postoperative and preoperative treatment volumes were generated based on surgical bed/clip position. Blinded planners generated IMRT-PBI plans and BSRT plans for each set of volumes. These plans were compared based on clinically validated markers for cosmetic outcome and toxicity using a Wilcoxon rank-sum test.

RESULTS

The BSRT plans consistently reduced the volumes receiving each of several dose levels (Vx) to breast tissue, the chest wall, the lung, the heart, and the skin in both preoperative and postoperative settings (p < 0.05). Preoperative BSRT yielded particularly dramatic improvements.

CONCLUSION

The novel BSRTD has demonstrated significant dosimetric benefits over IMRT-PBI. Further investigation is currently proceeding through initial clinical trials.

Preoperative Accelerated Partial Breast Irradiation for Early-Stage Breast Cancer: Preliminary Results of a Prospective, Phase 2 Trial

PURPOSE

To assess the feasibility of utilizing 3-dimensional conformal accelerated partial-breast irradiation (APBI) in the preoperative setting followed by standard breast-conserving therapy.

PATIENTS AND METHODS

This was a prospective trial testing the feasibility of preoperative APBI followed by lumpectomy for patients with early-stage invasive ductal breast cancer. Eligible patients had T1-T2 (<3 cm), N0 tumors. Patients received 38.5 Gy in 3.85-Gy fractions delivered twice daily. Surgery was performed >21 days after radiation therapy. Adjuvant therapy was given as per standard of care.

RESULTS

Twenty-seven patients completed treatment. With a median follow-up of 3.6 years (range, 0.5-5 years), there have been no local or regional failures. A complete pathologic response according to hematoxylin and eosin stains was seen in 4 patients (15%). There were 4 grade 3 seromas. Patient-reported cosmetic outcome was rated as good to excellent in 79% of patients after treatment.

CONCLUSIONS

Preoperative 3-dimensional conformal radiation therapy-APBI is feasible and well tolerated in select patients with early-stage breast cancer, with no reported local recurrences and good to excellent cosmetic results. The pathologic response rates associated with this nonablative APBI dose regimen are particularly encouraging and support further exploration of this paradigm.

Using low-dose radiation to potentiate the effect of induction chemotherapy in head and neck cancer: Results of a prospective phase 2 trial

Purpose

Low-dose fractionated radiation therapy (LDFRT) induces effective cell killing through hyperradiation sensitivity and potentiates effects of chemotherapy. We report our second investigation of LDFRT as a potentiator of the chemotherapeutic effect of induction carboplatin and paclitaxel in locally advanced squamous cell cancer of the head and neck (SCCHN).

Experimental design

Two cycles of induction therapy were given every 21 days: paclitaxel (75 mg/m²) on days 1, 8, and 15; carboplatin (area under the curve 6) day 1; and LDFRT 50 cGy fractions (2 each on days 1, 2, 8, and 15). Objectives included primary site complete response rate; secondary included overall survival, progression-free survival (PFS), disease-specific survival, and toxicity.

Results

A total of 24 evaluable patients were enrolled. Primary sites included oropharynx (62.5%), larynx (20.8%), oral cavity (8.3%), and hypopharynx (8.3%). Grade 3/4 toxicities included neutropenia (20%), leukopenia (32%), dehydration/hypotension (8%), anemia (4%), infection (4%), pulmonary/allergic rhinitis (4%), and diarrhea (4%). Primary site response rate was 23/24 (95.8%): 15/24 (62.5%) complete response, 8/24 (33.3%) partial response, and 1/24 (4.2%) stable disease. With median follow-up of 7.75 years, 9-year rates for overall survival were 49.4% (95% confidence interval [CI], 30.5-79.9), PFS was 72.2% (CI, 55.3-94.3), and disease-specific survival was 65.4% (44.3-96.4).

Conclusion

Chemopotentiating LDFRT combined with paclitaxel and carboplatin is effective in SCCHN and provided an excellent median overall survival of 107.2 months, with median PFS not yet reached in this locally advanced SCCHN cohort. This compares favorably to prior investigations and caused fewer grade 3 and 4 toxicities than more intensive, 3-drug induction regimens. This trial demonstrates the innovative use of LDFRT as a potentiator of chemotherapy.

Spatially Fractionated GRID Radiation Treatment of Advanced Neck Disease Associated with Head and Neck Cancer

Advanced nodal disease associated with head and neck cancer warrants aggressive, often multi-modality therapy to maximize local-regional control. The expansion of a novel treatment paradigm developed by our institution includes the addition of a single-fraction of high dose spatially-fractionated radiation (GRID) to a conventional course of treatment.

Between 1995 and 2002 a series of 27 patients (median age 65) with bulky N2-3 disease were treated. Median nodal tumor size was 7 cm. Two groups of patients were evaluated. Group 1 (N=14) patients received a median neck dose 69 Gy (range 54–79 Gy) plus GRID treatment. Group 2 (N=13) patients received a median neck dose of 59 Gy (range 54–72 Gy) plus GRID treatment followed by planned neck dissection. Patients were evaluated for local-regional control, pathological response, survival, and morbidity.

Median time to follow-up for Group 1 was 10 months (range 3–44 months). Neck control was 93%. Disease specific survival was 50%. Morbidity was limited to soft-tissue related damage and was mild. Median time to follow-up for Group 2 was 38 months (range 5–116 months). Pathologic complete response rate was 85%. Overall neck control rate was 92%. Disease specific survival was 85%. Surgical morbidity was limited to three wound healing complications.

GRID treatment may be safely added to conventional treatment management of locally advanced neck disease related to cancer with acceptable morbidity. It may improve pathologic complete response rates in those patients who undergo planned neck dissection, possibly leading to improved survival. In patients with inoperable bulky disease, addition of GRID enhances local-regional control.

Cancer Screening Patterns and Concerns in Caregivers of Patients Undergoing Radiation Therapy

PURPOSE

Evolving cancer screening guidelines can confuse the public. Caregivers of patients undergoing radiation oncology may represent a promising outreach target for disseminating and clarifying screening information. We aimed to: (1) determine the incidence of cancer screening in this cohort, and (2) identify barriers to and deficiencies in screening.

METHODS

We distributed a 21-item survey on cancer screening history and related concerns to caregivers ≥ 18 years old at one urban and two suburban radiation oncology centers. Reported screening habits were compared with American Cancer Society/American Urological Association guidelines for breast, cervical, colon, and prostate cancer. Statistical analysis included Pearson χ(2) tests.

RESULTS

A total of 209 caregivers (median age, 55.5 years; 146 women) were surveyed. Although 92% had primary care physicians (PCPs), only 58% reported being informed about recommended screening intervals. Participants ≤ 49 years old were less likely to report PCP discussion of cancer screening than older participants (41% and 66%, respectively; P = .006). Ninety-eight respondents (47%) had one or more screening concern(s). Among screening-eligible caregivers, 23 (18%) reported not undergoing regular colonoscopies. Fourteen women (13%) did not have Papanicolaou smears at recommended intervals, and 21 (18%) did not have annual mammograms. Six men (21%) did not undergo annual prostate screening. Decreased recommended screening with colonoscopy and mammography correlated with younger age.

CONCLUSION

This survey of relatively unexplored caregivers identified cancer screening deficiencies and concerns that might be addressed by targeted interventions. With approximately 60% of patients with cancer receiving radiation therapy, advice in the radiation oncology setting could positively affect cancer screening behaviors in caregivers.

RECQ1 A159C Polymorphism Is Associated With Overall Survival of Patients With Resected Pancreatic Cancer: A Replication Study in NRG Oncology Radiation Therapy Oncology Group 9704

PURPOSE

To confirm whether a previously observed association between RECQ1 A159C variant and clinical outcome of resectable pancreatic cancer patients treated with preoperative chemoradiation is reproducible in another patient population prospectively treated with postoperative chemoradiation.

METHODS AND MATERIALS

Patients were selected, according to tissue availability, from eligible patients with resected pancreatic cancer who were enrolled on the NRG Oncology Radiation Therapy Oncology Group 9704 trial of 5-fluorouacil (5-FU)-based chemoradiation preceded and followed by 5-FU or gemcitabine. Deoxyribonucleic acid was extracted from paraffin-embedded tissue sections, and genotype was determined using the Taqman method. The correlation between genotype and overall survival was analyzed using a Kaplan-Meier plot, log-rank test, and multivariate Cox proportional hazards models.

RESULTS

In the 154 of the study's 451 eligible patients with evaluable tissue, genotype distribution followed Hardy-Weinberg equilibrium (ie, 37% had genotype AA, 43% AC, and 20% CC). The RECQ1 variant AC/CC genotype carriers were associated with being node positive compared with the AA carrier (P=.03). The median survival times (95% confidence interval [CI]) for AA, AC, and CC carriers were 20.6 (16.3-26.1), 18.8 (14.2-21.6), and 14.2 (10.3-21.0) months, respectively. On multivariate analysis, patients with the AC/CC genotypes were associated with worse survival than patients with the AA genotype (hazard ratio [HR] 1.54, 95% CI 1.07-2.23, P=.022). This result seemed slightly stronger for patients on the 5-FU arm (n=82) (HR 1.64, 95% CI 0.99-2.70, P=.055) than for patients on the gemcitabine arm (n=72, HR 1.46, 95% CI 0.81-2.63, P=.21).

CONCLUSIONS

Results of this study suggest that the RECQ1 A159C genotype may be a prognostic or predictive factor for resectable pancreatic cancer patients who are treated with adjuvant 5-FU before and after 5-FU-based chemoradiation. Further study is needed in patients treated with gemcitabine to determine whether an association exists.

Glycogen Synthase Kinase 3 Beta Predicts Survival in Resected Adenocarcinoma of the Pancreas

PURPOSE

GSK3β is a protein kinase that can suppress a number of key oncoproteins. We have previously shown in preclinical models of pancreatic ductal adenocarcinoma (PDAC) that inhibition of GSK3β causes stabilization and nuclear translocation of β-catenin, poor differentiation, proliferation, and resistance to radiation. The objective of this study was to determine its utility as a biomarker of clinical outcomes.

EXPERIMENTAL DESIGN

Automated Quantitative Immunofluorescence Analysis (AQUA) of GSK3β was performed on a tissue microarray with samples from 163 patients treated on RTOG 9704. On the basis of findings in an exploratory cohort, GSK3β was analyzed as a categorical variable using its upper quartile (>Q3) as a cut point. Overall survival (OS) and disease-free survival (DFS) were estimated with the Kaplan-Meier method, and GSK3β groupings were compared using the log-rank test. Univariable and multivariable Cox proportional hazards models were used to determine associations between GSK3β and OS/DFS.

RESULTS

The 3-year OS rates for GSK3β≤Q3 versus GSK3β >Q3 were 16% (95% confidence intervals; CI, 10%-23%) and 30% (95% CI, 17%-44%), respectively, P = 0.0082. The 3-year DFS rates were 9% (95% CI, 5%-15%) and 20% (95% CI, 9%-33%) respectively, P value = 0.0081. On multivariable analysis, GSK3β was a significant predictor of OS. Patients with GSK3β >Q3 had a 46% reduced risk of dying of pancreatic cancer (HR, 0.54; 95% CI, 0.31-0.96, P value = 0.034). The HR for DFS was 0.65 (95% CI, 0.39-1.07; P value = 0.092).

CONCLUSIONS

GSK3β expression is a strong prognosticator in PDAC, independent of other known factors such as tumor (T) stage, nodal status, surgical margins and CA19-9. Clin Cancer Res; 21(24); 5612-8. ©2015 AACR.