Factors Associated With Racial and Ethnic Disparities in Locally Advanced Rectal Cancer Outcomes

Importance

Hispanic and non-Hispanic Black patients receiving neoadjuvant therapy and surgery for locally advanced rectal cancer (LARC) achieve less favorable clinical outcomes than non-Hispanic White patients, but the source of this disparity is incompletely understood.

Objective

To assess whether racial and ethnic disparities in treatment outcomes among patients with LARC could be accounted for by social determinants of health and demographic, clinical, and pathologic factors known to be associated with treatment response.

Design, Setting, and Participants

The National Cancer Database was interrogated to identify patients with T3 to T4 or N1 to N2 LARC treated with neoadjuvant therapy and surgery. Patients were diagnosed between January 1, 2004, and December 31, 2017. Data were culled from the National Cancer Database from July 1, 2022, through December 31, 2023.

Exposure

Neoadjuvant therapy for rectal cancer followed by surgical resection.

Main Outcomes and Measures

The primary outcome was the rate of pathologic complete response (pCR) following neoadjuvant therapy. Secondary outcomes were rate of tumor downstaging and achievement of pN0 status.

Results

A total of 34 500 patient records were reviewed; 21 679 of the patients (62.8%) were men and 12 821 (37.2%) were women. The mean (SD) age at diagnosis was 59.7 (12.0) years. In terms of race and ethnicity, 2217 patients (6.4%) were Hispanic, 2843 (8.2%) were non-Hispanic Black, and 29 440 (85.3%) were non-Hispanic White. Hispanic patients achieved tumor downstaging (48.9% vs 51.8%; P = .01) and pN0 status (66.8% vs 68.8%; P = .02) less often than non-Hispanic White patients. Non-Hispanic Black race, but not Hispanic ethnicity, was associated with less tumor downstaging (odds ratio [OR], 0.86 [95% CI, 0.78-0.94]), less frequent pN0 status (OR, 0.91 [95% CI, 0.83-0.99]), and less frequent pCR (OR, 0.81 [95% CI, 0.72-0.92]). Other factors associated with reduced rate of pCR included rural location (OR, 0.80 [95% CI, 0.69-0.93]), lack of or inadequate insurance (OR for Medicaid, 0.86 [95% CI, 0.76-0.98]; OR for no insurance, 0.65 [95% CI, 0.54-0.78]), and treatment in a low-volume center (OR for first quartile, 0.73 [95% CI, 0.62-0.87]; OR for second quartile, 0.79 [95% CI, 0.70-0.90]; OR for third quartile, 0.86 [95% CI, 0.78-0.94]). Clinical and pathologic variables associated with a decreased pCR included higher tumor grade (OR, 0.58 [95% CI, 0.49-0.70]), advanced tumor stage (OR for T3, 0.56 [95% CI, 0.42-0.76]; OR for T4, 0.30 [95% CI, 0.22-0.42]), and lymph node-positive disease (OR for N1, 0.83 [95% CI, 0.77-0.89]; OR for N2, 0.73 [95% CI, 0.65-0.82]).

Conclusions and Relevance

The findings of this cohort study suggest that disparate treatment outcomes for Hispanic and non-Hispanic Black patients are likely multifactorial in origin. Future investigation into additional social determinants of health and biological variables is warranted.

Pulsed low-dose-rate radiation (PLDR) reduces the tumor-promoting responses induced by conventional chemoradiation in pancreatic cancer-associated fibroblasts

Pancreatic cancer is becoming increasingly deadly, with treatment options limited due to, among others, the complex tumor microenvironment (TME). This short communications study investigates pulsed low-dose-rate radiation (PLDR) as a potential alternative to conventional radiotherapy for pancreatic cancer neoadjuvant treatment. Our ex vivo research demonstrates that PLDR, in combination with chemotherapy, promotes a shift from tumor-promoting to tumor-suppressing properties in a key component of the pancreatic cancer microenvironment we called CAFu (cancer-associated fibroblasts and selfgenerated extracellular matrix functional units). This beneficial effect translates to reduced desmoplasia (fibrous tumor expansion) and suggests PLDR's potential to improve total neoadjuvant therapy effectiveness. To comprehensively assess this functional shift, we developed the HOST-Factor, a single score integrating multiple biomarkers. This tool provides a more accurate picture of CAFu function compared to individual biomarkers and could be valuable for guiding and monitoring future therapeutic strategies. Our findings support the ongoing NCT04452357 clinical trial testing PLDR safety and TME normalization potential in pancreatic cancer patients. The HOST-Factor will be used in samples collected from this trial to validate its potential as a key tool for personalized medicine in this aggressive disease.

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.

Source, co-occurrence, and prognostic value of PTEN mutations or loss in colorectal cancer

Somatic PTEN mutations are common and have driver function in some cancer types. However, in colorectal cancers (CRCs), somatic PTEN-inactivating mutations occur at a low frequency (~8-9%), and whether these mutations are actively selected and promote tumor aggressiveness has been controversial. Analysis of genomic data from ~53,000 CRCs indicates that hotspot mutation patterns in PTEN partially reflect DNA-dependent selection pressures, but also suggests a strong selection pressure based on protein function. In microsatellite stable (MSS) tumors, PTEN alterations co-occur with mutations activating BRAF or PI3K, or with TP53 deletions, but not in CRC with microsatellite instability (MSI). Unexpectedly, PTEN deletions are associated with poor survival in MSS CRC, whereas PTEN mutations are associated with improved survival in MSI CRC. These and other data suggest use of PTEN as a prognostic marker is valid in CRC, but such use must consider driver mutation landscape, tumor subtype, and category of PTEN alteration.

Prevalence and Predictors of Sexual Dysfunction (SD) after Treatment of Localized Rectal and Anal Cancer (LRAC)

PURPOSE/OBJECTIVE(S)

SD is possible after treatment of LRAC and is associated with distress and impaired quality of life. We report the prevalence of SD in our LRAC patients treated with curative intent. We also evaluate patient/treatment-related factors associated with SD.

MATERIALS/METHODS

LRAC patients from 2010-2022 were identified. Consented patients were surveyed and patient/treatment factors were collated from medical records. Sexual function (SF) was measured using the Female Sexual Function Index (FSFI) and the International Index of Erectile Function (IIEF). The impact of disease/treatment on SF since treatment was measured using the SF Questionnaire Medical Impact Scale (SFQ-MIS). FSFI ≤ 19.2 and IIEF ≤ 32.2 were considered SD based on the mean scores of SD patients in the primary literature. SFQ-MIS ≥ 15.5 was used to dichotomize responses into "at least some impact" versus "at least no impact." Spearman rank correlations examined correlations between FSFI/IIEF and factors. Comparisons involving componential domains and factors were based on a two-sided Mann-Whitney test. RT dose, surgery, the extent of lymphadenectomy, T stage, and time since treatment were factors assessed in all patients. In females, dilator use during RT, tumor distance (TD) from the anterior vaginal wall and whole vagina, and V25Gy, V45Gy, and mean dose to the anterior vaginal wall and whole vagina were other factors assessed. In males, TD from the neurovascular bundle (NVB), V25Gy, V45Gy, and mean dose to NVB was used.

RESULTS

Forty-five patients (13.5% response rate) completed study surveys (62% males; 80% white; 71% rectal cancer patients). The median age and time since treatment were 63 and 4 yrs. respectively. RT doses ranged from 25 - 54Gy. The overall prevalence of SD was 58% (71% in females; 50% in males). The proportion of patients who reported at least some SF impact was 56% (53% in females; 57% in males). There was a marginal association between higher total IIEF and receipt of surgery (p = 0.059). A correlation of 0.44 was seen between total IIEF and TD from upper NVB-the strongest among all comparisons. In the domains of IIEF, statistically significant associations were found between intercourse satisfaction (ISAT) and TD from upper NVB (p = 0.004), overall satisfaction (OSAT) and TD from lower NVB (p = 0.040), and ISAT and T stage (p = 0.047). There were marginal associations between TD from upper NVB and OSAT (p = 0.052), orgasm (p = 0.063), and erectile dysfunction (p = 0.097). There was a marginal association between V25Gy to the anterior vaginal wall and pain during penetrative sex (p = 0.095). No other association with FSFI or its domains was significant.

CONCLUSION

SD is prevalent in a large majority of patients studied (58%). In males, higher TD from NVB was associated with better overall SF, better intercourse, and overall satisfaction. While a higher proportion of females had SD, no significant associations were found in females likely due to their small sample size.

The Impact of Mutations of BRCA1/2 Genes in Patients with Breast Cancer on Treatment Outcomes Following Radiation Therapy (RT)

PURPOSE/OBJECTIVE(S)

BRCA1/2 mutations in isolated cancer cells have been shown to enhance radiosensitivity, but it is not known if similar mutations in breast cancer (BC) patients yield improved responses to RT. We analyzed a large, national, previously unexamined dataset to determine if patients with BRCA1/2 mutations receiving RT achieve longer disease-free survival (DFS) and overall survival (OS) than patients with wild-type (WT) BRCA genes.

MATERIALS/METHODS

The study used the nationwide Flatiron Health electronic health record (EHR)-derived de-identified database to select patients with Stage 0-III BC. Patients with known BRCA1/2 status were eligible if treated with RT≤ 1 year from diagnosis. Demographic data for patients with mutated and WT BRCA1/2 were compared using ANOVA and Chi-square tests. DFS was calculated from the start of RT until local/ distant recurrence or death and censored after the last clinic visit. Kaplan Meier estimates and multivariable Cox-proportional models (MVA) were used to compare DFS and OS for mutated and WT BRCA1/2 patients, for clinical stage, biomarkers (ER/PR/HER2), and surgery type (lumpectomy vs mastectomy).

RESULTS

The study group of 1561 Stage 0-III BC patients included 1482 patients (95%) with WT BRCA and 79 patients (5%) with BRCA1/2 mutations (31 patients with a mutation of BRCA1, 46 patients with a mutation of BRCA2, and 2 patients with both mutations). Patients with BRCA1/2 mutations were younger (median: 51 vs 56, p = 0.004), diagnosed at higher clinical stage (Stage 0: 0% vs 0.2%, I: 31.6% vs 48.5%, II: 48.1% vs 34.0%, III: 20.3 vs 17.4%, p = 0.016), and more often grade 3 (60.8% vs 39.9%, p<0.001) than those with WT BRCA. Mastectomy was performed more often for patients with BRCA1/2 mutations (60.8% vs 31.5%, p<0.001). When BRCA1 and BRCA2 mutations were compared, BRCA1 patients were younger (median: 44 vs 52, p = 0.006), more often ER/PR negative (51.6% vs 13%, p<0.001), and had higher stage tumors (T1: 32.3% vs 47.8%; T2: 38.7% vs 28.3%, p = 0.032). On MVA, comparison of BRCA1/2 mutations vs WT BRCA identified no differences in DFS or OS.

CONCLUSION

In spite of pre-clinical data demonstrating increased radiosensitivity for BRCA1/2-mutated BC cells lines, this large, previously unexamined dataset found BRCA1/2 mutations did not predict an improved OS or DFS for patients who received RT. When compared with WT BRCA patients, patients with BRCA1/2 mutations were found to have tumors of higher grade and clinical stage and to undergo more mastectomies. In a comparison with BRCA2-mutated patients, patients with mutations of BRCA1 were younger, more often ER/PR negative, and more likely to have high-stage tumors. The survival data and the advanced stage of BRCA1/2-mutated tumors suggest that the effect of BRCA1/2 mutations on radiosensitivity in vitro may be nullified by the aggressive behavior of BRCA1/2-mutated tumors in vivo.

Liver Fat and Its Association with Time to Biochemical Failure (TTBCF) after Definitive Treatment to the Prostate

PURPOSE/OBJECTIVE(S)

Elevated body mass index (BMI) is associated with an increased risk of biochemical failure (BCF); however, BMI may not best capture underlying health. We examined a different metric, liver fat, which may better approximate the body's metabolic state, to see its association with time to biochemical failure (TTBCF) in patients treated definitively for prostate cancer.

MATERIALS/METHODS

Of 210 patients who received a PSMA PET/CT at our institution, we identified 60 men treated with either prostatectomy or definitive radiation without androgen deprivation therapy who developed BCF. BCF was defined as PSA ≥ 0.2 ng/mL if treated with prostatectomy or PSA nadir + 2 ng/mL for those treated with definitive radiation. All prostatectomy patients had a post-op PSA < 0.1. Liver fat was evaluated via the non-contrast portion of respective PSMA PET/CT scans. Average Hounsfield Units (HU) of the liver were used to split individuals into high (≤ 56.1) and low (> 56.1) liver fat. A threshold of 56.1 HU was chosen as it corresponds to 5.56% liver fat, or the 95th percentile of non-obese, non-diabetic controls. Liver fat was quantified by converting HU to proton density fat fraction (PDFF) using the formula: PDFF = -0.582*HU + 38.214. Median TTBCF was estimated using Kaplan Meier methods, and Cox Proportional Hazards Regression was used for covariate adjustment.

RESULTS

Forty-four patients were classified as having high liver fat (HLF) and 16 as having low liver fat (LLF). Patients with HLF were more likely to have a higher BMI, have high risk disease, undergo surgery, and have shorter TTBCF (Table). When adjusted for NCCN risk category and treatment type, HLF was associated with twice the risk of BCF per unit time (aHR = 2.02, 95% CI [1.09 - 3.73], p = 0.03). With additional adjustment for BMI (continuous), HLF was no longer an independent predictor of TTBCF (aHR = 1.75, 95% CI [0.94 - 3.25], p = 0.08).

CONCLUSION

In this small study of patients who had biochemical failure after completing definitive treatment to the prostate, those with liver fat ≥ 5.56% were more likely to fail sooner, adjusting for risk category and treatment type. This project suggests that a man with elevated liver fat, on average, experiences a shorter interval free from prostate cancer.

Pre-Treatment Trends in Child-Pugh Score as an Indicator of Post-Treatment Survival in Patients Receiving Liver SBRT for HCC

PURPOSE/OBJECTIVE(S)

We sought to understand the value of Child-Pugh (CP) score trends prior to undergoing stereotactic body radiation therapy (SBRT) for hepatocellular carcinoma in patients with advanced cirrhosis, as an indicator of post-treatment morbidity and mortality. We hypothesize that an uptrend in CP score prior to RT increases risk of post-treatment cirrhosis progression, or death.

MATERIALS/METHODS

We retrospectively reviewed all patients who underwent definitive SBRT for HCC between 2014-2022 in our health system. Most patients were referred for treatment in the 2nd or 3rd line setting, allowing us to determine CP score at multiple points before SBRT. Response to treatment was evaluated with RECIST or mRECIST criteria. Acute treatment toxicities were assessed by CTCAE v5. OS was assessed using the Kaplan-Meier method, and differences between groups were evaluated using log-rank test.

RESULTS

A total of 61 patients were identified, 26 had an immediate pre-SBRT CP score of A5, 11 with A6, 10 with B7, 4 with B8, 4 with B9, 5 with C10, and 1 with C11. Median prescribed dose was 40Gy in 5fx. Median OS of all patients was 24 months. When stratified by CP category, median OS for CP A was not reached (NR) at time of analysis, CP B had a median OS of 14.8mo, and CP C with 1.9mo (p < 0.01). Local control rate at 6mo was 87.5%. 5 patients (8.3%) had CTCAE grade 2 acute toxicity. 10 patients had CP score progression of 2pts or more within 6mo after treatment, and 7 patients had a cause of death attributed to end stage liver disease. Median time interval between HCC diagnosis and start of RT was 338 days. In this time interval, patients with a CP score increase of 2 pts or more prior to starting RT had a median OS of 362 days, compared to NR for patients without increase (p = 0.02). When excluding the CP A group, patients with 2 pt increase had median OS of 362 days vs 445 days (p = 0.34). Again excluding the CP A group, patients with a 1 pt increase had median OS of 362 days vs NR (p = 0.23). Of 9 patients who had a pre-RT CP score increase of 2 pts or more, 7 experienced continued CP progression after treatment.

CONCLUSION

In this multi-institutional retrospective analysis, we found 24 patients with advanced CP B/C cirrhosis who underwent SBRT, none of whom received orthotopic liver transplant. While CP C patients did relatively poorly, we find that some patients with CP B cirrhosis may tolerate SBRT well with good oncologic effect. When taking pre-treatment CP score increase into consideration, we saw a trend but no statistical significance indicating that a pre-SBRT increase in CP score may be associated with worse OS after treatment among CP B/C patients. We conclude that there may be a subset of patients with advanced cirrhosis who, if well selected, are appropriate candidates for SBRT. We suggest a novel use of the CP score and pre-RT trends as an additional clinical tool to aid in decision making when selecting patients. We also suggest that patients with marked up-trending scores pre-treatment have a high likelihood of continued cirrhosis progression after treatment.

Understanding the Challenges Faced by Esophageal and Gastroesophageal Junction Cancer Survivors

The primary aim of this study is to characterize long-term quality of life (QOL) in patients with esophageal and gastroesophageal junction (EGEJ) cancers who underwent curative intent treatment. EGEJ survivors were recruited to participate in a one-time cross-sectional survey study using validated questionnaires assessing QOL. Chart review was conducted for patient demographics and clinical characteristics. Spearman correlation coefficients, Wilcoxon signed-rank test, and Fisher's exact test were used to assess relationships between patient characteristics and long-term outcomes. QOL was relatively high in this sample, as evidenced by high median scores on the functional scales and low median scores in the symptom domains of the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire (QLQ)-C30, with an overall median global health score of 75.0 (range 66.7-83.3). Patients using opiates at the time of survey reported lower role functioning (P  =  .004), social functioning (P  =  .052), and overall global health (P  =  .041). Younger patients had significantly higher rates of reflux (P  =  .019), odynophagia (P  =  .045), choking (P  =  .005), and cough (P  =  .007). Patients using opiates or of younger age had lower QOL and higher symptoms in this cohort of long-term EGEJ survivors.

Comparing Lifestyle Modifications and the Magnitude of Their Associated Benefit on Cancer Mortality

Many cancers are associated with poor diet, lack of physical activity, and excess weight. Improving any of these three lifestyle factors would likely reduce cancer deaths. However, modifications to each of these-better nutrition, enhanced activity and fitness, and loss of extra body fat-have different effect sizes on cancer mortality. This review will highlight the relative benefit that each lifestyle change, enacted prior to a diagnosis of cancer, might impart on cancer-related deaths, as well as attempt to quantify the changes required to derive such a benefit. The review relies primarily on epidemiological data, with meta-analyses serving as the backbone for comparisons across interventions and individual studies within the larger meta-analyses providing the data necessary to form more quantitative conclusions. The reader can then use this information to better understand, recommend, and implement behaviors that might ultimately reduce cancer mortality. Of all the interventions, it seems clear that exercise, specifically improving cardiorespiratory fitness, is the best way to decrease the risk of dying from cancer.

Association of Radiotherapy Duration With Clinical Outcomes in Patients With Esophageal Cancer Treated in NRG Oncology Trials: A Secondary Analysis of NRG Oncology Randomized Clinical Trials

Importance

For many types of epithelial malignant neoplasms that are treated with definitive radiotherapy (RT), treatment prolongation and interruptions have an adverse effect on outcomes.

Objective

To analyze the association between RT duration and outcomes in patients with esophageal cancer who were treated with definitive chemoradiotherapy (CRT).

Design, Setting, and Participants

This study was an unplanned, post hoc secondary analysis of 3 prospective, multi-institutional phase 3 randomized clinical trials (Radiation Therapy Oncology Group [RTOG] 8501, RTOG 9405, and RTOG 0436) of the National Cancer Institute-sponsored NRG Oncology (formerly the National Surgical Adjuvant Breast and Bowel Project, RTOG, and Gynecologic Oncology Group). Enrolled patients with nonmetastatic esophageal cancer underwent definitive CRT in the trials between 1986 and 2013, with follow-up occurring through 2014. Data analyses were conducted between March 2022 to February 2023.

Exposures

Treatment groups in the trials used standard-dose RT (50 Gy) and concurrent chemotherapy.

Main Outcomes and Measures

The outcomes were local-regional failure (LRF), distant failure, disease-free survival (DFS), and overall survival (OS). Multivariable models were used to examine the associations between these outcomes and both RT duration and interruptions. Radiotherapy duration was analyzed as a dichotomized variable using an X-Tile software to choose a cut point and its median value as a cut point, as well as a continuous variable.

Results

The analysis included 509 patients (median [IQR] age, 64 [57-70] years; 418 males [82%]; and 376 White individuals [74%]). The median (IQR) follow-up was 4.01 (2.93-4.92) years for surviving patients. The median cut point of RT duration was 39 days or less in 271 patients (53%) vs more than 39 days in 238 patients (47%), and the X-Tile software cut point was 45 days or less in 446 patients (88%) vs more than 45 days in 63 patients (12%). Radiotherapy interruptions occurred in 207 patients (41%). Female (vs male) sex and other (vs White) race and ethnicity were associated with longer RT duration and RT interruptions. In the multivariable models, RT duration longer than 45 days was associated with inferior DFS (hazard ratio [HR], 1.34; 95% CI, 1.01-1.77; P = .04). The HR for OS was 1.33, but the results were not statistically significant (95% CI, 0.99-1.77; P = .05). Radiotherapy duration longer than 39 days (vs ≤39 days) was associated with a higher risk of LRF (HR, 1.32; 95% CI, 1.06-1.65; P = .01). As a continuous variable, RT duration (per 1 week increase) was associated with DFS failure (HR, 1.14; 95% CI, 1.01-1.28; P = .03). The HR for LRF 1.13, but the result was not statistically significant (95% CI, 0.99-1.28; P = .07).

Conclusions and Relevance

Results of this study indicated that in patients with esophageal cancer receiving definitive CRT, prolonged RT duration was associated with inferior outcomes; female patients and those with other (vs White) race and ethnicity were more likely to have longer RT duration and experience RT interruptions. Radiotherapy interruptions should be minimized to optimize outcomes.

Disparate outcomes for Black patients following neoadjuvant chemoradiation for rectal cancer are multifactorial in origin

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Background: Studies have shown that Black patients receiving chemoradiation (CRT) for locally advanced rectal cancer (LARC) have achieved clinical outcomes less satisfactory than those achieved by other racial groups, but the source of this disparity is poorly understood. This study investigated the demographic, geographic, socioeconomic, and clinical factors that underlie this disparity. Methods: We interrogated the National Cancer Database from 2004-2017 to identify patients with T3-T4 or N > 0 LARC treated with CRT prior to surgery. Response to CRT was determined by the rates of pathologic complete response (pCR) and tumor downstaging after treatment. Univariate analysis (UVA) was performed with chi-square and Fisher’s exact tests. Multivariate analysis (MVA) was then used to identify independent factors associated with improved pCR. Results: A total of 37,783 patient records were reviewed for the study (7.8% Black, 86.0% White, 6.1% Other). Black patients were younger (p < 0.0001), more often female (p < 0.0001), and more likely to live in metropolitan areas (p < 0.0001). LARC in Black patients was diagnosed at a higher clinical stage (p = 0.0007) and was more often treated with abdominoperineal resection in preference to low anterior resection (p < 0.0001). Black patients were more often uninsured or covered by Medicaid (p < 0.0001) and less often covered by commercial insurance (p < .0001). UVA demonstrated that Black patients achieved pCR and tumor downstaging at lower rates than White patients (11.6% vs 14.5%; 46.9% vs 51.8%, both p < 0.0001). On MVA, Black race (OR 0.8015, 95%CI 0.7101-0.9047), a rural location (OR 0.8211, 95% CI 0.7082-0.952), absence of commercial medical insurance (Medicaid OR 0.8394 95% CI 0.7456-0.9449; Medicare OR 0.8989 95% CI 0.8226-0.9823; No Insurance OR 0.6107 95% CI 0.5103-0.7309), and higher tumor grade and stage remained independent risk factors for a lower pCR. Additional significant unfavorable prognostic factors for pCR included younger age, male sex, lower hospital treatment volume, and higher tumor grade or stage. Similarly, Black race, lower hospital treatment volume, absence of commercial medical insurance, and higher grade or stage were significant unfavorable prognostic factors for downstaging. Neither lower income nor fewer years of education was associated with pCR or tumor downstaging. Conclusions: The results confirm a lower rate of response to CRT in Black patients with LARC. The identification of race as an independent risk factor after adjustment for sociodemographic, geographic, and clinical factors suggests that other unknown variables–including genetic differences unaddressed in this study–must be pursued comprehensively in future studies. The more advanced stage of rectal cancers in Black patients suggests that critical evaluation of current cancer screening methods may play a role in this effort.

Use of the Toxicity Index in Evaluating Adverse Events in Anal Cancer Trials: Analysis of RTOG 9811 and RTOG 0529

Novel toxicity metrics that account for all adverse event (AE) grades and the frequency of may enhance toxicity reporting in clinical trials. The Toxicity Index (TI) accounts for all AE grades and frequencies for categories of interest. We evaluate the feasibility of using the TI methodology in 2 prospective anal cancer trials and to evaluate whether more conformal radiation (using Intensity Modulated Radiation Therapy) results in improved toxicity as measured by the TI. Patients enrolled on NRG/RTOG 0529 or nonconformal RT enrolled on the 5-Fluorouracil/Mitomycin arm of NRG/RTOG 9811 were compared using the TI. Patients treated on NRG/RTOG 0529 had lower median TI compared with patients treated with nonconformal RT on NRG/RTOG 9811 for combined GI/GU/Heme/Derm events (3.935 vs 3.996, P=0.014). The TI methodology is a feasible method to assess all AEs of interest and may be useful as a composite metric for future efforts aimed at treatment de-escalation or escalation.

[Teaching otorhinolaryngology in times of COVID-19: to what extent can digital formats replace face-to-face teaching?]

OBJECTIVE

Due to the coronavirus disease 19 (COVID-19) pandemic, postgraduate training in otorhinolaryngology in 2020 was transferred completely from face-to-face to digital teaching. This paper assesses whether this change was possible without a reduction in the quality of teaching and learning.

METHODS

Results of final written examinations were compared for the years 2016-2020, and the results of the teaching evaluation by the students for 2017-2020. The evaluation by students in 2020 included additional questions related to the switch from face-to-face to digital teaching. Additionally, the lecturers and teachers were asked for their assessments.

RESULTS

Results of the final written examination did not show any significant differences between 2016-2019 and 2020. Students were highly satisfied with the digital format, but values did not reach the level of former years with face-to-face-teaching. Especially the interaction with patients and the teaching of manual skills were rated lower in the digital format. Lecturers emphasized the additional workload for preparation of digital teaching.

CONCLUSION

The results of written examinations showed no difference between digital and face-to-face teaching. Online communication and interaction were reduced and regarded as cumbersome by students and faculty. Digital solutions providing more interaction and active participation are required. The digital format is more appropriate for teaching basic knowledge than for teaching practical skills.

The American Brachytherapy Society consensus statement for permanent implant brachytherapy using Yttrium-90 microsphere radioembolization for liver tumors

PURPOSE

To develop a multidisciplinary consensus for high quality multidisciplinary implementation of brachytherapy using Yttrium-90 (90Y) microspheres transarterial radioembolization (90Y TARE) for primary and metastatic cancers in the liver.

METHODS AND MATERIALS

Members of the American Brachytherapy Society (ABS) and colleagues with multidisciplinary expertise in liver tumor therapy formulated guidelines for 90Y TARE for unresectable primary liver malignancies and unresectable metastatic cancer to the liver. The consensus is provided on the most recent literature and clinical experience.

RESULTS

The ABS strongly recommends the use of 90Y microsphere brachytherapy for the definitive/palliative treatment of unresectable liver cancer when recommended by the multidisciplinary team. A quality management program must be implemented at the start of 90Y TARE program development and follow-up data should be tracked for efficacy and toxicity. Patient-specific dosimetry optimized for treatment intent is recommended when conducting 90Y TARE. Implementation in patients on systemic therapy should account for factors that may enhance treatment related toxicity without delaying treatment inappropriately. Further management and salvage therapy options including retreatment with 90Y TARE should be carefully considered.

CONCLUSIONS

ABS consensus for implementing a safe 90Y TARE program for liver cancer in the multidisciplinary setting is presented. It builds on previous guidelines to include recommendations for appropriate implementation based on current literature and practices in experienced centers. Practitioners and cooperative groups are encouraged to use this document as a guide to formulate their clinical practices and to adopt the most recent dose reporting policies that are critical for a unified outcome analysis of future effectiveness studies.

Real world use of radiation for newly diagnosed brain metastases in ALK-positive lung cancer receiving a first line ALK inhibitor

PURPOSE

Management paradigms now allow systemic targeted drugs before central nervous system (CNS)-directed radiotherapy (RT) in selected asymptomatic patients with non-small cell lung cancer (NSCLC) with brain metastases (BM). We aim to quantify how novel targeted agents with improved CNS activity, such as second-generation ALK inhibitors (e.g. alectinib), might impact the role of CNS-directed RT.

METHODS AND MATERIALS

This retrospective, observational, real world patterns of care study used a nationwide electronic health record-derived de-identified longitudinal database. A random sample of patients with ALK+ advanced NSCLC and BM on first-line ALK-inhibitor monotherapy between January 1, 2014 and August 31, 2019 were included. Using an index date of the first instance of BM, the outcome was brain-directed local treatment within four months. Trends over time were reported and tested using multivariable modified Poisson regression with robust error variance, including an indicator of in or after 2017 (when alectinib was approved).

RESULTS

Of 352 patients, 146 had BM. 104 received CNS-directed local therapy and 42 did not. The majority (89.4%) were treated with RT alone. Of those receiving RT, stereotactic radiosurgery (SRS) monotherapy was the most common (53%) followed by whole brain radiotherapy (WBRT) alone (39%). On multivariable analysis, those patients who had their first BM in or after 2017 had a decreased rate of receiving local BM treatment versus those prior to 2017 with an adjusted incidence rate ratio (aIRR) 0.63 (95% confidence interval [CI]: 0.41-0.95; p=0.026). We found no change in the proportion of BM treated with WBRT in or after 2017 vs before (aIRR = 0.70; 95% CI: 0.24-2.06; p = 0.517).

CONCLUSIONS

We found decreasing use of CNS-directed RT in patients with NSCLC with new BM on first-line ALK inhibitors. Clinical outcomes for these patients require continued investigation as physicians may be increasingly comfortable deferring upfront local therapy for BM in lieu of novel targeted agents with improved CNS activity.

A-43 Effects of Subthreshold Exercise on Post-concussive Symptom Endorsement and Cognition: A Pilot Randomized Clinical Trial

Purpose: The current study examined the effects of subthreshold exercise on symptom endorsement and neurocognitive functioning in adolescents with persisting concussion symptoms (&gt;1 month). Methods: Sixteen participants (age M = 16.2, SD = 1.4) with persisting concussion symptoms were randomly assigned to control or subthreshold exercise intervention groups (Leddy et al., 2019). Participants engaged in concussion education before assignment to 6 weeks (3x weekly) of intervention: control (stretching) or subthreshold exercise. Both groups completed evaluations at baseline, midpoint, and follow-up, including a hybrid battery of assessments (yielding composites of processing speed and memory), a concussion symptom scale (PCS-R), and psychological inventories. Results: Both the intervention group and control group reported significant reduction in concussive symptom severity during the study period (PCS-R Change M = -21.29, SD = 13.54). Baseline endorsement of anxiety significantly differed across groups (p &lt; 0.05); when controlling for anxiety, the intervention group demonstrated greater reduction in symptom endorsement compared to controls (F(1,13) = 7.30, p &lt; 0.05, partial eta2 = 0.40). In contrast, after controlling for performance validity and the baseline anxiety difference, there was no significant difference (p &gt; 0.05) in processing speed performance (partial eta2 = 0.14) or memory performance (partial eta2 = 0.11) by intervention group. Both groups remained generally intact normatively from the baseline to the follow-up evaluation across measures. Conclusions: Current results support the use of subthreshold exercise to reduce persisting symptoms of concussion post-acutely; additionally, results suggest that anxiety significantly impacted response to intervention. Lastly, there was no effect on cognitive indices by the intervention, suggesting that subthreshold exercise may have less impact on cognition than symptom endorsement in the post-acute phase of recovery.

Delineating The RAS Conformational Landscape

Mutations in RAS isoforms (KRAS, NRAS, and HRAS) are among the most frequent oncogenic alterations in many cancers, making these proteins high priority therapeutic targets. Effectively targeting RAS isoforms requires an exact understanding of their active, inactive, and druggable conformations. However, there is no structural catalog of RAS conformations to guide therapeutic targeting or examining the structural impact of RAS mutations. Here we present an expanded classification of RAS conformations based on analyses of the catalytic switch 1 (SW1) and switch 2 (SW2) loops. From 721 human KRAS, NRAS, and HRAS structures available in the Protein Data Bank (206 RAS-protein co-complexes, 190 inhibitor-bound, and 325 unbound, including 204 WT and 517 mutated structures), we created a broad conformational classification based on the spatial positions of Y32 in SW1 and Y71 in SW2. Clustering all well-modeled SW1 and SW2 loops using a density-based machine learning algorithm defined additional conformational subsets, some previously undescribed. Three SW1 conformations and nine SW2 conformations were identified, each associated with different nucleotide states (GTP-bound, nucleotide-free, and GDP-bound) and specific bound proteins or inhibitor sites. The GTP-bound SW1 conformation could be further subdivided based on the hydrogen bond type made between Y32 and the GTP γ-phosphate. Further analysis clarified the catalytic impact of G12D and G12V mutations and the inhibitor chemistries that bind to each druggable RAS conformation. Overall, this study has expanded our understanding of RAS structural biology, which could facilitate future RAS drug discovery.

Therapeutic implications of germline vulnerabilities in DNA repair for precision oncology

DNA repair vulnerabilities are present in a significant proportion of cancers. Specifically, germline alterations in DNA repair not only increase cancer risk but are associated with treatment response and clinical outcomes. The therapeutic landscape of cancer has rapidly evolved with the FDA approval of therapies that specifically target DNA repair vulnerabilities. The clinical success of synthetic lethality between BRCA deficiency and poly(ADP-ribose) polymerase (PARP) inhibition has been truly revolutionary. Defective mismatch repair has been validated as a predictor of response to immune checkpoint blockade associated with durable responses and long-term benefit in many cancer patients. Advances in next generation sequencing technologies and their decreasing cost have supported increased genetic profiling of tumors coupled with germline testing of cancer risk genes in patients. The clinical adoption of panel testing for germline assessment in high-risk individuals has generated a plethora of genetic data, particularly on DNA repair genes. Here, we highlight the therapeutic relevance of germline aberrations in DNA repair to identify patients eligible for precision treatments such as PARP inhibitors (PARPis), immune checkpoint blockade, chemotherapy, radiation therapy and combined treatment. We also discuss emerging mechanisms that regulate DNA repair.

Neoadjuvant Chemoradiation Impacts the Prognostic Effect of Surgical Margin Status in Pancreatic Adenocarcinoma

BACKGROUND

Many studies show significantly improved survival after R0 resection compared with R1 resection in pancreatic adenocarcinoma (PAC); however, the effect of neoadjuvant chemoradiation (NACRT) on this association is unknown.

OBJECTIVE

The aim of this study was to evaluate the prognostic significance of positive surgical margins (SMs) after NACRT compared with upfront surgery + adjuvant therapy in PAC.

METHODS

All cases of surgically resected PAC at a single institution were reviewed from 1996 to 2014; patients treated with palliative intent, metastatic disease, and biliary/ampullary tumors were excluded. The primary endpoint was overall survival (OS).

RESULTS

Overall, 300 patients were included; 134 patients received NACRT with concurrent 5-fluorouracil or gemcitabine followed by surgery, and 166 patients received upfront surgery (+ adjuvant chemotherapy in 72% of patients and RT in 65%); 31% of both groups had a positive SM (+SM). The median OS for patients with a +SM or negative SM (-SM) was 26.6 and 31.6 months, respectively for NACRT, and 12.0 and 24.5 months, respectively, for upfront surgery. OS was significantly improved with -SM compared with +SM in both groups (p = 0.006). When resection yielded +SM, NACRT patients had improved OS compared with upfront surgery patients (p < 0.001). On multivariable analysis, +SM in the upfront surgery group (hazard ratio [HR] 2.94, 95% confidence interval [CI] 2.04-4.24; p < 0.001) and older age (HR 1.01, 95% CI 1.00-1.03, per year; p = 0.007) predicted worse OS. +SM in the NACRT group was not associated with worse OS (HR 1.09, 95% CI 0.72-1.65; p = 0.70).

CONCLUSION

Patients with a positive margin after NACRT and surgery had longer survival compared with patients with a positive margin after upfront surgery. NACRT should be strongly considered for patients at high risk of R1 resections.

Feasibility of Fitness Tracker Usage to Assess Activity Level and Toxicities in Patients With Colorectal Cancer

PURPOSE

Performance status (PS) is a subjective assessment of patients' overall health. Quantification of physical activity using a wearable tracker (Fitbit Charge [FC]) may provide an objective measure of patient's overall PS and treatment tolerance.

MATERIALS AND METHODS

Patients with colorectal cancer were prospectively enrolled into two cohorts (medical and surgical) and asked to wear FC for 4 days at baseline (start of new chemotherapy [± 4 weeks] or prior to curative resection) and follow-up (4 weeks [± 2 weeks] after initial assessment in medical and postoperative discharge in surgical cohort). Primary end point was feasibility, defined as 75% of patients wearing FC for at least 12 hours/d, 3 of 4 assigned days. Mean steps per day (SPD) were correlated with toxicities of interest (postoperative complication or ≥ grade 3 toxicity). A cutoff of 5,000 SPD was selected to compare outcomes.

RESULTS

Eighty patients were accrued over 3 years with 55% males and a median age of 59.5 years. Feasibility end point was met with 68 patients (85%) wearing FC more than predefined duration and majority (91%) finding its use acceptable. The mean SPD count for patients with PS 0 was 6,313, and for those with PS 1, it was 2,925 (122 and 54 active minutes, respectively) (P = .0003). Occurrence of toxicity of interest was lower among patients with SPD > 5,000 (7 of 33, 21%) compared with those with SPD < 5,000 (14 of 43, 32%), although not significant (P = .31).

CONCLUSION

Assessment of physical activity with FC is feasible in patients with colorectal cancer and well-accepted. SPD may serve as an adjunct to PS assessment and a possible tool to help predict toxicities, regardless of type of therapy. Future studies incorporating FC can standardize patient assessment and help identify vulnerable population.

Initial Clinical Experience With Novel Directional Low-dose Rate Brachytherapy for Retroperitoneal Sarcoma

BACKGROUND

A novel Palladium-103 low-dose rate (LDR) brachytherapy device was developed to provide dose-escalation to the tumor bed after resection while shielding adjacent tissues. This multicenter report describes the initial experience with this device in patients with retroperitoneal sarcoma (RPS).

MATERIALS AND METHODS

Patients with recurrent RPS, prior radiotherapy, and/or concern for positive margins were considered. An LDR brachytherapy dose of 20-60 Gy was administered, corresponding to biologically effective dose values of 15-53 Gy and equivalent dose values of 12-43 Gy.

RESULTS

Six patients underwent implantation at four institutions. Of these, five had recurrent disease in the retroperitoneum or pelvic sidewall, one had untreated locally advanced leiomyosarcoma, two had prior external beam radiation therapy at the time of initial diagnosis, and four received neoadjuvant external beam radiation therapy plus brachytherapy. The device was easily implanted and conformed to the treatment area. Median follow-up was 16 mo; radiation was delivered to the at-risk margin with minimal irradiation of adjacent structures. No local recurrences at the site of implantation, device migration, or radiation-related toxicities were observed.

CONCLUSIONS

The novel LDR directional brachytherapy device successfully delivered a targeted dose escalation to treat RPS high-risk margins. Lack of radiation-related toxicity demonstrates its safety.

Abstract 349: Association of DNA damage response capacity with neoadjuvant chemoradiation response in locally advanced rectal cancer

Background: Locally advanced rectal cancer (RC) cases are ~60% of newly diagnosed RCs, with neoadjuvant chemoradiation therapy (nCRT) followed by surgery as the standard of care. While nCRT is highly toxic, it is also beneficial. Recent prospective trials reported that up to 59% locally advanced RC cases exhibit complete clinical response, suggesting these patients as ideal candidates for organ preservation. However, currently there is no biomarker to predict who will or will not benefit from nCRT. The goal of this study was to establish a predictive biomarker for benefit from nCRT, based on the hypothesis that inherent DNA damage response (DDR) capacity contributes to nCRT response in RC.

Methods: To gain insight into inherent DDR capacity, we profiled primary peripheral blood lymphocytes (pPBLs) from RC patients by quantitative immunofluorescence, Luminex-multianalyte assay, and pPBL DNA whole exome sequencing (WES). RC patients analyzed were segregated by neoadjuvant rectal (NAR) score: NAR&lt;1, complete responders (CRs), n=21; NAR&gt;14, poor responders (PoRs), n=21; 1&lt;NAR&lt;14, partial responders (PRs), n=12. Conditional inference trees were used to establish optimal cut points for the nCRT response outcomes data. Single nucleotide variants from WES data were annotated and analyzed for variation in genes involved in DDR, and associated pathways. The variants were annotated as predicted-pathogenic based on the consensus of four variant effect prediction programs.

Results: pPBLs from CRs showed significantly elevated γH2AX foci (a hallmark of double strand breaks) vs. PoRs (P&lt;0.001, Kruskal-Wallis test). Multianalyte DDR panel testing revealed significantly increased expression or activation of 6 DDR proteins (ATR, MDM2, phosphorylated H2AXS139 (γ), p53S15, Chk1S345, and Chk2T68) in pPBLs from CRs versus PoRs (p&lt;0.01, logistic regression model) and significantly increased protein levels of 4 DDR proteins (ATR, MDM2, p53S15, Chk2T68) in pPBLs from CRs vs. pPBLs from PRs (p&lt;0.05, logistic regression model). We generated a combined DDR Score which positively and significantly correlated with CR vs. PoR (P&lt;0.001, ordinal logistic regression model). From the combined DDR score, using mean score &gt;0.082 as a cutpoint, we could include 90% patients with a CR. Finally, WES analysis of pPBL DNA from 15 CRs and 15 PoRs revealed that CRs were enriched in predicted-pathogenic variants in base excision repair genes vs. PoRs (p&lt;0.01, q&lt;0.025, FDR).

Conclusion and future work: Overall, our data suggests inherent DDR capacity testing may predict the magnitude of benefit from nCRT and assist in patient selection for treatment. Validation in a larger RC patient population is needed to confirm these findings. Biological studies testing the impact of the identified variants in base excision repair on inherent DDR capacity are warranted.

Citation Format: Elena V. Demidova, Randy W. Lesh, Vladimir Avkshtol, Margret B. Einarson, Erica A. Golemis, Sanjeevani Arora, Joshua E. Meyer. Association of DNA damage response capacity with neoadjuvant chemoradiation response in locally advanced rectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 349.

Abstract PR-006: Pulsed low-dose-rate radiation (PLDR) limits pancreatic pro-tumor stroma aggravation: Pre-clinical basis for an ongoing PLDR trail

Radiation, combined with radio-sensitizing chemotherapy, is used preoperatively as neoadjuvant therapy (NT) for borderline resectable pancreatic ductal adenocarcinoma (PDAC) with the intent of facilitating a curative surgical intervention. PDAC is uniquely characterized by an extensive fibrous microenvironment, desmoplasia, which can unintendedly be aggravated by NT to foster its pro-tumoral function. Radiation, as part of NT, is aimed at providing a margin adjacent to un-resectable vessels and sterilizing regional lymph nodes. Yet, to avoid the unintended desmoplastic aggravation, and because of a risk of toxicities associated with high doses due to the radio-sensitivity of adjacent small bowel and stomach, the total dose of NT radiation delivered to PDAC patients is classically modest. Therefore, NT radiation in PDAC patients is often lower than optimal for effective tumor cell elimination. Pulsed low-dose-rate (PLDR) radiation improves the safety of radiation treatment as it allows time for DNA damage repair in non-tumorous cells/tissues while simultaneously remaining as effective as continuous dose rate (CDR) radiation in cancer cells. In theory, PLDR could be amendable for increased radiation dosage. Of interest, the use of PLDR in pre-clinical animal studies revealed a systemic lowering of transforming growth factor beta (TGFβ), a known immunosuppressive factor. Hence, we posit that since cancer-associated fibroblasts (CAFs) produce TGFβ and constitute one of the most abundant cells in PDAC desmoplasia, variations in TGFβ levels in response to NT will inform on desmoplastic dynamic changes. Our team has developed means to assess CAF functions and activation statuses. These efforts were guided by generating a desmoplastic biomarker signature obtained from patient-harvested CAFs during the production of extracellular matrix (ECM), using our well-established in vitro 3D system. We employed this in vivo-mimetic system to test the hypothesis that PLDR limits pro-tumoral desmoplastic CAF aggravation. As part of the CAF functional signature, we tested levels of immunosuppressive TGFβ secretion, expression of netrin-G1, palladin, and others; together with the biogenesis of unique extracellular vesicles, and the production of ECMs capable of nurturing PDAC cells under starvation. During a 5-day assay, human PDAC 3D ECM producing CAFs were treated with gemcitabine (Gem; 5nm) plus 4Gy or 8Gy PLDR vs. CDR. Results indicated that Gem alone or with CDR indeed aggravated CAF’s pro-PDAC phenotype and function, while Gem combined with PDLR limited and sometimes reverted this functional pro-tumor CAF signature. Based on these results, we are poised to test this functional CAF/desmoplasia signature, as laboratory correlatives, in an ongoing clinical trial at Fox Chase Cancer Center. The phase I trial is a dose-escalation study of PLDR radiation and chemotherapy at standard and intensified doses in preoperative pancreatic cancer patients with toxicity, histopathologic, and CAF-informing translational endpoints.

Citation Format: Janusz Franco-Barraza, Tiffany Luong, Jessica K. Wong, Debora B. Vendramini-Costa, Ralph Francescone, Jaye C. Gardiner, Kristopher S. Raghavan, Joshua E. Meyer, Edna Cukierman. Pulsed low-dose-rate radiation (PLDR) limits pancreatic pro-tumor stroma aggravation: Pre-clinical basis for an ongoing PLDR trail [abstract]. In: Proceedings of the AACR Virtual Special Conference on Radiation Science and Medicine; 2021 Mar 2-3. Philadelphia (PA): AACR; Clin Cancer Res 2021;27(8_Suppl):Abstract nr PR-006.

Pancreatic cancer in the era of COVID-19 pandemic: Which one is the lesser of two evils?

Pancreatic adenocarcinoma remains one of the deadliest malignancies affecting the older population. We are experiencing a paradigm shift in the treatment of pancreatic cancer in the era of coronavirus disease 2019 (COVID-19) pandemic. Utilizing neoadjuvant treatment and further conducting a safe surgery while protecting patients in a controlled environment can improve oncological outcomes. On the other hand, an optimal oncologic procedure performed in a hazardous setting could shorten patient survival if recovery is complicated by COVID-19 infection. We believe that oncological treatment protocols must adapt to this new health threat, and pancreatic cancer is not unique in this regard. Although survival may not be as optimistic as most other malignancies, as caregivers and researchers, we are committed to innovating and reshaping the treatment algorithms to minimize morbidity and maximize survival as caregivers and researchers.

Feasibility of using fitness tracker to assess activity level and toxicities in colorectal cancer (CRC) patients (Pts)

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Background: Performance status (PS) is used to predict tolerance and morbidity associated with CRC treatment. Monitoring activity level at the start of therapy using a wearable fitness tracker Fitbit (Fb) may provide a more accurate estimate of a pt’s overall PS and help predict treatment related toxicity (T). Methods: With IRB approval, we prospectively enrolled CRC pts undergoing therapy into 2 cohorts, medical undergoing chemotherapy (M) and surgical undergoing definitive surgery (S). Our objective was to assess feasibility of using Fb to track pt activity level and secondarily correlate with T. After documenting baseline ECOG PS, M and S pts wore Fb for 4 days while receiving chemotherapy or prior to surgery, respectively. Pts’ mean steps per day (SPD) were calculated excluding days Fb was worn <12 hours. To stratify prediction of toxicity risk, a cutoff of 5000 SPD was selected and any post-operative complication (S pts) or ≥grade 3 toxicity (M pts) was counted as T. The study met accrual of 80 pts. Results: On final analysis, 80 pts were evaluated for the primary aim. 68 pts had at least 3 days with ≥12 hours of Fb usage, meeting the 75% feasibility endpoint. 76 pts had at least 1 day with ≥12 hours of Fb usage with data for analysis. SPD correlated with PS and the SPD and active minutes (read by device) for PS 0 and PS 1 pts was 6313 steps and 122 min and 2925 steps and 55 min, respectively (p=0.0003). Rate of T was 25% in pts with PS 0 and 33% in pts with PS 1. With SPD, rate of T was numerically lower in pts with >5000 SPD compared to pts with <5000 SPD (21% vs 32%, p = NS). Conclusions: We observed high rates of compliance with Fb in CRC pts. SPD cutoff of 5000 correlated with ECOG PS 0 vs 1. We observed usefulness of SPD as an identifier for toxicities and suggestion that it may be more reliable compared to PS alone in this small sample of pts. These findings provide rationale to study SPD in conjunction with PS for risk stratification of pts undergoing therapy, and can possibly be incorporated into pre-habilitation selection in high risk groups.

[Table: see text]

Loss of Consciousness is Associated with Increased Neurocognitive Intra-Individual Variability Following Sports-Related Concussion

Purpose

Traditional markers of concussion severity, including loss of consciousness (LOC), retrograde amnesia (RA), and post-traumatic amnesia (PTA), have been inconsistently associated with neurocognitive performance following sports-related concussion. The purpose of this study was to evaluate whether LOC, RA, and PTA influence a particular aspect of post-concussion cognitive functioning—across-test intra-individual variability (IIV).

Methods

Concussed athletes (N=119; 77.3% male) were evaluated, on average, 8.55 days post-concussion (SD=11.27; Mdn=4 days) via clinical interview and neuropsychological assessment. Primary outcomes of interest included two measures of IIV-an average standard deviation (ASD) score and a maximum discrepancy (MD) score-computed from 18 norm-referenced variables.

Results

A one-way ANCOVA adjusting for time since injury revealed a significant effect of LOC on the ASD (F(1, 116)=6.78, p=.010, ηp2=.055) and MD (F(1, 116)=5.65, p=.019, ηp2=.046) scores, such that athletes with LOC displayed significantly greater IIV than athletes without LOC. In contrast, measures of IIV did not significantly differ between athletes who did and did not experience RA or PTA (all p>.05).

Conclusion

LOC, but not RA or PTA, was associated with greater variability, or inconsistencies, in cognitive performance following concussion. This suggests that LOC may be a relevant consideration when evaluating post-concussion cognitive dysfunction. IIV has recently been established as a sensitive measure of cognitive functioning in a variety of clinical samples and has been associated with underlying neurobiological integrity. Taken together, our results implicate LOC as a possible contributing factor of less efficient cognitive functioning following concussion and may help detect athletes at risk for poor clinical outcomes.

Treatment-related toxicity and outcomes in older versus younger patients with esophageal cancer treated with neoadjuvant chemoradiation

BACKGROUND

Neoadjuvant chemoradiation (nCRT) followed by esophagectomy is the standard treatment for locally advanced esophageal cancer. Older patients are often felt to be poor candidates for nCRT. Limited data is available to guide the use of nCRT in this population.

METHODS

A retrospective review of patients treated at a tertiary cancer center between 2002 and 2014 was conducted grouping patients by age (≥ 65 or < 65) for evaluation of differences in toxicity and outcomes. Evaluation of pre-treatment platelet-to-lymphocyte ratio (PLR) and neutrophil-to-lymphocyte ratio (NLR) was also performed. Univariate (UVA) and multivariate analyses (MVA) determined associations between age, toxicities and outcomes. The Kaplan-Meier method (KM) assessed overall survival (OS) and relapse free survival (RFS).

RESULTS

125 patients were identified for this study (67 aging <65, and 58 ≥ 65). In the UVA, advanced age was only associated with increased hematologic toxicity (p = .04). After adjusting for covariates in the MVA, there were no significant differences in toxicity between older and younger patients. There were also no differences between overall survival and relapse free survival between age groups. Increased pre-treatment NLR was strongly correlated with advanced age (p = .01), increased hospitalizations (p = .04), and decreased RFS (p = .002).

CONCLUSIONS

Older patients who underwent nCRT followed by esophagectomy had similar toxicities and outcomes as younger patients suggesting that nCRT before esophagectomy is safe in select older adults with esophageal cancer. PLR and NLR may serve as prognostic markers of aging, toxicity, and outcomes. Further research is warranted to optimize the therapy of older patients with this disease.

Comprehensive Genomic Landscapes in Early and Later Onset Colorectal Cancer

PURPOSE

The incidence rates of colorectal cancers are increasing in young adults. The objective of this study was to investigate genomic differences between tumor samples collected from younger and older patients with colorectal cancer.

EXPERIMENTAL DESIGN

DNA was extracted from 18,218 clinical specimens, followed by hybridization capture of 3,769 exons from 403 cancer-related genes and 47 introns of 19 genes commonly rearranged in cancer. Genomic alterations (GA) were determined, and association with patient age and microsatellite stable/microsatellite instability high (MSS/MSI-H) status established.

RESULTS

Overall genomic alteration rates in the younger (<40) and older (≥50) cohorts were similar in the majority of the genes analyzed. Gene alteration rates in the microsatellite stable (MSS) younger and older cohorts were largely similar, with several notable differences. In particular, TP53 (FDR < 0.01) and CTNNB1 (FDR = 0.01) alterations were more common in younger patients with colorectal cancer, and APC (FDR < 0.01), KRAS (FDR < 0.01), BRAF (FDR < 0.01), and FAM123B (FDR < 0.01) were more commonly altered in older patients with colorectal cancer. In the MSI-H cohort, the majority of genes showed similar rate of alterations in all age groups, but with significant differences seen in APC (FDR < 0.01), BRAF (FDR < 0.01), and KRAS (FDR < 0.01).

CONCLUSIONS

Tumors from younger and older patients with colorectal cancer demonstrated similar overall rates of genomic alteration. However, differences were noted in several genes relevant to biology and response to therapy. Further study will need to be conducted to determine whether the differences in gene alteration rates can be leveraged to provide personalized therapies for young patients with early-onset sporadic colorectal cancer.

Impact of PET/CT for Restaging Patients With Locally Advanced Rectal Cancer After Neoadjuvant Chemoradiation

BACKGROUND

A major challenge in identifying candidates for nonoperative management of locally advanced rectal cancer is predicting pathologic complete response (pCR) following chemoradiation. We evaluated pre- and post-CRT PET-CT imaging to predict pCR and prognosis in this set of patients undergoing resection after neoadjuvant therapy.

METHODS

We retrospectively identified patients from 2002 to 2015 with locally advanced rectal cancer who underwent CRT, pre- and post-CRT PET-CT imaging, and resection. Univariate and multivariate analysis was performed and receiver operating characteristic (ROC) curves were generated to evaluate the association of PET-CT characteristics with pCR and survival. ROC curves were generated to define optimal cutoff points for predictive PET-CT characteristics.

RESULTS

125 patients were included. pCR rate was 28%, and follow-up was 48 mo. On multivariable analysis, patients who had a pCR had lower median post-CRT maximal standardized uptake value (SUV_max) (3.2 versus 5.2, P = 0.009) and higher median %SUV decrease (72 versus 58%, P = 0.009). ROC curves were generated for %SUV_max decrease (AUC = 0.70) and post-CRT SUV (AUC = 0.69). Post-CRT SUV_max <4.3 and %SUV_max decrease of >66% were equally predictive of pCR with a sensitivity of 65%, specificity of 72%, PPV of 44%, and NPV of 86%. Median 5-y overall and relapse-free survival were improved for patients with post-CRT SUV <4.3 (OS: 86 versus 66%, P = 0.01; RFS: 75 versus 52%, P = 0.01) or %SUV decrease of >66% (OS, 82 versus 66%, P = 0.05; RFS, 75 versus 54%, P = 0.01).

CONCLUSIONS

PET/CT may be useful in identifying patients who did not achieve pCR, as well as overall survival in patients undergoing CRT for rectal cancer. Patients with a post-CRT SUV of >4.3 should be considered for operative management, as an estimated 86% of these patients will not have a pCR.

Correlation of peripheral blood markers of DNA damage and immune response with chemoradiation response in patients with locally advanced rectal cancer

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Background: Approximately 60% of newly diagnosed rectal cancers are locally advanced. The standard of care for these malignancies is neoadjuvant chemoradiation therapy (nCRT) followed by surgery. Unfortunately, only approximately 20% of patients experience a complete response, but all are at risk for toxicity. There are no biomarkers to predict who will derive the greatest benefit from CRT. We hypothesized that inherent DNA damage recognition and repair (DNA-DRR) capacity contributes to CRT response in rectal cancer. Methods: We used primary peripheral blood lymphocytes (pPBLs) from rectal cancer patients to study differences in DNA-DRR capacity. The blood samples used were either drawn prior to nCRT or post a standard course of ~5.5 weeks of nCRT. We used immunofluorescence and Luminex-based multianalyte approaches to study DNA-DRR capacity in pPBLs. To determine if the tested biomarkers correlated with CRT response, we segregated patients by neoadjuvant rectal (NAR) score, a validated surrogate endpoint in rectal cancer. Results: Using pPBLs, we found that a subset of patients had elevated phosphorylated histone H2AX (γ-H2AX) foci, a well-described marker of DNA double strand breaks. We found that poor responders (PoR; NAR score > 14; n = 21) had lower γ-H2AX foci then complete responders (CR; NAR score < 1; n = 21) (P < 0.0001, Kruskal-Wallis test). We also did not observe any significant differences in γ-H2AX foci from pPBLs drawn prior to CRT versus post nCRT (p = 0.519, n = 11, Wilcoxon rank sum test). Next, by multianalyte testing, we found that a combined score derived from six DNA-DRR markers (ATR, MDM2, phosphorylated forms of H2AX (γ), p53, Chk1, Chk2) strongly correlated with CR (p < 0.001). Finally, by multianalyte testing, we also detected a serum signature of inflammatory markers that significantly correlated with CRT response (p < 0.05). Conclusions: Our data suggest that rectal cancer patients who differ in their response to CRT differ in global, inherent DNA-DRR capacity, suggesting that DNA-DRR capacity in pre-treatment pPBLs can form the basis of a predictive biomarker. This predictive capacity may reflect underlying epigenetic or genetic differences, or inflammatory state. Validation and further development of this novel assay is warranted, as it has the capacity to substantially improve patient selection in an era with growing treatment options for these patients.

Differential chemokine expression patterns in tonsillar disease

Expression profiles of CXC- and CC-chemokines in various forms of tonsillar disease were studied to evaluate whether certain chemokines play a predominant role in a specific subset of tonsillar disease. Total RNA was isolated from 89 biopsies (21 hyperplastic palatine tonsils, 25 adenoids, 16 chronic inflammatory palatine tonsils and 27 chronic inflammatory palatine tonsils with histological prove of acute inflammation), reverse transcribed and subjected to PCR amplifying IL-8, Gro-alpha, eotaxin-1, eotaxin-2, MCP-3, MCP-4 and RANTES. 2% agarose gel electrophoresis revealed a predominance of IL-8 in the chronic inflammatory palatine tonsil group compared to tonsillar hyperplasia. Furthermore, eotaxin-2 was strongly overexpressed in adenoid samples compared to chronic inflammatory specimens. Our data suggest that the majority of diseases related to adenoid formation are mediated via an eotaxin-2 expression, whereas chronic inflammatory tonsillitis is associated with IL-8 upregulation. These data imply that adenoids are related to a Th-2, and chronic inflammatory tonsillitis to a Th-1 based immune response.

Measuring liver radioembolization dose with positron emission tomography

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Background: There is no established way to measure radiation dose deposition during liver radioembolization to help quantify the shortcomings of prescription calculations, which do not consider size, shape, and location of tumors. We aimed to establish a standardized method of radioembolization dose measurement though a novel technique using Positron Emission Tomography and Computed Tomography (PET-CT). Methods: Patients who were recommended for liver radioembolization treatment were enrolled in a prospective single-arm registry study. Index lesions were contoured on the patients’ CT simulation scans. Immediate post-treatment PET/CTs were used to measure the deposited radiation dose by capturing the positron emission from the Yttrium-90’s daughter nuclei. The CT simulation scans were fused to the post-treatment PET/CT scans using rigid registration around the index lesions. The primary dosimetric outcomes were mean dose and dose to 70% of the tumor volume (D70). The optimal mean dose and D70 were > 100 Gy and > 70 Gy, respectively. Results: From November 2014 to November 2015, fifteen consecutive patients with either hepatocellular carcinoma (n = 4) or liver metastases (n = 11) were enrolled in the study. A total of 43 index lesions were contoured with a mean and median size of 18.2 cc and 5.4 cc, respectively. The average mean dose to the index lesions was 99.9 Gy (mean dose range: 2 – 298 Gy; Table). The mean and median D70 were 66.9 Gy and 71 Gy, respectively (range: 1.4 – 211 Gy; standard deviation [SD]: 40.3 Gy). The mean and median D90s were 43 Gy and 41 Gy, respectively. A total of 20 (46.5%) lesions received optimal mean dose and 23 (53.5%) lesions received optimal D70 dose. Conclusions: We established a successful standardized procedure utilizing PET/CT scans to measure the radiation dose delivered during liver radioembolization. The range of the doses received by the tumors underlines the need to collect dosimetric data for future treatment optimization. Dosimetric parameters. Clinical trial information: NCT02088775. [Table: see text]

The association of age with acute toxicities in NRG oncology combined modality lower GI cancer trials

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Background: This study sought to compare adverse events (AEs) of older and younger adults with lower gastrointestinal (GI) malignancies treated on NRG studies. Methods: Data from six NRG trials (RTOG 9811/0012/0247/0529/0822 & NSABP R-04), testing combined modality therapy (radiation and chemotherapy) in patients with anal or rectal cancer, were collected to test the hypothesis that older age was associated with increase in acute ( ≤ 90 days from treatment start) AEs. AEs were defined as GI, Genitourinary (GU), hematologic, or skin. AEs and compliance with protocol-directed therapy were compared between patients aged ≥ 70 years and < 70 years. Categorical variables were compared across age groups using the chi-square test. The association of age on AEs was evaluated using a covariate-adjusted logistic regression model, with odds ratio (OR) reported. To adjust for multiple comparisons, a p-value < 0.01 was considered statistically significant. Results: Data from 2525 patients were collected (43% female, 72% rectal cancer). There were 380 patients ≥ 70 years old (15%). Older patients were more likely to have worse baseline performance status (PS 1 or 2) (23% vs. 16%, p <0.01), but otherwise baseline characteristics were similar. Older patients were less likely to have completed their chemotherapy (78% vs. 87%, p < 0.01), but had similar median RT duration. On univariate analysis, patients ≥ 70 were more likely to experience grade ≥ 3 GI AEs (36% vs. 23%, OR 1.82, p < 0.001), and less likely to experience ≥ 3 skin AEs (8% vs. 14%, OR 0.56, p = 0.002). There was no difference between GU or hematologic AEs. On multivariable analysis, age ≥ 70 was associated with grade ≥ 3 GI AE (OR 1.80, 95% CI: 1.40, 2.31; p < 0.001) after adjusting for gender, PS, T stage, disease site, RT duration, and chemotherapy completion. Conclusions: Older patients with curable lower GI cancers who underwent combined-modality therapy were less likely to complete chemotherapy and were more likely to experience serious GI toxicity, whereas younger patients had higher rates of serious skin AEs.

Nutrition and exercise patterns in survivors of esophageal and gastroesophageal junction (EGEJ) cancers

89

Background: While obesity is a risk factor for EGEJ, malnutrition is common at diagnosis (dx) and can be exacerbated by neoadjuvant therapy (NAT) and esophagectomy. Little is known regarding nutrition and exercise patterns of EGEJ cancer survivors. Methods: A survey of EGEJ survivors > 12 months from esophagectomy was conducted. Pts were identified using institutional tumor registry. The Dillman mailed survey method was used. Questionnaires regarding health behaviors were employed: Godin Leisure-Time Exercise [GLTQ], Cancer Appetite and Symptom [CASQ], Nutritional Self-Efficacy (NSEQ). Chart review included demographics, pt characteristics and therapy received. Spearman correlation, Wilcoxon and Fisher’s tests assessed relationships between groups or variables. Results: Forty one of 140 eligible pts (29%) returned questionnaires and had surgery between 1991-2014. Median age was 69 and 78% were male. Most (83%) had adenocarcinoma. On presentation, 73% had clinical stage II or III disease and 76% received NAT. Median time from dx was 5 years (range 2-25). Mean weight loss from dx to current was 38 lbs. Mean BMI (kg/m2) was 29.52 at dx and 24.15 at most recent clinic visit. Obesity was present in 37% of pts at dx, but only 7% of survivors. Mean health behavior scores (SD): GLTQ 22.10 (22.93), CASQ 31.74 (6.66), and NSEQ 11.39 (4.03). Age, marital status, gender, education, and income were not associated with GLTQ, CASQ or NSEQ. Sedentary lifestyle (SL) with GTLQ score < 14 was present in 46% of survivors and associated with overweight BMI (mean 26.7 for SL vs 23.7 for non-SL; p = 0.04). There was a significant positive correlation between current BMI and NSEQ score (r = 0.68; p = 0.03). Conclusions: Many EGEJ cancer pts present with obesity but subsequently lose weight after curative therapy. The mean CASQ score in our population is similar to other GI cancer populations, suggesting that residual symptoms persist years after treatment ends. There is a high prevalence of SL in survivors which is associated with being overweight. Higher levels of nutrition self-efficacy were also associated with a higher current BMI. Future studies should define strategies to optimize nutrition and exercise habits in EGEJ cancer survivors.

Evaluating the prognostic significance of lymphovascular invasion in stage II and III colon cancer

685

Background: Presence of lymphovascular invasion (LVI) is known to be a predictor of lymph node involvement in colon adenocarcinoma (CA). Lymph node involvement is associated with poorer prognosis necessitating adjuvant therapy. While some studies have suggested that LVI is a predictor of worse overall survival in early stage colon cancer, the significance of LVI on prognosis has not been tested in a comprehensive North American data set. Methods: Patients with stage II and III CA with LVI data available and those who received predefined standard of care treatment were identified from the National Cancer Data Base (NCDB) from 2011 to 2015. The relationship between LVI and overall survival was tested using Kaplan-Meier survival curves and Cox proportional hazards regression analysis after adjusting for relevant clinical and demographic variables. Hazard ratios and 95% confidence intervals are reported along with median overall survival (OS) where available. Results: The dataset included 93,070 patients with stage II and 66,701 patients with stage III CA. The proportion of patients with LVI was 13% in stage II and 47% in stage III CA. After adjusting for age, sex, gender, race, comorbidities, socioeconomic status, T, and N stage, LVI was associated with worse OS in stage II, HR 1.2 (1.15-1.25, p < 0.001), and in stage III, HR 1.25 (1.21-1.30, p < 0.001), CA. Median OS was 6.51 years with LVI versus. 6.85 years without LVI in stage II compared with 6.57 years with LVI versus not reached without LVI in stage III CA. Of the stage II patients with LVI, 20% received adjuvant chemotherapy (CT) and median OS was 6.91 years for those who did versus 6.07 years for those who did not receive CT. Conclusions: Our data suggest that LVI is an important predictor of OS in stage II and III CA. There is evidence that adjuvant chemotherapy improves OS in advanced CA but there remains uncertainty as to the benefit in stage II. Despite this uncertainty, guidelines suggest consideration of adjuvant CT in patients with high-risk stage II disease. Our data support the recommendation that LVI be considered a high-risk feature in stage II disease. Further studies are necessary to examine whether the type or duration of CT should differ for patients with CA and LVI.

Stage II and III rectal adenocarcinoma outcomes related to lymphovascular invasion

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Background: Lymphovascular invasion (LVI) has been shown to be associated with nodal involvement and higher rates of local recurrence in rectal cancer. In some studies, the presence of LVI has also been associated with worse overall survival; however, these have been mostly smaller, single institution studies or incomplete data sets. Our goal was to examine the effect of LVI on prognosis in a large and inclusive database. Methods: Outcomes of patients with clinical stage II and stage III rectal adenocarcinoma in the National Cancer Data Base (NCDB) from 2011 to 2015, in whom LVI data was available, were included. Exclusion criteria incorporated patients who did not receive neoadjuvant radiation and chemotherapy, neoadjuvant or adjuvant. Overall survival was compared in patients with and without LVI, controlling for age, sex, race, comorbidities, socioeconomic factors, and T and N stages using Kaplan-Meier survival curves and Cox proportional hazards regression analysis. Median overall survival and hazard ratios with 95% confidence intervals are reported where available. Results: The dataset included 9206 patients with stage II and 12640 patients with stage III rectal adenocarcinoma for which LVI data were available and who received the study’s previously defined standard of care. The proportion of patients with LVI was 11% in stage II and 16% in stage III rectal cancer. After adjusting for age, sex, race, T or N stage, and other clinical and demographic variables, LVI was associated with worse overall survival in stage II HR 1.87 (1.62-2.16, p < 0.001) and in stage III HR 1.8 (1.61-2.02, p < 0.001) rectal cancer. The median overall survival was not reached in stage II rectal cancer patients without LVI versus 5.73 years with LVI. In stage III rectal cancer, the median overall survival was 6.91 years without LVI versus 6.21 years with LVI. Conclusions: Lymphovascular invasion is an independent risk factor of mortality in stage II and III rectal cancer. Stage II rectal cancer patients without LVI have comparatively good survival of the groups studied, potentially identifying a group of patients that may benefit from de-escalated therapy. Further studies will be guided at identifying if benefits with chemotherapy are associated with LVI status.

Feasibility of using a fitness tracker to assess activity level and toxicity in colorectal cancer patients

684

Background: Performance status (PS) is traditionally used to predict tolerance and morbidity associated with colorectal cancer (CRC) treatment. Monitoring activity level at the start of therapy using a wearable fitness tracker (Fitbit) may provide a more accurate estimate of overall patient (pt) PS and help predict treatment-related toxicity. Methods: With IRB approval, we prospectively enrolled CRC pts undergoing therapy into two cohorts: medical (M) and surgical (S). Our primary aim was to assess the feasibility of using Fitbit to assess activity level and toxicity. After documenting baseline ECOG PS, M and S pts wore Fitbit for four days while receiving chemotherapy or prior to surgery, respectively. Pts’ mean steps per day (SPD) were calculated, excluding days Fitbit was worn < 12 hours. To stratify the prediction of toxicity risk, a cutoff of 5,000 SPD was selected and any post-operative complication (S pts) or ≥ grade 3 toxicity (M pts) was counted as toxicity. The study is ongoing to accrue 80 pts. Results: On interim analysis, 43 pts were evaluated for the primary aim. Seventy nine percent (34/43) of pts had at least 3 days with ≥ 12 hours of Fitbit usage, meeting the 75% feasibility endpoint. Forty pts (25 M, 15 S) had at least 1 day with ≥ 12 hours of Fitbit usage and had data available for analysis. Mean SPD for PS 0 and PS 1 pts was 7,183 and 3,214, respectively (p=0.01), and overall was 6,290 (SD 4,416). Eight M pts and 2 S pts experienced toxicity (Table). The rate of toxicity was 23% (7/30) in pts with PS 0 and 33% (3/10) in pts with PS 1. With SPD as cutoff, the toxicity rate was 11% (2/19) in pts with > 5000, compared to 38% (8/21) in pts with < 5000. Conclusions: We observed high rates of compliance with a fitness tracker in CRC pts. SPD serves as a useful identifier for toxicity and may be a better predictor than traditional PS. These findings provide rationale to study SPD in lieu of PS for risk stratification of patients undergoing therapy and possibly incorporate pre-habilitation programs in high-risk groups, though validation in larger studies is needed. [Table: see text]

External beam radiation therapy (EBRT) for asymptomatic bone metastases in patients with solid tumors reduces the risk of skeletal-related events (SREs)

BACKGROUND

The potential benefit of administering external beam radiation therapy (EBRT) to patients with asymptomatic bone metastases has rarely been addressed in clinical investigations. The aim of this study was to determine if cancer patients who were treated with EBRT for asymptomatic bone metastases experienced later onset of pain and skeletal-related events (SREs) than those who were untreated.

METHODS

A retrospective chart review was conducted for prostate, breast, and lung cancer patients with asymptomatic bone metastases treated at a single cancer center from 2007 to 2017. Patients who received EBRT for asymptomatic bone metastases were compared to those who received medical or supportive therapy only.

RESULTS

When all cancer groups were combined, the median time from the diagnosis of asymptomatic bone metastases to either moderate-to-severe pain or an SRE was 25 months for the untreated patients and 81 months for the patients receiving EBRT (P<0.001). The delay in the first occurrence of pain or an SRE following EBRT was observed for patients with prostate cancer (P=0.025) and lung cancer (P=0.029) but not for patients with breast cancer. In a multivariate analysis, EBRT was again shown to reduce the risk of developing pain or an SRE when all cancer types were combined (P=0.006). OS was not altered by EBRT.

CONCLUSIONS

EBRT administered to a group of prostate, lung, and breast cancer patients with asymptomatic bone metastases was associated with an increase in time to the first occurrence of either pain or an SRE. These data demonstrate that there may be clinical settings in which EBRT should be used to delay or prevent late complications of bone metastases that are asymptomatic at the time of diagnosis.

Concurrent chemoradiation for resected gall bladder cancers and cholangiocarcinomas

Background

Gallbladder cancer (GBC) and cholangiocarcinoma (CCA) are rare entities with relatively poor prognoses. We compared treatment outcomes of definitive resection with or without neoadjuvant therapy in GBC and CCA patients.

Methods

All non-metastatic GBC and CCA patients at a single institution who underwent definitive resection from 1992-2016 were analyzed. We compared overall survival (OS), locoregional failure (LRF) and distant failure (DF) in patients who received neoadjuvant therapy (chemotherapy and/or radiation) versus those who did not receive neoadjuvant treatment. OS was analyzed using the Kaplan-Meier method and log rank tests. Cox proportional hazard models were used to analyze time to recurrence.

Results

Out of 128 patients, 90 had GBC and 38 had CCA, 25 patients (27%) among GBC and 8 patients (21%) with CCA were T3, T4 or node positive. Overall, 52 (40%) GBC and 25 (20%) CCA patients received neoadjuvant treatment, chemotherapy alone 60 patients (47%) or radiation with or without chemotherapy 17 patients (13%). Chemotherapy was single agent in 44 patients (34%) and multi-agent in 25 (20%). The median OS for GBC patients was 3.1 years with 2.6 years for no neoadjuvant group and 3.1 years for neoadjuvant group (P=0.6786). Median OS was 2.6 years for CCA patients, 3.6 years for no neoadjuvant therapy versus 2.0 years for neoadjuvant group (P=0.1613). There was a trend towards increased DF in patients with CCA and GBC receiving neoadjuvant therapy: HR 2.74, 95% CI, 0.73-10.3, P=0.14 and 0.92, 95% CI, 0.44-1.93, P=0.82 respectively. The hazard ratio for time to LRF in CCA patients receiving neoadjuvant treatment was 3.17, 95% CI, 0.62-16.31, P=0.16 whereas HR was 0.15, 95% CI, 0.10-1.76, P=0.23 for GBC patients. Among GBC patients, the pattern of first failure was locoregional in 8 (10%) having 3 LRF in neoadjuvant group (2 with chemotherapy, 1 with CRT, 0 with RT alone) as compared to 5 in adjuvant group. Among 28 (35%) patients with DF first, 15 patients received neoadjuvant therapy versus 13 patients in non-neoadjuvant group. In CCA patients, LRF occurred first in 6 patients receiving neoadjuvant treatment (3 with chemotherapy, 1 with CRT, 2 with RT alone) as compared to 2 patients who were treated with non-neoadjuvant CRT. DF was the first site of failure in 9 patients treated with neoadjuvant CRT (8 with chemotherapy, 0 with CRT and 1 with RT alone) as compared to 4 patients without neoadjuvant treatment.

Conclusions

In this retrospective data set, a trend towards better survival was seen in adjuvantly treated CCA patients, but not in GBC patients. Recurrence patterns also appear different among the two, which might be attributed to treatment modality used, patient selection or unmeasured factors.

Keywords

Gallbladder cancer (GBC); cholangiocarcinoma (CCA); neoadjuvant; resection; chemoradiation; chemotherapy.

Predictive Value of Leukocyte- and Platelet-Derived Ratios in Rectal Adenocarcinoma

BACKGROUND

Advances in treatment of rectal cancer have improved survival, but there is variability in response to therapy. Recent data suggest the utility of the lymphocyte-to-monocyte ratio (LMR), neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR) in predicting survival. Our aim was to examine these ratios in rectal cancer patients and determine whether any association exists with overall survival (OS).

METHODS

Using prospectively maintained institutional data, a query was completed for clinical stage II-III rectal adenocarcinoma patients treated from 2002 to 2016. We included patients who had a complete blood count collected before neoadjuvant chemoradiation (pre-CRT) and again before surgery (post-CRT). The LMR, NLR, and PLR were calculated for the pre-CRT and post-CRT time points. Potential cutpoints associated with OS differences were determined using maximally selected rank statistics. Survival curves were compared using log-rank tests and were adjusted for age and stage using Cox regression.

RESULTS

A total of 146 patients were included. Cutpoints were significantly associated with OS for pre-CRT ratios but not for post-CRT ratios. Within the pretreatment group, a "low" (<2.86) LMR was associated with decreased OS (log-rank P = 0.004). In the same group, a "high" (>4.47) NLR and "high" PLR (>203.6) were associated with decreased OS (log-rank P < 0.001). With covariate adjustment for age, and separately for final pathologic stage, the associations between OS and LMR, NLR, and PLR each retained statistical significance.

CONCLUSIONS

If obtained before the start of neoadjuvant chemoradiation, LMR, NLR, and PLR values are accurate predictors of 5-y OS in patients with locally advanced rectal adenocarcinoma.

Local Control and Toxicity of External Beam Reirradiation With a Pulsed Low-dose-rate Technique

PURPOSE

To evaluate the efficacy and toxicity of external beam reirradiation using a pulsed low-dose-rate (PLDR) technique.

METHODS AND MATERIALS

We evaluated patients treated with PLDR reirradiation from 2009 to 2016 at a single institution. Toxicity was graded using the Common Terminology Criteria for Adverse Events, version 4.0, and local control was assessed using the Response Evaluation Criteria In Solid Tumors, version 1.1. On univariate analysis (UVA), the χ2 and Fisher exact tests were used to assess the toxicity outcomes. Competing risk analysis using cumulative incidence function estimates were used to assess local progression.

RESULTS

A total of 39 patients were treated to 41 disease sites with PLDR reirradiation. These patients had a median follow-up time of 8.8 months (range 0.5-64.7). The targets were the thorax, abdomen, and pelvis, including 36 symptomatic sites. The median interval from the first radiation course and reirradiation was 26.2 months; the median dose of the first and second course of radiation was 50.4 Gy and 50 Gy, respectively. Five patients (13%) received concurrent systemic therapy. Of the 39 patients, 9 (23%) developed grade ≥2 acute toxicity, most commonly radiation dermatitis (5 of 9). None developed grade ≥4 acute or subacute toxicity. The only grade ≥2 late toxicity was late skin toxicity in 1 patient. On UVA, toxicity was not significantly associated with the dose of the first course of radiation or reirradiation, the interval to reirradiation, or the reirradiation site. Of the 41 disease sites treated with PLDR reirradiation, 32 had pre- and post-PLDR scans to evaluate for local control. The local progression rate was 16.5% at 6 months and 23.8% at 12 months and was not associated with the dose of reirradiation, the reirradiation site, or concurrent systemic therapy on UVA. Of the 36 symptomatic disease sites, 25 sites (69%) achieved a symptomatic response after PLDR, including 6 (17%) with complete symptomatic relief.

CONCLUSION

Reirradiation with PLDR is effective and well-tolerated. The risk of late toxicity and the durability of local control were limited by the relatively short follow-up duration in the present cohort.

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.