Feasibility of establishing and drug screening patient-derived rectal organoid models from pretreatment rectal cancer biopsies

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Background: Response to neoadjuvant chemotherapy and radiation therapy in the treatment of locally advanced rectal cancer is heterogenous and prognostic of clinical outcomes, necessitating the need for predictive biomarkers to guide personalized treatment recommendations. Sensitivity to a given chemotherapy in patient-derived organoids predicts patient response to that chemotherapy, establishing it as a promising model for efforts to ascertain predictive biomarkers and personalize treatment decisions. This study assessed the feasibility of obtaining patient-derived rectal organoids from standard of care pre-treatment proctoscopy biopsies. Methods: In this clinical trial (NCT04371198), biopsies were obtained from patients with stage II rectal adenocarcinoma prior to receipt of neoadjuvant therapy. Tissue samples were mechanically and enzymatically dissociated to obtain a single cell suspension. Cells were then mixed with matrigel at a ratio of 2,000 cells:5 µL Matrigel in a 50ul dome and plated on a 24 well tissue culture plate with colorectal cancer organoid media at 37oC/5% CO2. Established patient-derived organoids were then used to perform drug screens with clinically-applicable chemotherapeutics including oxaliplatin, irinotecan and 5-FU, followed by high throughput drug screen using our recently published MicroOrganoSpheres platform using the NCI Approved Oncology Drugs Set VI* library. Results: Of the 20 patients enrolled, 17 (85%) patient-derived organoids were created from pre-treatment specimens. 15 (88%) of these samples were successfully established as defined by the ability to passage organoids for at least two passages. All established samples were used to perform standard of care drug screens and high throughout drug screens, which demonstrated differences in drug sensitivities among the samples. Moreover, within two weeks of receiving the sample, four established quickly enough to complete drug screening with oxaliplatin, SN38, and 5-Fluorouracil. Conclusions: These results demonstrate the feasibility of establishing patient-derived rectal organoids from biopsy specimens obtained by proctoscopy, and reinforce the utility of patient-derived organoids as a tractable ex vivo platform to personalize rectal cancer treatment. Planned future directions include in vitro determination of radiation therapy sensitivity as well as systematic assessment of the correlation between individual patients and their organoid model. Clinical trial information: NCT04371198 .

Comparing Outcomes of Oligometastases Treated with Hypofractionated Image-Guided Radiotherapy (HIGRT) with a Simultaneous Integrated Boost (SIB) Technique versus Metastasis Alone: A Multi-Institutional Analysis

Simple Summary

Hypofractionated image-guided radiotherapy (HIGRT) is a common method in which high doses of radiation are delivered to treat oligometastatic disease. We have previously reported on the clinical outcomes of treating oligometastases with radiation using an elective simultaneous integrated boost technique (SIB), delivering higher doses to known metastases and reduced doses to adjacent bone or nodal basins. Here we compare outcomes of oligometastases receiving radiation targeting metastases alone (MA) versus those treated via an SIB. Both SIB and MA irradiation of oligometastases achieved high rates of tumor metastases control and similar pain control. Further investigation of this technique with prospective trials is warranted.

Abstract

Purpose: We previously reported on the clinical outcomes of treating oligometastases with radiation using an elective simultaneous integrated boost technique (SIB), delivering higher doses to known metastases and reduced doses to adjacent bone or nodal basins. Here we compare outcomes of oligometastases receiving radiation targeting metastases alone (MA) versus those treated via an SIB. Methods: Oligometastatic patients with ≤5 active metastases treated with either SIB or MA radiation at two institutions from 2013 to 2019 were analyzed retrospectively for treatment-related toxicity, pain control, and recurrence patterns. Tumor metastasis control (TMC) was defined as an absence of progression in the high dose planning target volume (PTV). Marginal recurrence (MR) was defined as recurrence outside the elective PTV but within the adjacent bone or nodal basin. Distant recurrence (DR) was defined as any recurrence that is not within the PTV or surrounding bone or nodal basin. The outcome rates were estimated using the Kaplan–Meier method and compared between the two techniques using the log-rank test. Results: 101 patients were treated via an SIB to 90 sites (58% nodal and 42% osseous) and via MA radiation to 46 sites (22% nodal and 78% osseous). The median follow-up among surviving patients was 24.6 months (range 1.4–71.0). Of the patients treated to MA, the doses ranged from 18 Gy in one fraction (22%) to 50 Gy in 10 fractions (50%). Most patients treated with an SIB received 50 Gy to the treated metastases and 30 Gy to the elective PTV in 10 fractions (88%). No acute grade ≥3 toxicities occurred in either cohort. Late grade ≥3 toxicity occurred in 3 SIB patients (vocal cord paralysis and two vertebral body compression), all related to the high dose PTV and not the elective volume. There was similar crude pain relief between cohorts. The MR-free survival rate at 2 years was 87% (95% CI: 70%, 95%) in the MA group and 98% (95% CI: 87%, 99%) in the SIB group (p = 0.07). The crude TMC was 89% (41/46) in the MA group and 94% (85/90) in the SIB group. There were no significant differences in DR-free survival (65% (95% CI: 55–74%; p = 0.24)), disease-free survival (60% (95% CI: 40–75%; p = 0.40)), or overall survival (88% (95% CI: 73–95%; p = 0.26)), between the MA and SIB cohorts. Conclusion: Both SIB and MA irradiation of oligometastases achieved high rates of TMC and similar pain control, with a trend towards improved MR-free survival for oligometastases treated with an SIB. Further investigation of this technique with prospective trials is warranted.

Brain Metastases from Esophageal Squamous Cell Carcinoma: Clinical Characteristics and Prognosis

Purpose

Due to the low incidence of intracranial disease among patients with esophageal cancer (EC), optimal management for these patients has not been established. The aim of this real-world study is to describe the clinical characteristics, treatment approaches, and outcomes for esophageal squamous cell carcinoma (ESCC) patients with brain metastases in order to provide a reference for treatment and associated outcomes of these patients.

Methods

Patients with ESCC treated at the Fourth Hospital of Hebei Medical University between January 1, 2009 and May 31,2020 were identified in an institutional tumor registry. Patients with brain metastases were included for further analysis and categorized by treatment received. Survival was evaluated by the Kaplan-Meier method and Cox proportional hazards models.

Results

Among 19,225 patients with ESCC, 66 (0.34%) were diagnosed with brain metastases. Five patients were treated with surgery, 40 patients were treated with radiotherapy, 10 with systemic therapy alone, and 15 with supportive care alone. The median follow-up time was 7.3 months (95% CI 7.4-11.4). At last follow-up, 59 patients are deceased and 7 patients are alive. Median overall survival (OS) from time of brain metastases diagnosis was 7.6 months (95% CI 5.3-9.9) for all cases. For patients who received locoregional treatment, median OS was 10.9 months (95% CI 7.4-14.3), and survival rates at 6 and 12 months were 75.6% and 37.2%, respectively. For patients without locoregional treatment, median OS was 3.0 months (95% CI 2.5-3.5), and survival rates at 6 and 12 months were 32% and 24%, respectively. OS was significantly improved for patients who received locoregional treatment compared to those treated with systematic treatment alone or supportive care (HR: 2.761, 95% CI 1.509-5.053, P=0.001). The median OS of patients with graded prognostic assessment (GPA) score 0-2 was 6.4 months, compared to median OS of 12.3 months for patients with GPA >2 (HR: 0.507, 95% CI 0.283-0.911).

Conclusion

Brain metastases are rare in patients with ESCC. GPA score maybe a useful prognostic tool for ESCC patients with brain metastases. Receipt of locoregional treatment including brain surgery and radiotherapy was associated with improved survival.

Ipilimumab and Radiation in Patients with High-risk Resected or Regionally Advanced Melanoma

PURPOSE

In this prospective trial, we sought to assess the feasibility of concurrent administration of ipilimumab and radiation as adjuvant, neoadjuvant, or definitive therapy in patients with regionally advanced melanoma.

PATIENTS AND METHODS

Twenty-four patients in two cohorts were enrolled and received ipilimumab at 3 mg/kg every 3 weeks for four doses in conjunction with radiation; median dose was 4,000 cGy (interquartile range, 3,550-4,800 cGy). Patients in cohort 1 were treated adjuvantly; patients in cohort 2 were treated either neoadjuvantly or as definitive therapy.

RESULTS

Adverse event profiles were consistent with those previously reported with checkpoint inhibition and radiation. For the neoadjuvant/definitive cohort, the objective response rate was 64% (80% confidence interval, 40%-83%), with 4 of 10 evaluable patients achieving a radiographic complete response. An additional 3 patients in this cohort had a partial response and went on to surgical resection. With 2 years of follow-up, the 6-, 12-, and 24-month relapse-free survival for the adjuvant cohort was 85%, 69%, and 62%, respectively. At 2 years, all patients in the neoadjuvant/definitive cohort and 10/13 patients in the adjuvant cohort were still alive. Correlative studies suggested that response in some patients were associated with specific CD4+ T-cell subsets.

CONCLUSIONS

Overall, concurrent administration of ipilimumab and radiation was feasible, and resulted in a high response rate, converting some patients with unresectable disease into surgical candidates. Additional studies to investigate the combination of radiation and checkpoint inhibitor therapy are warranted.

Do Higher Radiation Doses with Concurrent Chemotherapy in the Definitive Treatment of Esophageal Cancer Improve Outcomes? A Meta-Analysis and Systematic Review

Background: To investigate the effects and safety profile of radiation dose escalation utilizing computerized tomography (CT) based radiotherapy techniques (including 3-Dimensional conformal radiotherapy, intensity-modulated radiotherapy and proton therapy) in the definitive treatment of patients with esophageal carcinoma (EC) with definitive concurrent chemoradiotherapy (dCCRT). Methods: All relevant studies utilizing CT-based radiation planning, comparing high-dose (≥ 60 Gy) versus standard-dose (50.4 Gy) radiation for patients with EC were analyzed for this meta-analysis. Results: Eleven studies including 4946 patients met the inclusion criteria, with 96.5% of patients diagnosed with esophageal squamous cell carcinoma (ESCC). The high-dose group demonstrated a significant improvement in local-regional failure (LRF) (OR 2.199, 95% CI 1.487-3.253; P<0.001), two-year local-regional control (LRC) (OR 0.478, 95% CI 0.309-0.740; P=0.001), two-year overall survival (OS) (HR 0.744, 95% CI 0.657-0.843; P<0.001) and five-year OS (HR 0.683, 95% CI 0.561-0.831; P<0.001) rates relative to the standard-dose group. In addition, there was no difference in grade ≥ 3 radiation-related toxicities and treatment-related deaths between the groups. Conclusion: Under the premise of controlling the rate of toxicities, doses of ≥ 60 Gy in CT-based dCCRT of ESCC patients might improve locoregional control and ultimate survival compared to the standard-dose dCCRT. While our review supports a dose-escalation approach in these patients, multiple ongoing randomized trial initial and final reports are awaited to evaluate the effectiveness of this strategy.

Multi-Institutional Analysis of Synchronous Prostate and Rectosigmoid Cancers

Purpose: To perform a multi-institutional analysis of patients with synchronous prostate and rectosigmoid cancers.

Materials and Methods: A retrospective review of Duke University and Durham Veterans Affairs Medical Center records was performed for men with both prostate and rectosigmoid adenocarcinomas from 1988 to 2017. Synchronous presentation was defined as symptoms, diagnosis, or treatment of both cancers within 12 months of each other. The primary study endpoint was overall survival. Univariate and multivariable Cox regression was performed.

Results: Among 31,883 men with prostate cancer, 330 (1%) also had rectosigmoid cancer and 54 (16%) of these were synchronous. Prostate cancer was more commonly the initial diagnosis (59%). Fifteen (28%) underwent prostatectomy or radiotherapy before an established diagnosis of rectosigmoid cancer. Stage I, II–III, or IV rectosigmoid cancer was present in 26, 57, and 17% of men, respectively. At a median follow-up of 43 months, there were 18 deaths due rectosigmoid cancer and two deaths due to prostate cancer. Crude late grade ≥3 toxicities include nine (17%) gastrointestinal and six (11%) genitourinary. Two anastomotic leaks following low anterior resection occurred in men who received a neoadjuvant radiotherapy prostate dose of 70.6–76.4 Gy. Rectosigmoid cancer stages II–III (HR 4.3, p = 0.02) and IV (HR 16, p < 0.01) as well as stage IV prostate cancer (HR 31, p < 0.01) were associated with overall survival on multivariable analysis.

Conclusions: Synchronous rectosigmoid cancer is a greater contributor to mortality than prostate cancer. Men aged ≥45 with localized prostate cancer should undergo colorectal cancer screening prior to treatment to evaluate for synchronous rectosigmoid cancer.

Evaluating treatment protocols for rectal squamous cell carcinomas: the Duke experience and literature

Background

Colorectal cancer is the third most common cancer in the United States and associated with significant morbidity and mortality. Within colorectal cancer histologies, squamous cell carcinomas (SCC) are rare compared to adenocarcinomas, with only about 200 cases reported to date. Because rectal SCC is rarely encountered, there is a lack of literature and clinical consensus surrounding its optimal treatment approach. Staging and management of SCC can be partly analogous to both rectal adenocarcinoma and anal canal SCC, which leads to a dilemma in how to best approach these patients. As large randomized prospective trials are unrealistic in the setting of this rare malignancy, this study evaluates an institutional experience and reviews the existing literature to help guide future management approaches.

Methods

This retrospective study compared various treatment regimens for rectal SCC patients treated at Duke University Medical Center from January 1, 1980 through December 31, 2016. Patients ≥18 years old with histologically confirmed, nonmetastatic rectal SCC were included. Due to small sample size, all statistical analyses were descriptive. For our systematic review, a comprehensive search of PubMed from 1933 to March 2018 was performed, with selected articles referenced to ensure all relevant publications were included. A qualitative analysis was performed to examine patient diagnoses, treatments, and disease- and treatment-related outcomes.

Results

Eight patients were included. Three patients underwent initial, curative attempt surgery and two of these patients required colostomy. With follow-up ranging from 7.1 to 31.5 months, one patient was alive with no evidence of disease while two developed local/regional recurrences. Five patients received definitive chemoradiation. Of these, three patients developed local/regional and/or metastatic recurrence. Two patients achieved complete response on imaging and currently remain disease-free (follow-up of 31.5 and 33.6 months).

Conclusions

Although the review of our institutional experience is limited by small numbers, our analysis suggests that definitive chemoradiation therapy is the preferred treatment approach to rectal SCC based on improved disease-related outcomes, sphincter preservation and morbidity profiles. This conclusion is supported by a systematic literature review.

Comparison of neoadjuvant chemoradiotherapy and neoadjuvant chemotherapy for esophageal cancer: a meta-analysis

Aim: To compare the clinical efficacy of neoadjuvant chemoradiotherapy (nCRT) and neoadjuvant chemotherapy (nCT) for esophageal cancer. Methods: Randomized controlled trials reporting on the comparison of nCRT and nCT for esophageal cancer were identified. Results: Three eligible randomized controlled trials were identified and included with a total of 375 patients (189 nCRT, 186 nCT). Outcomes showed that compared with nCT group, R0 resection and pathologic complete response (pCR) rates were significantly increased in nCRT group. However, no significant difference was seen in 3- and 5-year progression-free survival or 3- and 5-year overall survival. Conclusion: The addition of radiotherapy to neoadjuvant chemotherapy results in higher R0 resection rate and pCR rate, without significantly impacting survival.

Hypofractionated Image-Guided Radiation Therapy With Simultaneous-Integrated Boost Technique for Limited Metastases: A Multi-Institutional Analysis

Purpose: To perform a multi-institutional analysis following treatment of limited osseous and/or nodal metastases in patients using a novel hypofractionated image-guided radiotherapy with simultaneous-integrated boost (HIGRT-SIB) technique.

Methods: Consecutive patients treated with HIGRT-SIB for ≤5 active metastases at Duke University Medical Center or Durham Veterans' Affairs Medical Center between 2013 and 2018 were analyzed to determine toxicities and recurrence patterns following treatment. Most patients received 50 Gy to the PTV_boost and 30 Gy to the PTV_elect simultaneously in 10 fractions. High-dose treatment volume recurrence (HDTVR) and low-dose treatment volume recurrence (LDTVR) were defined as recurrences within PTV_boost and PTV_elect, respectively. Marginal recurrence (MR) was defined as recurrence outside PTV_elect, but within the adjacent bone or nodal chain. Distant recurrence (DR) was defined as recurrences not meeting HDTVR, LDTVR, or MR criteria. Freedom from pain recurrence (FFPR) was calculated in patients with painful osseous metastases prior to HIGRT-SIB. Outcome rates were estimated at 12 months using the Kaplan-Meier method.

Results: Forty-two patients met inclusion criteria with 59 sites treated with HIGRT-SIB (53% nodal and 47% osseous). Median time from diagnosis to first metastasis was 31 months and the median age at HIGRT-SIB was 69 years. The most common primary tumors were prostate (36%), gastrointestinal (24%), and lung (24%). Median follow-up was 11 months. One acute grade ≥3 toxicity (febrile neutropenia) occurred after docetaxel administration immediately following HIGRT-SIB. Four patients developed late grade ≥3 toxicities: two ipsilateral vocal cord paralyzes and two vertebral compression fractures. The overall pain response rate was 94% and the estimated FFPR at 12 months was 72%. The estimated 12 month rate of HDTVR, LDTVR, MR, and DR was 3.6, 6.2, 7.6, and 55.8%, respectively. DR preceded MR, HDTVR, or LDTVR in each instance. The estimated 12 month probability of in-field and marginal control was 90.0%.

Conclusion: Targeting areas at high-risk for occult disease with a lower radiation dose, while simultaneously boosting gross disease with HIGRT in patients with limited osseous and/or nodal metastases, has a high rate of treated metastasis control, a low rate of MR, acceptable toxicity, and high rate of pain palliation. Further investigation with prospective trials is warranted.

Role of pelvic chemoradiation therapy in patients with initially metastatic anal canal cancer: A National Cancer Database review

BACKGROUND

Although the management of localized anal canal squamous cell carcinomas is well established, the role of pelvic chemoradiation (CRT) in the treatment of patients presenting with synchronous metastatic (stage IV) disease is poorly defined. This study used a national cancer database to compare the overall survival (OS) rates of patients with synchronous metastatic disease receiving CRT to the pelvis and patients treated with chemotherapy (CT) alone.

METHODS

This study included adult patients with anal canal squamous cell carcinomas presenting with synchronous metastases diagnosed from 2004 to 2012. Multiple imputation and 2:1 propensity score matching were used to create a matched data set for testing. The proportional hazards model was used to estimate the hazard ratio (HR) for the effect of the treatment group on OS. With only patients in the matched data set, the OS of the treatment groups was estimated with the Kaplan-Meier method by treatment group.

RESULTS

This study started with an unmatched data set of 978 patients, and 582 patients were selected for the matched data set: 388 in the CRT group and 194 in the CT-alone group. The HR for the group effect was 0.75 (95% confidence interval [CI], 0.61-0.92; P = .006). The median OS was 21.1 months in the CRT group (95% CI, 17.4-24.0 months) and 14.6 months in the CT group (95% CI, 12.2-18.4 months). The corresponding 5-year OS rates were 23% (95% CI, 18%-28%) and 14% (95% CI, 7%-21%), respectively.

CONCLUSIONS

In this large series analyzing OS in patients with stage IV anal cancer, CRT was associated with improved OS in comparison with CT alone. Because of the lack of prospective data in this setting, this evidence will help to guide treatment approaches in this group of patients.

Multi-institutional analysis of synchronous prostate and rectosigmoid cancers

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Background: Synchronous prostate cancer (PC) and rectosigmoid (RS) cancer (RSC) is a challenging clinical situation. Methods: A retrospective review of Duke University and Durham VA charts was performed for men with adenocarcinomas of the prostate and RS colon from 1988-2017. Synchronous presentation was defined as symptoms, diagnosis (dx), or treatment (tx) of PC/RSC within 12 months. The primary endpoint was overall survival (OS), calculated from latest dx date. Univariate and multivariate (MVA) Cox regression was performed using STATA 15.1. Results: Among 31,883 men with PC identified, 330 (1%) also had RSC. 54 (16%) were considered synchronous (median age 67, IQR 62-72). PC was more commonly the first dx (59%), and 15 (28%) underwent prostatectomy (n=13) or radiotherapy (RT, n=2) before a dx of synchronous RSC. 26%, 57%, and 17% had stage I, II-III, and IV RSC, respectively. Prostatectomy, LAR, APR, and combined surgery for both PC/RSC was performed in 17 (31%), 24 (44%), 10 (19%), and 2 (4%) men, respectively. 35 (65%) received RT with median RS dose of 50.4 Gy (IQR 50.4-54 Gy) and prostate boost to 66 Gy (IQR 61-72 Gy). 34 (63%) received 5-FU based chemotherapy, 23 (43%) received ADT, and 9 (17%) received no PC-specific tx. After a median follow up of 43 (IQR 21-93) months, there were 34 deaths: 18 (53%) due to RSC, 2 (6%) due to PC, 3 (9%) due to grade 5 toxicity, 7 (21%) due to another malignancy, and 4 (12%) due to unknown cause without recurrence. Grade 5 toxicities resulted from sequential hepatectomy/LAR, combined prostatectomy/APR, and myocardial infarction while on ADT. Crude late grade ≥3 toxicities include 9 (17%) GI and 6 (11%) GU. Two anastomotic leaks <2.3 years after LAR occurred in men who received neoadjuvant prostate RT boost of 70.6-76.4 Gy. Stages II-III (HR 4.3, p=0.02) and IV (HR 16, p<0.01) for RSC but only stage IV (HR 31, p<0.01) for PC were significantly associated with OS on MVA. Among 30 men with stage II-III RSC and non-metastatic PC, 5-FU based chemotherapy (HR 0.34, p=0.04) but no PC-specific tx was significantly associated with OS on MVA. Conclusions: Synchronous RSC is a greater contributor to mortality than PC. Men aged ≥50 with localized PC should undergo colorectal cancer screening prior to tx to evaluate for synchronous RSC.

Intratreatment Response Assessment With 18F-FDG PET: Correlation of Semiquantitative PET Features With Pathologic Response of Esophageal Cancer to Neoadjuvant Chemoradiotherapy

PURPOSE

This prospective study seeks to extract semiquantitative positron emission tomography (PET) features from 18F-fluorodeoxyglucose PET scans performed before and during neoadjuvant chemoradiotherapy for esophageal cancer and to compare their accuracy in predicting histopathologic response.

METHODS AND MATERIALS

From 2012 to 2016, 26 patients with esophageal cancer underwent pretreatment and intratreatment PET scans during chemoradiotherapy followed by surgery. Median patient age was 63 years (interquartile range, 58-68 years); 26 patients had esophageal adenocarcinoma, and 3 had esophageal squamous cell carcinoma. The intratreatment PET scan was performed at a median of 32.4 Gy (interquartile range, 30.6-32.4 Gy). PET features of the primary site including maximum standardized uptake value (SUV), SUV mean, metabolic tumor volume, and total lesion glycolysis were extracted from the pretreatment and intratreatment PET scans. Patients were histopathologic responders if there was complete or near-complete tumor response by modified Ryan scheme. Mean values of PET features were compared between histopathologic responders and nonresponders. The area under the receiver operating characteristic curve (AUC) was used to compare the accuracy of PET features in predicting histopathologic response.

RESULTS

Eleven patients (42%) were histopathologic responders. PET features most discriminatory of histopathologic response on AUC analysis were volumetric PET features from the intratreatment PET including metabolic tumor volume based on manual contour (AUC, 0.73; 95% confidence interval, 0.52-0.93) and total lesion glycolysis based on semiautomatic 40% SUV threshold (AUC, 0.73; 95% confidence interval, 0.53-0.94).

CONCLUSIONS

Volumetric PET features from the intratreatment PET were the most accurate predictors of histopathologic response.

The role of external beam radiotherapy in the treatment of hepatocellular cancer

Hepatocellular carcinoma (HCC) is increasing in incidence and mortality. Although the prognosis remains poor, long-term survival has improved from 3% in 1970 to an 18% 5-year survival rate today. This is likely because of the introduction of well tolerated, oral antiviral therapies for hepatitis C. Curative options for patients with HCC are often limited by underlying liver dysfunction/cirrhosis and medical comorbidities. Less than one-third of patients are candidates for surgery, which is the current gold standard for cure. Nonsurgical treatments include embolotherapies, percutaneous ablation, and ablative radiation. Technological advances in radiation delivery in the past several decades now allow for safe and effective ablative doses to the liver. Conformal techniques allow for both dose escalation to target volumes and normal tissue sparing. Multiple retrospective and prospective studies have demonstrated that hypofractionated image-guided radiation therapy, used as monotherapy or in combination with other liver-directed therapies, can provide excellent local control that is cost effective. Therefore, as the HCC treatment paradigm continues to evolve, ablative radiation treatment has moved from a palliative treatment to both a "bridge to transplant" and a definitive treatment.

Evolution and Management of Treatment-Related Toxicity in Anal Cancer

Over the past several decades, clinical trials have demonstrated improved disease-related outcomes in the definitive treatment of anal cancer. Although treatment with radiation and concurrent chemotherapy results in high rates of cure, significant acute and late toxicities are seen. This review focuses on the evolution of treatment-related toxicity for anal cancer. Management of these adverse effects is reviewed, as are future directions in anal cancer treatment and their impact on toxicity.

Association between neoadjuvant chemoradiation and survival for patients with locally advanced rectal cancer

AIM

To examine the overall survival differences for the following neoadjuvant therapy modalities - no therapy, chemotherapy alone, radiation alone and chemoradiation - in a large cohort of patients with locally advanced rectal cancer.

METHOD

Adults with clinical Stage II and III rectal adenocarcinoma were selected from the National Cancer Database and grouped by type of neoadjuvant therapy received: no therapy, chemotherapy only, radiotherapy only or chemoradiation. Multivariable regression methods were used to compare adjusted differences in perioperative outcomes and overall survival.

RESULTS

Among 32 978 patients included, 9714 (29.5%) received no neoadjuvant therapy, 890 (2.7%) chemotherapy only, 1170 (3.5%) radiotherapy only and 21 204 (64.3%) chemoradiation. Compared with no therapy, chemotherapy or radiotherapy alone were not associated with any adjusted differences in surgical margin positivity, permanent colostomy rate or overall survival (all P > 0.05). With adjustment, neoadjuvant chemoradiation vs no therapy was associated with a lower likelihood of surgical margin positivity (OR 0.74, P < 0.001), decreased rate of permanent colostomy (OR 0.77, P < 0.001) and overall survival [hazard ratio (HR) 0.79, P < 0.001]. When compared with chemotherapy or radiotherapy alone, chemoradiation remained associated with improved overall survival (vs chemotherapy alone HR 0.83, P = 0.04; vs radiotherapy alone HR 0.83, P < 0.019).

CONCLUSION

Neoadjuvant chemoradiation, not chemotherapy or radiotherapy alone, is important for sphincter preservation, R0 resection and survival for patients with locally advanced rectal cancer. Despite this finding, one-third of patients in the United States with locally advanced rectal cancer fail to receive stage-appropriate chemoradiation.

Association Between Incomplete Neoadjuvant Radiotherapy and Survival for Patients With Locally Advanced Rectal Cancer

Importance

Failing to complete chemotherapy adversely affects survival in patients with colorectal cancer. However, the effect of incomplete delivery of neoadjuvant radiotherapy is unclear.

Objective

To determine whether incomplete radiotherapy delivery is associated with worse clinical outcomes and survival.

Design, Setting, and Participants

Data on 17 600 patients with stage II to III rectal adenocarcinoma from the 2006-2012 National Cancer Database who received neoadjuvant chemoradiotherapy followed by surgical resection were included. Multivariable regression methods were used to compare resection margin positivity, permanent colostomy rate, 30-day readmission, 90-day mortality, and overall survival between patients who received complete (45.0-50.4 Gy) and incomplete (<45.0 Gy) doses of radiation as preoperative therapy.

Main Outcomes and Measures

The primary outcome measure was overall survival; short-term perioperative and oncologic outcomes encompassing margin positivity, permanent ostomy rate, postoperative readmission, and postoperative mortality were also assessed.

Results

Among 17 600 patients included, 10 862 were men, with an overall median age of 59 years (range, 51-68 years). Of these, 874 patients (5.0%) received incomplete doses of neoadjuvant radiation. The median radiation dose received among those who did not achieve complete dosing was 34.2 Gy (interquartile range, 19.8-40.0 Gy). Female sex (adjusted odds ratio [OR] 0.69; 95% CI, 0.59-0.81; P < .001) and receiving radiotherapy at a different hospital than the one where surgery was performed (OR, 0.72; 95% CI, 0.62-0.85; P < .001) were independent predictors of failing to achieve complete dosing; private insurance status was predictive of completing radiotherapy (OR, 1.60; 95% CI, 1.16-2.21; P = .004). At 5-year follow-up, overall survival was improved among patients who received a complete course of radiotherapy (3086 [estimated survival probability, 73.2%] vs 133 [63.0%]; P < .001). After adjustment for demographic, clinical, and tumor characteristics, patients receiving a complete vs incomplete radiation dose had a similar resection margin positivity (OR, 0.99; 95% CI, 0.72-1.35; P = .92), permanent colostomy rate (OR, 0.96; 95% CI, 0.70-1.32; P = .81), 30-day readmission rate (OR, 0.92; 95% CI, 0.67-1.27; P = .62), and 90-day mortality (OR, 0.72; 95% CI, 0.33-1.54; P = .41). However, a complete radiation dose had a significantly lower risk of long-term mortality (adjusted hazard ratio, 0.70; 95% CI, 0.59-0.84; P < .001).

Conclusions and Relevance

Achieving a target radiation dose of 45.0 to 50.4 Gy is associated with a survival benefit in patients with locally advanced rectal cancer. Aligning all aspects of multimodal oncology care may increase the probability of completing neoadjuvant therapy.

Retrospective four-dimensional magnetic resonance imaging with image-based respiratory surrogate: a sagittal-coronal-diaphragm point of intersection motion tracking method

A four-dimensional magnetic resonance imaging (4-D-MRI) technique with Sagittal-Coronal-Diaphragm Point-of-Intersection (SCD-PoI) as a respiratory surrogate is proposed. To develop an image-based respiratory surrogate, the SCD-PoI motion tracking method is used for retrospective 4-D-MRI reconstruction. Single-slice sagittal MR cine was acquired at a location near the center of the diaphragmatic dome. Multiple-slice coronal MR cines were acquired for 4-D-MRI reconstruction. As a motion surrogate, the diaphragm motion was measured from the PoI among the sagittal MRI cine plane, coronal MRI cine planes, and the diaphragm surface. These points were defined as the SCD-PoI. This point is used as a one-dimensional diaphragmatic navigator in our study. The 4-D-MRI technique was evaluated on a 4-D digital extended cardiac-torso (XCAT) human phantom, a motion phantom, and seven human subjects (five healthy volunteers and two cancer patients). Motion trajectories of a selected region of interest were measured on 4-D-MRI and compared with the known XCAT motion that served as references. The mean absolute amplitude difference ([Formula: see text]) and the cross-correlation coefficient (CC) of the comparisons were determined. 4-D-MRI of the XCAT phantom demonstrated highly accurate motion information ([Formula: see text], [Formula: see text]). Motion trajectories of the motion phantom measured on 4-D-MRI matched well with the references ([Formula: see text], [Formula: see text]). 4-D-MRI of human subjects showed minimal artifacts and clearly revealed the respiratory motion of organs and tumor (mean [Formula: see text]; mean [Formula: see text]). A 4-D-MRI technique with image-based respiratory surrogate has been developed and tested on phantoms and human subjects.

Total neoadjuvant therapy for rectal cancer: An emerging option

The treatment of locally advanced rectal cancer (LARC) has benefited from improved surgical techniques and from the implementation of neoadjuvant chemoradiotherapy (CRT), which have markedly decreased the rates of local recurrence. However, distant metastatic disease remains the most significant cause of death for these patients. Although adjuvant chemotherapy (ChT) after neoadjuvant CRT and definitive surgery is commonly recommended, the value of adjuvant systemic therapy remains less clear. Trials evaluating adjuvant ChT for rectal cancer have been handicapped by poor compliance rates and inconsistent survival results. Shifting systemic therapy delivery to the neoadjuvant setting has the promise to improve compliance rates, reduce toxicity, and decrease distant relapse rates. Recently, multiple prospective trials have reported on the use of total neoadjuvant therapy (TNT) for patients with LARC, incorporating both ChT and CRT in the neoadjuvant setting. Here, the authors review the promising results from those trials. Because the studies have largely focused on pathologic outcomes (primarily pathologic complete response rates), ongoing phase 2 and 3 trials are now underway assessing the long-term disease-related outcomes with TNT. In addition to improving survival, TNT has the potential to increase the pool of patients with LARC who are eligible for organ preservation, which is also being evaluated. Cancer 2017;123:1497-1506. © 2017 American Cancer Society.

Interim FDG-PET imaging during neoadjuvant chemoradiotherapy for esophageal cancer: Correlation with pathologic response

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Background: In this prospective study we evaluated whether changes in metabolic tumor parameters on interim flurodeoxyglucose positron emission tomography (FDG-PET) performed during neoadjuvant chemoradiotherapy (CRT) for esophageal cancer correlates with histopathologic tumor response. Methods: From February 2012 to February 2016, 60 patients with esophageal cancer underwent PET scans before therapy and after 30-36 Gy. Patients who underwent surgery after carboplatin/paclitaxel CRT were eligible for the current analysis. PET metrics of the primary site including maximum standardized uptake value (SUVmax), SUV mean, metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were extracted from the pre-treatment and interim PET based on a manual contour and SUV 2.5 threshold. Patients were called histopathologic responders if they had a complete or near complete tumor response based on the modified Ryan scheme. Relative changes in PET metrics between pre-treatment and interim PET were compared between histopathologic responders and non-responders using the Mann-Whitney test and binary logistic regression. Results: Twenty-six patients were included in the analysis. Adenocarcinoma was the most common histology (n = 23). Eleven patients (42%) had a complete or near complete pathologic response to CRT (histopathologic responders). Changes in PET metrics from pre-treatment to interim PET based on the manual contour were not significantly different between responding and nonresponding tumors. The relative reduction of SUVmax (Mean ± SD) was 38.2% ± 28.4% for histopathologic responders and 27.9% ± 31.4% for non-responders. The relative reduction in MTV, SUV mean and TLG was 36.1% ± 26.2%, 23.5% ± 21.3%, and 49.3% ± 28.3% for histopathologic responders and 28.6% ± 32.0%, 11.8% ± 19.1%, and 33.1% ± 38.5% for histopathologic non-responders, respectively. When analyzed based on the SUV 2.5 threshold there continued to be no significant difference in PET metrics. Conclusions: In this pilot study we observed changes in metabolic tumor parameters on PET performed during CRT for esophageal cancer. However, these changes did not predict for histopathologic responders.

Four-dimensional diffusion-weighted MR imaging (4D-DWI): a feasibility study

PURPOSE

Diffusion-weighted Magnetic Resonance Imaging (DWI) has been shown to be a powerful tool for cancer detection with high tumor-to-tissue contrast. This study aims to investigate the feasibility of developing a four-dimensional DWI technique (4D-DWI) for imaging respiratory motion for radiation therapy applications.

MATERIALS/METHODS

Image acquisition was performed by repeatedly imaging a volume of interest (VOI) using an interleaved multislice single-shot echo-planar imaging (EPI) 2D-DWI sequence in the axial plane. Each 2D-DWI image was acquired with an intermediately low b-value (b = 500 s/mm² ) and with diffusion-encoding gradients in x, y, and z diffusion directions. Respiratory motion was simultaneously recorded using a respiratory bellow, and the synchronized respiratory signal was used to retrospectively sort the 2D images to generate 4D-DWI. Cine MRI using steady-state free precession was also acquired as a motion reference. As a preliminary feasibility study, this technique was implemented on a 4D digital human phantom (XCAT) with a simulated pancreas tumor. The respiratory motion of the phantom was controlled by regular sinusoidal motion profile. 4D-DWI tumor motion trajectories were extracted and compared with the input breathing curve. The mean absolute amplitude differences (D) were calculated in superior-inferior (SI) direction and anterior-posterior (AP) direction. The technique was then evaluated on two healthy volunteers. Finally, the effects of 4D-DWI on apparent diffusion coefficient (ADC) measurements were investigated for hypothetical heterogeneous tumors via simulations.

RESULTS

Tumor trajectories extracted from XCAT 4D-DWI were consistent with the input signal: the average D value was 1.9 mm (SI) and 0.4 mm (AP). The average D value was 2.6 mm (SI) and 1.7 mm (AP) for the two healthy volunteers.

CONCLUSION

A 4D-DWI technique has been developed and evaluated on digital phantom and human subjects. 4D-DWI can lead to more accurate respiratory motion measurement. This has a great potential to improve the visualization and delineation of cancer tumors for radiotherapy.

A current perspective on stereotactic body radiation therapy for pancreatic cancer

Pancreatic cancer is a formidable malignancy with poor outcomes. The majority of patients are unable to undergo resection, which remains the only potentially curative treatment option. The management of locally advanced (unresectable) pancreatic cancer is controversial; however, treatment with either chemotherapy or chemoradiation is associated with high rates of local tumor progression and metastases development, resulting in low survival rates. An emerging local modality is stereotactic body radiation therapy (SBRT), which uses image-guided, conformal, high-dose radiation. SBRT has demonstrated promising local control rates and resultant quality of life with acceptable rates of toxicity. Over the past decade, increasing clinical experience and data have supported SBRT as a local treatment modality. Nevertheless, additional research is required to further evaluate the role of SBRT and improve upon the persistently poor outcomes associated with pancreatic cancer. This review discusses the existing clinical experience and technical implementation of SBRT for pancreatic cancer and highlights the directions for ongoing and future studies.

Radiation Therapy for Soft Tissue Sarcoma: Indications and Controversies for Neoadjuvant Therapy, Adjuvant Therapy, Intraoperative Radiation Therapy, and Brachytherapy

Soft tissue sarcomas are rare mesenchymal cancers that pose a treatment challenge. Although small superficial soft tissue sarcomas can be managed by surgery alone, adjuvant radiotherapy in addition to limb-sparing surgery substantially increases local control of extremity sarcomas. Compared with postoperative radiotherapy, preoperative radiotherapy doubles the risk of a wound complication, but decreases the risk for late effects, which are generally irreversible. For retroperitoneal sarcomas, intraoperative radiotherapy can be used to safely escalate the radiation dose to the tumor bed. Patients with newly diagnosed sarcoma should be evaluated before surgery by a multidisciplinary team that includes a radiation oncologist.

Effect of combined neoadjuvant chemoradiation on overall survival for patients with locally advanced rectal cancer

657

Background: Prospective randomized trials have demonstrated that neoadjuvant chemoradiation improves local control and results in a higher rate of sphincter-sparing surgery for patients with locally advanced rectal cancer. However, neoadjuvant therapy utilization and population-based outcomes are not well defined. Methods: Adults with stage II/III rectal adenocarcinoma within the National Cancer Data Base undergoing surgery between 2006-2012 were analyzed. Patients were grouped by type of neoadjuvant therapy received: no therapy, chemotherapy only, radiotherapy only, or concomitant chemoradiation. Multivariable modeling was used to compare perioperative outcomes and overall survival between groups. Results: Among 32,978 patients included, 9,714 (29.5%) received no neoadjuvant therapy, 890 (2.7%) chemotherapy only, 1,170 (3.5%) radiotherapy only, and 21,204 (64.3%) concomitant chemoradiation. 5-year overall survival among groups was 62%, 69%, 71%, and 74%, respectively. Compared to no therapy, chemotherapy or radiotherapy alone was not associated with any differences in perioperative or oncologic outcomes (all p > 0.05). With adjustment for patient and disease characteristics, neoadjuvant chemoradiation was associated with a lower likelihood of margin positivity (OR 0.74, p < 0.001), need for permanent colostomy (OR 0.77, 95% CI 0.70-0.85, p < 0.001), 30-day mortality (OR 0.67, p = 0.003), and overall survival (HR 0.69, p < 0.001). When compared to chemotherapy or radiotherapy alone, neoadjuvant chemoradiation was still associated with improved overall survival (vs. chemotherapy: HR 0.83, p = 0.04; vs. radiotherapy: HR 0.75, p < 0.001). Conclusions: Neoadjuvant chemoradiation, not chemotherapy or radiotherapy alone, is important for sphincter-preservation and survival for patients with locally advanced rectal cancer. Despite this finding, one third of patients with locally advanced rectal cancer are failing to receive this therapy in the United States.

Evaluation of Adjuvant Radiation Therapy for Resected Gallbladder Carcinoma: A Multi-institutional Experience

PURPOSE

The role of adjuvant radiation for gallbladder carcinoma (GBC) is uncertain. We combine the experience of six National Cancer Institute-designated cancer centers to explore the impact of adjuvant radiation following oncologic resection of GBC.

METHODS

Patients who underwent extended surgery for GBC at Johns Hopkins, Mayo Clinic, Duke University, Oregon Health & Science University, University of Michigan, and University of Texas MD Anderson between 1985 and 2008 were reviewed. Patients with metastatic disease at surgery, gross residual disease, or missing pathologic information were excluded.

RESULTS

Of the 112 patients identified, 61 % received adjuvant radiation, 93 % of whom received concurrent chemotherapy. Median follow-up of surviving patients was 47.3 (range 2.2-167.7) months. Patients who received adjuvant radiation had a higher rate of advanced T-stage (57 vs. 16 %, p < 0.01), lymph node involvement (63 vs. 18 %, p < 0.01), and positive microscopic margins (37 vs. 9 %, p < 0.01) compared with patients managed with surgery alone, but overall survival (OS) was comparable between the two cohorts (5-year OS: 49.7 vs. 52.5 %, p = 0.20). Lymph node involvement had the strongest association with poor OS (p < 0.01). Adjuvant radiation was associated with decreased isolated local failure (hazard ratio 0.17, 95 % confidence interval 0.05-0.63, p = 0.01). However, 71 % of recurrences included distant failure.

CONCLUSIONS

Following oncologic resection for GBC, adjuvant radiation may offer improved local control compared with observation. The benefit of adjuvant radiation beyond chemotherapy alone should therefore be explored. Certainly, the high rate of distant failure highlights the need for more effective systemic therapy.

T2-weighted four dimensional magnetic resonance imaging with result-driven phase sorting

PURPOSE

T2-weighted MRI provides excellent tumor-to-tissue contrast for target volume delineation in radiation therapy treatment planning. This study aims at developing a novel T2-weighted retrospective four dimensional magnetic resonance imaging (4D-MRI) phase sorting technique for imaging organ/tumor respiratory motion.

METHODS

A 2D fast T2-weighted half-Fourier acquisition single-shot turbo spin-echo MR sequence was used for image acquisition of 4D-MRI, with a frame rate of 2-3 frames/s. Respiratory motion was measured using an external breathing monitoring device. A phase sorting method was developed to sort the images by their corresponding respiratory phases. Besides, a result-driven strategy was applied to effectively utilize redundant images in the case when multiple images were allocated to a bin. This strategy, selecting the image with minimal amplitude error, will generate the most representative 4D-MRI. Since we are using a different image acquisition mode for 4D imaging (the sequential image acquisition scheme) with the conventionally used cine or helical image acquisition scheme, the 4D dataset sufficient condition was not obviously and directly predictable. An important challenge of the proposed technique was to determine the number of repeated scans (NR) required to obtain sufficient phase information at each slice position. To tackle this challenge, the authors first conducted computer simulations using real-time position management respiratory signals of the 29 cancer patients under an IRB-approved retrospective study to derive the relationships between NR and the following factors: number of slices (NS), number of 4D-MRI respiratory bins (NB), and starting phase at image acquisition (P0). To validate the authors' technique, 4D-MRI acquisition and reconstruction were simulated on a 4D digital extended cardiac-torso (XCAT) human phantom using simulation derived parameters. Twelve healthy volunteers were involved in an IRB-approved study to investigate the feasibility of this technique.

RESULTS

4D data acquisition completeness (Cp) increases as NR increases in an inverse-exponential fashion (Cp = 100 - 99 × exp(-0.18 × NR), when NB = 6, fitted using 29 patients' data). The NR required for 4D-MRI reconstruction (defined as achieving 95% completeness, Cp = 95%, NR = NR,95) is proportional to NB (NR,95 ∼ 2.86 × NB, r = 1.0), but independent of NS and P0. Simulated XCAT 4D-MRI showed a clear pattern of respiratory motion. Tumor motion trajectories measured on 4D-MRI were comparable to the average input signal, with a mean relative amplitude error of 2.7% ± 2.9%. Reconstructed 4D-MRI for healthy volunteers illustrated clear respiratory motion on three orthogonal planes, with minimal image artifacts. The artifacts were presumably caused by breathing irregularity and incompleteness of data acquisition (95% acquired only). The mean relative amplitude error between critical structure trajectory and average breathing curve for 12 healthy volunteers is 2.5 ± 0.3 mm in superior-inferior direction.

CONCLUSIONS

A novel T2-weighted retrospective phase sorting 4D-MRI technique has been developed and successfully applied on digital phantom and healthy volunteers.

Neoadjuvant radiation therapy does not increase perioperative morbidity among patients undergoing gastrectomy for gastric cancer

BACKGROUND

Neoadjuvant radiation therapy (RT) as a component of the multimodality treatment of gastric cancer has demonstrated promising results. Data regarding its effect on perioperative safety are limited.

METHODS

Adults undergoing gastrectomy for gastric cancer in the 2005-2011 National Surgical Quality Improvement Program were included. Groups were defined by neoadjuvant RT use, and then propensity-matched based on preoperative variables. Multivariable logistic regression was performed to assess neoadjuvant RT as an independent predictor of outcomes.

RESULTS

Among 2,764 patients identified, 55 (2.0%) were treated with neoadjuvant RT. Patients who received neoadjuvant RT were more likely to have received preoperative chemotherapy and steroids, and experienced weight loss (all P < 0.01). After matching, however, there were no preoperative differences. At time of surgery, total (vs. partial) gastrectomy was more common among patients who underwent neoadjuvant RT (70.9 vs. 46.7%, P < 0.01), and operative time was longer (290 vs. 236 min, P < 0.01). There were no differences in overall complications (23.6 vs. 29.7%, P = 0.49) or 30-day mortality (3.6 vs. 3.6%, P = 0.99).

CONCLUSIONS

Neoadjuvant RT was not associated with increased morbidity or mortality following resection for gastric cancer. These findings support the ongoing investigation of neoadjuvant RT as part of the multidisciplinary management of resectable gastric cancer.

Investigation of sagittal image acquisition for 4D-MRI with body area as respiratory surrogate

PURPOSE

The authors have recently developed a novel 4D-MRI technique for imaging organ respiratory motion employing cine acquisition in the axial plane and using body area (BA) as a respiratory surrogate. A potential disadvantage associated with axial image acquisition is the space-dependent phase shift in the superior-inferior (SI) direction, i.e., different axial slice positions reach the respiratory peak at different respiratory phases. Since respiratory motion occurs mostly in the SI and anterior-posterior (AP) directions, sagittal image acquisition, which embeds motion information in these two directions, is expected to be more robust and less affected by phase-shift than axial image acquisition. This study aims to develop and evaluate a 4D-MRI technique using sagittal image acquisition.

METHODS

The authors evaluated axial BA and sagittal BA using both 4D-CT images (11 cancer patients) and cine MR images (6 healthy volunteers and 1 cancer patient) by comparing their corresponding space-dependent phase-shift in the SI direction (δSPS (SI)) and in the lateral direction (δSPS (LAT)), respectively. To evaluate sagittal BA 4D-MRI method, a motion phantom study and a digital phantom study were performed. Additionally, six patients who had cancer(s) in the liver were prospectively enrolled in this study. For each patient, multislice sagittal MR images were acquired for 4D-MRI reconstruction. 4D retrospective sorting was performed based on respiratory phases. Single-slice cine MRI was also acquired in the axial, coronal, and sagittal planes across the tumor center from which tumor motion trajectories in the SI, AP, and medial-lateral (ML) directions were extracted and used as references from comparison. All MR images were acquired in a 1.5 T scanner using a steady-state precession sequence (frame rate ∼ 3 frames/s).

RESULTS

4D-CT scans showed that δSPS (SI) was significantly greater than δSPS (LAT) (p-value: 0.012); the median phase-shift was 16.9% and 7.7%, respectively. Body surface motion measurement from axial and sagittal MR cines also showed δSPS (SI) was significantly greater than δSPS (LAT). The median δSPS (SI) and δSPS (LAT) was 11.0% and 9.2% (p-value = 0.008), respectively. Tumor motion trajectories from 4D-MRI matched with those from single-slice cine MRI: the mean (±SD) absolute differences in tumor motion amplitude between the two were 1.5 ± 1.6 mm, 2.1 ± 1.9 mm, and 1.1 ± 1.0 mm in the SI, ML, and AP directions from this patient study.

CONCLUSIONS

Space-dependent phase shift is less problematic for sagittal acquisition than for axial acquisition. 4D-MRI using sagittal acquisition was successfully carried out in patients with hepatic tumors.

Human papillomavirus tumor infection in esophageal squamous cell carcinoma

The association between human papillomavirus (HPV) and esophageal squamous cell carcinoma (ESCC) has been recognized for over three decades. Recently, multiple meta-analyses have drawn upon existing literature to assess the strength of the HPV-ESCC linkage. Here, we review these analyses and attempt to provide a clinically-relevant overview of HPV infection in ESCC. HPV-ESCC detection rates are highly variable across studies. Geographic location likely accounts for a majority of the variation in HPV prevalence, with high-incidence regions including Asia reporting significantly higher HPV-ESCC infection rates compared with low-incidence regions such as Europe, North America, and Oceania. Based on our examination of existing data, the current literature does not support the notion that HPV is a prominent carcinogen in ESCC. We conclude that there is no basis to change the current clinical approach to ESCC patients with respect to tumor HPV status.

The safety and tolerability of veliparib (V) plus capecitabine (C) and radiation (RT) in subjects with locally advanced rectal cancer (LARC): Results of a phase 1b study

579

Background: Patients (pts) with LARC treated with neoadjuvant C/RT and then surgery have low rates of pathologic complete response (ypCR) and significant relapse rates. V is a potent, orally bioavailable PARP inhibitor that has been shown to enhance the efficacy of chemotherapy and RT in preclinical models. This study sought to establish the recommended phase 2 dose (RPTD), as well as to assess safety, pharmacokinetics (PK), and preliminary activity of V + RT/C in pts with LARC. Methods: Pts with stage II-III rectal cancer received RT (50.4Gy/1.8Gy/fraction) with C (825 mg/m2 BID) five days per week (W) for 5.5W. Dosing of V (BID, 20mg-400mg) continued from W1D2 to 2 days past RT. Pts underwent surgery 5-10W following RT. Assessments included identification of RPTD with the Exposure Adjusted Continual Reassessment Method, adverse events (AEs), PK, and pathological response (ypCR and tumor downstaging rates). Results: As of August 5, 2014, 30 pts have been enrolled, 24/6 male/female, median age 58 yrs; 1 pt discontinued due to an AE. The most common treatment-emergent AEs possibly or probably related to V (>15% pts, n >4) were nausea (40%), fatigue (37%), diarrhea (30%), vomiting (20%), and dysgeusia (17%). One grade 3/4 event each of anemia and lymphopenia and 2 grade 3/4 events of diarrhea were deemed at least possibly related to V. Two dose limiting toxicities (DLTs) occurred: 1 at 70 mg BID V (radiation skin injury requiring dose interruption); 1 at 400 mg BID (nausea and vomiting requiring discontinuation). The RPTD is 400 mg BID of V in combination with RT/C. PK results from 16 pts suggest that V PK was approximately dose proportional when administered with RT/C and that V had no effect on the PK of C. To date, 18/25 (72%) pts have been downstaged post-surgery; with 7/25 (28%) achieving ypCR. Conclusions: V at 400 mg in combination with RT/C has an acceptable safety profile. 72% of 25 evaluable patients had tumor downstaging post-surgery, including 28% with ypCR. Dose escalation of V resulted in approximately dose-proportional increases in the V PK with no clear effect on C PK. Clinical trial information: NCT01589419.

Patterns of failure for stage I ampulla of Vater adenocarcinoma: a single institutional experience

BACKGROUND

Ampullary adenocarcinoma is a rare malignancy associated with a relatively favorable prognosis. Given high survival rates in stage I patients reported in small series with surgery alone, adjuvant chemoradiotherapy (CRT) has traditionally been recommended only for patients with high risk disease. Recent population-based data have demonstrated inferior outcomes to previous series. We examined disease-related outcomes for stage I tumors treated with pancreaticoduodenectomy, with and without CRT.

METHODS

All patients with stage I ampullary adenocarcinoma treated from 1976 to 2011 at Duke University were reviewed. Disease-related endpoints including local control (LC), metastasis-free survival (MFS), disease-free survival (DFS) and overall survival (OS) were analyzed using the Kaplan-Meier method.

RESULTS

Forty-four patients were included in this study. Thirty-one patients underwent surgery alone, while 13 also received adjuvant CRT. Five-year LC, MFS, DFS and OS for patients treated with surgery only and surgery with CRT were 56% and 83% (P=0.13), 67% and 83% (P=0.31), 56% and 83% (P=0.13), and 53% and 68% (P=0.09), respectively.

CONCLUSIONS

The prognosis for patients diagnosed with stage I ampullary adenocarcinoma may not be as favorable as previously described. Our data suggests a possible benefit of adjuvant CRT delivery.

Incidence and prognostic impact of high-risk HPV tumor infection in cervical esophageal carcinoma

BACKGROUND

Cervical esophageal carcinoma (CEC) is an uncommon malignancy. Limited data supports the use of definitive chemoradiotherapy (CRT) as primary treatment. Furthermore, the role of human papillomavirus (HPV) tumor infection in CEC remains unknown. This study retrospectively analyzes both outcomes of CEC patients treated with CRT and the incidence and potential role of HPV tumor infection in CEC lesions.

METHODS

A total of 37 CEC patients were treated with definitive CRT at our institution between 1987 and 2013. Of these, 19 had tumor samples available for high-risk HPV (types 16 and 18) pathological analysis.

RESULTS

For all patients (n=37), 5-year overall survival (OS), disease-free survival (DFS), and loco-regional control (LRC) rates were 34.1%, 40.2%, and 65.6%, respectively. On pathological analysis, 1/19 (5.3%) patients had an HPV-positive lesion.

CONCLUSIONS

Definitive CRT provides disease-related outcomes comparable to surgery. Moreover, HPV tumor infection in CEC is uncommon and its prognostic role is unclear. Our data contribute to the construction of an anatomical map of HPV tumor infection in squamous cell carcinomas (SCC) of the upper aerodigestive tract, and suggest a steep drop in viral infection rates at sites distal to the oropharynx, including the cervical esophagus.

Radiosensitive orbital metastasis as presentation of occult colonic adenocarcinoma

An 82-year-old man presented with progressive right frontal headaches. The patient's history was significant for benign polyps on surveillance colonoscopy 2 years prior, without high-grade dysplasia or carcinoma. MRI revealed an enhancing lesion arising within the superomedial aspect of the right orbit. Lesion biopsy demonstrated histological appearance and immunophenotype suggestive of colonic adenocarcinoma. Staging positron emission tomography/CT showed visceral metastases and diffuse activity in the posterior rectosigmoid, consistent with metastatic colon cancer. Treatment of the orbital lesion with external beam radiotherapy to 30 Gy resulted in significant palliation of the patient's headaches. The patient expired 2 months following treatment completion due to disease progression. Orbital metastasis as the initial presentation of an occult colorectal primary lesion is exceedingly rare, and occurred in this patient despite surveillance colonoscopy. Radiotherapy remains an efficacious modality for treatment of orbital metastases.

Is diaphragm motion a good surrogate for liver tumor motion?

PURPOSE

To evaluate the relationship between liver tumor motion and diaphragm motion.

METHODS AND MATERIALS

Fourteen patients with hepatocellular carcinoma (10 of 14) or liver metastases (4 of 14) undergoing radiation therapy were included in this study. All patients underwent single-slice cine-magnetic resonance imaging simulations across the center of the tumor in 3 orthogonal planes. Tumor and diaphragm motion trajectories in the superior-inferior (SI), anterior-posterior (AP), and medial-lateral (ML) directions were obtained using an in-house-developed normalized cross-correlation-based tracking technique. Agreement between the tumor and diaphragm motion was assessed by calculating phase difference percentage, intraclass correlation coefficient, and Bland-Altman analysis (Diff). The distance between the tumor and tracked diaphragm area was analyzed to understand its impact on the correlation between the 2 motions.

RESULTS

Of all patients, the mean (±standard deviation) phase difference percentage values were 7.1% ± 1.1%, 4.5% ± 0.5%, and 17.5% ± 4.5% in the SI, AP, and ML directions, respectively. The mean intraclass correlation coefficient values were 0.98 ± 0.02, 0.97 ± 0.02, and 0.08 ± 0.06 in the SI, AP, and ML directions, respectively. The mean Diff values were 2.8 ± 1.4 mm, 2.4 ± 1.1 mm, and 2.2 ± 0.5 mm in the SI, AP, and ML directions, respectively. Tumor and diaphragm motions had high concordance when the distance between the tumor and tracked diaphragm area was small.

CONCLUSIONS

This study showed that liver tumor motion had good correlation with diaphragm motion in the SI and AP directions, indicating diaphragm motion in the SI and AP directions could potentially be used as a reliable surrogate for liver tumor motion.

Patterns of recurrence after trimodality therapy for esophageal cancer

BACKGROUND

Patterns of failure after neoadjuvant chemoradiotherapy and surgery for esophageal cancer are poorly defined.

METHODS

All patients in the current study were treated with trimodality therapy for nonmetastatic esophageal cancer from 1995 to 2009. Locoregional failure included lymph node failure (NF), anastomotic failure, or both. Abdominal paraaortic failure (PAF) was defined as disease recurrence at or below the superior mesenteric artery.

RESULTS

Among 155 patients, the primary tumor location was the upper/middle esophagus in 18%, the lower esophagus in 32%, and the gastroesophageal junction in 50% (adenocarcinoma in 79% and squamous cell carcinoma in 21%) of patients. Staging methods included endoscopic ultrasound (73%), computed tomography (46%), and positron emission tomography/computed tomography (54%). Approximately 40% of patients had American Joint Committee on Cancer stage II disease and 60% had stage III disease. The median follow-up was 1.3 years. The 2-year locoregional control, event-free survival, and overall survival rates were 86%, 36%, and 48%, respectively. The 2-year NF rate was 14%, the isolated NF rate was 3%, and the anastomotic failure rate was 6%. The 2-year PAF rate was 9% and the isolated PAF rate was 5%. PAF was found to be increased among patients with gastroesophageal junction tumors (12% vs 6%), especially for the subset with ≥ 2 clinically involved lymph nodes at the time of diagnosis (19% vs 4%).

CONCLUSIONS

Few patients experience isolated NF or PAF as their first disease recurrence. Therefore, it is unlikely that targeting additional regional lymph node basins with radiotherapy would significantly improve clinical outcomes.

Four-dimensional magnetic resonance imaging using axial body area as respiratory surrogate: initial patient results

PURPOSE

To evaluate the feasibility of a retrospective binning technique for 4-dimensional magnetic resonance imaging (4D-MRI) using body area (BA) as a respiratory surrogate.

METHODS AND MATERIALS

Seven patients with hepatocellular carcinoma (4 of 7) or liver metastases (3 of 7) were enrolled in an institutional review board-approved prospective study. All patients were simulated with both computed tomography (CT) and MRI to acquire 3-dimensional and 4D images for treatment planning. Multiple-slice multiple-phase cine-MR images were acquired in the axial plane for 4D-MRI reconstruction. Image acquisition time per slice was set to 10-15 seconds. Single-slice 2-dimensional cine-MR images were also acquired across the center of the tumor in orthogonal planes. Tumor motion trajectories from 4D-MRI, cine-MRI, and 4D-CT were analyzed in the superior-inferior (SI), anterior-posterior (AP), and medial-lateral (ML) directions, respectively. Their correlation coefficients (CC) and differences in tumor motion amplitude were determined. Tumor-to-liver contrast-to-noise ratio (CNR) was measured and compared between 4D-CT, 4D-MRI, and conventional T2-weighted fast spin echo MRI.

RESULTS

The means (± standard deviations) of CC comparing 4D-MRI with cine-MRI were 0.97 ± 0.03, 0.97 ± 0.02, and 0.99 ± 0.04 in SI, AP, and ML directions, respectively. The mean differences were 0.61 ± 0.17 mm, 0.32 ± 0.17 mm, and 0.14 ± 0.06 mm in SI, AP, and ML directions, respectively. The means of CC comparing 4D-MRI and 4D-CT were 0.95 ± 0.02, 0.94 ± 0.02, and 0.96 ± 0.02 in SI, AP, and ML directions, respectively. The mean differences were 0.74 ± 0.02 mm, 0.33 ± 0.13 mm, and 0.18 ± 0.07 mm in SI, AP, and ML directions, respectively. The mean tumor-to-tissue CNRs were 2.94 ± 1.51, 19.44 ± 14.63, and 39.47 ± 20.81 in 4D-CT, 4D-MRI, and T2-weighted MRI, respectively.

CONCLUSIONS

The preliminary evaluation of our 4D-MRI technique results in oncologic patients demonstrates its potential usefulness to accurately measure tumor respiratory motion with improved tumor CNR compared with 4D-CT.