Analysis of the fecal metagenome in long-term survivors of pancreas cancer.

BACKGROUND: The 5-year overall survival of pancreas adenocarcinoma (PCa) remains less than 10%. Clinical and tumor genomic characteristics have not differentiated PCa long-term survivors (LTSs) from unselected patients. Preclinical studies using fecal transplant experiments from LTSs of PCa have revealed delayed tumor growth through unknown mechanisms involving the fecal microbiota. However, features of the fecal microbiome in patients with long-term survival are not well described. METHODS: In this cross-sectional study, comprehensive shotgun metagenomics was performed on stool from PCa patients with long-term survival (n = 16). LTS was defined as >4 years from pancreatectomy and all therapy without recurrence. LTSs were compared to control patients with PCa who completed pancreatectomy and chemotherapy (n = 8). Stool was sequenced using an Illumina NextSeq500. Statistical analyses were performed in R with MicrobiomeSeq and Phyloseq for comparison of LTSs and controls. RESULTS: All patients underwent pancreatectomy and chemotherapy before sample donation. The median time from pancreatectomy of 6 years (4-14 years) for LTSs without evidence of disease compared to a median disease-free survival of 1.8 years from pancreatectomy in the control group. No differences were observed in overall microbial diversity for LTSs and controls using Shannon/Simpson indexes. Significant enrichment of species relative abundance was observed in LTSs for the Ruminococacceae family specifically Faecalibacterium prausnitzii species as well as Akkermansia muciniphila species. CONCLUSIONS: Stool from patients cured from PCa has more relative abundance of Faecalibacterium prausnitzii and Akkermansia muciniphila. Additional studies are needed to explore potential mechanisms by which the fecal microbiota may influence survival in PCa. PLAIN LANGUAGE SUMMARY: Although pancreatic cancer treatments have improved, the number of long-term survivors has remained stagnant with a 5-year overall survival estimate of 9%. Emerging evidence suggests that microbes within the gastrointestinal tract can influence cancer response through activation of the immune system. In this study, we profiled the stool microbiome in long-term survivors of pancreas cancer and controls. Several enriched species previously associated with enhanced tumor immune response were observed including Faecalibacterium prausnitzii and Akkermansia muciniphila. These findings warrant additional study assessing mechanisms by which the fecal microbiota may enhance pancreatic cancer immune response.

A National Assessment of T2 Staging for Intrahepatic Cholangiocarcinoma and the Poor Prognosis Associated with Multifocality.

BACKGROUND: T2 intrahepatic cholangiocarcinoma (ICC) is defined as a solitary tumors with vascular invasion or multifocal tumors including satellite lesions, multiple lesions, and intrahepatic metastases. This study aimed to evaluate the prognosis associated with multifocal tumors. METHODS: The National Cancer Database was queried from 2004 to 2017 for patients with non-metastatic ICC. The patients were grouped based on T2 staging, multifocality, and lymph node involvement. RESULTS: The study enrolled and classified 4887 patients into clinical (c) stage groups as follows: 15.2% with solitary T2N0 (sT2N0) tumors, 21.3% with multifocal T2N0 (mT2N0) tumors, and 63.5% with node-positive (TxN1) disease. Patients with (c)sT2N0 tumors had higher rates of surgical resection than those with (c)mT2N0 or (c)TxN1 disease (33.5% vs 19.7% vs 15.0%; p < 0.01). Median overall survival (OS) was better for the patients with (c)sT2N0 tumors than for those with multifocal and node-positive disease (15.4 vs 10.4 vs 10.4 months; p < 0.01). On multivariate analysis, (c)sT2N0 tumors were associated with better OS than (c)mT2N0 tumors [hazard ratio (HR), 1.31; 95% confidence interval (CI), 1.17-1.46; p < 0.01] or (c)TxN1 disease (HR,1.41; 95% CI 1.28-1.56; p < 0.01). In a subset analysis based on pathologic (p) staging of patients who underwent surgical resection with regional lymphadenectomy, multivariate analysis demonstrated that (p)sT2N0 tumors were associated with better OS than (p)mT2N0 tumors (HR,1.40; 95% CI 1.03-1.92; p = 0.03) or (p)TxN1 disease (HR, 2.05; 95% CI 1.62-2.58; p < 0.01). CONCLUSIONS: Multifocal T2N0 ICC is associated with poor OS and has a disparate prognosis compared with solitary T2N0 disease, even among patients who undergo resection. Future staging criteria should account for the poor outcomes associated with multifocal ICC.

Systemic Therapy for Resected Pancreatic Adenocarcinoma: How Much is Enough?

BACKGROUND: Systemic therapy is an essential part of treatment for pancreatic ductal adenocarcinoma (PDAC). However, not all patients receive every cycle of chemotherapy and even if they do, the impact of reduced dose density (DD) on survival is not known. PATIENTS AND METHODS: A single institutional prospective database was queried for patients with PDAC who underwent curative resection between 2009 and 2018. The primary outcome was DD, defined as the percentage of total planned chemotherapy actually received and associated survival. RESULTS: Of the 126 patients included, 38.9% underwent a neoadjuvant approach, which was associated with a greater median number of completed chemotherapy cycles (5 cycles versus 4 cycles, p < 0.01) and a higher median total DD (93.0% versus 65.0%, p < 0.01), compared with an adjuvant treatment approach. In both groups, adjuvant chemotherapy completion rates were low, with only 55 patients completing all adjuvant cycles. After sequential survival analysis, patients who received a DD ≥ 80% had improved median overall survival (OS) (27.1 months versus 18.6 months, p = 0.01), compared with patients who achieved a DD < 80%. On multivariate Cox proportional-hazards modeling, only the presence of lymphovascular invasion (HR: 1.77, 95% CI: 1.04-2.99, p = 0.04) and DD < 80% (HR: 1.91, 95% CI: 1.23-3.00, p = 0.01) were associated with decreased OS. CONCLUSIONS: In this cohort study, patients who received ≥ 80% DD had significantly better OS. DD should be considered an important prognostic metric in pancreatic cancer, and strategies are needed to improve chemotherapy tolerance to improve patient outcomes.

Is There a Benefit to Adjuvant Chemotherapy in Resected, Early Stage Pancreatic Ductal Adenocarcinoma?

BACKGROUND: The role of systemic therapy for Stage IA pancreatic ductal adenocarcinoma (PDAC) is unclear. The aim of our study was to evaluate the impact of adjuvant chemotherapy (AC) on survival in patients with early stage disease. METHODS: The National Cancer Database was queried from 2006 to 2017 for resected pT1N0M0 (Stage 1A) PDAC. Exclusion criteria included neoadjuvant therapy, radiation, or those who suffered a 90-day mortality. RESULTS: Of the 1526 patients included in the study, 42.2% received AC and 57.8% underwent surgery alone. Patients who received AC were younger, had fewer comorbidities, and were more likely to have private insurance, compared with those treated with surgery alone. Patients who received AC had longer median overall survival (OS) compared with those who underwent surgery alone (105.7 months vs 72.0 months, p < 0.01). Subset analyses based on individual "good" prognostic features (size ≤ 1.0 cm, lymphovascular invasion negative, well/moderately differentiated, margin negative resection) demonstrated improved OS with AC. Following propensity score matching based on key clinicopathologic features, AC remained associated with improved median OS (83.7 months vs 59.8 months, p < 0.01). However, in the cohort with body/tail tumors (101.2 months vs 95.0 months, p = 0.19) and those with all "good" prognostic features (95.9 months vs 90.6 months, p = 0.15), AC was not associated with improved survival. CONCLUSIONS: In resected, Stage IA PDAC, AC is associated with improved overall survival in the vast majority of patients; however, in select cohorts the role of AC is unclear. Further study is needed to tailor treatment to individual patients with PDAC.

Assessing the Reliability and Positive Predictive Value of p16 as a Surrogate for Human Papillomavirus-Mediated E6/7 mRNA Expression in Squamous Cell Carcinoma of the Anal Canal.

BACKGROUND: Human papillomavirus has been implicated in the carcinogenesis of squamous cell carcinoma of the anal canal. p16 expression and the presence of human papillomavirus DNA have been used to define human papillomavirus-positive patients, but neither approach has been validated against the standard of human papillomavirus E6/7 mRNA expression at this disease site. OBJECTIVE: This study aimed to evaluate the acceptability of p16 immunohistochemistry as a surrogate to E6/7 mRNA expression in identifying human papillomavirus-mediated squamous cell carcinoma of the anal canal. DESIGN: This was a retrospective analysis of a previously constructed tissue microarray. SETTINGS: This study was conducted at a tertiary academic center. PATIENTS: Biopsies and resection specimens from patients diagnosed with squamous cell carcinoma of the anal canal at the study institution from 2005 to 2015 were reviewed for sample adequacy. MAIN OUTCOME MEASURES: Concordance between p16 positivity by immunohistochemistry and E6/7 mRNA expression by in situ hybridization was evaluated. Sensitivity, specificity, and positive predictive value were assessed. RESULTS: Among the 25 patients evaluated, p16 and E6/7 mRNA results were concordant in 24 of 25 specimens (96%). Of the 24 concordant samples, there were 23 true positives (p16+ and E6/7+) and 1 true negative (p16- and E6/7-). One specimen was discordant (p16- and E6/7+) between p16 and E6/7 mRNA (4%). This resulted in a sensitivity of 96% and a specificity of 100%. Positive predictive value of p16 immunohistochemistry for E6/7 mRNA expression was 100%. LIMITATIONS: This study was limited by its retrospective nature and small sample size. It only assessed diagnostic parameters rather than prognostic implications. CONCLUSIONS: In this study, the clinically prevalent method of p16 immunohistochemistry showed excellent concordance with the standard of E6/7 mRNA expression and demonstrated its potential to serve as a surrogate for identifying human papillomavirus-induced squamous cell carcinoma of the anal canal. See Video Abstract at http://links.lww.com/DCR/B448. EVALUANDO LA CONFIABILIDAD Y EL VALOR PREDICTIVO POSITIVO DE P, COMO SUSTITUTO DE LA EXPRESIN DE ARNM DE E / , MEDIADA POR EL VIRUS DEL PAPILOMA HUMANO, EN CARCINOMA DE CLULAS ESCAMOSAS DEL CANAL ANAL: ANTECEDENTES:El virus del papiloma humano se ha relacionado en la carcinogénesis del carcinoma de células escamosas del canal anal. La expresión de p16 y la presencia de ADN del virus del papiloma humano, se han utilizado para definir a los pacientes positivos al virus del papiloma humano. Pero ninguno de estos enfoques, han sido validados frente al estándar de oro de la expresión del ARNm del virus del papiloma humano E6 / 7, en este sitio de la enfermedad.OBJETIVO:El estudio tuvo como objetivo, evaluar la aceptabilidad de la inmunohistoquímica del p16, como sustituto de la expresión de ARNm de E6 / 7, en la identificación del carcinoma de células escamosas del canal anal, mediada por virus del papiloma humano.DISEÑO:Fue un análisis retrospectivo de un microarreglo de tejido previamente construido.AJUSTE:El estudio se realizó en un centro académico terciario.PACIENTES:Se revisaron biopsias y muestras de resección de pacientes diagnosticados con carcinoma de células escamosas del canal anal, en la institución del estudio, entre 2005 y 2015 para determinar la idoneidad de la muestra.PRINCIPALES MEDIDAS DE RESULTADO:Se evaluó la concordancia entre la positividad de p16 por inmunohistoquímica y la expresión de ARNm de E6 / 7 por hibridación in situ. Se evaluaron la sensibilidad, especificidad y valor predictivo positivo.RESULTADOS:Entre los 25 pacientes evaluados, los resultados del ARNm de p16 y E6 / 7 fueron concordantes en 24/25 muestras (96%). De las 24 muestras concordantes, hubo 23 positivos verdaderos (p16 + y E6 / 7 +) y un negativo verdadero (p16- y E6 / 7-). Una muestra fue discordante (p16- y E6 / 7 +) entre p16 y ARNm de E6 / 7 (4%). Esto resultó en una sensibilidad del 96% y una especificidad del 100%. El valor predictivo positivo de la inmunohistoquímica de p16 para la expresión de ARNm de E6 / 7 fue del 100%.LIMITACIONES:El estudio estuvo limitado por su naturaleza retrospectiva y por el tamaño pequeño de la muestra. Solamente evaluó los parámetros de diagnóstico, en lugar de las implicaciones pronosticas.CONCLUSIONES:En este estudio, el método clínico prevalente de inmunohistoquímica p16, mostró una excelente concordancia con el estándar de oro de la expresión de ARNm de E6 / 7 y demostró su potencial para servir, como sustituto para identificar el carcinoma de células escamosas del canal anal, inducido por el virus del papiloma humano. Consulte Video Resumen en http://links.lww.com/DCR/B448.

Evaluating the Impact of ESPAC-1 on Shifting the Paradigm of Pancreatic Cancer Treatment.

BACKGROUND: In 2004, the European Study Group for Pancreatic Cancer (ESPAC)-1 long-term data concluded that adjuvant chemotherapy provided a survival benefit for patients with pancreatic ductal adenocarcinoma (PDAC), whereas adjuvant chemoradiation was associated with worse overall survival. In this study, we investigated how long it took for US practice patterns to change following this trial. METHODS: The National Cancer Database was used to identify patients with stage I-III PDAC who underwent R0 or R1 resection followed by adjuvant chemotherapy or chemoradiation between 1998 and 2015. A multivariate analysis was performed to determine predictors of receiving adjuvant chemoradiation in the post-ESPAC-1 era. RESULTS: Between 1998 and 2015, adjuvant chemotherapy use increased from 2.9% to 51.6%, whereas adjuvant chemoradiation decreased from 49.5% to 22.9%. In 2010, adjuvant chemotherapy utilization surpassed that of chemoradiation. For patients diagnosed in the post-ESPAC-1 era, adjuvant chemotherapy (n = 7733) and chemoradiation (n = 6969) groups were compared. Patients who underwent adjuvant chemoradiation were younger, had private insurance, underwent surgery at nonacademic centers, and had more pathologically advanced cancers (all P < 0.01). After 2010, R1 resection was the strongest independent predictor of adjuvant chemoradiation use by multivariate analysis (OR 2.05, CI 1.8-2.3, P < 0.01). CONCLUSIONS: Adjuvant chemotherapy use exceeded that of adjuvant chemoradiation 6 y after the final publication of ESPAC-1 in 2004, highlighting the challenges of disseminating and adopting clinical data. After 2010, R1 disease was the most significant predictor of receiving adjuvant chemoradiation. Prospective studies are underway to definitively address the role of adjuvant chemoradiation in PDAC.

Prognostic implications of advancing nodal stage in anal cancer: evaluating AJCC 8 staging changes through an NCDB analysis.

PURPOSE: In the AJCC8, nodal staging for squamous cell carcinoma of the anus (SCCA) has been changed to a binary format (N0 or N+), and overall stage groups have been redefined. We evaluated the effect of AJCC8 nodal stage by T stage and hypothesized similar survival regardless of the extent of AJCC7-defined nodal involvement. METHODS: The National Cancer Database (NCDB) was used to identify patients' SCCA. Overall survival (OS) for each T stage within the AJCC7 was compared with increasing nodal stage, as well as for the new AJCC8 overall stage groups and subsets. RESULTS: There were 6738 patients analyzed. The 5-year OS by AJCC8 stage was I = 81%, IIA = 78%, IIB = 64%, IIIA = 69%, IIIB = 59%, IIIC = 57% (p < 0.0001). In AJCC8 IIIA (T1-2, N+), there was no difference in 5-year OS between T1N+ or T2N+ patients (70.3% vs 68.6%, p = 0.09). A significant survival difference was demonstrated between AJCC7 N1, N2, and N3 for patients with either T1 (p = 0.0047) or T2 (p = 0.0389) disease. In the AJCC 8 IIIC (T3-4, N+) group, there was no difference in 5-year OS between T3N+ and T4N+ (58% vs 55%, p = 0.81). There was no OS difference between AJCC7 N1-3 for either T3 (p = 0.19) or T4 (0.35) disease. CONCLUSION: For earlier T stages, advancing nodal stage per AJCC7 retains prognostic implications for OS. Survival in AJCC8 stage IIIA is heterogeneous and is largely driven by burden of nodal disease in patients with T1-2 disease.

Intensity-modulated radiotherapy improves survival and reduces treatment time in squamous cell carcinoma of the anus: A National Cancer Data Base study.

BACKGROUND: Chemoradiation with 5-fluorouracil and mitomycin remains the standard of care for squamous cell carcinoma (SCC) of the anal canal. A prolonged treatment time is associated with inferior disease-specific outcomes. Radiation Therapy Oncology Group trial 0529 demonstrated decreased toxicity and fewer treatment breaks with intensity-modulated radiotherapy (IMRT), but this has not been assessed in a randomized trial. Using data from the National Cancer Data Base (NCDB), this study evaluated the impact of IMRT on treatment time and survival in anal SCC. METHODS: The NCDB was used to identify patients with anal cancer from 2004 to 2013. The included patients were those with stage I to III squamous cell cancer of the anal canal who had received definitive chemoradiation by IMRT or 3-dimensional conformal radiation therapy (3DCRT). Statistical analyses were performed with logistic regression, Kaplan-Meier analysis, Cox proportional hazards analysis, and propensity score-matched analysis. RESULTS: Of 6814 patients, 57.4% were treated with 3DCRT, whereas 42.6% received IMRT. Patients receiving IMRT had a reduced risk of a long treatment time in a multivariate analysis (P < .001). The 5-year overall survival (OS) rates with IMRT and 3DCRT were 80.8% and 78.9%, respectively (P = .0036). According to a propensity analysis, patients receiving IMRT had improved OS (P = .039) and a reduced risk of a long treatment time (P < .0001) in a multivariate analysis. CONCLUSIONS: IMRT use was associated with significantly reduced overall treatment time and improved survival in comparison with 3DCRT. It is important to note that NCDB data are not as robust as randomized data. However, these results further support the use of IMRT as part of sphincter-preserving therapy for the anal canal.

Does radiologic response correlate to pathologic response in patients undergoing neoadjuvant therapy for borderline resectable pancreatic malignancy?

BACKGROUND AND OBJECTIVES: In patients with borderline resectable pancreas cancers, clinicians frequently consider radiographic response as the primary driver of whether patients should be offered surgical intervention following neoadjuvant therapy (NT). We sought to determine any correlation between radiographic and pathologic response rates following NT. METHODS: Between 2005 and 2015, 38 patients at a tertiary care referral center underwent NT followed by pancreaticoduodenectomy for borderline resectable pancreas cancer. Radiographic response after the completion of NT and pathologic response after surgery were graded according to RECIST and Evans' criteria, respectively. RESULTS: Preoperatively, 50% of patients underwent chemotherapy alone and 50% underwent chemotherapy and chemoradiation. Radiographically, one patient demonstrated a complete radiologic response, 68.4% (n = 26) of patients had stable disease (SD), 26.3% (n = 10) demonstrated a partial response, and one patient had progressive. Among patients without radiographic response, 77.7% (n = 21) achieved a R0 resection. Of patients with SD on imaging, 26.9% (n = 7) had Evans grade IIB or greater pathologic response. CONCLUSIONS: Our data indicate that approximately one-fourth of patients who did not have a radiologic response had a grade IIB or greater pathologic response. In the absence of metastatic progression, lack of radiographic down-staging following NT should not preclude surgery.

Defining Minimum Treatment Parameters of Ablative Radiation Therapy in Patients With Hepatocellular Carcinoma: An Expert Consensus.

PURPOSE: External beam radiation therapy (EBRT) is a highly effective treatment in select patients with hepatocellular carcinoma (HCC). However, the Barcelona Clinic Liver Cancer system does not recommend the use of EBRT in HCC due to a lack of sufficient evidence and intends to perform an individual patient level meta-analysis of ablative EBRT in this population. However, there are many types of EBRT described in the literature with no formal definition of what constitutes "ablative." Thus, we convened a group of international experts to provide consensus on the parameters that define ablative EBRT in HCC. METHODS AND MATERIALS: Fundamental parameters related to dose, fractionation, radiobiology, target identification, and delivery technique were identified by a steering committee to generate 7 Key Criteria (KC) that would define ablative EBRT for HCC. Using a modified Delphi (mDelphi) method, experts in the use of EBRT in the treatment of HCC were surveyed. Respondents were given 30 days to respond in round 1 of the mDelphi and 14 days to respond in round 2. A threshold of ≥70% was used to define consensus for answers to each KC. RESULTS: Of 40 invitations extended, 35 (88%) returned responses. In the first round, 3 of 7 KC reached consensus. In the second round, 100% returned responses and consensus was reached in 3 of the remaining 4 KC. The distribution of answers for one KC, which queried the a/b ratio of HCC, was such that consensus was not achieved. Based on this analysis, ablative EBRT for HCC was defined as a BED10 ≥80 Gy with daily imaging and multiphasic contrast used for target delineation. Treatment breaks (eg, for adaptive EBRT) are allowed, but the total treatment time should be ≤6 weeks. Equivalent dose when treating with protons should use a conversion factor of 1.1, but there is no single conversion factor for carbon ions. CONCLUSIONS: Using a mDelphi method assessing expert opinion, we provide the first consensus definition of ablative EBRT for HCC. Empirical data are required to define the a/b of HCC.

Application of the patient-reported outcomes continual reassessment method to a phase I study of radiotherapy in endometrial cancer.

This article considers the concept of designing Phase I clinical trials using both clinician- and patient-reported outcomes to adaptively allocate study participants to tolerable doses and determine the maximum tolerated dose (MTD) at the study conclusion. We describe an application of a Bayesian form of the patient-reported outcomes continual reassessment method (PRO-CRMB) in an ongoing Phase I study of adjuvant hypofractionated whole pelvis radiation therapy (WPRT) in endometrial cancer (NCT04458402). The study's primary objective is to determine the MTD per fraction of WPRT, defined by acceptable clinician- and patient-reported DLT rates. We conduct simulation studies of the operating characteristics of the design and compared them to a rule-based approach. We illustrate that the PRO-CRMB makes appropriate dose assignments during the study to give investigators and reviewers an idea of how the method behaves. In simulation studies, the PRO-CRMB demonstrates superior performance to a 5 + 2 stepwise design in terms of recommending target treatment courses and allocating patients to these courses. The design is accompanied by an easy-to-use R shiny web application to simulate operating characteristics at the design stage and sequentially update dose assignments throughout the trial's conduct.

Metagenomic analysis of the fecal microbiome in colorectal cancer patients compared to healthy controls as a function of age.

BACKGROUND AND AIMS: Colorectal cancer (CRC) incidence is increasing in young patients without a clear etiology. Emerging data have implicated the fecal microbiome in CRC carcinogenesis. However, its impact on young onset CRC is poorly defined. METHODS: We performed a meta-analysis of fecal metagenomics sequencing data from n = 692 patients with CRC and n = 602 healthy controls from eleven studies to evaluate features of the fecal metagenome associated with CRC. We hypothesized that known carcinogenic virulence factors (colibactin, fadA) and species abundance may be differentially enriched in young CRC patients relative to older CRC patients and controls. RESULTS: Summary odds ratios (OR) for CRC were increased with the presence of colibactin (OR 1.92 95% CI 1.08-3.38), fadA (OR 4.57 95% CI 1.63-12.85), and F. nucleatum (OR 6.93 95% CI 3.01-15.96) in meta-analysis models adjusted for age, gender, and body mass index. The OR for CRC for the presence of E.coli was 2.02 (0.92-4.45). An increase in the prevalence of Fusobacterium nucleatum (OR = 1.40 [1.18; 1.65]) and Escherichia coli (OR = 1.14 [1.02; 1.28]) per 10-year increase in age was observed in models including samples from both CRC and healthy controls. Species relative abundance was differentially enriched in young CRC patients for five species-Intestinimonas butyriciproducens, Holdemania filiformis, Firimicutues bacterium CAG 83, Bilophilia wadsworthia, and Alistipes putredinis. CONCLUSION: In this study, we observed strong associations with CRC status for colibactin, fadA, and Fusobacterium nucleatum with CRC relative to controls. In addition, we identified several microbial species differentially enriched in young colorectal cancer patients. Studies targeting the young CRC patients are warranted to elucidate underlying preclinical mechanisms.

Neoadjuvant Therapy Regimens for Hilar Cholangiocarcinoma Before Liver Transplant.

OBJECTIVES: Patients with unresectable hilar cholangiocarcinoma (hCCA) may be eligible for curative treatment through liver transplantation (LT). Neoadjuvant protocols often include radiotherapy (RT), however, there is no standard RT approach. The purpose of this study is to characterize practice patterns of RT use before transplantation for hCCA. METHODS: A survey was administered to radiation oncologists practicing at LT centers identified through the U.S. Organ Procurement and Transplant Network and the International Cholangiocarcinoma Research Network. The survey consisted of 13 questions regarding RT details as well as approaches to systemic therapy. For cross-regimen comparison, the cumulative RT tumor dose was standardized using the EQD2 method. RESULTS: Twenty-three centers utilizing neoadjuvant therapy for hCCA were identified. Most respondents (96%) use both chemotherapy and RT as part of their protocol. Elective nodal volumes commonly included the portal vein lymph nodes (91%) and celiac artery lymph nodes (70%). After an initial 45 Gy plan, a wide range of sequential boost regimens was used. The median cumulative dose including boosts to the gross disease was 58 Gy (EQD2) with a wide range of 40 to 110 Gy. Five (22%) include brachytherapy as part of their treatment plan. The majority (96%) used concurrent chemotherapy with fluoropyrimidines. CONCLUSIONS: These results suggest significant variability of neoadjuvant RT use for hCCA before LT. A wide range of doses and fractionation schemes are utilized with cumulative doses ranging from 40 to 110 Gy (EQD2). A further study evaluating the efficacy and toxicity of these various approaches is warranted to better inform best practices.

An Engineered Probiotic Platform for Cancer Epitope-Independent Targeted Radionuclide Therapy of Solid Tumors.

Targeted radionuclide therapy (TRT) is an emerging therapeutic modality for the treatment of various solid cancers. Current approaches rely on the presence of cancer-specific epitopes and receptors against which a radiolabeled ligand is systemically administered to specifically deliver cytotoxic doses of α and ß particles to tumors. In this proof-of-concept study, tumor-colonizing Escherichia coli Nissle 1917 (EcN) is utilized to deliver a bacteria-specific radiopharmaceutical to solid tumors in a cancer-epitope independent manner. In this microbe-based pretargeted approach, the siderophore-mediated metal uptake pathway is leveraged to selectively concentrate copper radioisotopes, 64 Cu and 67 Cu, complexed to yersiniabactin (YbT) in the genetically modified bacteria. 64 Cu-YbT facilitates positron emission tomography (PET) imaging of the intratumoral bacteria, whereas 67 Cu-YbT delivers a cytotoxic dose to the surrounding cancer cells. PET imaging with 64 Cu-YbT reveals persistence and sustained growth of the bioengineered microbes in the tumor microenvironment. Survival studies with 67 Cu-YbT reveals significant attenuation of tumor growth and extends survival of both MC38 and 4T1  tumor-bearing mice harboring the microbes. Tumor response to this pretargeted approach correlates with promising anti-tumor immunity, with noticeable CD8+ T:Treg cell ratio. Their strategy offers a pathway to target and ablate multiple solid tumors independent of their epitope and receptor phenotype.

Feasibility Trial of Intensity Modulated Proton Therapy to Reduce Toxicity in Anal Cancer Patients.

PURPOSE: The purpose of this trial was to assess the patient and physician-reported toxicity in anal cancer patients undergoing definitive chemoradiation with intensity-modulated proton therapy (IMPT). METHODS: Patients with stage II and III anal cancer were treated with IMPT. All patients received 2 cycles of 5-fluorouracil and mitomycin concurrently with radiation. Toxicity was assessed at baseline, weekly during chemoradiation, and in follow-up using physician-graded common terminology criteria for adverse events (CTCAE) v 4.0 and PRO-CTCAE. The primary endpoint was to define point estimates and 95% CI for acute ≥ grade 2/3 gastrointestinal (GI), genitourinary (GU), dermatologic, and hematologic toxicity. The proportion of PRO-CTCAE questions scored ≥3 for each domain was compared with the baselinse. The proportion of ≥ grade 2 and ≥ grade 3 toxicities were compared with historic intensity-modulated radiotherapy patients treated on RTOG 0529. RESULTS: Fourteen patients were enrolled from 2017 to 2020. Rates of physician-reported GI, GU, dermatologic, and hematologic toxicity were not significantly different between patients treated with IMPT compared with patients treated with intensity-modulated radiotherapy. Rates of patient-reported dermatologic and GU toxicity were low at baseline with a peak at week 6 (91% and 58% PRO-CTCAE items ≥ grade 3, respectively) and normalization to baseline 3 months after IMPT. In contrast, the proportion of high-grade PRO-CTCAE GI scores was 40% at baseline, which persisted through 1-year posttreatment. CONCLUSIONS: Clinician-reported toxicity was not improved with IMPT in the context of this underpowered trial. High-grade GI symptoms persisted for 12 months and were similar to baseline. Additional measures are needed to minimize acute and chronic toxicity related to chemoradiation.

Sulforaphane Bioavailability in Healthy Subjects Fed a Single Serving of Fresh Broccoli Microgreens.

Cruciferous vegetable consumption is associated with numerous health benefits attributed to the phytochemical sulforaphane (SFN) that exerts antioxidant and chemopreventive properties, among other bioactive compounds. Broccoli sprouts, rich in SFN precursor glucoraphanin (GRN), have been investigated in numerous clinical trials. Broccoli microgreens are similarly rich in GRN but have remained largely unexplored. The goal of this study was to examine SFN bioavailability and the microbiome profile in subjects fed a single serving of fresh broccoli microgreens. Eleven subjects participated in a broccoli microgreens feeding study. Broccoli microgreens GRN and SFN contents and stability were measured. Urine and stool SFN metabolite profiles and microbiome composition were examined. Broccoli microgreens had similar GRN content to values previously reported for broccoli sprouts, which was stable over time. Urine SFN metabolite profiles in broccoli microgreens-fed subjects were similar to those reported previously in broccoli sprouts-fed subjects, including the detection of SFN-nitriles. We also reported the detection of SFN metabolites in stool samples for the first time. A single serving of broccoli microgreens did not significantly alter microbiome composition. We showed in this study that broccoli microgreens are a significant source of SFN. Our work provides the foundation for future studies to establish the health benefits of broccoli microgreens consumption.

Hematologic Toxicity Comparison of Intensity Modulated Proton Therapy and Intensity Modulated Radiation Therapy in Anal Cancer Patients.

PURPOSE: We hypothesize that hematologic toxicity will be lower in anal cancer patients treated definitively with intensity modulated proton therapy (IMPT) compared with patients treated with intensity modulated radiation therapy (IMRT). METHODS: Patients enrolled on a prospective feasibility trial assessing the use of IMPT for anal cancer were compared with contemporaneous patients treated with IMRT. Blood counts were collected during chemoradiation. Hematologic events were graded according to CTCAE version 5.0. Pelvic bone marrow (PBM) and positron emission tomography-defined active bone marrow (ABM) were defined and contoured for each patient. Toxicity rates, PBM and ABM dose metrics were compared between groups. RESULTS: Forty-one patients treated with definitive chemoradiation for anal cancer between 2015 and 2021 were included in this analysis. Of the evaluable patients, 14 patients were treated with IMPT and 27 were treated with IMRT. All PBM dose metrics were lower in patients receiving IMPT. Patients treated with IMPT versus IMRT also had a significantly lower ABM mean dose (1996 vs. 3073 Gy, P<0.01). However, there was no statistically significant difference in hematologic toxicity between the groups. Seventy percent of patients treated with IMRT had at least 1 grade ≥3 hematologic event compared with 86% in the IMPT group (P=0.48). CONCLUSION: Proton treatment reduced bone marrow doses but was not associated with lower hematologic toxicity when compared with IMRT.

Relationship of dose to vascular target volumes and local failure in pancreatic cancer patients undergoing neoadjuvant chemoradiation.

Objective: The objectives of this study were to evaluate whether dose to the vasculature is associated with local control after surgery in patients with borderline resectable (BLR) and resectable pancreatic cancer (PCA) receiving neoadjuvant radiation therapy (RT) and to identify a dose threshold for clinical use. Methods: Patients with BLR and resectable PCA treated with neoadjuvant RT were retrospectively reviewed. During this period, the institutional paradigm shifted from standard fractionation to hypofractionation/stereotactic body radiation therapy (SBRT). A vasculature clinical target volume (Vasc CTV) was contoured for each patient and defined as a 5-mm margin around the superior mesenteric artery (SMA) from its origin to the pancreatic head, the celiac artery from its origin to the level of the trifurcation and any involved vein. The Vasc CTV D95 was normalized to a 2-Gy equivalent dose to determine the optimal dose associated with optimal local failure-free survival (LFFS). Results: Forty-seven patients were included in the analysis. A Vasc CTV D95 of 32.7 Gy was the optimal cutoff for LFFS. Patients with Vasc CTV D95 Equivalent dose in 2 Gy per fraction (EQD2) >32.7 Gy had significantly longer LFFS compared to patients with Vasc CTV D95 EQD2 ≤32.7 Gy at 12 months (91% vs. 51%, respectively) and 24 months (86% vs. 12%, respectively). The median disease-free survival (DFS) for patients with EQD2 >32.7 Gy was 30.4 months compared to 14.0 months in patients with EQD2 ≤32.7 Gy (p = 0.01). There was no significant difference in overall survival (OS) between the two groups. Conclusions: During neoadjuvant treatment, dose to the Vasc CTV is associated with durability of local control (LC) after resection and should be intentionally included in the treatment volume with an EQD2 goal of 31-33 Gy.

Radiation therapy in borderline resectable pancreatic cancer: A review.

BACKGROUND: Borderline resectable pancreatic cancer constitutes a complex clinical entity, presenting the clinician with a locally aggressive disease that has a proclivity for distant spread. The benefits of radiation therapy, such as improved local control and improved survival, have been questioned. In this review we seek to summarize the existing evidence on radiation therapy in borderline resectable pancreatic cancer and highlight future areas of research. METHODS: A comprehensive review of PubMed for clinical studies reporting outcomes in borderline resectable pancreatic cancer was performed in June 2021, with an emphasis placed on prospective studies. RESULTS: Radiologic "downstaging" in borderline resectable pancreatic cancer is a rare event, although some evidence shows increased clinical response to neoadjuvant chemotherapy over radiation therapy. Margin status seems to be equivalent between regimens that use neoadjuvant chemotherapy alone and regimens that include neoadjuvant radiation therapy. Local control in borderline resectable pancreatic cancer is likely improved with radiation therapy; however, the benefit of improved local control in a disease marked by systemic failure has been questioned. Although some studies have shown improved survival with radiation therapy, differences in the delivery and tolerance of chemotherapy between the neoadjuvant and adjuvant setting confound these results. When the evidence is evaluated as a whole, there is no clear survival benefit of radiation therapy in borderline resectable pancreatic cancer. CONCLUSION: Once considered a staple of therapy, the role of radiation therapy in borderline resectable pancreatic cancer is evolving as systemic therapy regimens continues to improve. Increased clinical understanding of disease phenotype and response are needed to accurately tailor therapy for individual patients and to improve outcomes in this complex patient population.