Attitudes of physicians and patients toward immediate and intraoperative chemotherapy treatment in colon cancer.

INTRODUCTION: We have shown in a Phase I trial that immediate adjuvant chemotherapy (IAC) during surgical resection and immediately postoperative is safe and feasible in patients with colon cancer (CC). IAC avoids delays in adjuvant treatment and has the potential to improve survival and quality of life. We aim to determine patients and providers attitudes toward this novel multidisciplinary treatment approach. METHODS: Two web-based surveys were administered to newly diagnosed CC patients, survivors, surgeons and oncologists. Surveys assessed treatment preferences and perceived barriers to IAC. Chi-square tests were conducted to compare differences between patients' and providers' responses. RESULTS: Responses were collected from 35 patients and 40 providers. Patients were more willing to: (1) proceed with IAC to finish treatment earlier thus possibly improving quality of life (p = 0.001); (2) proceed with IAC despite potential side effects (p < 0.001); and (3) proceed with a dose of intraoperative chemotherapy even if on final pathology, may not have been needed (p = 0.002). Patients were more likely to indicate no barriers to collaborative care (p = 0.001) while providers were more likely to cite that it is time consuming, thus a barrier to participation (p = 0.001), has scheduling challenges (p = 0.001), and physicians are not available to participate (p = 0.003). CONCLUSIONS: We observed a discordance between what providers and patients value in perioperative and adjuvant CC treatment. Patients are willing to accept IAC despite potential side effects and without survival benefit, highlighting the importance of understanding patient preference.

A Phase 1 Study of Cabozantinib and Trifluridine/Tipiracil in Metastatic Colorectal Adenocarcinoma.

INTRODUCTION: This study determined the safety and recommended phase 2 dose (RP2D) of the multikinase inhibitor cabozantinib in combination with trifluridine/tipiracil (FTD/TPI) in refractory metastatic colorectal carcinoma (mCRC). PATIENTS AND METHODS: Single institution investigator-initiated phase 1 study using 3+3 design. Eligible mCRC patients had received prior standard regimens. Cabozantinib was given orally (p.o.) at 20 mg (dose level [DL] 0) or 40 mg (DL 1) daily on days 1-28, and FTD/TPI p.o. at 35 mg/m2 on days 1-5 and 8-12 every 28 days. Prophylactic growth-factor support was allowed. RESULTS: Fifteen patients were enrolled. Median age 56 years (31-80), male (12/15), ECOG 0/1 = 9/6. Three patients were treated at DL 0 and another nine were treated at DL 1, none exhibiting a DLT. Most common any grade (G) treatment related adverse events (TRAE) were diarrhea (50%), nausea (42%), neutropenia (42%), fatigue (33%), and rash (25%). G3-4 TRAE were neutropenia (25%) and thrombocytopenia, hypokalemia, and weight loss (each 8%). No serious TRAE or G5 were reported. The RP2D was determined to be DL 1. Median PFS was 3.8 months (95% CI 1.9-6.8) and disease control rate was 86.7%. CONCLUSION: The combination of cabozantinib and FTD/TPI is feasible and tolerable at standard doses with the use of growth factors and showed encouraging clinical activity in refractory mCRC. CLINICALTRIALS: GOV: NCT04868773.

Disparities in Receipt of National Comprehensive Cancer Network Guideline-Adherent Care and Outcomes among Women with Triple-Negative Breast Cancer by Race/Ethnicity, Socioeconomic Status, and Insurance Type.

BACKGROUND: The National Comprehensive Cancer Network guidelines were designed to improve patient outcomes. Here, we examine factors that may contribute to outcomes and guideline adherence in patients with triple-negative breast cancer. METHODS: This was a retrospective cohort study of women with triple-negative breast cancer using the California Cancer Registry. Adherent treatment was defined as the receipt of a combination of surgery, lymph node assessment, adjuvant radiation, and/or chemotherapy. A multivariable logistic regression was used to determine the effects of independent variables on adherence to the NCCN guidelines. Disease-specific survival was calculated using Cox regression analysis. RESULTS: A total of 16,858 women were analyzed. Black and Hispanic patients were less likely to receive guideline-adherent care (OR 0.82, 95%CI 0.73-0.92 and OR 0.87, 95%CI 0.79-0.95, respectively) compared to White patients. Hazard ratios adjusted for adherent care showed that Black patients had increased disease-specific mortality (HR 1.28, 95%CI 1.16-1.42, p < 0.0001) compared to White patients. CONCLUSIONS: A significant majority of breast cancer patients in California continue to receive non-guideline-adherent care. Non-Hispanic Black patients and patients from lower SES quintile groups were less likely to receive guideline-adherent care. Patients with non-adherent care had worse disease-specific survival compared to recipients of NCCN guideline-adherent care.

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

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

Phase IIa Clinical Biomarker Trial of Dietary Arginine Restriction and Aspirin in Colorectal Cancer Patients.

After potentially curative treatment, colorectal cancer (CRC) patients remain at high risk for recurrence, second primary CRC, and high-risk adenomas. In combination with existing data, our previous findings provide a rationale for reducing tissue polyamines as tertiary prevention in non-metastatic CRC patients. The goal of this study was to demonstrate rectal tissue polyamine reduction in optimally treated stage I-III CRC patients after intervention with daily oral aspirin + dietary arginine restriction. A single-institution phase IIa clinical trial was conducted. Patients were treated with aspirin 325 mg/day and an individualized dietary regimen designed to reduce arginine intake by ≥30% over a 12-week study period. Dietary intake, endoscopy with rectal biopsies, and phlebotomy were performed pre- and post-intervention. The primary endpoint was to demonstrate ≥50% decrease in rectal tissue putrescine levels from baseline as a measure of polyamine reduction in the target tissue. Twenty eligible patients completed the study. After study intervention, mean dietary arginine intake decreased from 3.7 g/day ± 1.3 SD to 2.6 g/day ± 1.2 SD (29.7% decrease, p < 0.02 by Sign test). Mean plasma arginine levels decreased from 46.0 ng/mL ± 31.5 SD at baseline to 35 ng/mL ± 21.7 SD (p < 0.001). Rectal tissue putrescine levels were 0.90 nMol/mg-protein pre-intervention and 0.99 nMol/mg-protein post-intervention (p < 0.64, NS). No significant differences were observed for the other tissue polyamines investigated: spermidine (p < 0.13), spermine (p < 0.21), spermidine:spermine ratio (p < 0.71). Among CRC survivors, treatment with daily oral aspirin and an individualized dietary arginine restriction intervention resulted in lower calculated dietary arginine intake and plasma arginine levels but did not affect rectal tissue polyamine levels.

Clinical implications of conflicting variant interpretations in the cancer genetics clinic.

PURPOSE: The aim of this study was to describe the clinical impact of commercial laboratories issuing conflicting classifications of genetic variants. METHODS: Results from 2000 patients undergoing a multigene hereditary cancer panel by a single laboratory were analyzed. Clinically significant discrepancies between the laboratory-provided test reports and other major commercial laboratories were identified, including differences between pathogenic/likely pathogenic and variant of uncertain significance (VUS) classifications, via review of ClinVar archives. For patients carrying a VUS, clinical documentation was assessed for evidence of provider awareness of the conflict. RESULTS: Fifty of 975 (5.1%) patients with non-negative results carried a variant with a clinically significant conflict, 19 with a pathogenic/likely pathogenic variant reported in APC or MUTYH, and 31 with a VUS reported in CDKN2A, CHEK2, MLH1, MSH2, MUTYH, RAD51C, or TP53. Only 10 of 28 (36%) patients with a VUS with a clinically significant conflict had a documented discussion by a provider about the conflict. Discrepant counseling strategies were used for different patients with the same variant. Among patients with a CDKN2A variant or a monoallelic MUTYH variant, providers were significantly more likely to make recommendations based on the laboratory-reported classification. CONCLUSION: Our findings highlight the frequency of variant interpretation discrepancies and importance of clinician awareness. Guidance is needed on managing patients with discrepant variants to support accurate risk assessment.

Population-Based Analysis of National Comprehensive Cancer Network (NCCN) Guideline Adherence for Patients with Anal Squamous Cell Carcinoma in California.

PURPOSE: We analyzed adherence to the National Comprehensive Cancer Network treatment guidelines for anal squamous cell carcinoma in California and the associated impacts on survival. METHODS: This was a retrospective study of patients in the California Cancer Registry aged 18 to 79 years with recent diagnoses of anal squamous cell carcinoma. Predefined criteria were used to determine adherence. Adjusted odds ratios and 95% confidence intervals were estimated for those receiving adherent care. Disease-specific survival (DSS) and overall survival (OS) were examined with a Cox proportional hazards model. RESULTS: 4740 patients were analyzed. Female sex was positively associated with adherent care. Medicaid status and low socioeconomic status were negatively associated with adherent care. Non-adherent care was associated with worse OS (Adjusted HR 1.87, 95% CI = 1.66, 2.12, p < 0.0001). DSS was worse in patients receiving non-adherent care (Adjusted HR 1.96, 95% CI = 1.56, 2.46, p < 0.0001). Female sex was associated with improved DSS and OS. Black race, Medicare/Medicaid, and low socioeconomic status were associated with worse OS. CONCLUSIONS: Male patients, those with Medicaid insurance, or those with low socioeconomic status are less likely to receive adherent care. Adherent care was associated with improved DSS and OS in anal carcinoma patients.

A human vascularized microtumor model of patient-derived colorectal cancer recapitulates clinical disease.

Accurately modeling tumor biology and testing novel therapies on patient-derived cells is critically important to developing therapeutic regimens personalized to a patient's specific disease. The vascularized microtumor (VMT), or "tumor-on-a-chip," is a physiologic preclinical cancer model that incorporates key features of the native human tumor microenvironment within a transparent microfluidic platform, allowing rapid drug screening in vitro. Herein we optimize methods for generating patient-derived VMT (pVMT) using fresh colorectal cancer (CRC) biopsies and surgical resections to test drug sensitivities at the individual patient level. In response to standard chemotherapy and TGF-ßR1 inhibition, we observe heterogeneous responses between pVMT derived from 6 patient biopsies, with the pVMT recapitulating tumor growth, histological features, metabolic heterogeneity, and drug responses of actual CRC tumors. Our results suggest that a translational infrastructure providing rapid information from patient-derived tumor cells in the pVMT, as established in this study, will support efforts to improve patient outcomes.

Assessment of Attitudes Toward Initiation of Immediate Adjuvant Chemotherapy for Colon Cancer.

INTRODUCTION: Early initiation of chemotherapy after surgery for colon cancer has survival benefits. Immediate adjuvant chemotherapy (IAC) involves giving chemotherapy during surgical resection and immediately postoperatively. This novel approach has been shown to be safe, eliminating delays in adjuvant treatment that could increase the risk of micro-metastatic spread. The aim of this study was to assess the willingness of the general public to accept IAC. MATERIALS AND METHODS: Between March and April 2021, 800 telephone interviews were conducted with a sample of adult New York State residents. The Survey Research Institute of Cornell University conducted all surveys. Kruskal-Wallis, chi-squared, and Fisher's tests were conducted using R 4.0.2. RESULTS: Three scenarios were presented: (1) receiving IAC resulting in improved survival and quality of life, (2) finishing chemotherapy earlier without survival impact, and (3) finishing chemotherapy earlier but with possible side effects. Respondents with higher education were more likely to accept (1) & (2), males were more likely to accept (2) & (3), higher income respondents were more likely to accept (1) & (3), and those with more work hours were more likely to accept (2). Lastly, 16% responded they would be very or extremely likely, and 52% respondents would be somewhat likely or likely to accept intraoperative chemotherapy, even if it may not be necessary. CONCLUSIONS: Respondents were likely to accept IAC if offered. Given the known risk of delayed adjuvant chemotherapy (AC) in colon cancer, further research is warranted to determine the survival and quality of life (QOL) benefits of IAC.

Differential Effects of Race, Socioeconomic Status, and Insurance on Disease-Specific Survival in Rectal Cancer.

BACKGROUND: National Comprehensive Cancer Network guideline adherence improves cancer outcomes. In rectal cancer, guideline adherence is distributed differently by race/ethnicity, socioeconomic status, and insurance. OBJECTIVE: This study aimed to determine the independent effects of race/ethnicity, socioeconomic status, and insurance status on rectal cancer survival after accounting for differences in guideline adherence. DESIGN: This was a retrospective study. SETTINGS: The study was conducted using the California Cancer Registry. PATIENTS: This study included patients aged 18 to 79 years diagnosed with rectal adenocarcinoma between January 1, 2004, and December 31, 2017, with follow-up through November 30, 2018. Investigators determined whether patients received guideline-adherent care. MAIN OUTCOME MEASURES: ORs and 95% CIs were used for logistic regression to analyze patients receiving guideline-adherent care. Disease-specific survival analysis was calculated using Cox regression models. RESULTS: A total of 30,118 patients were examined. Factors associated with higher odds of guideline adherence included Asian and Hispanic race/ethnicity, managed care insurance, and high socioeconomic status. Asians (HR, 0.80; 95% CI, 0.72-0.88; p < 0.001) and Hispanics (HR, 0.91; 95% CI, 0.83-0.99; p = 0.0279) had better disease-specific survival in the nonadherent group. Race/ethnicity were not factors associated with disease-specific survival in the guideline adherent group. Medicaid disease-specific survival was worse in both the nonadherent group (HR, 1.56; 95% CI, 1.40-1.73; p < 0.0001) and the guideline-adherent group (HR, 1.18; 95% CI, 1.08-1.30; p = 0.0005). Disease-specific survival of the lowest socioeconomic status was worse in both the nonadherent group (HR, 1.42; 95% CI, 1.27-1.59) and the guideline-adherent group (HR, 1.20; 95% CI, 1.08-1.34). LIMITATIONS: Limitations included unmeasured confounders and the retrospective nature of the review. CONCLUSIONS: Race, socioeconomic status, and insurance are associated with guideline adherence in rectal cancer. Race/ethnicity was not associated with differences in disease-specific survival in the guideline-adherent group. Medicaid and lowest socioeconomic status had worse disease-specific survival in both the guideline nonadherent group and the guideline-adherent group. See Video Abstract at http://links.lww.com/DCR/B954 . EFECTOS DIFERENCIALES DE LA RAZA, EL NIVEL SOCIOECONMICO COBERTURA SOBRE LA SUPERVIVENCIA ESPECFICA DE LA ENFERMEDAD EN EL CNCER DE RECTO: ANTECEDENTES: El cumplimiento de las guías de la National Comprehensive Cancer Network mejora los resultados del cáncer. En el cáncer de recto, el cumplimiento de las guías se distribuye de manera diferente según la raza/origen étnico, nivel socioeconómico y el cobertura médica.OBJETIVO: Determinar los efectos independientes de la raza/origen étnico, el nivel socioeconómico y el estado de cobertura médica en la supervivencia del cáncer de recto después de tener en cuenta las diferencias en el cumplimiento de las guías.DISEÑO: Este fue un estudio retrospectivo.ENTORNO CLINICO: El estudio se realizó utilizando el Registro de Cáncer de California.PACIENTES: Pacientes de 18 a 79 años diagnosticados con adenocarcinoma rectal entre el 1 de enero de 2004 y el 31 de diciembre de 2017 con seguimiento hasta el 30 de noviembre de 2018. Los investigadores determinaron si los pacientes recibieron atención siguiendo las guías.PRINCIPALES MEDIDAS DE RESULTADO: Se utilizaron razones de probabilidad e intervalos de confianza del 95 % para la regresión logística para analizar a los pacientes que recibían atención con adherencia a las guías. El análisis de supervivencia específico de la enfermedad se calculó utilizando modelos de regresión de Cox.RESULTADOS: Se analizaron un total de 30.118 pacientes. Los factores asociados con mayores probabilidades de cumplimiento de las guías incluyeron raza/etnicidad asiática e hispana, seguro de atención administrada y nivel socioeconómico alto. Los asiáticos e hispanos tuvieron una mejor supervivencia específica de la enfermedad en el grupo no adherente HR 0,80 (95 % CI 0,72 - 0,88, p < 0,001) y HR 0,91 (95 % CI 0,83 - 0,99, p = 0,0279). La raza o el origen étnico no fueron factores asociados con la supervivencia específica de la enfermedad en el grupo que cumplió con las guías. La supervivencia específica de la enfermedad de Medicaid fue peor tanto en el grupo no adherente HR 1,56 (IC del 95 % 1,40 - 1,73, p < 0,0001) como en el grupo adherente a las guías HR 1,18 (IC del 95 % 1,08 - 1,30, p = 0,0005). La supervivencia específica de la enfermedad del nivel socioeconómico más bajo fue peor tanto en el grupo no adherente HR 1,42 (IC del 95 %: 1,27 a 1,59) como en el grupo adherente a las guías HR 1,20 (IC del 95 %: 1,08 a 1,34).LIMITACIONES: Las limitaciones incluyeron factores de confusión no medidos y la naturaleza retrospectiva de la revisión.CONCLUSIONES: La raza, el nivel socioeconómico y cobertura médica están asociados con la adherencia a las guías en el cáncer de recto. La raza/etnicidad no se asoció con diferencias en la supervivencia específica de la enfermedad en el grupo que cumplió con las guías. Medicaid y el nivel socioeconómico más bajo tuvieron peor supervivencia específica de la enfermedad tanto en el grupo que no cumplió con las guías como en los grupos que cumplieron. Consulte Video Resumen en http://links.lww.com/DCR/B954 . (Traducción- Dr. Francisco M. Abarca-Rendon).

BRCA-Mutated Pancreatic Cancer: From Discovery to Novel Treatment Paradigms.

The discovery of BRCA1 and BRCA2 in the 1990s revolutionized the way we research and treat breast, ovarian, and pancreatic cancers. In the case of pancreatic cancers, germline mutations occur in about 10-20% of patients, with mutations in BRCA1 and BRCA2 being the most common. BRCA genes are critical in DNA repair pathways, particularly in homologous recombination, which has a serious impact on genomic stability and can contribute to cancerous cell proliferation. However, BRCA1 also plays a fundamental role in cell cycle checkpoint control, ubiquitination, control of gene expression, and chromatin remodeling, while BRCA2 also plays a role in transcription and immune system response. Therefore, mutations in these genes lead to multiple defects in cells that may be utilized when treating cancer. BRCA mutations seem to confer a prognostic benefit with an improved overall survival due to differing underlying biology. These mutations also appear to be a predictive marker, with patients showing increased sensitivity to certain treatments, such as platinum chemotherapy and PARP inhibitors. Olaparib is currently indicated for maintenance therapy in metastatic PDAC after induction with platinum-based chemotherapy. Resistance has been found to these therapies, and with a 10.8% five-year OS, novel therapies are desperately needed.

Adoptive T-Cell Therapy in Advanced Colorectal Cancer: A Systematic Review.

Colorectal cancer (CRC) is the second leading cause of cancer-related deaths in the US. For the vast majority of patients with advanced CRC (ie, for those in whom metastatic tumors are unresectable), treatment is palliative and typically involves chemotherapy, biologic therapy, and/or immune checkpoint inhibition. In recent years, the use of adoptive T-cell therapy (ACT), leveraging the body's own immune system to recognize and target cancer, has become increasingly popular. Unfortunately, while ACT has been successful in the treatment of hematological malignancies, it is less efficacious in advanced CRC due in part to a lack of productive immune infiltrate. This systematic review was conducted to summarize the current data for the efficacy and safety of ACT in advanced CRC. We report that ACT is well tolerated in patients with advanced CRC. Favorable survival estimates among patients with advanced CRC receiving ACT demonstrate promise for this novel treatment paradigm. However, additional stage I/II clinical trials are needed to establish the efficacy and safety of ACT in patients with CRC.

Immediate Adjuvant Chemotherapy in Non-Metastatic Colon Cancer: Phase I Trial Evaluating a Novel Treatment Protocol.

BACKGROUND: The optimal timing of adjuvant chemotherapy (AC) in non-metastatic colon cancer is poorly defined. Delays in AC result in decreased survival. Effective cytotoxic treatments should be considered during the perioperative phase of care. The immediate adjuvant chemotherapy (IAC) concept intends to capitalize on the therapeutic benefits that can be achieved in the perioperative period. We aim to demonstrate that IAC is safe and tolerable. PATIENT AND METHODS: Microsatellite stable invasive adenocarcinomas were treated with intravenous Leucovorin 20 mg/m2 and single dose of 5-Flurouracil 400mg/m2 at the time of surgery. High-risk stage II and stage III received the first dose of standard AC at 14 days after surgery. Serial measurements of blood-based biomarkers were measured. Quality of life (QOL) was measured using EORTC QLQ-C30. RESULTS: Of the 20 patients recruited, 40% had final pathology of stage III, 40% stage II and 20% stage I. All patients received intra-operative chemotherapy with no associated morbidity. Median length of stay was 2 days (range of 2-4). There was no intraoperative morbidity with 5% (N = 1) grade 3 complication. AC was administered to 65% of patients. The median time to AC was 14 days (range 14-36). Overall quality of life and health scores were similar before surgery and at 30-day postoperatively (P < .05). CONCLUSIONS: A protocol based on IAC starting at the time of surgical resection was found to be safe and feasible with no adverse effects on surgical morbidity or quality of life. Further prospective studies are needed to explore the oncologic benefit of this novel systemic treatment approach.

Surgical Management of Gynecologic Cancers.

This article addresses the role of surgery in the management of gynecologic cancers with liver metastases. The authors review the short-term and long-term outcomes of aggressive resection through retrospective and randomized studies. Although the data supporting aggressive resection of liver metastasis are largely retrospective and case based, the randomized control data to address neoadjuvant versus chemotherapy have been widely criticized. Residual disease remains an important predictor for survival in ovarian cancer. If a patient cannot achieve near optimal cytoreduction, radical cytoreductive procedures, such as hepatic resection, should be considered for palliation only.

Increased incidence of early onset colorectal adenocarcinoma is accompanied by an increased incidence of rectal neuroendocrine tumors.

Recent studies have reported an increasing incidence of early onset colorectal cancer (CRC). Few studies compared the changing incidence of CRC by the major histological type, adenocarcinoma and neuroendocrine tumors (NETs). Using data from the Surveillance, Epidemiology, and End Results Program (SEER), we identified CRC from 1992 to 2015 with site and histological codes. Standardized incidence rates of CRC by anatomical locations (proximal, distal and rectal colon) and histological types (adenocarcinoma, NETs and others) were calculated over calendar years. Annual percent changes (APC) and joint-point regression were further computed. A significant increase of cancers in the distal colon and rectum was observed in young populations (20-44 and 45-54 years) but not in the proximal colon. Further analyses found that the highest rise of rectal NETs was in the 45-54 years which contributed 53.47% to the total increase of rectal cancer. The APCs for NETs in the rectum were 2.9 (95% CI: -0.1, 6.0) and 6.1 (95% CI: 3.8-8.4) for 20-44 years or 45-54 years respectively. The increase of NETs in the rectum was still significant in the older than 55 years (APC=3.7, 95% CI: 2.8-4.7), although the total CRC in this group was decreasing. Incidence of NETs in the distal colon is not apparently changing. The increase of CRC incidence among young populations (age < 55) is mainly due to the increased incidence in the rectum and distal colon. Moreover, the increase of early onset cancer in the rectum could be ascribed to increased incidence of adenocarcinoma and NETs.

ctDNA applications and integration in colorectal cancer: an NCI Colon and Rectal-Anal Task Forces whitepaper.

An increasing number of studies are describing potential uses of circulating tumour DNA (ctDNA) in the care of patients with colorectal cancer. Owing to this rapidly developing area of research, the Colon and Rectal-Anal Task Forces of the United States National Cancer Institute convened a panel of multidisciplinary experts to summarize current data on the utility of ctDNA in the management of colorectal cancer and to provide guidance in promoting the efficient development and integration of this technology into clinical care. The panel focused on four key areas in which ctDNA has the potential to change clinical practice, including the detection of minimal residual disease, the management of patients with rectal cancer, monitoring responses to therapy, and tracking clonal dynamics in response to targeted therapies and other systemic treatments. The panel also provides general guidelines with relevance for ctDNA-related research efforts, irrespective of indication.

A Phase IIa Trial of Metformin for Colorectal Cancer Risk Reduction among Individuals with History of Colorectal Adenomas and Elevated Body Mass Index.

Obesity is associated with risk of colorectal adenoma (CRA) and colorectal cancer. The signaling pathway activated by metformin (LKB1/AMPK/mTOR) is implicated in tumor suppression in ApcMin/+ mice via metformin-induced reduction in polyp burden, increased ratio of pAMPK/AMPK, decreased pmTOR/mTOR ratio, and decreased pS6Ser235/S6Ser235 ratio in polyps. We hypothesized that metformin would affect colorectal tissue S6Ser235 among obese patients with recent history of CRA. A phase IIa clinical biomarker trial was conducted via the U.S. National Cancer Institute-Chemoprevention Consortium. Nondiabetic, obese subjects (BMI ≥30) ages 35 to 80 with recent history of CRA were included. Subjects received 12 weeks of oral metformin 1,000 mg twice every day. Rectal mucosa biopsies were obtained at baseline and end-of-treatment (EOT) endoscopy. Tissue S6Ser235 and Ki-67 immunostaining were analyzed in a blinded fashion using Histo score (Hscore) analysis. Among 32 eligible subjects, the mean baseline BMI was 34.9. Comparing EOT to baseline tissue S6Ser235 by IHC, no significant differences were observed. Mean (SD) Hscore at baseline was 1.1 (0.57) and 1.1 (0.51) at EOT; median Hscore change was 0.034 (P = 0.77). Similarly, Ki-67 levels were unaffected by the intervention. The adverse events were consistent with metformin's known side-effect profile. Among obese patients with CRA, 12 weeks of oral metformin does not reduce rectal mucosa pS6 or Ki-67 levels. Further research is needed to determine what effects metformin has on the target tissue of origin as metformin continues to be pursued as a colorectal cancer chemopreventive agent.

Improved survival with adjuvant chemotherapy in locally advanced rectal cancer patients treated with preoperative chemoradiation regardless of pathologic response.

OBJECTIVE: The aim of this study is to examine the effect of postoperative chemotherapy on survival in patients with stage II or III rectal adenocarcinoma who undergo neoadjuvant chemoradiation (CRT) and surgical resection. METHODS: A retrospective review of the National Cancer Database (NCDB) from 2006 to 2013 was performed. Cases were analyzed based on pathologic complete response (pCR) status and use of adjuvant therapy. The Kaplan-Meier method was used to estimate overall survival probabilities. RESULTS: 23,045 cases were identified, of which 5832 (25.31%) achieved pCR. In the pCR group, 1513 (25.9%) received adjuvant chemotherapy, and in the non-pCR group, 5966 (34.7%) received adjuvant therapy. In the pCR group, five-year survival probability was 87% (95% CI 84%-89%) with adjuvant therapy and 81% (95% CI 79%-82%) without adjuvant therapy. In the non-pCR group, five-year survival probability was 78% (95% CI 76%-79%) with adjuvant therapy and 70% (95% CI 69%-71%) without adjuvant therapy. In the non-pCR and node-negative subgroup (ypN-), five-year survival probability was 86% (95% CI 84%-88%) with adjuvant therapy and 76% (95% CI 74%-77%) without adjuvant therapy. In the non-pCR and node-positive subgroup (ypN+), five-year survival probability was 67% (95% CI 65%-70%) with adjuvant therapy and 60% (95% CI 58%-63%) without adjuvant therapy. CONCLUSIONS: Adjuvant chemotherapy in stage II or III rectal adenocarcinoma is associated with increased five-year survival probability regardless of pCR status. We observed similar survival outcomes among non-pCR ypN- treated with adjuvant chemotherapy compared with patients achieving pCR treated with adjuvant chemotherapy.

An ultrasensitive test for profiling circulating tumor DNA using integrated comprehensive droplet digital detection.

Current cancer detection systems lack the required sensitivity to reliably detect minimal residual disease (MRD) and recurrence at the earliest stages when treatment would be most effective. To address this issue, we present a novel liquid biopsy approach that utilizes an integrated comprehensive droplet digital detection (IC3D) digital PCR system which combines microfluidic droplet partitioning, fluorescent multiplex PCR chemistry, and our rapid 3D, large-volume droplet counting technology. The IC3D ddPCR assay can detect cancer-specific, ultra-rare genomic targets due to large sample input and high degree of partitioning. We first demonstrate our droplet digital PCR assay can robustly detect common cancer mutants including KRAS G12D spiked in wild-type genomic background or isolated from patient samples with 100% specificity. We then demonstrate that the IC3D ddPCR system can detect oncogenic KRAS G12D mutant alleles against a background of wild-type genomes at a sensitivity of 0.00125-0.005% with a false positive rate of 0% which is 50 to 1000× more sensitive than existing commercial liquid biopsy ddPCR and qPCR platforms, respectively. In addition, our technology can uniquely enable detection of circulating tumor cells using their genetic markers without a pre-enrichment step, and analysis of total tumor DNA isolated from blood samples, which will increase clinical sensitivity and specificity, and minimize inter-assay variability. Therefore, our technology holds the potential to provide clinicians with a powerful decision-making tool to monitor and treat MRD with unprecedented sensitivity for earlier stage intervention.

The impact of gender, race, socioeconomic status, and treatment on outcomes in esophageal cancer: A population-based analysis.

BACKGROUND: African Americans and Hispanics are reported to have higher mortality from esophageal cancer (EC) than Caucasians. In this study, we analyzed the independent effects of race, gender, treatment, and socioeconomic status (SES) on overall survival (OS). METHODS: Data for all EC cases between 2004 and 2010 with follow-up through 2012 were obtained from the California Cancer Registry. We conducted descriptive analyses of clinical variables and survival analyses by Kaplan-Meier and Cox proportional hazards methods. RESULTS: African Americans and Hispanics were more likely to be in the lower SES strata and less likely to receive surgery than Caucasians in this cohort. The proportion of patients receiving chemotherapy and radiotherapy was similar across different racial/ethnic groups. After adjustment for stage, grade, histology, treatments, and SES in multivariate analyses, the mortality risk in African Americans (hazard ratio [HR] 0.96, 95% confidence interval [CI] 0.85-1.07) and Hispanics (HR 0.96, 95% CI 0.89-1.07) did not differ from Caucasians (HR = 1.00, referent), with histology, SES, and surgery largely accounting for unadjusted OS differences. We also observed that African American men had higher adjusted risk of death relative to Caucasian men (HR 1.24, 95% CI 1.07-1.42), but this effect was not observed for African American women compared to Caucasian women (HR 1.12, 95% CI 0.94-1.35). CONCLUSIONS: Race is not an independent risk factor for OS in our population-based analysis of EC cases. Rather, observed differences in OS by race/ethnicity result from differences in cancer histology, SES, surgery, and gender. Our findings support further health disparities research for this disease.