RAS/RAF Comutation and ERBB2 Copy Number Modulates HER2 Heterogeneity and Responsiveness to HER2-directed Therapy in Colorectal Cancer

PURPOSE

ERBB2-amplified colorectal cancer is a distinct molecular subtype with expanding treatments. Implications of concurrent oncogenic RAS/RAF alterations are not known.

EXPERIMENTAL DESIGN

Dana-Farber and Foundation Medicine Inc. Colorectal cancer cohorts with genomic profiling were used to identify ERBB2-amplified cases [Dana-Farber, n = 47/2,729 (1.7%); FMI, n = 1857/49,839 (3.7%)]. Outcomes of patients receiving HER2-directed therapies are reported (Dana-Farber, n = 9; Flatiron Health-Foundation Medicine clinicogenomic database, FH-FMI CGDB, n = 38). Multisite HER2 IHC and genomic profiling were performed to understand HER2 intratumoral and interlesional heterogeneity. The impact of concurrent RAS comutations on the effectiveness of HER2-directed therapies were studied in isogenic colorectal cancer cell lines and xenografts.

RESULTS

ERBB2 amplifications are enriched in left-sided colorectal cancer. Twenty percent of ERBB2-amplified colorectal cancers have co-occurring oncogenic RAS/RAF alterations. While RAS/RAF WT colorectal cancers typically have clonal ERBB2 amplification, colorectal cancers with co-occurring RAS/RAF alterations have lower level ERRB2 amplification, higher intratumoral heterogeneity, and interlesional ERBB2 discordance. These distinct genomic patterns lead to differential responsiveness and patterns of resistance to HER2-directed therapy. ERBB2-amplified colorectal cancer with RAS/RAF alterations are resistant to trastuzumab-based combinations, such as trastuzumab/tucatinib, but retain sensitivity to trastuzumab deruxtecan in in vitro and murine models. Trastuzumab deruxtecan shows clinical efficacy in cases with high-level ERBB2-amplified RAS/RAF coaltered colorectal cancer.

CONCLUSIONS

Co-occurring RAS/RAF alterations define a unique subtype of ERBB2-amplified colorectal cancer that has increased intratumoral heterogeneity, interlesional discordance, and resistance to trastuzumab-based combinations. Further examination of trastuzumab deruxtecan in this previously understudied cohort of ERBB2-amplified colorectal cancer is warranted.

Mutational signature-based identification of DNA repair deficient gastroesophageal adenocarcinomas for therapeutic targeting

Homologous recombination (HR) and nucleotide excision repair (NER) are the two most frequently disabled DNA repair pathways in cancer. HR-deficient breast, ovarian, pancreatic and prostate cancers respond well to platinum chemotherapy and PARP inhibitors. However, the frequency of HR deficiency in gastric and esophageal adenocarcinoma (GEA) still lacks diagnostic and functional validation. Using whole exome and genome sequencing data, we found that a significant subset of GEA, but very few colorectal adenocarcinomas, show evidence of HR deficiency by mutational signature analysis (HRD score). High HRD gastric cancer cell lines demonstrated functional HR deficiency by RAD51 foci assay and increased sensitivity to platinum chemotherapy and PARP inhibitors. Of clinical relevance, analysis of three different GEA patient cohorts demonstrated that platinum treated HR deficient cancers had better outcomes. A gastric cancer cell line with strong sensitivity to cisplatin showed HR proficiency but exhibited NER deficiency by two photoproduct repair assays. Single-cell RNA-sequencing revealed that, in addition to inducing apoptosis, cisplatin treatment triggered ferroptosis in a NER-deficient gastric cancer, validated by intracellular GSH assay. Overall, our study provides preclinical evidence that a subset of GEAs harbor genomic features of HR and NER deficiency and may therefore benefit from platinum chemotherapy and PARP inhibitors.

Biomarkers of pembrolizumab efficacy in advanced anal squamous cell carcinoma: analysis of a phase II clinical trial and a cohort of long-term responders

BACKGROUND

Recent trials suggest that programmed cell death 1 (PD-1)-directed immunotherapy may be beneficial for some patients with anal squamous cell carcinoma and biomarkers predictive of response are greatly needed.

METHODS

This multicenter phase II clinical trial (NCT02919969) enrolled patients with metastatic or locally advanced incurable anal squamous cell carcinoma (n=32). Patients received pembrolizumab 200 mg every 3 weeks. The primary endpoint of the trial was objective response rate (ORR). Exploratory objectives included analysis of potential predictive biomarkers including assessment of tumor-associated immune cell populations with multichannel immunofluorescence and analysis of circulating tumor tissue modified viral-human papillomavirus DNA (TTMV-HPV DNA) using serially collected blood samples. To characterize the clinical features of long-term responders, we combined data from our prospective trial with a retrospective cohort of patients with anal cancer treated with anti-PD-1 immunotherapy (n=18).

RESULTS

In the phase II study, the ORR to pembrolizumab monotherapy was 9.4% and the median progression-free survival was 2.2 months. Despite the high level of HPV positivity observed with circulating TTMV-HPV DNA testing, the majority of patients had low levels of tumor-associated CD8+PD-1+ T cells on pretreatment biopsy. Patients who benefited from pembrolizumab had decreasing TTMV-HPV DNA scores and a complete responder's TTMV-HPV DNA became undetectable. Long-term pembrolizumab responses were observed in one patient from the trial (5.3 years) and three patients (2.5, 6, and 8 years) from the retrospective cohort. Long-term responders had HPV-positive tumors, lacked liver metastases, and achieved a radiological complete response.

CONCLUSIONS

Pembrolizumab has durable efficacy in a rare subset of anal cancers. However, despite persistence of HPV infection, indicated by circulating HPV DNA, most advanced anal cancers have low numbers of tumor-associated CD8+PD-1+ T cells and are resistant to pembrolizumab.

A Phase I Expansion Cohort Study Evaluating the Safety and Efficacy of the CHK1 Inhibitor LY2880070 with Low-dose Gemcitabine in Patients with Metastatic Pancreatic Adenocarcinoma

PURPOSE

Combining gemcitabine with CHK1 inhibition has shown promise in preclinical models of pancreatic ductal adenocarcinoma (PDAC). Here, we report the findings from a phase I expansion cohort study (NCT02632448) investigating low-dose gemcitabine combined with the CHK1 inhibitor LY2880070 in patients with previously treated advanced PDAC.

PATIENTS AND METHODS

Patients with metastatic PDAC were treated with gemcitabine intravenously at 100 mg/m2 on days 1, 8, and 15, and LY2880070 50 mg orally twice daily on days 2-6, 9-13, and 16-20 of each 21-day cycle. Pretreatment tumor biopsies were obtained from each patient for correlative studies and generation of organoid cultures for drug sensitivity testing and biomarker analyses.

RESULTS

Eleven patients with PDAC were enrolled in the expansion cohort between August 27, 2020 and July 30, 2021. Four patients (36%) experienced drug-related grade 3 adverse events. No objective radiologic responses were observed, and all patients discontinued the trial by 3.2 months. In contrast to the lack of efficacy observed in patients, organoid cultures derived from biopsies procured from two patients demonstrated strong sensitivity to the gemcitabine/LY2880070 combination and showed treatment-induced upregulation of replication stress and DNA damage biomarkers, including pKAP1, pRPA32, and γH2AX, as well as induction of replication fork instability.

CONCLUSIONS

No evidence of clinical activity was observed for combined low-dose gemcitabine and LY2880070 in this treatment-refractory PDAC cohort. However, the gemcitabine/LY2880070 combination showed in vitro efficacy, suggesting that drug sensitivity for this combination in organoid cultures may not predict clinical benefit in patients.

Supportive learning environments, impression management and 'strategic imposterism': A word of caution

Learning environments are critical to individual growth and expression. While high stakes environments can drive self‐doubt and imposterism, the authors warn that overly comfortable environments may encourage ‘strategic imposterism.’

Highly Sensitive Circulating Tumor DNA Assay Aids Clinical Management of Radiographically Occult Isolated Peritoneal Metastases in Patients With GI Cancer

PURPOSE

GI cancers commonly spread to the peritoneal cavity, particularly from primary adenocarcinomas of the stomach and appendix. Peritoneal metastases are difficult to visualize on cross-sectional imaging and cause substantial morbidity and mortality. The purpose of this study was to determine whether serial highly sensitive tumor-informed circulating tumor DNA (ctDNA) measurements could longitudinally track changes in disease burden and inform clinical care.

METHODS

This was a retrospective case series of patients with gastric or appendiceal adenocarcinoma and isolated peritoneal disease that was radiographically occult. Patients underwent quantitative tumor-informed ctDNA testing (Signatera) as part of routine clinical care. No interventions were prespecified based on ctDNA results.

RESULTS

Of 13 patients studied, the median age was 65 (range, 45-75) years, with 7 (54%) women, 5 (38%) patients with gastric, and 8 (62%) patients with appendiceal adenocarcinoma. Eight (62%) patients had detectable ctDNA at baseline measurement, with median value 0.13 MTM/mL (range, 0.06-11.68), and assay was technically unsuccessful in two cases with appendiceal cancer because of limited tumor tissue. Five (100%) patients with gastric cancer and 3 (50%) patients with appendiceal cancer had detectable ctDNA at baseline. Although baseline levels of ctDNA were low, longitudinal assessment tracked with changes in disease burden among patients undergoing chemotherapy for metastatic disease. In two patients undergoing surveillance after definitive surgical management of gastric adenocarcinoma, detection of ctDNA prompted diagnosis of isolated peritoneal disease.

CONCLUSION

Quantitative tumor-informed serial ctDNA testing aids clinical management of patients with isolated peritoneal disease. Low levels of baseline ctDNA suggest a role for highly sensitive ctDNA approaches over panel-based testing. Further exploration of this approach should be considered in patients with isolated peritoneal malignant disease.

Effect of a MUC5AC Antibody (NPC-1C) Administered With Second-Line Gemcitabine and Nab-Paclitaxel on the Survival of Patients With Advanced Pancreatic Ductal Adenocarcinoma: A Randomized Clinical Trial

IMPORTANCE

Treatment options are limited for patients with advanced pancreatic ductal adenocarcinoma (PDAC) beyond first-line 5-fluorouracil, leucovorin, irinotecan, and oxaliplatin (FOLFIRINOX), with such individuals commonly being treated with gemcitabine and nab-paclitaxel.

OBJECTIVE

To determine whether NPC-1C, an antibody directed against MUC5AC, might increase the efficacy of second-line gemcitabine and nab-paclitaxel in patients with advanced PDAC.

DESIGN, SETTING, AND PARTICIPANTS

This multicenter, randomized phase II clinical trial enrolled patients with advanced PDAC between April 2014 and March 2017 whose disease had progressed on first-line FOLFIRINOX. Eligible patients had tumors with at least 20 MUC5AC staining by centralized immunohistochemistry review. Statistical analysis was performed from April to May 2022.

INTERVENTIONS

Patients were randomly assigned to receive gemcitabine (1000 mg/m2) and nab-paclitaxel (125 mg/m2) administered intravenously on days 1, 8, and 15 of every 4-week cycle, with or without intravenous NPC-1C 1.5 mg/kg every 2 weeks.

MAIN OUTCOMES AND MEASURES

The primary end point was overall survival (OS). Secondary end points were progression-free survival (PFS), objective response rate (ORR), and safety. Pretreatment clinical variables were explored with Cox proportional hazards analysis.

RESULTS

A total of 78 patients (median [range] age, 62 [36-78] years; 32 [41%] women; 9 [12%] Black; 66 [85%] White) received second-line treatment with gemcitabine plus nab-paclitaxel (n = 40) or gemcitabine plus nab-paclitaxel and NPC-1C (n = 38). Median OS was 6.6 months (95% CI, 4.7-8.4 months) with gemcitabine plus nab-paclitaxel vs 5.0 months (95% CI, 3.3-6.5 months; P = .22) with gemcitabine plus nab-paclitaxel and NPC-1C. Median PFS was 2.7 months (95% CI, 1.9-4.1 months) with gemcitabine plus nab-paclitaxel vs 3.4 months (95% CI, 1.9-5.3 months; P = .80) with gemcitabine plus nab-paclitaxel and NPC-1C. The ORR was 3.1% (95% CI, 0.4%-19.7%) in the gemcitabine plus nab-paclitaxel and NPC-1C group and 2.9% (95% CI, 0.4%-18.7%) in the gemcitabine plus nab-paclitaxel group. No differences in toxicity were observed between groups, except that grade 3 or greater anemia occurred more frequently in patients treated with gemcitabine plus nab-paclitaxel and NPC-1C than gemcitabine plus nab-paclitaxel (39% [15 of 38] vs 10% [4 of 40]; P = .003). The frequency of chemotherapy dose reductions was similar in both groups (65% vs 74%; P = .47). Lower performance status, hypoalbuminemia, PDAC diagnosis less than or equal to 18 months before trial enrollment, lymphocyte-to-monocyte ratio less than 2.8, and CA19-9 greater than 2000 IU/mL were independently associated with poorer survival.

CONCLUSIONS AND RELEVANCE

In this randomized clinical trial of advanced PDAC, NPC-1C did not enhance the efficacy of gemcitabine/nab-paclitaxel. These data provide a benchmark for future trials investigating second-line treatment of PDAC.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01834235.

Analysis of Circulating Tumor DNA to Predict Risk of Recurrence in Patients With Esophageal and Gastric Cancers

PURPOSE

Circulating tumor DNA (ctDNA) analyses allow for postoperative risk stratification in patients with curatively treated colon and breast cancers. Use of ctDNA in esophagogastric cancers (EGC) is less characterized and could identify high-risk patients who have been treated with curative intent.

METHODS

In this retrospective analysis of real-world data, ctDNA levels were analyzed in the preoperative, postoperative, and surveillance settings in patients with EGC using a personalized multiplex polymerase chain reaction-based next-generation sequencing assay. Plasma samples (n = 943) from 295 patients at > 70 institutions were collected before surgery, postoperatively, and/or serially during routine clinical follow-up from September 19, 2019, to February 21, 2022. ctDNA detection was annotated to clinicopathologic features and recurrence-free survival.

RESULTS

A total of 295 patients with EGC were analyzed, and 212 patients with stages I-III disease were further explored. Pretreatment ctDNA was detected in 96% (23/24) of patients with preoperative time points. Postoperative ctDNA was detected in 23.5% (16/68) of patients with stage I-III EGC within 16 weeks (molecular residual disease window) after surgery without receiving systemic therapy. ctDNA detection at any time point after surgery (hazard ratio [HR], 23.6; 95% CI, 10.2 to 66.0; P < .0001), within the molecular residual disease window (HR, 10.7; 95% CI, 4.3 to 29.3; P < .0001), and during the surveillance period (HR, 17.7; 95% CI, 7.3 to 50.7; P < .0001) was associated with shorter recurrence-free survival. In multivariable analysis, ctDNA status and clinical stage of disease were independently associated with outcomes.

CONCLUSION

Using real-world data, we demonstrate that postoperative tumor-informed ctDNA detection in EGC is feasible and allows for enhanced patient risk stratification and prognostication during curative-intent therapy.

Abstract A019: A multicenter randomized phase II study of gemcitabine and nab-paclitaxel versus gemcitabine and nab-paclitaxel with a MUC5AC antibody (NPC-1C) in advanced pancreatic cancer previously treated with FOLFIRINOX (NCT01834235)

Background: Treatment options for advanced pancreatic ductal adenocarcinoma (PDAC) beyond first-line 5-fluorouracil, irinotecan, and oxaliplatin (FOLFIRINOX) are limited, and patients are commonly treated with gemcitabine and nab-paclitaxel. The aim of this study was to determine whether the addition of a MUC5AC antibody, NPC-1C, could improve the efficacy of second-line gemcitabine and nab-paclitaxel in advanced PDAC. Methods: This study was a multicenter, open label, randomized phase II clinical trial (NCT01834235) for patients with metastatic or locally advanced PDAC who had disease progression on first-line FOLFIRINOX or a FOLFIRINOX-like regimen. Eligible patients had tumors with &gt;20% MUC5AC expression as assessed by centralized immunohistochemistry review. Patients were randomly assigned (1:1 ratio) to receive gemcitabine 1000 mg/m2 and nab-paclitaxel 125 mg/m2 on days 1, 8, and 15 every 4-week cycle with or without IV NPC-1C 1.5 mg/kg every two weeks. The primary endpoint was overall survival (OS). Secondary endpoints were progression free survival (PFS), confirmed overall response rate (ORR) by RECIST v1.1, disease control rate (DCR) (partial response or stable disease ≥ 16 weeks), and safety. Clinical variables associated with survival were explored using Cox proportional hazards stepwise regression analysis. Results: Of the 80 randomized patients, 40 received gemcitabine/nab-paclitaxel (GA) and 38 received gemcitabine/nab-paclitaxel/NPC-1C (GA+N) between April 2014 to March 2017. The median follow-up time was 5.8 months. Enrolled patients had a median age of 62 years (range, 36-78), 32 patients (41%) were female, and 4 patients (5%) had locally advanced disease. The trial was stopped early for futility following a pre-planned interim analysis, and patients were followed. The median OS in the GA arm was 6.6 months (95% confidence interval [CI]: 4.7-8.4) and 5.0 months (95% CI: 3.3-6.5; log-rank p=0.22) in the GA+N arm. The median PFS was 2.7 months (95% CI: 1.9-4.1) for GA and 3.4 months (95% CI: 1.9-5.3; log-rank p=0.80) for GA+N. The ORR (n=66) was 3% (95% CI: 0.4%-19%) for GA and 3% (95% CI: 0.4%-20%) for GA+N. The DCR was 23.5% (95% CI: 12.1%-40.8%) for GA and 28.1% (95% CI: 15.1%-46.2%) for GA+N (Fisher exact, p=0.78). There were minimal differences in toxicity between arms, except grade ≥ 3 anemia was more common in patients treated with GA+N vs. GA (39% vs 10%, Fisher exact, p=0.003). Chemotherapy dose reductions occurred in 69% of all patients at least one time (65% GA vs. 74% GA+N, Fisher exact, p=0.47). Decreased performance status, two or more metastatic sites, lymphocyte-to-monocyte ratio &lt; 2.8, and CA19-9 &gt; 2000 IU/mL were independently correlated with worse outcomes in the full study population. Conclusions: NPC-1C did not enhance the efficacy of gemcitabine and nab-paclitaxel. These data provide a benchmark for survival outcomes, dose modification patterns, and prognostic factors of patients treated with second-line gemcitabine and nab-paclitaxel.

Citation Format: Brandon M. Huffman, Atrayee Basu Mallick, Nora K. Horick, Andrea Wang-Gillam, Peter J. Hosein, Michael Morse, Muhammad Shaalan Beg, Janet E. Murphy, Benjamin L. Schlechter, Hanna Sanoff, Brian M. Wolpin, Philip Arlen, Jill Lacy, James M. Cleary. A multicenter randomized phase II study of gemcitabine and nab-paclitaxel versus gemcitabine and nab-paclitaxel with a MUC5AC antibody (NPC-1C) in advanced pancreatic cancer previously treated with FOLFIRINOX (NCT01834235) [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer; 2022 Sep 13-16; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2022;82(22 Suppl):Abstract nr A019.

Resident impression management within feedback conversations: A qualitative study

INTRODUCTION

Medical education is moving to conceptualise feedback as a bidirectional learning conversation. Within this conversation, learners experience a tension between assessment and feedback. That perceived tension affects learners' outward performances. In this study, we aimed to characterise residents' experiences with this tension and its effect on learner authenticity within feedback conversations.

METHODS

In this constructivist grounded theory study, the authors were informed by Goffman's theory of impression management. During data analysis, Dweck's theory of mindset was adopted. The authors conducted semi-structured interviews with 15 internal medicine residents. Data collection and analysis were conducted iteratively, using constant comparison to identify themes coinciding with impression management and mindset, ultimately developing a theoretical model to help explain residents' responses to tensions within feedback conversations.

RESULTS

Residents constantly felt 'scrutinized', and this affected their engagement in feedback conversations. They staged a performance within those conversations, linked to their underlying mindset: growth or fixed. Growth mindset was characterised by a focus on development as a physician and was associated with asking questions and seeking opportunities for growth. Fixed mindset was characterised by a focus on achieving a favourable evaluation and was associated with a hesitation to ask questions when faced with uncertainty and admit opportunities for growth, because they were concerned about impression management. Context influenced mindset and impression management. Residents adopted a fixed mindset and managed impressions when they perceived the permanence or consequences of evaluations within feedback. Residents adopted a growth mindset when they trusted the supervisor.

DISCUSSION

Residents assess the context of feedback conversations, altering the authenticity of their behaviours. Context, including the perceptions of formal assessment and relationships with supervisors, affected residents' mindset and impression management. Providing space for relationship-building and clarifying the purpose and structure of assessment may be helpful in supporting effective learning conversations in graduate medical education.

Coaching Versus Competency to Facilitate Professional Identity Formation

Professional identity formation, with its focus on the development of professional values, actions, and aspirations, is the ideal goal of medical education. Medicine is a community of practice, and medical education is a socialization process by which novice trainees become full community members. The authors believe coaching provides an ideal means for promoting this socialization process to develop a learner's identity as they engage in the community. Coaching involves an orientation toward growth and development, valuing reflection and nurturing continuous reflection, and embracing failure as an opportunity for learning. However, there are challenges to implementing coaching in medical education. Competency-based medical education has provided clear outcomes (competencies) for medical education and programs of assessment around these competencies. Yet, there is a tension in medical training between professional identity formation (the process of socialization into the profession) and the formal assessment process. The ideal of multiple low-stakes assessments and written evaluations, intended as formative assessments, are perceived by residents as high-stakes evaluations with significant consequences for their future. The authors present a resident story that highlights this tension. They outline Goffman's theory of impression management, postulating that medicine's assessment system encourages residents to stage a performance for evaluators that displays their competence and conceals their perceived weaknesses. This performance hinders coaching and the formation of an appropriate professional identity. Coaching, the authors believe, provides a model that aligns assessment and professional identity formation. Given the challenges to implementing coaching in medical education, the authors propose several questions to contemplate when integrating coaching into medical education to facilitate the goal of professional identity formation.

Clinicopathological features and outcomes of fibrolamellar hepatocellular carcinoma

Background

Clinicopathological features and the outcomes of patients with fibrolamellar hepatocellular carcinoma (FLHCC) are not clearly defined.

Methods

Data were collected by retrospective chart review on 42 patients with FLHCC treated between 1990 and 2017 at Mayo Clinic.

Results

Of 42 patients (median age at diagnosis 22 years), 10 patients (23.8%) had stage I disease and 32 patients (76.2%) had stage II to IVB disease. All 10 patients with stage I disease and 21 of 32 patients with stage II-IVB disease underwent resection at presentation. In stage I patient group, 6 patients experienced recurrence with a median time to recurrence of 30.5 months and a 5-year overall survival (OS) of 86%. Patients with stage II to IVB disease who underwent resection (n=21) upfront had a median OS of 32.5 months and 5-year OS of 44%. In the upfront surgery group, 71% of patients experienced recurrence. The median OS of patients with unresectable disease (n=11) was 10 months. Four out of nine patients treated with sorafenib had stable disease and one patient with programmed cell death ligand-1 (PD-L1) expressing tumor had a near complete response after 2 months of therapy with nivolumab.

Conclusions

In FLHCC, surgical resection was associated with prolonged OS; although most patients had a disease recurrence regardless of disease stage and resection margin status. The response to kinase inhibitor, sorafenib, was variable. In select cases, therapy with a checkpoint inhibitor may provide a viable treatment option.

Validation of lymphocyte to monocyte ratio in resected small bowel adenocarcinoma as a predictor of survival

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Background: Lymphocyte to monocyte ratio (LMR) has been described as a prognostic factor in many solid tumors including colorectal adenocarcinoma. LMR has not been investigated as a prognostic factor in small bowel cancers. In this study, we aimed to evaluate prognostic factors in resected small bowel adenocarcinoma including LMR. Methods: Two hundred forty-one patients who underwent resection for stage I-III small bowel adenocarcinoma were retrospectively identified utilizing the pathology database at a single tertiary referral institution from 1994 to 2015. All patients had complete follow up data and were included in the survival analysis. One hundred sixty-nine patients had preoperative peripheral blood counts available for analysis. Plot of martingale residuals against LMR were used to establish best cutoff points for LMR. A training set for LMR included consecutively identified patients from 2006 to 2015, and a validation cohort including patients identified from 1994 to 2005 was used. Overall survival was performed utilizing Kaplan-Meier method, and Wilcoxon tests were used for statistical comparisons. Cox proportional hazards were performed and all tests were two sided. P value of < 0.05 was considered significant. Results: Median overall survival for the entire group was 54.5 months (95% CI: 37.2-81.2 months) with 5- and 10-year overall survival of 48% and 35%. The training set for LMR included 81 patients, and the validation set included 88 patients. The cutoff of 1.56 was chosen based on most significant p value (p = 0.002). When combined, the overall area under the curve (AUC) for LMR was 0.63, p < 0.01, (specificity 37.3%, sensitivity 90.1%, positive predictive value 33.1%, and negative predictive value 92.2%). There were 126 patients with LMR > 1.56 and 43 patients with LMR < 1.56 in the entire cohort. In multivariate analysis, LMR under 1.56 was a negative prognostic factor, HR = 2.20 (95% CI: 1.27-3.84, p < 0.01). In addition to LMR, age > 60 years and advanced T stage were independently negative predictors of overall survival in all patients. Conclusions: Lymphocyte-to-monocyte ratio < 1.56 is a validated negative prognostic factor in resected small bowel adenocarcinoma.

Novel Prognostic Factors in Resected Small Bowel Adenocarcinoma

BACKGROUND

Small bowel adenocarcinoma (SBA) is a rare malignancy affecting approximately 3000 patients per year in the United States, and there is limited evidence prognosticating patients with resected SBA. We aimed to evaluate prognostic factors and the role of adjuvant therapy in patients with resected SBA.

PATIENTS AND METHODS

Two hundred forty-one patients who had resected stage I-III SBA were retrospectively identified at a single tertiary referral institution. Overall survival (OS) analysis was performed by the Kaplan-Meier method, and Wilcoxon tests were used for statistical comparisons. Cox proportional hazards were performed to identify significant variables by univariate and multivariate analysis.

RESULTS

Median OS for the entire group was 54.5 months (95% confidence interval [CI], 37.2-81.2 months), with 5- and 10-year OS of 48% and 35%. Median follow-up was 113.7 months (95% CI, 97.9-126.6 months). For patients with stage III disease who received adjuvant therapy, the median OS was 33.8 months (95% CI, 27.8-78.8) compared to 24.7 months (95% CI, 11.5-37.8) for patients with no adjuvant therapy (P < .01). Male sex, advanced T stage, advanced N stage, increased positive lymph node ratio, lymphocyte-to-monocyte ratio < 1.56, presence of residual disease, and earlier date of diagnosis predicted worse survival on univariate analysis. Age > 60 years, lymphocyte-to-monocyte ratio < 1.56, and advanced T stage were identified as independent negative predictors of OS for all patients by multivariate analysis.

CONCLUSION

Advanced age, advanced T stage, and lymphocyte-to-monocyte ratio < 1.56 independently predicted survival in resected SBA. Adjuvant therapy is associated with improved survival in patients with resected stage III SBA.

Local excision for patients with stage I anal canal squamous cell carcinoma can be curative

Background

Definitive concurrent chemoradiation is the current standard of care for all stage I anal canal squamous cell carcinoma. Local excision as primary treatment for selected stage I lesions has been reported in the literature but is not currently recommended by major guidelines. We herein compared the oncologic outcomes of patients with stage I anal canal squamous cell carcinoma treated with local excision alone versus chemoradiation to determine if there are any significant differences in outcomes including disease free survival, overall survival (OS) and local failure rate.

Methods

A retrospective review of all patients treated for stage I anal canal squamous cell carcinoma between 1990 and 2016 was conducted. Data collected included baseline demographics, staging studies, pathology, treatment received, relapse pattern and survival.

Results

A total of 57 patients were treated for stage I anal canal squamous cell carcinoma between 1990 and 2016; 13 were treated with local excision alone and 44 were treated with chemoradiation therapy. Baseline characteristics in both cohorts of patients were comparable. Median follow-up duration of the local excision and the chemoradiation cohorts were 106 and 70 months, respectively. Of the 13 patients in local excision cohort, two patients had disease recurrence, at 21 and 97 months from the diagnosis. Both patients were long term survivors with salvage treatment. In chemoradiation cohort, 1 out of 44 patients had a local recurrence at 1 year who underwent curative resection. Five-year progression free survival (PFS) of subjects in local excision cohort and chemoradiation cohort were 91% and 83%, respectively (P=0.57).

Conclusions

Local excision as primary treatment may be safe and effective for a selected group of stage I anal canal squamous cell carcinoma patients.

Clinicopathological features and outcomes of fibrolamellar hepatocellular carcinoma

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Background: Clinicopathological features and the outcomes of patients with fibrolamellar hepatocellular carcinoma (FLHCC) are not clearly defined. Methods: Data were collected by retrospective chart review on 42 patients with FLHCC treated between 1990 and 2017 at the Mayo Clinic. Clinicopathological characteristics, response to treatment, recurrence pattern and survival were analyzed. Results: Of 42 patients (17 males and 25 females; median age at diagnosis 22 years, range 15 to 39), 10 patients (23%) had stage I disease and 32 patients (77%) had stage II to IVB disease. All 10 patients with stage I disease and 21 of 32 patients with stage II-IVB disease underwent resection at presentation. In stage I patient group, 6 patients experienced recurrence with a median time to recurrence of 30.5 months, resulting in a 5 year overall survival (OS) of 86%. Patients with stage II to IVB disease who underwent resection (n=21) at presentation had a median OS of 32.5 months and 5 year OS of 44%. In the upfront surgery group, 71% of the patients experienced recurrent disease. The median OS of patients with unresectable disease (n=11) was 10 months. Systemic therapy was given to 17 patients which included sorafenib, FOLFOX (5-fluorouracil/leucovorin and oxaliplatin), gemcitabine plus oxaliplatin, single agent adriamycin or gemcitabine, capecitabine plus interferon alfa, gemcitabine plus cisplatin, cisplatin plus adriamycin and nivolumab . Sorafenib was given to 9 patients and 4 patients achieved stable disease (SD) with duration ranging from 5 months to 5 years. One programmed cell death receptor positive-1 patient had a durable complete response after 2 months of therapy with nivolumab. Conclusions: In FLHCC, surgical resection was associated with prolonged OS. However, recurrences were common after the surgery. Limited benefit was derived from the systemic treatment. In rare cases, therapy with a checkpoint inhibitor may provide a viable treatment option.

Lymphocyte-to-monocyte ratio and neutrophil-to-lymphocyte ratio independently predict survival in resected small bowel adenocarcinoma

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Background: Small bowel adenocarcinoma is a rare malignancy affecting approximately 2,000 patients per year. There is a paucity of evidence prognosticating patients with small bowel adenocarcinoma. We aimed to evaluate multiple factors in patients with resected small bowel adenocarcinoma to determine any association with survival outcomes. Methods: Ninety three patients who underwent resection for stage I-III small bowel adenocarcinoma were retrospectively identified utilizing the pathology database at a single tertiary referral institution. All patients had complete follow up data and were included in the survival analysis. JMP software was used for statistical analysis. Overall survival was performed utilizing Kaplan-Meier method, and log-rank tests were used for statistical comparisons. Cox proportional hazards were performed to control for age, gender, location of tumor, tumor size, tumor stage, and adjuvant therapy. Sensitivity analysis was performed to establish best cutoff points for continuous variables. All tests were two sided and a P value of < 0.05 was considered significant. Results: The median age at diagnosis was 65 years (range 32-90). 61% were male. Median tumor size was 4.5 cm. There were 20, 36, and 37 patients with stage I, stage II, and stage III disease, respectively. Median overall survival (OS) was 151 months, 104 months, and 44 months for stages I, II, and III disease. In a multivariate analysis, independent predictor factors included presurgical lymphocyte to monocyte ratio (LMR) > 4.0, with a Hazard Ratio (HR) 0.13 (95% CI 0.007-0.69, p = 0.01), presurgical neutrophil to lymphocyte ratio (NLR) < 8.0, HR 0.39 (95% CI 0.17-0.96, p = 0.04), and tumor size < 7.5 cm, HR 0.22 (95% CI 0.07-0.85, p = 0.03). Stage, age, T stage, and N stage influenced overall survival in univariate analysis, but were not statistically significant on multivariate analysis. Conclusions: LMR and NLR independently predict survival in patients with resected small bowel adenocarcinoma.

Prognostic factors in duodenal adenocarcinoma

e15797

Background: Duodenal adenocarcinoma is a rare tumor representing approximately 0.3% of all gastrointestinal tract cancers. Prognostic factors in relation to survival outcomes for these patients are sporadically reported in the medical literature. We aimed to evaluate outcomes of patients with duodenal adenocarcinoma who underwent pancreaticojejunostomy treated at Mayo Clinic Rochester from January 1, 2006 to December 31, 2016. Methods: Clinicopathological data of 52 duodenal cancer patients were collected. JMP software was used for statistical analysis. Kaplan-Meier method and log-rank tests were used for survival analysis, and multivariate cox proportional hazards model was used to evaluate the prognostic effect of pertinent clinical variables. All tests were two sided and a P value of < 0.05 was considered significant. Results: The median age at diagnosis was 65.9 years (range 39-81). The median overall survival was 51 months (95% CI 31.3-105.4) and the median progression free survival was 30.4 months with median follow up of 73.4 months. There were 3, 9, 21, and 19 patients with stage I, II, III, and IV disease, respectively. Depth of tumor invasion (p = 0.0156) and lymph node metastasis (p = 0.0441) were associated with overall survival on multivariate analysis. Advanced clinical staging influenced overall survival in univariate analysis, but lost prognostic significance in multivariate analysis. Age, gender, surgical technique, presence of metastases, tumor size, number of lymph nodes removed, location of duodenal segment involvement, and adjuvant treatment had no significant impact on overall survival. Laparoscopic approach did not influence survival but was associated with less hospital days (p = 0.0437). Conclusions: Depth of tumor invasion and lymph node status were associated with improved overall survival in patients with duodenal adenocarcinoma. Laparoscopic procedure decreased the hospital stay without affecting outcomes.

Occult pulmonary mucosa-associated lymphoid tissue lymphoma presenting as catastrophic antiphospholipid antibody syndrome

Catastrophic antiphospholipid antibody syndrome (CAPS) is characterized by fulminant thrombosis of the arterial and venous beds of multiple organ systems over a relatively short period of time and with a high mortality rate. Mucosa-associated lymphoid tissue (MALT) lymphoma of the lung has never been reported as a causative or precipitating factor for CAPS in the CAPS registry database. The present study describes a rare case of pulmonary MALT lymphoma of the lung that presented as CAPS. A 19-year-old Hispanic female presented with shortness of breath and abdominal pain. Computed tomography (CT) scans of the chest and abdomen revealed multiple portal vein thromboses and bilateral pulmonary nodules. Within one week of presentation, the patient developed a straight sinus thrombosis and upper extremity deep vein thrombosis, which led to shortness of breath. A biopsy of the lung nodule revealed MALT lymphoma. The present case illustrates a rarely reported pulmonary MALT lymphoma presenting as CAPS in a young female. The patient was successfully treated with 90 mg/m² bendamustine on days one and two and rituximab 375 mg/m² on day one of each 28-day cycle. Complete remission of the lung nodules was observed following three cycles of treatment, as visualized by positron emission tomography (PET)/CT scan. Fondaparinux was identified as a feasible anticoagulation drug of choice for this case. At seven months post-treatment, the patient continues to be stable with no further evidence of thrombosis and is currently undergoing rituximab maintenance therapy every six months for two years. A repeat lupus anticoagulant antibody assay turned and remained negative during the clinical follow-up period. A prompt diagnosis and early aggressive treatment is potentially curative and may dramatically decrease the mortality risk. Future studies should explore the role of rituximab in the management of CAPS-associated B-cell lymphoid malignancies.