Genomic signatures of past and present chromosomal instability in Barrett's esophagus and early esophageal adenocarcinoma.

The progression of precancerous lesions to malignancy is often accompanied by increasing complexity of chromosomal alterations but how these alterations arise is poorly understood. Here we perform haplotype-specific analysis of chromosomal copy-number evolution in the progression of Barrett's esophagus (BE) to esophageal adenocarcinoma (EAC) on multiregional whole-genome sequencing data of BE with dysplasia and microscopic EAC foci. We identify distinct patterns of copy-number evolution indicating multigenerational chromosomal instability that is initiated by cell division errors but propagated only after p53 loss. While abnormal mitosis, including whole-genome duplication, underlies chromosomal copy-number changes, segmental alterations display signatures of successive breakage-fusion-bridge cycles and chromothripsis of unstable dicentric chromosomes. Our analysis elucidates how multigenerational chromosomal instability generates copy-number variation in BE cells, precipitates complex alterations including DNA amplifications, and promotes their independent clonal expansion and transformation. In particular, we suggest sloping copy-number variation as a signature of ongoing chromosomal instability that precedes copy-number complexity. These findings suggest copy-number heterogeneity in advanced cancers originates from chromosomal instability in precancerous cells and such instability may be identified from the presence of sloping copy-number variation in bulk sequencing data.

Prolonged Air Leak After Pulmonary Resection Increases Risk of Noncardiac Complications, Readmission, and Delayed Hospital Discharge: A Propensity Score-adjusted Analysis.

OBJECTIVE: The aim of the study was to determine whether prolonged air leak (PAL) is associated with postoperative morbidity and mortality following pulmonary resection after adjusting for differences in baseline characteristics using propensity score analysis. SUMMARY BACKGROUND DATA: Patients with PAL after lung resection have worse outcomes than those without PAL. However, adverse postoperative outcomes may also be secondary to baseline risk factors, such as poor lung function. METHODS: Patients who underwent pulmonary resection for lung cancer/nodules (1/2009-6/2014) were stratified by the presence of PAL [n = 183 with/1950 without; defined as >5 d postoperative air leak; n = 189 (8.3%)]; probability estimates for propensity for PAL from 31 pretreatment/intraoperative variables were generated. Inverse probability-of-treatment weights were applied and outcomes assessed with logistic regression. RESULTS: Standardized bias between groups was significantly reduced after propensity weighting (mean = 0.18 before vs 0.08 after, P < 0.01). After propensity weighting, PAL was associated with increased odds of empyema (OR = 8.5; P < 0.001), requirement for additional chest tubes for pneumothorax (OR = 7.5; P < 0.001), blood transfusion (OR = 2; P = 0.03), pulmonary complications (OR = 4; P < 0.001), unexpected return to operating room (OR = 4; P < 0.001), and 30-day readmission (OR = 2; P = 0.009). Among other complications, odds of cardiac complications (P = 0.493), unexpected ICU admission (P = 0.156), and 30-day mortality (P = 0.270) did not differ. Length of hospital stay was prolonged (5.04 d relative effect, 95% confidence interval, 3.77-6.30; P < 0.001). CONCLUSIONS: Pulmonary complications, readmission, and delayed hospital discharge are directly attributable to having a PAL, whereas cardiac complications, unexpected admission to the ICU, and 30-day mortality are not after propensity score adjustment.

Anastomotic complications after esophagectomy: Influence of omentoplasty in propensity-weighted cohorts.

OBJECTIVE: A recent meta-analysis of 3 randomized controlled trials reported reduced incidence and severity of postesophagectomy anastomotic dehiscence with anastomotic omentoplasty. Unfortunately, these trials excluded neoadjuvant patients who received chemoradiation. We aimed to determine whether anastomotic omentoplasty was associated with differential postesophagectomy anastomotic complications after neoadjuvant chemoradiotherapy. METHODS: Data for patients who underwent minimally invasive esophagectomy following neoadjuvant chemoradiotherapy were abstracted (n = 245; 2001-2016; omentoplasty = 147 [60%]). Propensity for omentoplasty was estimated on 21 pretreatment variables, using augmented inverse probability of treatment weights, and used to determine the adjusted proportion of adverse anastomotic outcomes, major morbidity, and 30-day/in-hospital mortality. RESULTS: Overall, anastomotic leak rate was 15%; leak-associated mortality was 13% (n = 5 out of 37). Leak rates (omentoplasty n = 24 [16%] vs no omentoplasty n = 13 [13%]; P = .512) and incidence of any major complications (48% vs 48%; P = .958) were similar. Leaks requiring surgical intervention occurred in 12 patients (5% vs 5%; P = .904). Propensity weighting achieved excellent balance across all 21 pretreatment variables (before weighting, standardized differences ranged from -0.23 to 0.35; postweighting standardized differences ranged from -0.09 to 0.07). In propensity-weighted data, omentoplasty was not associated with differential adjusted risk of anastomotic leak (13.2% vs 14.3%; P = .83), major morbidity (27.9% vs 32.6%; P = .44), or mortality (6.7% vs 4.8%; P = .61). CONCLUSIONS: Within the limits of our sample size and statistical approach, our study failed to find evidence that anastomotic omentoplasty during esophagectomy after neoadjuvant chemoradiation reduced anastomotic leak rate or need for leak-related reoperation.

The Association of Nicotine Replacement Therapy With Outcomes Among Smokers Hospitalized for a Major Surgical Procedure.

BACKGROUND: There are concerns that starting nicotine replacement therapy (NRT) in the immediate perioperative period may negatively impact wound healing. We investigated the association of NRT with postoperative outcomes among smokers hospitalized for a surgical procedure. METHODS: This was a retrospective study in 552 hospitals of active smokers hospitalized between January 1, 2015 and December 31, 2016 for a major surgical procedure (Medicare Severity Diagnosis-Related Group expected length of stay, ≥ 2 days). We analyzed the association of receipt of NRT within 2 days of admission with a composite outcome of inpatient complications and with other outcomes. We developed a propensity score for receipt of NRT and examined differences in outcomes in a propensity-matched cohort. RESULTS: Of 147,506 active smokers, 25,651 (17.4%) were prescribed NRT within 2 days of admission. Patients treated with NRT were younger; less likely to be black or Hispanic; more likely to have Medicaid; and more likely to have a diagnosis of alcohol or other substance use disorder, or COPD, compared with those who were not treated. In the propensity-matched analysis, there was no association between receipt of NRT and in-hospital complications (OR, 0.99; 95% CI, 0.93-1.05), mortality (OR, 0.84; 95% CI, 0.68-1.04), all-cause 30-day readmissions (OR, 1.02; 95% CI, 0.97-1.07), or 30-day readmission for wound complications (OR, 0.96; 95% CI, 0.86-1.07). CONCLUSIONS: This is the first large observational study of surgical patients to demonstrate that perioperative NRT is not associated with adverse outcomes after surgery. These results strengthen the evidence that NRT should be prescribed routinely in the perioperative period.

Loss of ARID1A expression is associated with DNA mismatch repair protein deficiency and favorable prognosis in advanced stage surgically resected esophageal adenocarcinoma.

Esophageal adenocarcinoma often presents at an advanced stage and has a dismal prognosis. Current prognostic markers have limited utility. ARID1A is implicated as a tumor suppressor gene in esophageal adenocarcinoma. Loss of ARID1A expression correlates with DNA mismatch repair (MMR) protein deficiency in other tumors. We hypothesized that ARID1A loss is associated with prognosis and DNA MMR protein deficiency in esophageal adenocarcinoma. Tissue microarrays representing 316 surgically resected esophageal adenocarcinomas without neoadjuvant treatment were evaluated for ARID1A and MMR proteins by immunohistochemistry. Loss of ARID1A expression (ARID1A-loss) was detected in 41 of 316 (13%) adenocarcinomas. MMR deficiency was identified in 5% (17/316) but was detected more frequently in ARID1A-loss adenocarcinomas (13/41, 32%) than in ARID1A-retained adenocarcinomas (4/275, 1%; P < .001). Morphologically, ARID1A-loss adenocarcinomas frequently demonstrated peritumoral lymphoid aggregates (90%) and tumor infiltrating lymphocytes (51%). In patients with locally advanced or metastatic disease (stages III or IV, N = 169), patients with ARID1A-loss adenocarcinomas (N = 22) had longer overall survival than patients with ARID1A-retained adenocarcinomas (median [month]: 26 vs. 16, P = .010). In these patients, ARID1A-loss correlated with a 56% reduction in mortality independent of other prognostic factors (P = .007). In summary, loss of ARID1A expression is associated with DNA MMR protein deficiency in esophageal adenocarcinoma. Furthermore, ARID1A loss is independently associated with a more favorable prognosis for patients with locally advanced or metastatic esophageal adenocarcinomas.

Percutaneous computed tomography-guided biopsy performed by thoracic surgeons in 955 patients: A paradigm shift in image-guided thoracic procedures.

OBJECTIVES: Computed tomography-guided fine needle aspiration (CT-FNA) biopsy is a well-established diagnostic technique in the evaluation of lung nodules that is performed by radiologists in most centers. In this series, we analyzed the diagnostic and perioperative outcomes following CT-FNA performed by a dedicated group of thoracic surgeons. METHODS: We conducted a retrospective analysis of 955 patients undergoing CT-FNA by the thoracic surgery service. Primary outcome variables included diagnostic yield and accuracy, number of needle passes, complication rates, and adequacy of specimen for molecular testing. RESULTS: A satisfactory diagnostic specimen was obtained in 94.1% of cases. The average number of needle passes was 3.2 ± 1.5 (range, 1-10 passes). Diagnostic yield was significantly improved by increasing the number of passes from 1 to 2 to 3 passes (P = .0003). CT-FNA diagnostic accuracy was 88.8%. Diagnostic accuracy did not significantly improve with ≥4 passes (P = .20). Molecular testing was successful in 43.1%, and did not improve with ≥4 passes (P = .5). Molecular testing success did improve with the addition of core needle biopsy (P = .005). The pneumothorax rate for CT-FNA alone was 26.4%, and increased with ≥4 passes (P = .009). The median length of stay for CT-FNA alone was 0 days (range, 0-74 days), with same-day discharge in 67.5% of patients. CONCLUSIONS: Thoracic surgeons can perform CT-FNA with excellent diagnostic yield and accuracy. Diagnostic yield, accuracy, and success in molecular testing do not improve with ≥4 CT-FNA passes. Pneumothorax rates do increase with ≥4 passes. The addition of core needle biopsy enhances success with molecular testing.

Extreme chromosome 17 copy number instability is a prognostic factor in patients with gastroesophageal adenocarcinoma: A retrospective cohort study.

Gastric and esophageal cancers frequently show genomic instability and aneuploidy. Chromosomal copy number instability (CIN) is a form of genomic instability that exerts pleiotropic effects on cellular biology and is a source of genetic heterogeneity in a population of cells. CIN results in cell-to-cell variation in chromosome copy number which can be detected and quantified by fluorescence in situ hybridization (FISH). CIN is a biomarker associated with differential response to a number of chemotherapy compounds. We quantified chromosome 17 copy number instability (CIN-17) in 348 gastroesophageal adenocarcinomas by centromeric FISH in cases that were tested for HER2 amplification. We evaluated the association between CIN-17 and clinical outcome after surgical and nonsurgical treatment. CIN-17 was detected in 45.4% (158/348) and extreme CIN-17 in 28.4% (99/348). Extreme CIN-17 had no association with outcome in surgically treated patients. However, in patients treated with conventional radiation and/or chemotherapy, extreme CIN-17 was associated with 55% reduction in overall mortality (hazard ratio, 0.448; 95% confidence interval, 0.263-0.763) after adjusting for age and clinical stage at diagnosis. Extreme CIN-17 is detected in over a quarter of gastroesophageal adenocarcinomas and is a favorable prognostic marker in patients treated nonoperatively.

Genomic Heterogeneity as a Barrier to Precision Medicine in Gastroesophageal Adenocarcinoma.

Gastroesophageal adenocarcinoma (GEA) is a lethal disease where targeted therapies, even when guided by genomic biomarkers, have had limited efficacy. A potential reason for the failure of such therapies is that genomic profiling results could commonly differ between the primary and metastatic tumors. To evaluate genomic heterogeneity, we sequenced paired primary GEA and synchronous metastatic lesions across multiple cohorts, finding extensive differences in genomic alterations, including discrepancies in potentially clinically relevant alterations. Multiregion sequencing showed significant discrepancy within the primary tumor (PT) and between the PT and disseminated disease, with oncogene amplification profiles commonly discordant. In addition, a pilot analysis of cell-free DNA (cfDNA) sequencing demonstrated the feasibility of detecting genomic amplifications not detected in PT sampling. Lastly, we profiled paired primary tumors, metastatic tumors, and cfDNA from patients enrolled in the personalized antibodies for GEA (PANGEA) trial of targeted therapies in GEA and found that genomic biomarkers were recurrently discrepant between the PT and untreated metastases. Divergent primary and metastatic tissue profiling led to treatment reassignment in 32% (9/28) of patients. In discordant primary and metastatic lesions, we found 87.5% concordance for targetable alterations in metastatic tissue and cfDNA, suggesting the potential for cfDNA profiling to enhance selection of therapy.Significance: We demonstrate frequent baseline heterogeneity in targetable genomic alterations in GEA, indicating that current tissue sampling practices for biomarker testing do not effectively guide precision medicine in this disease and that routine profiling of metastatic lesions and/or cfDNA should be systematically evaluated. Cancer Discov; 8(1); 37-48. ©2017 AACR.See related commentary by Sundar and Tan, p. 14See related article by Janjigian et al., p. 49This article is highlighted in the In This Issue feature, p. 1.

Mesh cruroplasty in laparoscopic repair of paraesophageal hernias is not associated with better long-term outcomes compared to primary repair.

BACKGROUND: Equipoise still exists regarding routine mesh cruroplasty during laparoscopic paraesophageal hernia (PEH). We aimed to determine whether selective mesh cruroplasty is associated with differences in recurrence and patient-reported outcomes. METHODS: We compared symptom outcomes (n = 688) and radiographic recurrences (n = 101; at least 10% [or 2 cm] of stomach above hiatus) for 795 non-emergent PEH repair with fundoplication (n = 106 with mesh). RESULTS: Heartburn, regurgitation, epigastric pain, and anti-reflux medication use decreased significantly in both groups while postoperative dysphagia (mesh; p = 0.14), and bloating (non-mesh; p = 0.32), were unchanged. Radiographic recurrence rates were similar (15 mesh [22%] versus 86 non-mesh [17%]; p = 0.32; median 27 [IQR 14, 53] months), but was associated with surgical dissatisfaction (13% vs 4%; p = 0.007). CONCLUSIONS: Selective mesh cruroplasty was not associated with differences in symptom outcomes or radiographic recurrence rates during laparoscopic PEH repair. Radiographic recurrence was associated with dissatisfaction, emphasizing the need for continued focus on reducing recurrences.

Targeting Immune Checkpoints in Esophageal Cancer: A High Mutational Load Tumor.

Checkpoint inhibitors (eg, programmed cell death protein 1 [PD-1], programmed cell death ligand 1 [PD-L1], cytotoxic T-lymphocyte associated protein 4 [CTLA-4] antibodies) are changing how we understand cancer and provide a means to develop modern immunotherapies. An emergent notion relates success with checkpoint inhibitors with high mutational load tumors. There are few studies that examine checkpoint protein expression and relate these to clinical outcomes after the conventional treatment of patients with esophageal cancer, which has a high mutational load. The objective of this review is to summarize the literature that examines checkpoint expression and clinical outcomes, as well as propose an accelerated approach to introducing these therapies into the clinic to treat patients with esophageal cancer.

A clinical prediction model for prolonged air leak after pulmonary resection.

OBJECTIVE: Prolonged air leak increases costs and worsens outcomes after pulmonary resection. We aimed to develop a clinical prediction tool for prolonged air leak using pretreatment and intraoperative variables. METHODS: Patients who underwent pulmonary resection for lung cancer/nodules (from January 2009 to June 2014) were stratified by prolonged parenchymal air leak (>5 days). Using backward stepwise logistic regression with bootstrap resampling for internal validation, candidate variables were identified and a nomogram risk calculator was developed. RESULTS: A total of 2317 patients underwent pulmonary resection for lung cancer/nodules. Prolonged air leak (8.6%, n = 200) was associated with significantly longer hospital stay (median 10 vs 4 days; P < .001). Final model variables associated with increased risk included low percent forced expiratory volume in 1 second, smoking history, bilobectomy, higher annual surgeon caseload, previous chest surgery, Zubrod score >2, and interaction terms for right-sided thoracotomy and wedge resection by thoracotomy. Wedge resection, higher body mass index, and unmeasured percent forced expiratory volume in 1 second were protective. Derived nomogram discriminatory accuracy was 76% (95% confidence interval [CI], 0.72-0.79) and facilitated patient stratification into low-, intermediate- and high-risk groups with monotonic increase in observed prolonged air leaks (2.0%, 8.9%, and 19.2%, respectively; P < .001). Patients at intermediate and high risk were 4.80 times (95% CI, 2.86-8.07) and 11.86 times (95% CI, 7.21-19.52) more likely to have prolonged air leak compared with patients at low risk. CONCLUSIONS: Using readily available candidate variables, our nomogram predicts increasing risk of prolonged air leak with good discriminatory ability. Risk stratification can support surgical decision making, and help initiate proactive, patient-specific surgical management.

Non-Elective Paraesophageal Hernia Repair Portends Worse Outcomes in Comparable Patients: a Propensity-Adjusted Analysis.

INTRODUCTION: Patients undergoing non-elective paraesophageal hernia repair (PEHR) have worse perioperative outcomes. Because they are usually older and sicker, however, these patients may be more prone to adverse events, independent of surgical urgency. Our study aimed to determine whether non-elective PEHR is associated with differential postoperative outcome compared to elective repair, using propensity-score weighting. METHODS: We abstracted data for patients undergoing PEHR (n = 924; non-elective n = 171 (19 %); 1997-2010). Using boosted regression, we generated a propensity-weighted dataset. Odds of 30-day/in-hospital mortality and major complications after non-elective surgery were determined. RESULTS: Patients undergoing non-elective repair were significantly older, had more adverse prognostic factors, and significantly more major complications (38 versus 18 %; p < 0.001) and death (8 versus 1 %; p < 0.001). After propensity weighting, median absolute percentage bias across 28 propensity-score variables improved from 19 % (significant imbalance) to 5.6 % (well-balanced). After adjusting propensity-weighted data for age and comorbidity score, odds of major complications were still nearly two times greater (OR 1.67, CI 1.07-2.61) and mortality nearly three times greater (OR 2.74, CI 0.93-8.1) than for elective repair. CONCLUSIONS: Even after balancing significant differences in baseline characteristics, non-elective PEHR was associated with worse outcomes than elective repair. Symptomatic patients should be referred for elective repair by experienced surgeons.

5-Fluorouracil upregulates cell surface B7-H1 (PD-L1) expression in gastrointestinal cancers.

BACKGROUND: Resistance to chemotherapy is a major obstacle in the effective treatment of cancer patients. B7-homolog 1, also known as programmed death ligand-1 (PD-L1), is an immunoregulatory protein that is overexpressed in several human cancers. Interaction of B7-H1 with programmed death 1 (PD-1) prevents T-cell activation and proliferation, sequestering the T-cell receptor from the cell membrane, inducing T-cell apoptosis, thereby leading to cancer immunoresistance. B7-H1 upregulation contributes to chemoresistance in several types of cancer, but little is known with respect to changes associated with 5-fluorouracil (5-FU) or gastrointestinal cancers. METHODS: HCT 116 p53+/+, HCT 116 p53-/- colorectal cancer (CRC) and OE33 esophageal adenocarcinoma (EAC) cells were treated with increasing doses of 5-FU (0.5 uM, 5 uM, 50 uM, 500 uM) or interferon gamma (IFN-γ, 10 ng/mL) in culture for 24 h and B7-H1 expression was quantified using flow cytometry and western blot analysis. We also evaluated B7-H1 expression, by immunohistochemistry, in tissue collected prior to and following neoadjuvant therapy in 10 EAC patients. RESULTS: B7-H1 expression in human HCT 116 p53+/+ and HCT 116 p53-/- CRC cells lines, while low at baseline, can be induced by treatment with 5-FU. OE33 baseline B7-H1 expression exceeded CRC cell maximal expression and could be further increased in a dose dependent manner following 5-FU treatment in the absence of immune cells. We further demonstrate tumor B7-H1 expression in esophageal adenocarcinoma patient-derived pre-treatment biopsies. While B7-H1 expression was not enhanced in post-treatment esophagectomy specimens, this may be due to the limits of immunohistochemical quantification. CONCLUSIONS: B7-H1/PD-L1 expression can be increased following treatment with 5-FU in gastrointestinal cancer cell lines, suggesting alternative mechanisms to classic immune-mediated upregulation. This suggests that combining 5-FU treatment with PD-1/B7-H1 blockade may improve treatment in patients with gastrointestinal adenocarcinoma.

Cancer Recurrence After Esophagectomy: Impact of Postoperative Infection in Propensity-Matched Cohorts.

BACKGROUND: Postoperative infection increases cancer recurrence and worsens survival in colorectal cancer, but the relationship for esophagogastric adenocarcinoma after esophagectomy is not well defined. We aimed to determine whether recurrence and survival after minimally invasive esophagectomy for esophagogastric adenocarcinoma were influenced by postoperative infection using propensity-matched analysis. METHODS: We abstracted data for 810 patients (1997-2010) and defined exposure as at least 1 in-hospital or 30-day infectious complication (n = 206 [25%]). Using 29 pretreatment/intraoperative variables, patients were propensity-score matched (caliper = 0.05). Time to cancer recurrence and survival (Kaplan-Meier curves and the Breslow test), and associated factors (Cox regression with shared frailty) were assessed. RESULTS: After propensity matching (n = 167 pairs), median bias across propensity-score variables was reduced from 12.9% (p < 0.001) to 4.4% (p = 1.000). Postoperative infection was not associated with rate (n = 60 versus 63; McNemar p = 0.736) or time to recurrence in those in whom disease recurred (median, 10.7 versus 11.1 months; Wilcoxon signed-rank p = 0.455) but was associated with shorter overall survival (n = 124 versus 102 deaths; median, 26 versus 41 months; Breslow p = 0.002). After adjusting for age, body mass index, neoadjuvant therapy, sex, comorbidity score, positive resection margins, pathologic stage, R0 resection, and recurrence, postoperative infection was associated with a 44% greater hazard for death (hazard ratio, 1.44; 95% confidence interval, 1.10-1.89). CONCLUSIONS: In patients with esophagogastric adenocarcinoma, infections after esophagectomy were not associated with an increased rate or earlier time to recurrence when baseline characteristics associated with infection risk were balanced using propensity-score matching. Despite this, overall survival was shorter in patients with infectious complications. After adjusting for other important survival predictors, infections after esophagectomy continued to be independently associated with worse survival.

Propensity-score analysis in thoracic surgery: When, why, and an introduction to how.

Propensity score matching is a valuable tool for dealing with observational data and nonrandom treatment assignment, which often results in groups that differ systematically in numerous measured and unmeasured variables. When these systematically different variables are associated with both group assignment and the outcome(s) of interest, bias is introduced. Propensity score matching assigns a propensity for group assignment, which is then used to create 2 groups that are balanced across all possible variables that might influence exposure assignment. When used in the proper conditions, these analytics allow for more accurate and precise estimates of risk for a variety of outcomes.