Gastric Extent of Tumor Predicts Peritoneal Metastasis in Siewert II Adenocarcinoma.

BACKGROUND: Whereas current guidelines recommend staging laparoscopy for most patients with potentially resectable gastric cancer, such a recommendation for patients with adenocarcinoma of the gastroesophageal junction (AEG) is lacking. This study sought to identify baseline clinicopathologic characteristics associated with peritoneal metastasis (PM) among patients with Siewert II AEG. METHODS: Trimodality therapy-eligible patients with Siewert II AEG (2000-2015, single institution) were retrospectively identified. A composite PM outcome was defined as follows: (1) PM at staging laparoscopy; (2) PM diagnosed during neoadjuvant chemoradiation; or (3) PM ≤6 months postoperatively. Logistic regression was used to identify features associated with PM; bootstrapped analysis (Youden J) identified the distal tumor extension that best discriminated the composite outcome. RESULTS: Of 188 patients, a composite PM outcome was observed in 26 of 188 (13.8%); 12 of 26 had positive staging laparoscopy, 10 of 26 experienced PM during chemoradiation, and 4 of 26 had PM ≤6 months postoperatively. Tumor extension below the GEJ was greater in patients with PM (median, 4.0 cm [interquartile range, 3.0-5.0] vs 3.0 cm [interquartile range, 2.0-3.0]; P < .001). All patients with PM had cT3 to cT4 tumors. Among patients with cT3 to cT4 tumors (n = 168 of 188; 89.4%), distal tumor extent (odds ratio, 1.67/cm; 95% CI, 1.23-2.28; P = .001) was independently associated with increased odds of PM. Gastric tumor extension ≥4 cm remained independently associated with PM (OR, 5.14; 95% CI, 2.11-12.53; P < .001) after adjustment for signet ring cell status. CONCLUSIONS: Distal tumor extent beyond the GEJ is independently associated with increased odds of PM in patients with Siewert II AEG. Patients with extensive gastric involvement should therefore be considered for staging laparoscopy before trimodality therapy.

Identification of Colorectal Cancer Cell Stemness from Single-Cell RNA Sequencing.

Cancer stem cells (CSC) play a critical role in metastasis, relapse, and therapy resistance in colorectal cancer. While characterization of the normal lineage of cell development in the intestine has led to the identification of many genes involved in the induction and maintenance of pluripotency, recent studies suggest significant heterogeneity in CSC populations. Moreover, while many canonical colorectal cancer CSC marker genes have been identified, the ability to use these classical markers to annotate stemness at the single-cell level is limited. In this study, we performed single-cell RNA sequencing on a cohort of 6 primary colon, 9 liver metastatic tumors, and 11 normal (nontumor) controls to identify colorectal CSCs at the single-cell level. Finding poor alignment of the 11 genes most used to identify colorectal CSC, we instead extracted a single-cell stemness signature (SCS_sig) that robustly identified "gold-standard" colorectal CSCs that expressed all marker genes. Using this SCS_sig to quantify stemness, we found that while normal epithelial cells show a bimodal distribution, indicating distinct stem and differentiated states, in tumor epithelial cells stemness is a continuum, suggesting greater plasticity in these cells. The SCS_sig score was quite variable between different tumors, reflective of the known transcriptomic heterogeneity of CRC. Notably, patients with higher SCS_sig scores had significantly shorter disease-free survival time after curative intent surgical resection, suggesting stemness is associated with relapse. IMPLICATIONS: This study reveals significant heterogeneity of expression of genes commonly used to identify colorectal CSCs, and identifies a novel stemness signature to identify these cells from scRNA-seq data.

ANPEP/CD13 Expression as a Marker of Lymphovascular Invasion and Survival in Esophageal Adenocarcinoma.

BACKGROUND: The presence of lymphovascular invasion (LVI) in early esophageal adenocarcinoma (EAC) is associated with more aggressive disease. Molecular markers associated with LVI are still largely unknown. Using a combination of transcriptomic analysis and validation experiments, we sought to describe markers for LVI and survival. METHODS: We performed NanoString expression profiling using RNA from 60 EAC specimens collected from surgery-only cases between 2000 and 2012. Differentially expressed genes (DEGs) were correlated with pathologic characteristics (T and N status and presence of LVI). Kaplan-Meier and Cox regression analyses were used to correlate gene expression with overall survival. Expression of alanyl aminopeptidase, membrane (ANPEP)/CD13 was validated by immunohistochemistry (IHC) in EAC tissue microarray and in EAC cell lines. RESULTS: We identified >20 up-regulated DEGs in tumor samples containing LVI. Multivariable analysis showed depth of invasion and ANPEP/CD13 expression were independently associated with overall survival, whereas nodal status was not. IHC analysis demonstrated overexpression of the ANPEP/CD13 protein in dysplastic Barrett esophagus and EAC tumors. Kaplan-Meier analysis showed that patients with higher RNA expression and strongly positive ANPEP/CD13 membrane IHC-Histoscore staining have shorter survival (P = .002). Down-regulation of ANPEP/CD13 expression by short hairpin RNA vector reduces colony formation, migration, and invasion of FLO-1 EAC cells. Overexpression of CD13 in SKGT4 EAC cells increases colony formation, motility, and invasion in vitro. CONCLUSIONS: Elevated expression of ANPEP/CD13 indicates shorter survival of EAC patients and a more invasive phenotype of cancer cells in vitro. Validation in a larger sample group is required to better understand the clinical significance of ANPEP/CD13 and other candidate genes.

New Insights into Macrophage Polarization and its Prognostic Role in Patients with Colorectal Cancer Liver Metastasis.

Background: As liver metastasis is the most common cause of mortality in patients with colorectal cancer, studying colorectal cancer liver metastasis (CLM) microenvironment is essential for improved understanding of tumor biology and to identify novel therapeutic targets. Methods: We used multiplex immunofluorescence platform to study tumor associated macrophage (TAM) polarization and adaptive T cell subtypes in tumor samples from 105 CLM patients (49 without and 56 with preoperative chemotherapy). Results: CLM exhibited M2 macrophage polarization, and helper T cells were the prevalent adaptive T cell subtype. The density of total, M2 and TGFß-expressing macrophages, and regulatory T cells was lower in CLM treated with preoperative chemotherapy. CLM with right-sided primary demonstrated enrichment of TGFß-expressing macrophages, and with left-sided primary had higher densities of helper and cytotoxic T cells. In multivariate analysis, high density of M2 macrophages correlated with longer recurrence-free survival (RFS) in the entire cohort [hazard ratio (HR) 0.425, 95% CI 0.219-0.825, p=0.011) and in patients without preoperative chemotherapy (HR 0.45, 95% CI 0.221-0.932, p=0.032). High pSMAD3-expressing macrophages were associated with shorter RFS in CLM after preoperative chemotherapy. Conclusions: Our results highlight the significance of a multi-marker approach to define the macrophage subtypes and identify M2 macrophages as a predictor of favorable prognosis in CLM.

Exploratory study of macrophage polarization and spatial distribution in colorectal cancer liver metastasis: a pilot study.

Background: The liver is the most typical site of metastatic disease for patients with colorectal cancer (CRC), and up to half the patients with CRC will develop colorectal liver metastasis (CLM). Studying the tumor microenvironment, particularly macrophages and their spatial distribution, can give us critical insight into treatment. Methods: Ten CLMs (five treatment-naïve and five post-neoadjuvant chemotherapy) were stained with multiplex immunofluorescence panels against cytokeratins, CD68, Arg1, CD206, CD86, CD163, PD-L1, and MRP8-14. Densities of cell phenotypes and their spatial distribution in the tumor center and the normal liver-tumor interface were correlated with clinicopathological variables. Results: M2 macrophages were the predominant subtype in both the tumor center and the periphery, with a relatively higher density at the periphery. The larger tumors, more than 3.9 cm, were associated with higher densities of total CD68+ macrophages and CD68+CD163+ CD206neg and CD68+CD206+ CD163neg M2 macrophage subtypes. Total macrophages in the tumor periphery demonstrated significantly greater proximity to malignant cells than did those in the tumor center (p=0.0371). The presence of higher than median CD68+MRP8-14+CD86neg M1 macrophages in the tumor center was associated with poor overall survival (median 2.34 years) compared to cases with lower than median M1 macrophages at the tumor center (median 6.41 years) in univariate analysis. Conclusion: The dominant polarization of the M2 macrophage subtype could drive new therapeutic approaches in CLM patients.

TP53 Alteration and Its Effect on Pathologic Response Are Associated with Survival after Resection of Colorectal Liver Metastases.

The aims of this study were to assess the effect of known gene alterations (RAS, TP53, APC, SMAD4, BRAF, and FBXW7) on pathologic response (PR) and their combined association with survival in patients with colorectal liver metastases (CLM). From a prospectively maintained database, we collected data on 458 patients who underwent curative-intent hepatectomy after receiving the first-line preoperative chemotherapy between 2004 and 2020. Major PR was defined as tumor viability of less than 50% in all tumors. Multivariate logistic regression revealed that oxaliplatin-containing regimen (OR: 2.54, 95% CI: 1.58-4.07, P < 0.001), bevacizumab-containing regimen (OR: 2.15, 95%CI: 1.36-3.39, P = 0.001), and TP53 alteration (OR: 0.42, 95%CI: 0.27-0.66, P < 0.001) were independently associated with major PR. Multivariate Cox regression also revealed that patients with TP53 wild-type and major PR (HR: 0.49, 95%CI: 0.31-0.77, P = 0.002) and those with TP53 alteration and major PR (HR: 0.70, 95%CI: 0.49-1.00, P = 0.048) had significantly better overall survival compared to those with minor PR. Further studies targeting the association of TP53 with PR and survival can help clarify the role of TP53 in CLM.

Spatial molecular and cellular determinants of STAT3 activation in liver fibrosis progression in non-alcoholic fatty liver disease.

Background & Aims: The prevalence of non-alcoholic fatty liver disease (NAFLD) and its severe form, non-alcoholic steatohepatitis (NASH), is increasing. Individuals with NASH often develop liver fibrosis and advanced liver fibrosis is the main determinant of mortality in individuals with NASH. We and others have reported that STAT3 contributes to liver fibrosis and hepatocellular carcinoma in mice. Methods: Here, we explored whether STAT3 activation in hepatocyte and non-hepatocyte areas, measured by phospho-STAT3 (pSTAT3), is associated with liver fibrosis progression in 133 patients with NAFLD. We further characterized the molecular and cellular determinants of STAT3 activation by integrating spatial distribution and transcriptomic changes in fibrotic NAFLD livers.Results: pSTAT3 scores in non-hepatocyte areas progressively increased with fibrosis severity (r = 0.53, p <0.001). Correlation analyses between pSTAT3 scores and expression of 1,540 immune- and cancer-associated genes revealed a large effect of STAT3 activation on gene expression changes in non-hepatocyte areas and confirmed a major role for STAT3 activation in fibrogenesis. Digital spatial transcriptomic profiling was also performed on 13 regions selected in hepatocyte and non-hepatocyte areas from four NAFLD liver biopsies with advanced fibrosis, using a customized panel of markers including pSTAT3, PanCK+CK8/18, and CD45. The regions were further segmented based on positive or negative pSTAT3 staining. Cell deconvolution analysis revealed that activated STAT3 was enriched in hepatic progenitor cells (HPCs) and sinusoidal endothelial cells. Regression of liver fibrosis upon STAT3 inhibition in mice with NASH resulted in a reduction of HPCs, demonstrating a direct role for STAT3 in HPC expansion. Conclusion: Increased understanding of the spatial dependence of STAT3 signaling in NASH and liver fibrosis progression could lead to novel targeted treatment approaches. Impact and implications: Advanced liver fibrosis is the main determinant of mortality in patients with NASH. This study showed using liver biopsies from 133 patients with NAFLD, that STAT3 activation in non-hepatocyte areas is strongly associated with fibrosis severity, inflammation, and progression to NASH. STAT3 activation was enriched in hepatic progenitor cells (HPCs) and sinusoidal endothelial cells (SECs), as determined by innovative technologies interrogating the spatial distribution of pSTAT3. Finally, STAT3 inhibition in mice resulted in reduced liver fibrosis and depletion of HPCs, suggesting that STAT3 activation in HPCs contributes to their expansion and fibrogenesis in NAFLD.

Colorectal Liver Micrometastases: Association with RAS/TP53 Co-Mutation and Prognosis after Surgery.

BACKGROUND: Micrometastases, defined as microscopic cancer cells spatially separated from the macroscopically evident metastasis, are identified in 24% to 56% of resected colorectal liver metastases (CLMs). Somatic gene mutations have emerged as independent prognostic factors in CLM. This study aimed to determine the prognostic impact and risk factors for the presence of micrometastases, including somatic gene mutations. STUDY DESIGN: Prospective evaluation for micrometastases was performed at 2 centers in the US and France from 2015 to 2019. CLM specimens were cut radially from the tumor margin to surrounding grossly normal liver for a distance of 2 cm. Depending on CLM size, 3 to 8 specimens per patient were submitted for microscopic analysis. Somatic gene mutations were detected by next-generation sequencing. RESULTS: Among 140 patients undergoing CLM resection in the US (n = 84) and France (n = 56), 36 (26%) patients were found to have micrometastases. Five-year overall and recurrence-free survival rates with micrometastases were 39% and 0%, respectively, compared with 61% and 20% without micrometastases (both p < 0.05). In multivariable analyses, the presence of micrometastases was an independent risk factor for worse overall survival (hazard ratio 2.88, 95% CI 1.46 to 5.70, p = 0.002) and recurrence-free survival (hazard ratio 1.56, 95% CI 1.01 to 2.41, p = 0.046). In binary logistic regression analysis, RAS/TP53 co-mutation was found to significantly increase the risk of micrometastases (odds ratio 2.77, 95% CI 1.15 to 6.71, p = 0.024). CONCLUSIONS: Micrometastases are associated with significantly worse survival after CLM resection. RAS/TP53 co-mutation correlated with increased risk of micrometastases. Further studies are needed to determine strategies to eradicate micrometastases.

Salvage Esophagectomy Definition Influences Comparative Outcomes in Esophageal Squamous Cell Cancers.

BACKGROUND: In retrospective studies the definition of salvage esophagectomy has been inconsistent and is a source of bias. We sought to describe how variability in the definition of salvage affects comparative outcomes of trimodality therapy (TMT) and bimodality therapy (BMT). METHODS: Patients with locally advanced esophageal squamous cell carcinoma who completed chemoradiation therapy (CRT) from 2002 to 2017 were identified. TMT included patients who had a planned esophagectomy after CRT. BMT included patients treated with CRT only plus salvage esophagectomy, variably defined as an esophagectomy occurring (A) 3 months after CRT; (B) 3 months after CRT, excluding delayed recovery; (C) 3 months after CRT, excluding delayed workup; or (D) 6 months after CRT. Long-term survival outcomes between the TMT and BMT groups were compared for each definition of salvage esophagectomy. Time to surgery was included a priori in a multivariable model for overall survival. RESULTS: Of 143 patients, 90 (63%) underwent esophagectomy and 53 (37%) received CRT only. Although the total patients remained the same, the composition of the TMT and BMT groups varied by salvage definitions A through D. Various definitions resulted in different 5-year survival rates for TMT vs BMT groups: (A) 56% vs 39%, (B) 61% vs 34%, (C) 50% vs 42%, and (D) 51% vs 39%. In a Cox multivariable analysis age and proximal/middle esophageal tumors were associated with worse postoperative survival, but time to surgery was not. CONCLUSIONS: Slight variations in the definition of salvage esophagectomy can influence the interpretation of TMT and BMT outcomes. Future studies should consistently define treatment groups.

A phase II randomized double blinded trial evaluating the efficacy of curcumin with pre-operative chemoradiation for rectal cancer.

Background: In vivo studies demonstrate that curcumin increases radioresponse of colorectal cancers. To demonstrate efficacy in humans, we performed a randomized double-blind study of locally advanced rectal cancer (LARC) patients receiving pre-operative chemoradiation therapy (CRT) ± curcumin. We used pathologic complete response (pCR) rate as a surrogate for clinical outcome. Methods: From 2008-2010, LARC patients were randomized to placebo/curcumin in a 1:2 ratio. Patients received CRT [50.4 gray in 28 fractions; capecitabine (825 mg/m2 twice daily)] followed by surgery. Curcumin (4 grams orally, twice daily) or placebo was given throughout CRT and 6 weeks afterward. Toxicity was monitored weekly. Blood samples taken pre- and 1-hour post-ingestion and tissue biopsies (both collected at CRT week 2) were analyzed for pharmacokinetics. The primary outcome was surgical pCR rate. Results: Of 22 enrolled patients, 15 received curcumin. Median age was 61 years and the majority were male (n=13; 59%). The median serum curcumin concentrations before (3.04 ng/mL; range, 1.24-18.88 ng/mL) and 1 hour after (3.32 ng/mL; range, 0.84-5.36 ng/mL) curcumin intake did not differ significantly (P=0.33). Serum curcumin concentrations both increased and decreased 1-hour post-administration (range as percentage of baseline: 8.8-258.1%). Twelve curcumin patient tissue biopsies had median curcumin concentration of 33.7 ng/mg tissue (range, 0.1-4,765.7 ng/mg). Two placebo and 1 curcumin patient achieved pCRs (P=0.18). One grade 3 toxicity (infection) was experienced. Conclusions: The addition of curcumin to CRT did not increase pCR rates for LARC patients. The unpredictable bioavailability of curcumin contributes to continued uncertainties regarding curcumin efficacy. Trial Registration: ClinicalTrials.gov identifier: NCT00745134.

Efficacy, Safety, and Biomarker Analysis of Combined PD-L1 (Atezolizumab) and VEGF (Bevacizumab) Blockade in Advanced Malignant Peritoneal Mesothelioma.

Malignant peritoneal mesothelioma (MPeM) is a rare but aggressive malignancy with limited treatment options. VEGF inhibition enhances efficacy of immune-checkpoint inhibitors by reworking the immunosuppressive tumor milieu. Efficacy and safety of combined PD-L1 (atezolizumab) and VEGF (bevacizumab) blockade (AtezoBev) was assessed in 20 patients with advanced and unresectable MPeM with progression or intolerance to prior platinum-pemetrexed chemotherapy. The primary endpoint of confirmed objective response rate per RECISTv1.1 by independent radiology review was 40% [8/20; 95% confidence interval (CI), 19.1-64.0] with median response duration of 12.8 months. Six (75%) responses lasted for >10 months. Progression-free and overall survival at one year were 61% (95% CI, 35-80) and 85% (95% CI, 60-95), respectively. Responses occurred notwithstanding low tumor mutation burden and PD-L1 expression status. Baseline epithelial-mesenchymal transition gene expression correlated with therapeutic resistance/response (r = 0.80; P = 0.0010). AtezoBev showed promising and durable efficacy in patients with advanced MPeM with an acceptable safety profile, and these results address a grave unmet need for this orphan disease. SIGNIFICANCE: Efficacy of atezolizumab and bevacizumab vis-à-vis response rates and survival in advanced peritoneal mesothelioma previously treated with chemotherapy surpassed outcomes expected with conventional therapies. Biomarker analyses uncovered epithelial-mesenchymal transition phenotype as an important resistance mechanism and showcase the value and feasibility of performing translationally driven clinical trials in rare tumors.See related commentary by Aldea et al., p. 2674.This article is highlighted in the In This Issue feature, p. 2659.

Pilot Clinical Trial of Perioperative Durvalumab and Tremelimumab in the Treatment of Resectable Colorectal Cancer Liver Metastases.

PURPOSE: Despite the prognostic importance of immune infiltrate in colorectal cancer, immunotherapy has demonstrated limited clinical activity in refractory metastatic proficient mismatch-repair (pMMR) colorectal cancer. This study explores combining anti-CTLA-4 and an anti-PD-L1 therapy in the preoperative management of resectable colorectal cancer liver metastases with the intent to improve immune responses in this disease setting. PATIENTS AND METHODS: Patients with resectable colorectal cancer liver-only metastases received one dose of tremelimumab and durvalumab preoperatively followed by single-agent durvalumab postoperatively. Primary objectives were to determine feasibility and safety. RESULTS: A total of 24 patients were enrolled between November 2016 and November 2019. Twenty-three patients received treatment [21 pMMR and 2 deficient mismatch-repair (dMMR)] and subsequently 17 (74%; 95% CI: 53%-88%) underwent surgical resection. Grade 3/4 treatment-related immune toxicity and postoperative grade 3/4 toxicity were seen in 5/23 (22%; 95% CI: 10%-44%) and 2/17 (12%; 95% CI: 2%-38%) patients. The median relapse-free survival (RFS) was 9.7 (95% CI: 8.1-17.8) months, and overall survival was 24.5 (95% CI: 16.5-28.4) months. Four patients demonstrated complete pathologic response, two dMMR patients and two POLE mutation patients. Pre- and post-tumor tissue analysis by flow cytometry, immunofluorescence, and RNA sequencing revealed similar levels of T-cell infiltration, but did demonstrate evidence of CD8+ and CD4+ activation posttreatment. An increase in B-cell transcriptome signature and B-cell density was present in posttreatment samples from patients with prolonged RFS. CONCLUSIONS: This study demonstrates the safety of neoadjuvant combination tremelimumab and durvalumab prior to colorectal cancer liver resection. Evidence for T- and B-cell activation following this therapy was seen in pMMR metastatic colorectal cancer.

ARID1A Mutation May Define an Immunologically Active Subgroup in Patients with Microsatellite Stable Colorectal Cancer.

PURPOSE: AT-rich interactive domain 1A (ARID1A) is commonly mutated in colorectal cancer, frequently resulting in truncation and loss of protein expression. ARID1A recruits MSH2 for mismatch repair during DNA replication. ARID1A deficiency promotes hypermutability and immune activation in preclinical models, but its role in patients with colorectal cancer is being explored. EXPERIMENTAL DESIGN: The DNA sequencing and gene expression profiling of patients with colorectal cancer were extracted from The Cancer Genome Atlas and MD Anderson Cancer Center databases, with validation utilizing external databases, and correlation between ARID1A and immunologic features. IHC for T-cell markers was performed on a separate cohort of patients. RESULTS: Twenty-eight of 417 patients with microsatellite stable (MSS) colorectal cancer (6.7%) had ARID1A mutation. Among 58 genes most commonly mutated in colorectal cancer, ARID1A mutation had the highest increase with frameshift mutation rates in MSS cases (8-fold, P < 0.001). In MSS, ARID1A mutation was enriched in immune subtype (CMS1) and had a strong correlation with IFNγ expression (Δz score +1.91, P < 0.001). Compared with ARID1A wild-type, statistically significant higher expression for key checkpoint genes (e.g., PD-L1, CTLA4, and PDCD1) and gene sets (e.g., antigen presentation, cytotoxic T-cell function, and immune checkpoints) was observed in mutant cases. This was validated by unsupervised differential expression of genes related to immune response and further confirmed by higher infiltration of T cells in IHC of tumors with ARID1A mutation (P = 0.01). CONCLUSIONS: The immunogenicity of ARID1A-mutant cases is likely due to an increased level of neoantigens resulting from increased tumor mutational burden and frameshift mutations. Tumors with ARID1A mutation may be more susceptible to immune therapy-based treatment strategies and should be recognized as a unique molecular subgroup in future immune therapy trials.

Frequency and Implications of Paratracheal Lymph Node Metastases in Resectable Esophageal or Gastroesophageal Junction Adenocarcinoma.

OBJECTIVE: We aimed to evaluate the frequency of paratracheal lymph nodes (LN) metastases and their prognostic influence. SUMMARY BACKGROUND DATA: Paratracheal LNs are considered regional nodes in the esophageal cancer classification, but their metastatic rate and influence on survival remain unclear. METHODS: One thousand one hundred ninety-nine patients with resectable esophageal or gastroesophageal junction adenocarcinoma (EAC) (January 2002 and December 2016) in our Gastrointestinal Medical Oncology Database were analyzed. Paratracheal LNs were defined as1R, 1L, 2R, 2L, 4R, and 4L, according to the 8th American Joint Committee on Cancer classification. RESULTS: Of 1199 patients, 73 (6.1%) had positive paratracheal LNs at diagnosis. The median overall survival (OS) of 73 patients with initial paratracheal LN involvement was 2.10 years (range 0.01-10.1, 5-yrs OS 24.2%). Of 1071 patients who were eligible for recurrence evaluation, 70 patients (6.5%) developed paratracheal LN metastases as the first recurrence. The median time to recurrence was 1.28 years (range 0.28-5.96 yrs) and the median OS following recurrence was only 0.95 year (range 0.03-7.88). OS in 35 patients who had only paratracheal LN recurrence was significantly longer than in patients who had other recurrences (median OS 2.26 vs 0.51 yrs, 5-yrs OS; 26.8% vs 0%, P < 0.0001). Higher T stage (T3/T4) was an independently risk factor for paratracheal LN recurrence (odds ratio 5.10, 95% confidence interval 1.46-17.89). We segregated patients in 3 groups based on the distance of tumor's proximal edge to esophagogastric junction (low; ≤2 cm, medium; 2.0-7.0 cm, and high; >7.0 cm). Paratracheal LN metastases were more frequent with the proximal tumors (low, 4.2%; medium, 12.0%; high, 30.3%; Cochran-Armitage Trend test, P < 0.001). CONCLUSION: Paratracheal LN metastases were associated with a shorter survival in resectable EAC patients. Alternate approaches to prolong survival of this group of patients are warranted.

Modified En Bloc Esophagectomy Compared With Standard Resection After Neoadjuvant Chemoradiation.

BACKGROUND: Surgeons have shifted away from the practice of en bloc esophagectomy, particularly in the era of neoadjuvant therapies. Although some still advocate for this radical approach, contemporary data establishing its superiority are sparse. We hypothesized that a more complete, radical resection could be completed in the setting of chemoradiation without adding morbidity. METHODS: Patients undergoing esophagectomy after neoadjuvant chemoradiation for esophageal adenocarcinoma from 2006-2018 were evaluated. Outcomes after right transthoracic en bloc esophagectomy were compared with standard esophagectomy to determine the impact on outcomes. A Cox proportional hazard model was evaluated, and logistic regression was performed to determine the impact of en bloc resection on postoperative morbidity. RESULTS: A total of 604 patients were identified, including 133 (22%) who underwent modified en bloc esophagectomy. Positive margins were most likely to occur in standard esophagectomy (35 of 471, 7%) vs en bloc (3 of 133, 2%) (P = .026). En bloc resection yielded a greater lymph node harvest (27; interquartile range, 22-36), as compared to standard esophagectomy (22; interquartile range, 17-28), P < .001. Multivariable analysis demonstrated prolonged progression-free survival with en bloc resection (hazard ratio, 0.74; P = .041), with 3-year freedom from locoregional recurrences of 78% and 90% for standard and en bloc approaches (P = .044). There were no differences in cardiopulmonary, gastrointestinal, or wound complications, as well as leak or chylothorax. CONCLUSIONS: Our experience demonstrates improved locoregional disease control with en bloc esophagectomy, with equivalent morbidity. Although these results may be multifactorial, including adequate clearance of both primary tumor and nodal micrometastases, this approach is safe and feasible.

Development and Validation of a Gene Signature Classifier for Consensus Molecular Subtyping of Colorectal Carcinoma in a CLIA-Certified Setting.

PURPOSE: Consensus molecular subtyping (CMS) of colorectal cancer has potential to reshape the colorectal cancer landscape. We developed and validated an assay that is applicable on formalin-fixed, paraffin-embedded (FFPE) samples of colorectal cancer and implemented the assay in a Clinical Laboratory Improvement Amendments (CLIA)-certified laboratory. EXPERIMENTAL DESIGN: We performed an in silico experiment to build an optimal CMS classifier using a training set of 1,329 samples from 12 studies and validation set of 1,329 samples from 14 studies. We constructed an assay on the basis of NanoString CodeSets for the top 472 genes, and performed analyses on paired flash-frozen (FF)/FFPE samples from 175 colorectal cancers to adapt the classifier to FFPE samples using a subset of genes found to be concordant between FF and FFPE, tested the classifier's reproducibility and repeatability, and validated in a CLIA-certified laboratory. We assessed prognostic significance of CMS in 345 patients pooled across three clinical trials. RESULTS: The best classifier was weighted support vector machine with high accuracy across platforms and gene lists (>0.95), and the 472-gene model outperforming existing classifiers. We constructed subsets of 99 and 200 genes with high FF/FFPE concordance, and adapted FFPE-based classifier that had strong classification accuracy (>80%) relative to "gold standard" CMS. The classifier was reproducible to sample type and RNA quality, and demonstrated poor prognosis for CMS1-3 and good prognosis for CMS2 in metastatic colorectal cancer (P < 0.001). CONCLUSIONS: We developed and validated a colorectal cancer CMS assay that is ready for use in clinical trials, to assess prognosis in standard-of-care settings and explore as predictor of therapy response.

Esophageal adenocarcinoma with any component of signet ring cells portends poor prognosis and response to neoadjuvant therapy.

BACKGROUND: Multiple investigations have shown inferior outcomes for esophageal cancer patients with signet ring cell (SRC) histology. Traditionally, SRC adenocarcinoma has been defined by ≥50% of the tumor composed of SRC. We hypothesized that patients with SRC even <50% would show resistance to standard multimodality therapy with poorer long-term outcomes. METHODS: Patients treated with trimodality therapy for adenocarcinoma from 2006 to 2018 were evaluated for SRC on pretreatment biopsy specimens. Available hematoxylin and eosin slides containing SRC tumors were re-reviewed by an esophageal pathologist to quantify the percent composition of SRC. RESULTS: SRC histology was identified on at least 1 pathologic specimen in 106 of 819 (13%) patients. Rates of pathologic complete response (pCR) among usual-type and SRC tumors were 25% (177/713) and 10% (11/106), respectively (P = .006). The pretreatment SRC components did not independently affect the rate of pCR (1%-10% SRC: 4% [2/46] pCR; 11%-49% SRC: 25% [7/28] pCR; 50%-100% SRC: 7% [2/30] pCR). Kaplan-Meier analysis demonstrated worse survival among patients with any degree of SRC present on pretreatment biopsy, as compared with usual-type esophageal adenocarcinoma (P < .0001). Cox multivariable analysis failed to identify a relationship between increasing SRC component and poorer survival. CONCLUSIONS: We present the only known evaluation of the percentage of SRC component in esophageal carcinoma. Our data support the hypothesis that esophageal adenocarcinoma with any component of SRC are more resistant to chemoradiation with poorer survival. Pathologic reporting of esophageal adenocarcinoma should include any component of SRC. Alternative therapies in patients with any SRC component may be indicated.

Total Lesion Glycolysis Assessment Identifies a Patient Fraction With a High Cure Rate Among Esophageal Adenocarcinoma Patients Treated With Definitive Chemoradiation.

OBJECTIVE: We aimed to determine whether tumor metabolism could be prognostic of cure in L-EAC patients who receive definitive chemoradiation. SUMMARY BACKGROUND DATA: Patients with inoperable localized esophageal adenocarcinoma (L-EAC) often receive definitive chemoradiation; however, biomarkers and/or imaging variables to prognosticate cure are missing. METHODS: Two hundred sixty-six patients with L-EAC who had chemoradiation but not surgery were analyzed from the prospectively maintained EAC databases in the Department of Gastrointestinal Medical Oncology at The University of Texas MD Anderson Cancer Center (Texas, USA) between March 2002 and April 2015. Maximum standardized uptake value (SUVmax) and total lesion glycolysis (TLG) from the positron emission tomography data were evaluated. RESULTS: Of 266 patients, 253 (95%) were men; the median age was 67 years (range 20-91 yrs) and 153 had poorly differentiated L-EAC. The median SUVmax was 10.3 (range 0-87) and the median TLG was 85.7 (range 0-3227). Both SUVmax and TLG were higher among those with: tumors >5 cm in length, high clinical stage, and high tumor and node categories by TNM staging (all P < 0.0001). Of 234 patients evaluable for cure, 60 (25.6%) achieved cure. In the multivariable logistic regression model, low TLG (but not low SUVmax) was associated with cure (continuous TLG value: odds ratio 0.70, 95% confidence interval (CI) 0.54-0.92). TLG was quantified into 4 quartile categorical variables; first quartile (Q1; <32), second quartile (Q2; 32.0-85.6), third quartile (Q3; 85.6-228.4), and fourth quartile (Q4; >228.4); the cure rate was only 10.3% in Q4 and 5.1% in Q3 but increased to 28.8% in Q2, and 58.6% in Q1. The cross-validation resulted in an average accuracy of prediction score of 0.81 (95% CI, 0.75-0.86). CONCLUSIONS: In this cross-validated model, 59% of patients in the 1st quartile were cured following definitive chemoradiation. Baseline TLG could be pursued as one of the tools for esophageal preservation.

Brain metastases in patients with upper gastrointestinal cancer is associated with proximally located adenocarcinoma and lymph node metastases.

BACKGROUND: As cancer patients are surviving longer, more patients manifest brain metastases (BRMs). However, the rate of BRMs from upper gastrointestinal cancer is unclear. We therefore evaluated the frequency and prognostic effect of BRMs in this setting. METHODS: We analyzed records of 2348 patients who were treated between January 2002 and December 2016 for upper gastrointestinal cancer, including esophageal and gastroesophageal junction adenocarcinoma (EAC; proximal EAC, Siewert types I and II), esophageal squamous cell carcinoma (ESCC), and gastric adenocarcinoma (GAC; Siewert type III and stomach cancer) in our Gastrointestinal Medical Oncology Database. Frequency, risk factors, and survival after BRMs were evaluated. RESULTS: Of 2348 patients, 68 (2.9%) had BRMs upon follow-up. The BRM rates were as follows: proximal EAC, 4.8%; Siewert type I, 5.9%; Siewert type II, 2.2%; Siewert type III, 0.7%; ESCC: 1.2%; and stomach cancer, 0%. Among EAC patients, Siewert type I and lymph node metastases were independent the risk factors for BRMs in the multivariable analysis. The median overall survival (OS) in the 68 patients with BRMs was only 1.16 years (95% CI 0.78-1.61). However, OS for patients who had a solitary BRM, who had BRM but no other distant metastasis, or who underwent surgery or stereotactic radiosurgery favorable. CONCLUSION: Patients with proximally located adenocarcinoma, or with lymph node metastases are at a higher risk for BRMs and patients fare better after treatment of isolated BRM.