Racial disparities in rates of invasiveness of resected intraductal papillary mucinous neoplasms in the United States

BACKGROUND

Racial and ethnic disparities have been observed in the multidisciplinary management of pancreatic ductal adenocarcinoma. Intraductal papillary mucinous neoplasm is the most common identifiable precursor to pancreatic ductal adenocarcinoma, where early surgical intervention before the development of an invasive intraductal papillary mucinous neoplasm improves survival. The association of race/ethnicity with the risk of identifying invasive intraductal papillary mucinous neoplasms during resection has not been previously defined.

METHODS

The American College of Surgeons National Quality Improvement Program targeted pancreatectomy database (2014-2021) was queried for patients with race/ethnicity data who underwent resection of an intraductal papillary mucinous neoplasm. Backward Wald logistic regression modeling (P ≤ 0.05 for entry; P > .10 for removal) was used to identify independent predictors of invasion.

RESULTS

A total of 4,505 cases of resected intraductal papillary mucinous neoplasms were identified, with 923 (20.5%) demonstrating invasive intraductal papillary mucinous neoplasms. The cohort of individuals other than non-Hispanic Whites were significantly more likely to have invasive intraductal papillary mucinous neoplasms (White, 19.9%; Black, 24.2%; Asian, 23.7%; Hispanic, 22.6%; P = .026). Such disparity could not be explained by greater comorbidity, as non-White patients were significantly younger (age <65 years: 41.7% vs 33.2%, P < .001) and had better physical status (American Society of Anesthesiologists score ≤2: 28.8% vs 25.2%, P = .053). After controlling for clinicodemographic variables, being an individual of race/ethnicity other than White was independently associated with higher odds of invasive intraductal papillary mucinous neoplasms (odds ratio, 1.280; 95% confidence interval, 1.046-1.566; P = .017). No differences in postoperative morbidity were observed.

CONCLUSION

In a national cohort of patients with resected intraductal papillary mucinous neoplasms, individuals who identified as being of race/ethnicity other than White were significantly more likely to have invasive intraductal papillary mucinous neoplasms during surgical resection.

Extent of Resection and Long-Term Outcomes for Appendiceal Adenocarcinoma: a SEER Database Analysis of Mucinous and non-Mucinous Histologies

BACKGROUND

Mucinous appendiceal adenocarcinomas (MAA) and non-mucinous appendiceal adenocarcinomas (NMAA) demonstrate differences in rates and patterns of recurrence, which may inform the appropriate extent of surgical resection (i.e., appendectomy versus colectomy). The impact of extent of resection on disease-specific survival (DSS) for each histologic subtype was assessed.

PATIENTS AND METHODS

Patients with resected, non-metastatic MAA and NMAA were identified in the Surveillance, Epidemiology, and End Results database (2000-2020). Multivariable models were created to examine predictors of colectomy for each histologic subtype. DSS was calculated using Kaplan-Meier estimates and examined using Cox proportional hazards modeling.

RESULTS

Among 4674 patients (MAA: n = 1990, 42.6%; NMAA: n = 2684, 57.4%), the majority (67.8%) underwent colectomy. Among colectomy patients, the rate of nodal positivity increased with higher T-stage (MAA: T1: 4.6%, T2: 4.0%, T3: 17.1%, T4: 21.6%, p < 0.001; NMAA: T1: 6.8%, T2: 11.4%, T3: 25.6%, T4: 43.8%, p < 0.001) and higher tumor grade (MAA: well differentiated: 7.7%, moderately differentiated: 19.2%, and poorly differentiated: 31.3%; NMAA: well differentiated: 9.0%, moderately differentiated: 20.5%, and 44.4%; p < 0.001). Nodal positivity was more frequently observed in NMAA (27.6% versus 16.4%, p < 0.001). Utilization of colectomy was associated with improved DSS for NMAA patients with T2 (log rank p = 0.095) and T3 (log rank p = 0.018) tumors as well as moderately differentiated histology (log rank p = 0.006). Utilization of colectomy was not associated with improved DSS for MAA patients, which was confirmed in a multivariable model for T-stage, grade, and use of adjuvant chemotherapy [hazard ratio (HR) 1.00, 95% confidence interval (CI) 0.81-1.22].

CONCLUSIONS

Colectomy was associated with improved DSS for patients with NMAA but not MAA. Colectomy for MAA may not be required.

Operative trends for pancreatic and hepatic malignancies during the COVID-19 pandemic

BACKGROUND

The COVID-19 pandemic disrupted routine health care, including many elective and non-cancer operations in the United States. Most hepato-pancreato-biliary malignancy patients require outpatient imaging, tissue sampling, and staging, and many undergo neoadjuvant therapy before operative intervention. The aims of this study were to evaluate the effect of the COVID-19 pandemic on hepato-pancreato-biliary oncologic operations and to determine whether trends in neoadjuvant therapy were altered by the pandemic.

METHODS

Adult patients in the United States undergoing oncologic operations for pancreatic, primary and secondary hepatic malignancies, with or without neoadjuvant therapy, were extracted from the Vizient Clinical Data Base. Control chart analysis was used to plot trends over time and to determine whether changes were statistically significant. Wilcoxon rank-sum tests also compared monthly operative volume from pre-pandemic (12 month) and pandemic (28 months) periods.

RESULTS

A total of 36,553 patients were identified over 40 months. Mean monthly pancreatic oncologic operations were unaffected by the pandemic (P = .257). Operations for pancreatic oncologic operations with prior neoadjuvant therapy increased throughout the pandemic (P = .002). Oncologic operations for primary and secondary hepatic malignancies were significantly reduced for 4 and 2 months, respectively, at the beginning of the pandemic but returned to their pre-pandemic baseline within 4 months (P = .169 and P = .598).

CONCLUSION

Pancreatic operation volumes for cancer did not change, but pancreatic operations after neoadjuvant therapy continued to increase during the pandemic. Operations for hepatic malignancy were transiently disrupted but quickly normalized. These observations suggest that surgery for hepato-pancreato-biliary malignancies was prioritized during the pandemic.

Does Hospital Operative Volume Influence the Outcomes of Patients After Heated Intraperitoneal Chemotherapy for Peritoneal Carcinomatosis?

BACKGROUND

For some cancer operations, center volume is associated with improved patient outcomes. Whether this association is true for cytoreductive surgery/heated intraperitoneal chemotherapy (CRS/HIPEC) is unclear. Given the rapidly expanding use of CRS/HIPEC, the aim of this analysis was to determine whether a volume-outcome relationship exists for this strategy.

METHODS

The Vizient Clinical Database® was queried for CRS/HIPEC cases from January 2020 through December 2022. Low-, medium-, and high-volume designations were made by sorting hospitals by case volume and creating equal tertiles based on total number of cases. Analysis was performed via one-way ANOVA with post-hoc Tukey test, as indicated.

RESULTS

In the 36-month study period, 5165 cases were identified across 149 hospitals. Low- (n = 113), medium- (n = 25), and high-volume (n = 11) centers performed a median of 4, 21, and 47 cases per annum, respectively. Most cases were performed for appendiceal (39.3%) followed by gynecologic neoplasms (20.4%). Groups were similar with respect to age, gender, race, comorbidities, and histology. Low-volume centers were more likely to utilize the ICU post-operatively (59.6% vs. 40.5% vs. 36.3%; p = 0.02). No differences were observed in morbidity (9.4% vs. 7.1% vs. 9.0%, p = 0.71), mortality (0.9% vs. 0.6% vs. 0.7%, p = 0.93), length of stay (9.3 vs. 9.4 vs. 10 days, p = 0.83), 30-day readmissions (5.6% vs. 5.6% vs. 5.6%, p = 1.0), or total cost among groups.

CONCLUSIONS

No association was found between CRS/HIPEC hospital volume and post-operative outcomes. These data suggest that in academic medical centers with HIPEC programs, outcomes for commonly treated cancers are not associated with hospital volume.

Recurrence-free survival dynamics following adjuvant chemotherapy for resected colorectal cancer: A systematic review of randomized controlled trials

BACKGROUND

Several cytotoxic chemotherapies have demonstrated efficacy in improving recurrence-free survival (RFS) following resection of Stage II-IV colorectal cancer (CRC). However, the temporal dynamics of response to such adjuvant therapy have not been systematically quantified.

METHODS

The Cochrane Central Register of Trials, Medline (PubMed) and Web of Science were queried from database inception to February 23, 2023 for Phase III randomized controlled trials (RCTs) where there was a significant difference in RFS between adjuvant chemotherapy and surgery only arms. Summary data were extracted from published Kaplan-Meier curves using DigitizeIT. Absolute differences in RFS event rates were compared at matched intervals using multiple paired t-tests.

RESULTS

The initial search yielded 1469 manuscripts. After screening, 18 RCTs were eligible (14 Stage II/III; 4 Stage IV), inclusive of 16,682 patients. In the absence of adjuvant chemotherapy, the greatest rate of recurrence was observed in the first year (mean RFS event rate; 0-0.5 years: 0.22 ± 0.21; 0.5-1 years: 0.20 ± 0.09). Adjuvant chemotherapy was associated with significant decreases in the RFS event rates for the intervals 0-0.5 years (0.09 ± 0.09 vs. 0.22 ± 0.21, p < 0.001) and 0.5-1 years (0.14 ± 0.11 vs. 0.20 ± 0.09, p = 0.001) after randomization, but not at later intervals (1-5 years). In Stage IV trials, RFS event rates significantly differed for the interval 0-0.5 years (p = 0.012), corresponding with adjuvant treatment durations of 6 months. In Stage II/III trials, which included therapies of 6-24 months duration, there were marked differences in the RFS event rates between surgery and chemotherapy arms for the intervals 0-0.5 years (p < 0.001) and 0.5-1 years (p < 0.001) with smaller differences in the RFS event rates for the intervals 1-2 years (p = 0.012) and 2-3 years (p = 0.010).

CONCLUSIONS

In a systematic review of positive RCTs comparing adjuvant chemotherapy to surgery alone for Stage II-IV CRC, observed RFS improvements were driven by early divergences that occurred primarily during active cytotoxic chemotherapy. Late recurrence dynamics were not influenced by adjuvant therapy use. Such observations may have implications for the use of chemotherapy for micrometastatic clones detectable by cell-free DNA-based methodologies.

Hepatic pseudotumor associated with Strongyloides infection: A case report

BACKGROUND

Strongyloides sterocoralis is a parasitic infection caused by a roundworm that is transmitted through soil contaminated with larvae. It can infrequently cause hepatic abscesses in immunocompromised patients and is rarely reported to form hepatic lesions in immunocompetent hosts.

CASE SUMMARY

We present a case study of a 45-year-old female who presented with right upper quadrant abdominal pain and constitutional symptoms for several weeks. Cross-sectional imaging identified several malignant-appearing liver masses. Further investigation, including serological testing and histopathologic examination, revealed the presence of serum Strongyloides antibodies and hepatic granulomas with extensive necrosis. Following treatment with ivermectin for 2 wk, there was complete resolution of the liver lesions and associated symptoms.

CONCLUSION

This case highlights the importance of considering parasitic infections, such as Strongyloides, in the differential diagnosis of hepatic masses. Early recognition and appropriate treatment can lead to a favorable outcome and prevent unnecessary invasive procedures. Increased awareness among clinicians is crucial to ensure the timely diagnosis and management of such cases.

Ampullary Adenocarcinoma: A Review of the Mutational Landscape and Implications for Treatment

Ampullary carcinomas represent less than 1% of all gastrointestinal malignancies with an incidence of approximately 6 cases per 1 million. Histologic examination and immunohistochemistry have been traditionally used to categorize ampullary tumors into intestinal, pancreatobiliary or mixed subtypes. Intestinal-subtype tumors may exhibit improved survival versus the pancreatobiliary subtype, although studies on the prognostic value of immunomorphologic classification have been inconsistent. Genomic classifiers hold the promise of greater reliability, while providing potential targets for precision oncology. Multi-institutional collaboration will be necessary to better understand how molecular classification can guide type and sequencing of multimodality therapy.

Association between SMAD4 Mutations and GATA6 Expression in Paired Pancreatic Ductal Adenocarcinoma Tumor Specimens: Data from Two Independent Molecularly-Characterized Cohorts

Several molecular biomarkers have been identified to guide induction treatment selection for localized pancreatic ductal adenocarcinoma (PDAC). SMAD4 alterations and low GATA6 expression/modified "Moffitt" basal-like phenotype have each been associated with inferior survival uniquely for patients receiving 5-FU-based therapies. SMAD4 may directly regulate the expression of GATA6 in PDAC, pointing to a common predictive biomarker. To evaluate the relationship between SMAD4 mutations and GATA6 expression in human PDAC tumors, patients with paired SMAD4 mutation and GATA6 mRNA expression data in the TCGA and CPTAC were identified. In 321 patients (TCGA: n = 180; CPTAC: n = 141), the rate of SMAD4 alterations was 26.8%. The rate of SMAD4 alteration did not vary per tertile of normalized GATA6 expression (TCGA: p = 0.928; CPTAC: p = 0.828). In the TCGA, SMAD4 alterations and the basal-like phenotype were each associated with worse survival (log rank p = 0.077 and p = 0.080, respectively), but their combined presence did not identify a subset with uniquely inferior survival (p = 0.943). In the CPTAC, the basal-like phenotype was associated with significantly worse survival (p < 0.001), but the prognostic value was not influenced by the combined presence of SMAD4 alterations (p = 0.960). SMAD4 alterations were not associated with poor clinico-pathological features such as poor tumor grade, advanced tumor stage, positive lymphovascular invasion (LVI), or positive perineural invasion (PNI), compared with SMAD4-wildtype. Given that SMAD4 mutations were not associated with GATA6 expression or Moffitt subtype in two independent molecularly characterized PDAC cohorts, distinct biomarker-defined clinical trials are necessary.

Segmental Versus Diffuse Main Duct Intraductal Papillary Mucinous Neoplasm: Examination of Main Pancreatic Duct Morphology and Implications for Malignancy Risk and Extent of Surgical Resection

OBJECTIVE

To determine whether the morphologic features of the main pancreatic duct (MPD) of main-duct-involved-intraductal papillary mucinous neoplasm (IPMN) (ie, main duct or mixed main duct/side branch) have implications for the risk of malignancy and extent of resection.

BACKGROUND

International consensus guidelines acknowledge the presence of various MPD morphologies (ie, diffuse vs segmental main-duct-involved-IPMN) without a precise definition of each entity and with limited data to guide treatment strategy.

METHODS

All consecutive main-duct-involved-IPMN patients (2005-2019) with a MPD diameter ≥5 mm by cross-sectional imaging were reviewed from a prospective institutional database. Morphologic features of the MPD were correlated with the identification of high-grade dysplasia or pancreatic ductal adenocarcinoma (HGD/PDAC) by logistic regression modeling. In patients who underwent partial pancreatectomy, preoperative MPD morphologic features were correlated with the future development of HGD/PDAC in the pancreatic remnant by Cox hazards modeling.

RESULTS

In a cohort of 214 main-duct-involved-IPMN patients, the overall rate of HGD/PDAC was 54.2%. MPD morphologic characteristics associated with HGD/PDAC included: maximal MPD diameter (5-10 mm: 29.8%; 10-14 mm: 59.0%; 15-19 mm: 78.6%; ≥20 mm: 95.8%; P <0.001), segmental extent of maximal dilation (<25%: 28.2%; 25%-49%: 54.9%; 50%-74%: 63.1%; ≥75%: 67.9%; P =0.002), and nonsegmental MPD diameter (<5 mm: 21.5% vs ≥5 mm: 78.5%, P <0.001). Diffuse MPD dilation involving ≥90% extent was rare (5.6%). After a median follow-up of 50 months, 7 (7.2%) patients who underwent partial pancreatectomy for IPMN without associated PDAC developed HGD/PDAC in the pancreatic remnant. Maximal MPD diameter, segmental extent of maximal dilation, or nonsegmental MPD diameter were not associated with the development of HGD/PDAC in the pancreatic remnant. However, a mural nodule on preoperative imaging was associated with the development of HGD/PDAC in the pancreatic remnant.

CONCLUSIONS

"Diffuse" involvement with homogenous dilation of the MPD was rare. For the majority of patients with segmental main-duct-involved-IPMN, the MPD morphology conferred malignancy risk. Duct morphology was not predictive for the development of HGD or invasive disease in the pancreatic remnant, implying the safety of limited pancreatic resection for initial surgical management.

Registration-based biomarkers for neoadjuvant treatment response of pancreatic cancer via longitudinal image registration

Purpose

Pancreatic ductal adenocarcinoma (PDAC) frequently presents as hypo- or iso-dense masses with poor contrast delineation from surrounding parenchyma, which decreases reproducibility of manual dimensional measurements obtained during conventional radiographic assessment of treatment response. Longitudinal registration between pre- and post-treatment images may produce imaging biomarkers that more reliably quantify treatment response across serial imaging.

Approach

Thirty patients who prospectively underwent a neoadjuvant chemotherapy regimen as part of a clinical trial were retrospectively analyzed in this study. Two image registration methods were applied to quantitatively assess longitudinal changes in tumor volume and tumor burden across the neoadjuvant treatment interval. Longitudinal registration errors of the pancreas were characterized, and registration-based treatment response measures were correlated to overall survival (OS) and recurrence-free survival (RFS) outcomes over 5-year follow-up. Corresponding biomarker assessments via manual tumor segmentation, the standardized response evaluation criteria in solid tumors (RECIST), and pathological examination of post-resection tissue samples were analyzed as clinical comparators.

Results

Average target registration errors were 2.56 ± 2.45    mm for a biomechanical image registration algorithm and 4.15 ± 3.63    mm for a diffeomorphic intensity-based algorithm, corresponding to 1-2 times voxel resolution. Cox proportional hazards analysis showed that registration-derived changes in tumor burden were significant predictors of OS and RFS, while none of the alternative comparators, including manual tumor segmentation, RECIST, or pathological variables were associated with consequential hazard ratios. Additional ROC analysis at 1-, 2-, 3-, and 5-year follow-up revealed that registration-derived changes in tumor burden between pre- and post-treatment imaging were better long-term predictors for OS and RFS than the clinical comparators.

Conclusions

Volumetric changes measured by longitudinal deformable image registration may yield imaging biomarkers to discriminate neoadjuvant treatment response in ill-defined tumors characteristic of PDAC. Registration-based biomarkers may help to overcome visual limits of radiographic evaluation to improve clinical outcome prediction and inform treatment selection.

Genomic Biomarkers Associated with Response to Induction Chemotherapy in Patients with Localized Pancreatic Ductal Adenocarcinoma

PURPOSE

There is increasing use of neoadjuvant chemotherapy in the management of localized pancreatic ductal adenocarcinoma (PDAC), yet there are few validated biomarkers to guide therapy selection. We aimed to determine whether somatic genomic biomarkers predict response to induction FOLFIRINOX or gemcitabine/nab-paclitaxel.

EXPERIMENTAL DESIGN

This single-institution cohort study included consecutive patients (N = 322) with localized PDAC (2011-2020) who received at least one cycle of FOLFIRINOX (N = 271) or gemcitabine/nab-paclitaxel (N = 51) as initial treatment. We assessed somatic alterations in four driver genes (KRAS, TP53, CDKN2A, and SMAD4) by targeted next-generation sequencing, and determined associations between these alterations and (1) rate of metastatic progression during induction chemotherapy, (2) surgical resection, and (3) complete/major pathologic response.

RESULTS

The alteration rates in driver genes KRAS, TP53, CDKN2A, and SMAD4 were 87.0%, 65.5%, 26.7%, and 19.9%, respectively. For patients receiving first-line FOLFIRINOX, SMAD4 alterations were uniquely associated with metastatic progression (30.0% vs. 14.5%; P = 0.009) and decreased rate of surgical resection (37.1% vs. 66.7%; P < 0.001). For patients receiving induction gemcitabine/nab-paclitaxel, alterations in SMAD4 were not associated with metastatic progression (14.3% vs. 16.2%; P = 0.866) nor decreased rate of surgical resection (33.3% vs. 41.9%; P = 0.605). Major pathologic response was rare (6.3%) and not associated with type of chemotherapy regimen.

CONCLUSIONS

SMAD4 alterations were associated with more frequent development of metastasis and lower probability of reaching surgical resection during neoadjuvant FOLFIRINOX but not gemcitabine/nab-paclitaxel. Confirmation in a larger, diverse patient cohort will be important before prospective evaluation of SMAD4 as a genomic biomarker to guide treatment selection.

Recurrence-free survival versus overall survival as a primary endpoint for studies of resected colorectal liver metastasis: a retrospective study and meta-analysis

BACKGROUND

Recurrence-free survival has been used as a surrogate endpoint for overall survival in trials involving patients with resected colorectal liver metastases. We aimed to assess the correlation between recurrence-free survival and overall survival after resection of colorectal liver metastases to determine the adequacy of this surrogate endpoint.

METHODS

In this retrospective study and meta-analysis, we compiled an institutional cohort of consecutive patients who had complete resection of colorectal liver metastases from the Memorial Sloan Kettering Cancer Center (New York, NY, USA) prospective database. Patients were eligible for inclusion if they were aged 18 years or older, and underwent hepatectomy, with or without operative ablation, between Jan 1, 1991, and April 30, 2019. We estimated overall survival and recurrence-free survival probabilities at various timepoints using the Kaplan-Meier method, and we assessed pairwise associations between these endpoints using Spearman's rank correlation. We also did a meta-analysis of adjuvant phase 3 clinical trials for colorectal liver metastases to assess the correlation between hazard ratios (HRs) for recurrence-free survival and overall survival. We searched MEDLINE for articles of phase 3 randomised controlled trials analysing adjuvant treatment strategies for resected colorectal metastases from database inception to Jan 1, 2022. The titles and abstracts of identified studies were screened before full-text screening and summary data were either recalculated or extracted manually from the published Kaplan-Meier curves (depending on data availability).

FINDINGS

Data were available for 3299 patients in the institutional database, of whom 2983 were eligible for inclusion in our cohort. Median follow-up was 8·4 years (95% CI 7·9-9·1) , during which time there were 1995 (67%) disease recurrences and 1684 (56%) deaths. Median recurrence-free survival was 1·3 years (95% CI 1·3-1·4) and median overall survival was 5·2 years (95% CI 5·0-5·5). 1428 (85%) of 1684 deaths were preceded by recurrence, and median time from recurrence to death was 2·0 years (IQR 1·0-3·4). Pairwise correlations between recurrence-free survival and overall survival were low to moderate, with a correlation estimate ranging from 0·30 (SD 0·17) to 0·56 (0·13). In the meta-analysis of adjuvant clinical trials, the Spearman's correlation coefficient between recurrence-free survival HR and overall survival HR was r=0·20 (p=0·71).

INTERPRETATION

We found a minimal correlation between recurrence-free survival and overall survival after resection of colorectal liver metastases. Recurrence-free survival is an inadequate surrogate endpoint for overall survival in this disease setting.

FUNDING

US National Cancer Institute.

Alterations in Somatic Driver Genes Are Associated with Response to Neoadjuvant FOLFIRINOX in Patients with Localized Pancreatic Ductal Adenocarcinoma

BACKGROUND

There is increased use of neoadjuvant fluorouracil, leucovorin, irinotecan, and oxaliplatin (FOLFIRINOX) in the management of localized pancreatic ductal adenocarcinoma (PDAC), yet there are few validated biomarkers of treatment response.

STUDY DESIGN

Consecutive patients (n = 196) with resectable, borderline resectable or locally advanced PDAC (2012-2019) receiving FOLFIRINOX as initial treatment and with targeted sequencing of a pretreatment biopsy were identified in a prospective institutional database. Genomic alterations were determined in the 4 driver mutations (KRAS, TP53, CDKN2A, SMAD4), and associations between genomic alterations and clinical outcomes were assessed.

RESULTS

Alterations in KRAS (n = 172, 87.8%) and TP53 (n = 131, 66.8%) were common; alterations in CDKN2A (n = 49, 25.0%) and SMAD4 (n = 36, 18.4%) were less frequently observed. A total of 105 patients (53.6%) were able to undergo resection, of whom 8 (7.6%) had a complete/near-complete pathologic response. There were no somatic alterations associated with major pathologic response. Alterations in SMAD4 were associated with a lower rate of surgical resection (27.8% vs 59.4%, p < 0.001); this was additionally observed in a multivariable regression model accounting for resectability status (OR 0.35, 95% confidence interval [CI] 0.15-0.85). Thirty-three patients (16.8%) developed metastatic disease while on neoadjuvant therapy. SMAD4 alterations were associated with a significant risk of metastatic progression on therapy when controlling for resectability status (OR 3.31, 95% CI 1.44-7.60).

CONCLUSIONS

SMAD4 alterations are associated with more frequent development of metastasis during neoadjuvant FOLFIRINOX and lower probability of reaching surgical resection. Evaluation of alternative chemotherapy regimens in patients with SMAD4 alterations will be important to distinguish whether this represents a prognostic or predictive biomarker.

Stromal changes in the aged lung induce an emergence from melanoma dormancy

Disseminated cancer cells from primary tumours can seed in distal tissues, but may take several years to form overt metastases, a phenomenon that is termed tumour dormancy. Despite its importance in metastasis and residual disease, few studies have been able to successfully characterize dormancy within melanoma. Here we show that the aged lung microenvironment facilitates a permissive niche for efficient outgrowth of dormant disseminated cancer cells-in contrast to the aged skin, in which age-related changes suppress melanoma growth but drive dissemination. These microenvironmental complexities can be explained by the phenotype switching model, which argues that melanoma cells switch between a proliferative cell state and a slower-cycling, invasive state1-3. It was previously shown that dermal fibroblasts promote phenotype switching in melanoma during ageing4-8. We now identify WNT5A as an activator of dormancy in melanoma disseminated cancer cells within the lung, which initially enables the efficient dissemination and seeding of melanoma cells in metastatic niches. Age-induced reprogramming of lung fibroblasts increases their secretion of the soluble WNT antagonist sFRP1, which inhibits WNT5A in melanoma cells and thereby enables efficient metastatic outgrowth. We also identify the tyrosine kinase receptors AXL and MER as promoting a dormancy-to-reactivation axis within melanoma cells. Overall, we find that age-induced changes in distal metastatic microenvironments promote the efficient reactivation of dormant melanoma cells in the lung.

Genomic Stratification of Resectable Colorectal Liver Metastasis Patients and Implications for Adjuvant Therapy and Survival

OBJECTIVE

To determine whether genomic risk groups identified by somatic mutation testing of colorectal liver metastasis (CRLM) can be used for "molecularly-guided" selection for adjuvant systemic chemotherapy and hepatic artery infusion of FUDR (SYS+HAI-FUDR).

BACKGROUND

Several genomic biomarkers have been associated with clinical phenotype and survival for patients with resectable CRLM. It is unknown whether prognostication afforded by genomic stratification translates into enhanced patient selection for adjuvant hepatic artery infusion therapy.

METHODS

Consecutive patients with resected CRLM and available mutational characterization via Memorial Sloan Kettering-Integrated Mutation Profiling of Actionable Cancer Targets were reviewed from a prospective institutional database. Patients were stratified into three genomic risk groups based on previously defined alterations in SMAD4, EGFR and the RAS/RAF pathway. The association between SYS+HAI-FUDR and overall survival, relative to adjuvant chemotherapy alone (SYS), was evaluated in each genomic risk group by Cox proportional hazard regression and propensity score matched analyses.

RESULTS

A total of 334 patients (SYS+HAI-FUDR 204; SYS 130) were identified; the rates of RAS/RAF alterations and SMAD4 inactivation were 47.4% and 11.7%, respectively. After a median follow-up of 58 months, adjuvant SYS+HAI-FUDR was independently associated with a reduced risk of death (HR 0.50, 95%CI 0.26-0.98, P = 0.045) in the low-risk genomic group, but not in the moderate-risk (HR 1.07, 95%CI 0.5-2.07, P = 0.749) or high-risk (HR 1.62, 95%CI 0.29-9.12, P = 0.537) cohorts. Following propensity score matching, adjuvant SYS+HAI-FUDR remained associated with significant improvements in long-term survival selectively in the low-risk genomic cohort (5-year actuarial survival: 89% vs. 68%, P = 0.019).

CONCLUSIONS

Genomic alterations in RAS/RAF, SMAD4, and EGFR may be useful to guide treatment selection in resectable CRLM patients and warrant external validation and integration in future clinical trial design.

The Fistula Risk Score Catalog: Toward Precision Medicine for Pancreatic Fistula After Pancreatoduodenectomy

OBJECTIVE

This study aims to present a full spectrum of individual patient presentations of pancreatic fistula risk, and to define the utility of mitigation strategies amongst some of the most prevalent, and vulnerable scenarios surgeons encounter.

BACKGROUND

The FRS has been utilized to identify technical strategies associated with reduced CR-POPF incidence across various risk strata. However, risk-stratification using the FRS has never been investigated with greater granularity. By deriving all possible combinations of FRS elements, individualized risk assessment could be utilized for precision medicine purposes.

METHODS

FRS profiles and outcomes of 5533 PDs were accrued from 17 international institutions (2003-2019). The FRS was used to derive 80 unique combinations of patient "scenarios." Risk-matched analyses were conducted using a Bonferroni adjustment to identify scenarios with increased vulnerability for CR-POPF occurrence. Subsequently, these scenarios were analyzed using multivariable regression to explore optimal mitigation approaches.

RESULTS

The overall CR-POPF rate was 13.6%. All 80 possible scenarios were encountered, with the most frequent being scenario #1 (8.1%) - the only negligible-risk scenario (CR-POPF rate = 0.7%). The moderate-risk zone had the most scenarios (50), patients (N = 3246), CR-POPFs (65.2%), and greatest non-zero discrepancy in CR-POPF rates between scenarios (18-fold). In the risk-matched analysis, 2 scenarios (#59 and 60) displayed increased vulnerability for CR-POPF relative to the moderate-risk zone (both P < 0.001). Multivariable analysis revealed factors associated with CR-POPF in these scenarios: pancreaticogastrostomy reconstruction [odds ratio (OR) 4.67], omission of drain placement (OR 5.51), and prophylactic octreotide (OR 3.09). When comparing the utilization of best practice strategies to patients who did not have these conjointly utilized, there was a significant decrease in CR-POPF (10.7% vs 35.5%, P < 0.001; OR 0.20, 95% confidence interval 0.12-0.33).

CONCLUSION

Through this data, a comprehensive fistula risk catalog has been created and the most clinically-impactful scenarios have been discerned. Focusing on individual scenarios provides a practical way to approach precision medicine, allowing for more directed and efficient management of CR-POPF.

Registry-based randomized clinical trials in surgery: Working with ACS-NSQIP and the AHPBA to conduct pragmatic trials

Randomized controlled trials (RCTs) represent the gold standard for evidence in clinical medicine because of their ability to account for the effects of unmeasured confounders and selection bias by indication. However, their complexity and immense costs limit their application, and thus the availability of high-quality data to guide clinical care. Registry-based RCTs are a type of pragmatic trial that leverages existing registries as a platform for data collection, providing a low-cost alternative for randomized studies. Herein, we describe the tenets of registry RCTs and the development of the first AHPBA/ACS-NSQIP-based registry trial.

Genome-Derived Classification Signature for Ampullary Adenocarcinoma to Improve Clinical Cancer Care

PURPOSE

The clinical behavior of ampullary adenocarcinoma varies widely. Targeted tumor sequencing may better define biologically distinct subtypes to improve diagnosis and management.

EXPERIMENTAL DESIGN

The hidden-genome algorithm, a multilevel meta-feature regression model, was trained on a prospectively sequenced cohort of 3,411 patients (1,001 pancreatic adenocarcinoma, 165 distal bile-duct adenocarcinoma, 2,245 colorectal adenocarcinoma) and subsequently applied to targeted panel DNA-sequencing data from ampullary adenocarcinomas. Genomic classification (i.e., colorectal vs. pancreatic) was correlated with standard histologic classification [i.e., intestinal (INT) vs. pancreatobiliary (PB)] and clinical outcome.

RESULTS

Colorectal genomic subtype prediction was primarily influenced by mutations in APC and PIK3CA, tumor mutational burden, and DNA mismatch repair (MMR)-deficiency signature. Pancreatic genomic-subtype prediction was dictated by KRAS gene alterations, particularly KRAS G12D, KRAS G12R, and KRAS G12V. Distal bile-duct adenocarcinoma genomic subtype was most influenced by copy-number gains in the MDM2 gene. Despite high (73%) concordance between immunomorphologic subtype and genomic category, there was significant genomic heterogeneity within both histologic subtypes. Genomic scores with higher colorectal probability were associated with greater survival compared with those with a higher pancreatic probability.

CONCLUSIONS

The genomic classifier provides insight into the heterogeneity of ampullary adenocarcinoma and improves stratification, which is dictated by the proportion of colorectal and pancreatic genomic alterations. This approach is reproducible with available molecular testing and obviates subjective histologic interpretation.

Myeloid-Derived Suppressor Cells Are a Major Source of Wnt5A in the Melanoma Microenvironment and Depend on Wnt5A for Full Suppressive Activity

Metastatic dissemination remains a significant barrier to successful therapy for melanoma. Wnt5A is a potent driver of invasion in melanoma and is believed to be secreted from the tumor microenvironment (TME). Our data suggest that myeloid-derived suppressor cells (MDSC) in the TME are a major source of Wnt5A and are reliant upon Wnt5A for multiple actions. Knockdown of Wnt5A specifically in the myeloid cells demonstrated a clear decrease in Wnt5A expression within the TME in vivo as well as a decrease in intratumoral MDSC and regulatory T cell (Treg). Wnt5A knockdown also decreased the immunosuppressive nature of MDSC and decreased expression of TGFβ1 and arginase 1. In the presence of Wnt5A-depleted MDSC, tumor-infiltrating lymphocytes expressed decreased PD-1 and LAG3, suggesting a less exhausted phenotype. Myeloid-specific Wnt5A knockdown also led to decreased lung metastasis. Tumor-infiltrating MDSC from control animals showed a strong positive correlation with Treg, which was completely ablated in animals with Wnt5A-negative MDSC. Overall, our data suggest that while MDSC contribute to an immunosuppressive and less immunogenic environment, they exhibit an additional function as the major source of Wnt5A in the TME. SIGNIFICANCE: These findings demonstrate that myeloid cells provide a major source of Wnt5A to facilitate metastatic potential in melanoma cells and rely on Wnt5A for their immunosuppressive function.

sFRP2 Supersedes VEGF as an Age-related Driver of Angiogenesis in Melanoma, Affecting Response to Anti-VEGF Therapy in Older Patients

PURPOSE

Angiogenesis is thought to be critical for tumor metastasis. However, inhibiting angiogenesis using antibodies such as bevacizumab (Avastin), has had little impact on melanoma patient survival. We have demonstrated that both angiogenesis and metastasis are increased in older individuals, and therefore sought to investigate whether there was an age-related difference in response to bevacizumab, and if so, what the underlying mechanism could be.

EXPERIMENTAL DESIGN

We analyzed data from the AVAST-M trial of 1,343 patients with melanoma treated with bevacizumab to determine whether there is an age-dependent response to bevacizumab. We also examined the age-dependent expression of VEGF and its cognate receptors in patients with melanoma, while using syngeneic melanoma animal models to target VEGF in young versus old mice. We also examined the age-related proangiogenic factor secreted frizzled-related protein 2 (sFRP2) and whether it could modulate response to anti-VEGF therapy.

RESULTS

We show that older patients respond poorly to bevacizumab, whereas younger patients show improvement in both disease-free survival and overall survival. We find that targeting VEGF does not ablate angiogenesis in an aged mouse model, while sFRP2 promotes angiogenesis in vitro and in young mice. Targeting sFRP2 in aged mice successfully ablates angiogenesis, while the effects of targeting VEGF in young mice can be overcome by increasing sFRP2.

CONCLUSIONS

VEGF is decreased during aging, thereby reducing response to bevacizumab. Despite the decrease in VEGF, angiogenesis is increased because of an increase in sFRP2 in the aged tumor microenvironment. These results stress the importance of considering age as a factor for designing targeted therapies.

Surgical Management of Sarcoma Metastatic to Liver

Sarcomas are rare mesenchymal tumors with a propensity for hematogenous metastasis. Gastrointestinal stromal tumor (GIST) is the most common histologic subtype and the most common source of hepatic metastases. In the case of metastatic GIST, neoadjuvant imatinib can be used as a selection tool for the judicious application of surgery, where treatment-responsive patients who undergo resection to prevent the development of treatment-resistant clones have associated 10-year actuarial survival of 40%. Further advances for many of the non-GIST sarcoma subtypes will depend on the development of improved systemic therapies and evaluation of their activity in subtype or molecularly defined trials.

Defining postoperative weight change after pancreatectomy: Factors associated with distinct and dynamic weight trajectories

BACKGROUND

Weight change offers the simplest indication of a patient's recovery after an operation. There have been no studies that have thoroughly investigated postoperative weight dynamics after pancreatectomy. The aim of this study was to define postoperative weight change after a pancreatectomy and determine factors associated with optimal and poor weight trajectories.

METHODS

From 2004 to 2019, 1,090 proximal (65%) and distal (35%) pancreatectomies were performed in patients with adequate data in the medical records. Patient weights were acquired preoperatively and at postoperative months 1, 3, and 12. Optimal (top quartile, weight restoration) and poor (bottom quartile, persistent weight loss) postoperative weight cohorts were identified at 1 year postoperatively.

RESULTS

The median percentage weight change 1 year postpancreatectomy was -6.6% (interquartile range: -1.4% to -12.5%), -7.8% for proximal pancreatectomy, and -4.2% for distal pancreatectomy. For most patients (interquartile range cohort), the median percentage weight change at 1, 3, and 12 months was -6.2%, -7.2%, and -6.6%. The independent factors associated with weight restoration were age <65, nonobesity (body mass index <30kg/m²), receiving total parenteral nutrition/total enteral nutrition preoperatively, experiencing preoperative weight loss >10%, distal pancreatectomy, not undergoing vascular resection, and no readmission within 30 days. Conversely, persistent weight loss was associated with American Society of Anesthesiologists classes III to IV, obesity, malignancy, proximal pancreatectomy, blood loss ≥350mL, and experiencing readmission within 30 days. Focusing on pancreatic ductal adenocarcinoma (n = 372) patients, the factors associated with persistent weight loss were obesity, proximal pancreatectomy, and experiencing recurrence within 1 year; however, weight cohorts were not associated with overall survival for pancreatic ductal adenocarcinoma patients.

CONCLUSION

These data define weight kinetics after pancreatectomy. Ultimately, postoperative weight trajectories appear to be largely predetermined but may be mitigated by limiting readmissions and complications. Clinicians should use these data to identify patients who continue to lose weight between the first and third month postoperatively with a high suspicion for the requirement of nutritional monitoring or other interventions.

Role of Adjuvant Multimodality Therapy After Curative-Intent Resection of Ampullary Carcinoma

Importance

Ampullary adenocarcinoma is a rare malignant neoplasm that arises within the duodenal ampullary complex. The role of adjuvant therapy (AT) in the treatment of ampullary adenocarcinoma has not been clearly defined.

Objective

To determine if long-term survival after curative-intent resection of ampullary adenocarcinoma may be improved by selection of patients for AT directed by histologic subtype.

Design, Setting, and Participants

This multinational, retrospective cohort study was conducted at 12 institutions from April 1, 2000, to July 31, 2017, among 357 patients with resected, nonmetastatic ampullary adenocarcinoma receiving surgery alone or AT. Cox proportional hazards regression was used to identify covariates associated with overall survival. The surgery alone and AT cohorts were matched 1:1 by propensity scores based on the likelihood of receiving AT or by survival hazard from Cox modeling. Overall survival was compared with Kaplan-Meier estimates.

Exposures

Adjuvant chemotherapy (fluorouracil- or gemcitabine-based) with or without radiotherapy.

Main Outcomes and Measures

Overall survival.

Results

A total of 357 patients (156 women and 201 men; median age, 65.8 years [interquartile range, 58-74 years]) underwent curative-intent resection of ampullary adenocarcinoma. Patients with intestinal subtype had a longer median overall survival compared with those with pancreatobiliary subtype (77 vs 54 months; P = .05). Histologic subtype was not associated with AT administration (intestinal, 52.9% [101 of 191]; and pancreatobiliary, 59.5% [78 of 131]; P = .24). Patients with pancreatobiliary histologic subtype most commonly received gemcitabine-based regimens (71.0% [22 of 31]) or combinations of gemcitabine and fluorouracil (12.9% [4 of 31]), whereas treatment of those with intestinal histologic subtype was more varied (fluorouracil, 50.0% [17 of 34]; gemcitabine, 44.1% [15 of 34]; P = .01). In the propensity score-matched cohort, AT was not associated with a survival benefit for either histologic subtype (intestinal: hazard ratio, 1.21; 95% CI, 0.67-2.16; P = .53; pancreatobiliary: hazard ratio, 1.35; 95% CI, 0.66-2.76; P = .41).

Conclusions and Relevance

Adjuvant therapy was more frequently used in patients with poor prognostic factors but was not associated with demonstrable improvements in survival, regardless of tumor histologic subtype. The value of a multimodality regimen remains poorly defined.

Changes in Aged Fibroblast Lipid Metabolism Induce Age-Dependent Melanoma Cell Resistance to Targeted Therapy via the Fatty Acid Transporter FATP2

Older patients with melanoma (>50 years old) have poorer prognoses and response rates to targeted therapy compared with young patients (<50 years old), which can be driven, in part, by the aged microenvironment. Here, we show that aged dermal fibroblasts increase the secretion of neutral lipids, especially ceramides. When melanoma cells are exposed to the aged fibroblast lipid secretome, or cocultured with aged fibroblasts, they increase the uptake of lipids via the fatty acid transporter FATP2, which is upregulated in melanoma cells in the aged microenvironment and known to play roles in lipid synthesis and accumulation. We show that blocking FATP2 in melanoma cells in an aged microenvironment inhibits their accumulation of lipids and disrupts their mitochondrial metabolism. Inhibiting FATP2 overcomes age-related resistance to BRAF/MEK inhibition in animal models, ablates tumor relapse, and significantly extends survival time in older animals. SIGNIFICANCE: These data show that melanoma cells take up lipids from aged fibroblasts, via FATP2, and use them to resist targeted therapy. The response to targeted therapy is altered in aged individuals because of the influences of the aged microenvironment, and these data suggest FATP2 as a target to overcome resistance.See related commentary by Montal and White, p. 1255.This article is highlighted in the In This Issue feature, p. 1241.

Paradoxical Role for Wild-Type p53 in Driving Therapy Resistance in Melanoma

Metastatic melanoma is an aggressive disease, despite recent improvements in therapy. Eradicating all melanoma cells even in drug-sensitive tumors is unsuccessful in patients because a subset of cells can transition to a slow-cycling state, rendering them resistant to most targeted therapy. It is still unclear what pathways define these subpopulations and promote this resistant phenotype. In the current study, we show that Wnt5A, a non-canonical Wnt ligand that drives a metastatic, therapy-resistant phenotype, stabilizes the half-life of p53 and uses p53 to initiate a slow-cycling state following stress (DNA damage, targeted therapy, and aging). Inhibiting p53 blocks the slow-cycling phenotype and sensitizes melanoma cells to BRAF/MEK inhibition. In vivo, this can be accomplished with a single dose of p53 inhibitor at the commencement of BRAF/MEK inhibitor therapy. These data suggest that taking the paradoxical approach of inhibiting rather than activating wild-type p53 may sensitize previously resistant metastatic melanoma cells to therapy.

Defining the Safety Profile for Performing Pancreatoduodenectomy in the Setting of Hyperbilirubinemia

BACKGROUND

Hyperbilirubinemia is commonly observed in patients requiring pancreatoduodenectomy (PD). Thus far, literature regarding the danger of operating in the setting of hyperbilirubinemia is equivocal. What remains undefined is at what specific level of bilirubin there is an adverse safety profile for undergoing PD. The aim of this study is to identify the optimal safety profile of patients with hyperbilirubinemia undergoing PD.

PATIENTS AND METHODS

The present work analyzed 803 PDs from 2004 to 2018. A generalized additive model was used to determine cutoff values of total serum bilirubin (TB) that were associated with increases in adverse outcomes, including 90-day mortality. Subgroup comparisons and biliary stent-specific analyses were performed for patients with TB below and above the cutoff.

RESULTS

TB of 13 mg/dL was associated with an increase in 90-day mortality (P = 0.043) and was the dominant risk factor on multivariate logistic regression [odds ratio (OR) 8.193, P = 0.001]. Increased TB levels were also associated with reoperations, number of complications per patient, and length of stay. Patients with TB greater than or equal to 13 mg/dL (TB ≥ 13) who received successful biliary decompression through stenting had less combined death and serious morbidity (P = 0.048).

CONCLUSIONS

Preoperative TB ≥ 13 mg/dL was associated with increased 90-day mortality after PD. Reducing a TB ≥ 13 is generally recommended before proceeding to surgery.

Impact of obesity on breast cancer recurrence and minimal residual disease

BACKGROUND

Obesity is associated with an increased risk of breast cancer recurrence and cancer death. Recurrent cancers arise from the pool of residual tumor cells, or minimal residual disease (MRD), that survives primary treatment and persists in the host. Whether the association of obesity with recurrence risk is causal is unknown, and the impact of obesity on MRD and breast cancer recurrence has not been reported in humans or in animal models.

METHODS

Doxycycline-inducible primary mammary tumors were generated in intact MMTV-rtTA;TetO-HER2/neu (MTB/TAN) mice or orthotopic recipients fed a high-fat diet (HFD; 60% kcal from fat) or a control low-fat diet (LFD; 10% kcal from fat). Following oncogene downregulation and tumor regression, mice were followed for clinical recurrence. Body weight was measured twice weekly and used to segregate HFD mice into obese (i.e., responders) and lean (i.e., nonresponders) study arms, and obesity was correlated with body fat percentage, glucose tolerance (measured using intraperitoneal glucose tolerance tests), serum biomarkers (measured by enzyme-linked immunosorbent assay), and tissue transcriptomics (assessed by RNA sequencing). MRD was quantified by droplet digital PCR.

RESULTS

HFD-Obese mice weighed significantly more than HFD-Lean and LFD control mice (p < 0.001) and had increased body fat percentage (p < 0.001). Obese mice exhibited fasting hyperglycemia, hyperinsulinemia, and impaired glucose tolerance, as well as decreased serum levels of adiponectin and increased levels of leptin, resistin, and insulin-like growth factor 1. Tumor recurrence was accelerated in HFD-Obese mice compared with HFD-Lean and LFD control mice (median relapse-free survival 53.0 days vs. 87.0 days vs. 80.0 days, log-rank p < 0.001; HFD-Obese compared with HFD-Lean HR 2.52, 95% CI 1.52-4.16; HFD-Obese compared with LFD HR 2.27, 95% CI 1.42-3.63). HFD-Obese mice harbored a significantly greater number of residual tumor cells than HFD-Lean and LFD mice (12,550 ± 991 vs. 7339 ± 2182 vs. 4793 ± 1618 cells, p < 0.001).

CONCLUSION

These studies provide a genetically engineered mouse model for study of the association of diet-induced obesity with breast cancer recurrence. They demonstrate that this model recapitulates physiological changes characteristic of obese patients, establish that the association between obesity and recurrence risk is causal in nature, and suggest that obesity is associated with the increased survival and persistence of residual tumor cells.

Age Correlates with Response to Anti-PD1, Reflecting Age-Related Differences in Intratumoral Effector and Regulatory T-Cell Populations

Purpose: We have shown that the aged microenvironment increases melanoma metastasis, and decreases response to targeted therapy, and here we queried response to anti-PD1.Experimental Design: We analyzed the relationship between age, response to anti-PD1, and prior therapy in 538 patients. We used mouse models of melanoma, to analyze the intratumoral immune microenvironment in young versus aged mice and confirmed our findings in human melanoma biopsies.Results: Patients over the age of 60 responded more efficiently to anti-PD-1, and likelihood of response to anti-PD-1 increased with age, even when we controlled for prior MAPKi therapy. Placing genetically identical tumors in aged mice (52 weeks) significantly increased their response to anti-PD1 as compared with the same tumors in young mice (8 weeks). These data suggest that this increased response in aged patients occurs even in the absence of a more complex mutational landscape. Next, we found that young mice had a significantly higher population of regulatory T cells (Tregs), skewing the CD8+:Treg ratio. FOXP3 staining of human melanoma biopsies revealed similar increases in Tregs in young patients. Depletion of Tregs using anti-CD25 increased the response to anti-PD1 in young mice.Conclusions: While there are obvious limitations to our study, including our inability to conduct a meta-analysis due to a lack of available data, and our inability to control for mutational burden, there is a remarkable consistency in these data from over 500 patients across 8 different institutes worldwide. These results stress the importance of considering age as a factor for immunotherapy response. Clin Cancer Res; 24(21); 5347-56. ©2018 AACR See related commentary by Pawelec, p. 5193.

Age-Related Changes in HAPLN1 Increase Lymphatic Permeability and Affect Routes of Melanoma Metastasis

Older patients with melanoma have lower rates of sentinel lymph node (LN) metastases yet paradoxically have inferior survival. Patient age correlated with an inability to retain Technetium radiotracer during sentinel LN biopsy in more than 1,000 patients, and high Technetium counts correlated to better survival. We hypothesized that loss of integrity in the lymphatic vasculature due to extracellular matrix (ECM) degradation might play a role. We have implicated HAPLN1 in age-dependent ECM degradation in the dermis. Here, we queried whether HAPLN1 could be altered in the lymphatic ECM. Lymphatic HAPLN1 expression was prognostic of long-term patient survival. Adding recombinant HAPLN1 to aged fibroblast ECMs in vitro reduced endothelial permeability via modulation of VE-cadherin junctions, whereas endothelial permeability was increased following HAPLN1 knockdown in young fibroblasts. In vivo, reconstitution of HAPLN1 in aged mice increased the number of LN metastases, but reduced visceral metastases. These data suggest that age-related changes in ECM can contribute to impaired lymphatics. SIGNIFICANCE: Our studies reveal that changes in the stroma during aging may influence the way tumor cells traffic through the lymphatic vasculature. Aging may dictate the route of metastatic dissemination of tumor cells, and understanding these changes may help to reveal targetable moieties in the aging tumor microenvironment.See related commentary by Marie and Merlino, p. 19.This article is highlighted in the In This Issue feature, p. 1.

Remodeling of the Collagen Matrix in Aging Skin Promotes Melanoma Metastasis and Affects Immune Cell Motility

Physical changes in skin are among the most visible signs of aging. We found that young dermal fibroblasts secrete high levels of extracellular matrix (ECM) constituents, including proteoglycans, glycoproteins, and cartilage-linking proteins. The most abundantly secreted was HAPLN1, a hyaluronic and proteoglycan link protein. HAPLN1 was lost in aged fibroblasts, resulting in a more aligned ECM that promoted metastasis of melanoma cells. Reconstituting HAPLN1 inhibited metastasis in an aged microenvironment, in 3-D skin reconstruction models, and in vivo. Intriguingly, aged fibroblast-derived matrices had the opposite effect on the migration of T cells, inhibiting their motility. HAPLN1 treatment of aged fibroblasts restored motility of mononuclear immune cells, while impeding that of polymorphonuclear immune cells, which in turn affected regulatory T-cell recruitment. These data suggest that although age-related physical changes in the ECM can promote tumor cell motility, they may adversely affect the motility of some immune cells, resulting in an overall change in the immune microenvironment. Understanding the physical changes in aging skin may provide avenues for more effective therapy for older patients with melanoma. SIGNIFICANCE: These data shed light on the mechanochemical interactions that occur between aged skin, tumor, and immune cell populations, which may affect tumor metastasis and immune cell infiltration, with implications for the efficacy of current therapies for melanoma.See related commentary by Marie and Merlino, p. 19.This article is highlighted in the In This Issue feature, p. 1.

Abstract 993: Wnt-er is coming: WNT5A promotes a slow cycling phenotype via p53 in conditions of stress

Resistance to targeted therapy and chemotherapy increases with age. Previously, we found that aged skin fibroblasts secrete sFRP2, which decreases ß-catenin, MITF, and APE1 in melanoma cells, and promotes invasion. Loss of APE1, a key redox effector, increased DNA damage in melanoma cells and caused the cells to become resistant to targeted therapy. Here we show that the aging tumor microenvironment drives a slow cycling phenotype in melanoma cells via WNT5A and p53. We found WNT5A expression in melanoma cells correlates with p53 expression and a higher percent of slow cycling cells. Knocking down WNT5A decreases both p53 expression and the percent of slow cycling cells. When we isolated slow cycling cells by flow cytometry, we found that they have increased WNT5A, p53, and p21 expression. Analysis of patient tumors in the TCGA data base revealed that patients with higher than average p53 expression, also express WNT5A. To determine if WNT5A and p53 may be promoting the survival of metastatic melanoma in an aged microenvironment, we examined tumors from young and aged C57/BL6 mice generated using Yumm1.7 cells. We found that tumors in aged mice have a higher percentage of cells expressing p53 and increased WNT5A expression compared to tumors in young mice. Treatment of human melanoma cells with conditioned media from aged dermal fibroblasts decreases proliferation and increases the percent of slow cycling. Inhibition of p53 re-sensitizes human melanoma cells in conditioned media from aged fibroblasts to combination BRAFi/MEKi. These data suggest, it may be these slow cycling cells driven by WNT5A and p53, which are enriched in an aging microenvironment, that are driving resistance to targeted therapy in aged patients.

Citation Format: Marie R. Webster, Mitchell Fane, Amanpreet Kaur, Gretchen Alicea, Brett L. Ecker, Abibatou Ndoye, Curtis Kugel, Subhasree Basu, Alexander Valiga, Jessica L. Appleton, Maureen E. Murphy, Ashani Weeraratna. Wnt-er is coming: WNT5A promotes a slow cycling phenotype via p53 in conditions of stress [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 993.

Acid Suspends the Circadian Clock in Hypoxia through Inhibition of mTOR

Recent reports indicate that hypoxia influences the circadian clock through the transcriptional activities of hypoxia-inducible factors (HIFs) at clock genes. Unexpectedly, we uncover a profound disruption of the circadian clock and diurnal transcriptome when hypoxic cells are permitted to acidify to recapitulate the tumor microenvironment. Buffering against acidification or inhibiting lactic acid production fully rescues circadian oscillation. Acidification of several human and murine cell lines, as well as primary murine T cells, suppresses mechanistic target of rapamycin complex 1 (mTORC1) signaling, a key regulator of translation in response to metabolic status. We find that acid drives peripheral redistribution of normally perinuclear lysosomes away from perinuclear RHEB, thereby inhibiting the activity of lysosome-bound mTOR. Restoring mTORC1 signaling and the translation it governs rescues clock oscillation. Our findings thus reveal a model in which acid produced during the cellular metabolic response to hypoxia suppresses the circadian clock through diminished translation of clock constituents.

Combination of Neoadjuvant Transcatheter Arterial Chemoembolization and Orthotopic Liver Transplantation for the Treatment of Cirrhotomimetic Hepatocellular Carcinoma

PURPOSE

To examine differences in outcome and response of cirrhotomimetic (CMM) hepatocellular carcinoma (HCC) to a combination of bridging transcatheter arterial chemoembolization and orthotopic liver transplantation (OLT) compared with non-CMM HCC.

MATERIALS AND METHODS

All patients with pathologically proven CMM HCC who underwent bridging transcatheter arterial chemoembolization before OLT between 2007 and 2013 (n = 23) were retrospectively compared with a control group of patients with pathologically proven non-CMM HCC (n = 46).

RESULTS

There were 29 tumors in the CMM HCC group and 64 tumors in the non-CMM group identified and treated. Objective response rate on MR imaging at 1 and 3 months after transcatheter arterial chemoembolization for CMM HCC tumors (including patients with complete and partial response) was 93.1% and 86.4% compared with 85.2% and 93.2% for non-CMM tumors without statistically significant difference (P = .54 and P = .09, respectively). Pathologic study of liver explants showed complete tumor necrosis in 62.3% of non-CMM tumors (38/61) compared with 10.3% of CMM tumors (3/29) (P < .0001). Overall 2-year survival after transcatheter arterial chemoembolization and OLT was significantly lower for patients with CMM HCC compared with patients non-CMM HCC (65.2% vs 87%, P = .03). Patients with CMM HCC with extranodular tumor extension involving > 50% of liver parenchyma had worse survival with mean 2-year survival of 402 days ± 102 vs 656 days ± 39 for the remaining patients with CMM HCC (P = .02).

CONCLUSIONS

Despite similar early imaging response rates, CMM HCC tumors had markedly lower rates of complete pathologic necrosis on liver explants and were associated with reduced survival after OLT compared with conventional HCCs.

Identification of Patients for Adjuvant Therapy After Resection of Carcinoma of the Extrahepatic Bile Ducts: A Propensity Score-Matched Analysis

BACKGROUND

Resectability rates for extrahepatic cholangiocarcinoma have increased over time, but long-term survival after resection alone with curative intent remains poor. Recent series suggest improved survival with adjuvant therapy. Patient subsets benefiting most from adjuvant therapy have not been clearly defined.

METHODS

Patients with extrahepatic cholangiocarcinoma who underwent resection with curative intent and received adjuvant therapy (chemotherapy ± radiotherapy) or surgery alone (SA) were identified in the U.S. National Cancer Data Base (2004-2014). Cox regression identified covariates associated with overall survival (OS). Adjuvant therapy and SA cohorts were matched (1:1) by propensity scores based on the survival hazard in Cox modeling. Overall survival was compared by Kaplan-Meier estimates.

RESULTS

Of 4872 patients, adjuvant chemotherapy was used frequently for 2416 (49.6%), often in conjunction with radiotherapy (RT) (n = 1555, 64.4%). Adjuvant chemotherapy with or without RT was used increasingly for cases with higher T classification [reference: T1-2; T3: 1.36; 95% confidence interval (CI), 1.19-1.55; T4: 1.77; 95% CI 1.38-2.26], nodal positivity [odds ratio (OR), 1.26; 95% CI 1.01-1.56], lymphovascular invasion (OR 1.21; 95% CI 1.01-1.46), or margin-positive resection (OR 1.85; 95% CI 1.61-2.12), and was associated with significant improvements in OS for each high-risk subset in the propensity score-matched cohort. Adjuvant therapy was associated with improved median OS for hilar tumors (40.0 vs 30.6 months; p = 0.025) but not distal tumors (33.0 vs 30.3 months; p = 0.123). Chemoradiotherapy was associated with superior outcomes compared with chemotherapy alone in the subset of margin-positive resection [hazard ratio (HR), 0.63; 95% CI 0.42-0.94].

CONCLUSIONS

Adjuvant multimodality therapy is associated with improved survival for patients with resected extrahepatic cholangiocarcinoma and high-risk features.

Adjuvant chemotherapy in resectable synovial sarcoma

INTRODUCTION

The role of adjuvant chemotherapy (AC) for synovial sarcoma (SS) is controversial. Using a large national dataset we evaluate the impact of AC on overall survival (OS) following curative-intent resection of SS.

METHODS

Patients with stage I-III SS 2004-2012 undergoing resection were identified in the National Cancer Data Base. Clinicopathologic factors associated with OS were identified using Cox proportional-hazard modeling, adjusting for factors associated with receipt of AC.

RESULTS

Among 544 patients, 131 received AC. Median age of the cohort was 42 years; 269 were female. AC was not associated with OS in univariate analysis in the overall cohort. After stratification by stage, AC was associated with prolonged OS in univariate analysis in stage III patients only (P = 0.028), which remained significant in multivariable analysis (P = 0.033). Other factors associated with OS in stage III patients were age >55 years, (P = 0.001), positive margins (P = 0.037), biphasic histology (P = 0.013), and adjuvant radiation (P < 0.001). The association between AC and OS remained significant after adjustment for factors predictive of receipt of AC.

CONCLUSIONS

In this national cohort, AC was associated with prolonged OS for SS for stage III patients but not in lower stages. Less restricted use of this therapy may be warranted in this population.

Pancreatic fistula risk for pancreatoduodenectomy: an international survey of surgeon perception

INTRODUCTION

Clinically relevant postoperative pancreatic fistula (CR-POPF) is a morbid complication following pancreatoduodenectomy (PD). It is unclear how pancreatic surgeons perceive risk for this complication, and the implications thereof.

METHODS

A web-based survey was distributed to members of 22 international GI surgical societies. CR-POPF risk factors were categorized as follows: (i) patient factors, (ii) pancreatic gland characteristics, (iii) intraoperative variables, (iv) perioperative mitigation techniques, or (v) institutional features.

RESULTS

Surveys were completed by 897 surgeons worldwide. The most commonly cited contributors to CR-POPF risk were gland characteristics (90.7%), while patient and intraoperative factors were selected 71.2 and 69.3% of the time, respectively. Conversely, institutional features (31.7%) and perioperative mitigation techniques (21.3%) were rarely recognized. Eighty percent of surgeons use drain amylase concentration to guide drain removal decision-making; however, only 45.2% of surgeon remove drains early based upon drain amylase values. When evaluating clinical scenarios, surgeons were able to identify both negligible and high risk scenarios but struggled to differentiate between low and moderate CR-POPF risk.

CONCLUSION

This international study analyzed how surgeons discern CR-POPF risk for PD. There was considerable variability in surgeons' perceptions of risk, which may have an adverse effect on the clinical use of risk adjustment measures.

Contemporary reappraisal of the efficacy of adjuvant chemotherapy in resected retroperitoneal sarcoma: Evidence from a nationwide clinical oncology database and review of the literature

BACKGROUND

While margin-negative resection remains the cornerstone of therapy for retroperitoneal sarcoma (RPS), the impact of adjuvant chemotherapy (AC) on overall survival (OS) remains poorly understood.

METHODS

The National Cancer Data Base was queried for patients undergoing curative-intent resection of primary non-metastatic RPS (2004-2013). Multivariable modeling identified factors associated with AC receipt. Cox regression identified covariates associated with OS, and AC and surgery alone (SA) cohorts were matched 1:1 by propensity scores based on these covariates. In the propensity-score matched cohort, OS was compared by Kaplan-Meier estimates. Results from this analysis were presented in the context of a review of the existing literature on the impact of AC in resected RPS.

RESULTS

Of 3892 resected RPS patients, 90.0% and 10.0% received SA and AC, respectively. Predictors of AC receipt included younger age, non-Caucasian race, hospital location, histologic grade, adjacent organ invasion, and histologic subtype. The propensity score-matched cohort comprised 767 patients (SA n = 377; AC n = 390); at a median follow-up of 59.2 (IQR 35.0-85.3) months, median OS of the propensity-matched cohort was 53.6 (IQR 22.4-119.5) months. Utilization of AC was associated with significantly worse long-term survival (median OS: 47.8 vs. 68.9 months, p = 0.017; HR 1.30, 95% CI 1.05-1.61). AC was not associated with improved OS in margin-positive (R1/R2) resection, high-grade (G2/G3) and larger (>10 cm) tumors, or in any histologic subtype. Albeit not statistically significant, there was a trend toward improved OS with AC in spindle cell (HR 0.37, 95% CI 0.10-1.38), giant cell (HR 0.82, 95% CI 0.32-2.13), and synovial (HR 0.26, 95% CI 0.05-1.33) sarcoma.

CONCLUSIONS

Data from a large nationwide oncology database and review of the existing literature do not support adjuvant chemotherapy regimens following curative-intent resection of RPS, even in subgroups at high risk of failure (e.g., R1/R2 resection, high-grade or large tumors). The possible benefit of conventional adjuvant regimens in spindle cell, giant cell, and synovial sarcoma should be explored in prospective studies.

Externalized Stents for Pancreatoduodenectomy Provide Value Only in High-Risk Scenarios

BACKGROUND

Evidence suggests externalized trans-anastomotic stents may be beneficial as a fistula mitigation strategy for pancreatoduodenectomy (PD); however, previous studies have not been rigorously risk-adjusted.

METHODS

From 2001 to 2015, PDs were performed at three institutions, with externalized stents placed at the surgeon's discretion. The Fistula Risk Score (FRS) and the Modified Accordion Severity Grading System were used to analyze occurrence and severity of clinically relevant postoperative pancreatic fistula (CR-POPF) across various risk scenarios.

RESULTS

Of 729 PDs, externalized stents were placed during 129 (17.7 %). Overall, CR-POPFs occurred in 77 (10.6 %) patients. The median FRS of patients who received externalized stents was significantly higher compared with patients who did not (6 vs. 3, p < 0.0001). Patients with negligible, low, or moderate CR-POPF risk (FRS 0-6) did not demonstrate improved outcomes with externalized stents; however, among high-risk patients (FRS 7-10), stents were associated with significantly reduced rates of CR-POPF (14.0 vs. 36.4 %, p = 0.031), severe complications (p = 0.039), and hospital stay (p = 0.014) compared with no stents. The average complication burden of CR-POPF was significantly lower for patients with externalized stents (p = 0.035).

CONCLUSION

This multicenter study, the largest comparative analysis of externalized trans-anastomotic stents versus no stent for PD, demonstrates a risk-stratified benefit to externalized stents.

Adjuvant chemotherapy versus chemoradiotherapy in the management of patients with surgically resected duodenal adenocarcinoma: A propensity score-matched analysis of a nationwide clinical oncology database

BACKGROUND

To the authors' knowledge, optimal adjuvant approaches for resected duodenal adenocarcinoma are not well established. Given the significant risk of locoregional disease recurrence, there may be a subset of patients who demonstrate an improvement in overall survival (OS) from the addition of radiotherapy (chemoradiotherapy [CRT]) to an adjuvant chemotherapy regimen.

METHODS

Patients with resected, nonmetastatic duodenal adenocarcinoma who received chemotherapy (694 patients) or CRT (550 patients) were identified in the National Cancer Data Base (1998-2012). Cox regression identified covariates associated with OS. The chemotherapy and CRT cohorts were matched (1:1) by propensity scores based on the likelihood of receiving CRT or the survival hazard from Cox modeling. OS was compared using Kaplan-Meier estimates.

RESULTS

CRT was more frequently used for patients who underwent positive-margin surgical resection (15.9% vs 9.1%; P<.001). At a median follow-up of 79.2 months (interquartile range, 52.9-114.9 months), the median OS of the propensity score-matched cohort was 46.7 months (interquartile range, 18.9 months to not reached). No survival advantage was observed for patients who were treated with adjuvant CRT compared with those treated with adjuvant chemotherapy (median OS: 48.9 months vs 43.5 months [HR, 1.04; 95% confidence interval, 0.88-1.22 (P = .669)]). CRT was not found to be associated with a significant improvement in the median OS after positive-margin surgical resection (133 patients; 27.6 months vs 18.5 months [P = .210]) or in the presence of T4 classification (461 patients; 30.6 months vs 30.4 months [P = .844]) inadequate lymph node staging (584 patients; 40.5 months vs 43.2 months [P = .707]), lymph node positivity (647 patients; 38.3 months vs 34.1 months [P = .622]), or poorly differentiated histology (429 patients; 46.6 months vs 35.7 months [P = .434]).

CONCLUSIONS

The addition of radiation to adjuvant therapy does not appear to significantly improve survival, even in high-risk cases. Cancer 2017;123:967-76. © 2016 American Cancer Society.