Predictors and benefits of multiagent chemotherapy for pancreatic adenocarcinoma: Timing matters.

INTRODUCTION: Adjuvant (A) multiagent chemotherapy (MC) is the standard of care for patients with pancreatic adenocarcinoma (PDAC). Tolerating MC following a morbid operation may be difficult, thus neoadjuvant (NA) treatment is preferable. This study examined how the timing of chemotherapy was related to the regimen given and ultimately the overall survival (OS). METHODS: The National Cancer Database was queried from 2006 to 2017 for nonmetastatic PDAC patients who underwent surgical resection and received MC or single-agent chemotherapy (SC) pre- or postresection. Predictors of receiving MC were determined using multivariable logistic regression. Five-year OS was evaluated using the Kaplan-Meier and Cox proportional hazards model. RESULTS: A total of 12,440 patients (NA SC, n = 663; NA MC, n = 2313; A SC, n = 6152; A MC, n = 3312) were included. MC utilization increased from 2006-2010 to 2011-2017 (33.1%-49.7%; odds ratio [OR]: 0.59; p < 0.001). Younger age, fewer comorbidities, higher clinical stage, and larger tumor size were all associated with receipt of MC (all p < 0.001), but NA treatment was the greatest predictor (OR 5.18; 95% confidence interval [CI]: 4.63-5.80; p < 0.001). MC was associated with increased median 5-year OS (26.0 vs. 23.9 months; hazard ratio [HR]: 0.92; 95% CI: 0.88-0.96) and NA MC was associated with the highest survival (28.2 months) compared to NA SC (23.3 months), A SC (24.0 months), and A MC (24.6 months; p < 0.001). CONCLUSION: Use and timing of MC contribute to OS in PDAC with an improved 5-year OS compared to SC. The greatest predictor of receiving MC was being given as NA therapy and the greatest survival benefit was the NA MC subgroup. Randomized studies evaluating the timing of effective MC in PDAC are needed.

Standardization of Colon Resection for Cancer: An Overview of the American College of Surgeons Commission on Cancer Standard 5.6.

The purpose of this editorial is to review the American College of Surgeons Commission on Cancer Standard 5.6, which pertains to curative intent colon resections performed for cancer. We first provide a broad overview of the Operative Standard, followed by the underlying rationale, technical components, and documentation requirements.

SAGES/AHPBA guidelines for the use of microwave and radiofrequency liver ablation for the surgical treatment of hepatocellular carcinoma or colorectal liver metastases less than 5 cm.

BACKGROUND: Primary hepatocellular carcinoma (HCC) and colorectal liver metastases (CRLM) represent the liver's two most common malignant neoplasms. Liver-directed therapies such as ablation have become part of multidisciplinary therapies despite a paucity of data. Therefore, an expert panel was convened to develop evidence-based recommendations regarding the use of microwave ablation (MWA) and radiofrequency ablation (RFA) for HCC or CRLM less than 5 cm in diameter in patients ineligible for other therapies. METHODS: A systematic review was conducted for six key questions (KQ) regarding MWA or RFA for solitary liver tumors in patients deemed poor candidates for first-line therapy. Subject experts used the GRADE methodology to formulate evidence-based recommendations and future research recommendations. RESULTS: The panel addressed six KQs pertaining to MWA vs. RFA outcomes and laparoscopic vs. percutaneous MWA. The available evidence was poor quality and individual studies included both HCC and CRLM. Therefore, the six KQs were condensed into two, recognizing that these were two disparate tumor groups and this grouping was somewhat arbitrary. With this significant limitation, the panel suggested that in appropriately selected patients, either MWA or RFA can be safe and feasible. However, this recommendation must be implemented cautiously when simultaneously considering patients with two disparate tumor biologies. The limited data suggested that laparoscopic MWA of anatomically more difficult tumors has a compensatory higher morbidity profile compared to percutaneous MWA, while achieving similar overall 1-year survival. Thus, either approach can be appropriate depending on patient-specific factors (very low certainty of evidence). CONCLUSION: Given the weak evidence, these guidelines provide modest guidance regarding liver ablative therapies for HCC and CRLM. Liver ablation is just one component of a multimodal approach and its use is currently limited to a highly selected population. The quality of the existing data is very low and therefore limits the strength of the guidelines.

Incidence of and Risk Factors for Incisional Hernia After Hepatectomy for Colorectal Liver Metastases.

BACKGROUND: Incisional hernia (IH) is common after major abdominal surgery; however, the incidence after hepatectomy for cancer has not been described. We analyzed incidence of and risk factors for IH after hepatectomy for colorectal liver metastases (CLM). METHODS: Patients who underwent open hepatectomy with midline or reverse-L incision for CLM at a single institution between 2010 and 2018 were retrospectively analyzed. Postoperative CT scans were reviewed to identify IH and the time from hepatectomy to hernia. Cumulative IH incidence was calculated using competing risk analysis. Risk factors were assessed using Cox proportional hazards model analysis. The relationship between IH incidence and preoperative body mass index (BMI) was estimated using a generalized additive model. RESULTS: Among 470 patients (median follow-up: 16.9 months), IH rates at 12, 24, and 60 months were 41.5%, 51.0%, and 59.2%, respectively. Factors independently associated with IH were surgical site infection (HR: 1.54, 95% CI 1.16-2.06, P = 0.003) and BMI > 25 kg/m2 (HR: 1.94, 95% CI 1.45-2.61, P < 0.001). IH incidence was similar in patients undergoing midline and reverse-L incisions and patients who received and did not receive a bevacizumab-containing regimen. The 1-year IH rate increased with increasing number of risk factors (zero: 22.2%; one: 46.8%; two: 60.3%; P < 0.001). Estimated IH incidence was 10% for BMI of 15 kg/m2 and 80% for BMI of 40 kg/m2. CONCLUSION: IH is common after open hepatectomy for CLM, particularly in obese patients and patients with surgical site infection. Surgeons should consider risk-mitigation strategies, including alternative fascial closure techniques.

Impact of Adherence to Operative Standards and Stage-Specific Guideline-Recommended Therapy in Nonmetastatic Pancreatic Adenocarcinoma.

BACKGROUND: Achieving optimal surgical outcomes in pancreatic adenocarcinoma requires a combination of both curative-intent resection to oncologic standards and stage-specific neoadjuvant or adjuvant therapy. This investigation sought to examine factors associated with receipt of standard-adherent surgery (SAS) and guideline-recommended therapy (GRT) and determine the impact of compliance on patient survival. PATIENTS AND METHODS: From the 2006-2016 National Cancer Database, 21,304 patients underwent resection for nonmetastatic pancreatic adenocarcinoma. SAS was defined as pancreatic resection with negative margins and ≥ 15 lymph nodes examined. Stage-specific GRT was defined by current National Comprehensive Cancer Network guidelines. Multivariable models were used to determine predictors of adherence to SAS and GRT and prognostic impact on overall survival. RESULTS: Overall, SAS was achieved in 39% and GRT in 65% of patients, but only 30% received both SAS and GRT. Increasing age, minority race, uninsured status, and greater comorbidities were associated with a decreased odds of receiving both SAS and GRT (all p < 0.05). SAS (HR 0.79; CI 0.76-0.81; p < 0.001) and GRT (HR 0.67; CI 0.65-0.69; p < 0.001) were each independently associated with a survival advantage. Receipt of both SAS and GRT was associated with significant improvement in median OS compared with receiving neither (2.2 years vs 1.1 years; p < 0.001) which was independently associated with a 78% increased risk of death (HR 1.78; CI 1.70-1.86; p < 0.001). CONCLUSIONS: Despite survival benefits associated with adherence to operative standards and receipt of guideline-recommended therapy, compliance remains poor. Future efforts must be directed toward improved education and implementation efforts around both operative standards and therapy guidelines.

Tumor infiltrating lymphocytes as an endpoint in cancer vaccine trials.

Checkpoint inhibitors have invigorated cancer immunotherapy research, including cancer vaccination. Classic early phase trial design and endpoints used in developing chemotherapy are not suited for evaluating all forms of cancer treatment. Peripheral T cell response dynamics have demonstrated inconsistency in assessing the efficacy of cancer vaccination. Tumor infiltrating lymphocytes (TILs), reflect the local tumor microenvironment and may prove a superior endpoint in cancer vaccination trials. Cancer vaccines may also promote success in combination immunotherapy treatment of weakly immunogenic tumors. This review explores the impact of TILs as an endpoint for cancer vaccination in multiple malignancies, summarizes the current literature regarding TILs analysis, and discusses the challenges of providing validity and a standardized implementation of this approach.

SAGES/AHPBA guidelines for the use of minimally invasive surgery for the surgical treatment of colorectal liver metastases (CRLM).

BACKGROUND: Colorectal liver metastases (CRLM) occur in roughly half of patients with colorectal cancer. Minimally invasive surgery (MIS) has become an increasingly acceptable and utilized technique for resection in these patients, but there is a lack of specific guidelines on the use of MIS hepatectomy in this setting. A multidisciplinary expert panel was convened to develop evidence-based recommendations regarding the decision between MIS and open techniques for the resection of CRLM. METHODS: Systematic review was conducted for two key questions (KQ) regarding the use of MIS versus open surgery for the resection of isolated liver metastases from colon and rectal cancer. Evidence-based recommendations were formulated using the GRADE methodology by subject experts. Additionally, the panel developed recommendations for future research. RESULTS: The panel addressed two KQs, which pertained to staged or simultaneous resection of resectable colon or rectal metastases. The panel made conditional recommendations for the use of MIS hepatectomy for both staged and simultaneous resection when deemed safe, feasible, and oncologically effective by the surgeon based on the individual patient characteristics. These recommendations were based on low and very low certainty of evidence. CONCLUSIONS: These evidence-based recommendations should provide guidance regarding surgical decision-making in the treatment of CRLM and highlight the importance of individual considerations of each case. Pursuing the identified research needs may help further refine the evidence and improve future versions of guidelines for the use of MIS techniques in the treatment of CRLM.

Setting the Standard for Cutaneous Melanoma Wide Local Excision: An Overview of the American College of Surgeons Commission on Cancer Standard 5.5.

The purpose of this article is to review the objectives of the American College of Surgeons Commission on Cancer Operative Standards with a specific focus on Standard 5.5, which pertains to curative intent wide local excision of primary cutaneous melanoma lesions. We review the details and rationale of the standard itself, including its requirement to include specific elements and responses in synoptic format in operative reports.

Prognosis Associated With CA19-9 Response Dynamics and Normalization During Neoadjuvant Therapy in Resected Pancreatic Adenocarcinoma.

OBJECTIVE: To characterize associations between carbohydrate antigen 19-9 (CA19-9) dynamics during neoadjuvant therapy (NT) and survival for patients with pancreatic ductal adenocarcinoma (PDAC). BACKGROUND: Although normalization of CA19-9 during NT is associated with improved outcomes following PDAC resection, we hypothesize that CA19-9 dynamics during NT can improve prognostication. METHODS: Characteristics for patients with PDAC undergoing NT (July 2011-October 2018) with ≥3 CA19-9 results (bilirubin<2mg/dL) were collected and grouped by CA19-9 dynamics. Nonproducers (<1 U/ml) were excluded, and normal was ≤35 U/ml. Postresection survival was compared among groups. RESULTS: Of 431 patients, 166 had eligible CA19-9 values. Median baseline CA19-9 was 98 U/ml. Overall 2-year postresection recurrence-free survival (RFS) and overall survival (OS) were 37% and 63%, respectively. Patients with normalization (53%) had improved 2-year RFS (47% vs. 28%, P = 0.01) and OS (75% vs. 49%, P = 0.01). CA19-9 dynamics during NT were analyzed by shape, direction, and normalization creating response types ("A-B-C-D-E"). Type A was "Always" decreasing to normalization, B "Bidirectional" with eventual normalization, C "Consistently" normal, D any "Decrease" without normalization, and E "Elevating" without normalization. Types A and B responses were associated with the longest postresection 2-year RFS (51% and 56%) and OS (75% and 92%, respectively) whereas Types D and E had the worst outcomes. After adjusting for node-positivity, perineural invasion, and margin-positivity, CA19-9 response types were independently associated with both RFS and OS, and predicted outcomes are better than CA19-9 normalization alone (likelihood ratio test RFS P < 0.001, OS P = 0.01). CONCLUSIONS: This novel A-B-C-D-E classification of CA19-9 dynamics during NT was associated with postresection outcomes more precisely than CA19-9 normalization alone.

Prolonged Survival Following Intra-abdominal Mycobacterium abscessus Infection Without Antimicrobial Therapy or Surgical Intervention.

Management of Mycobacterium abscessus infection involves prolonged multidrug antibiotic therapy with surgical resection indicated in extensive disease and abscesses. We report a case of post-surgical intra-abdominal M. abscessus infection with prolonged survival and radiographic resolution without intervention. A 51-year-old female who had a prolonged hospital stay with multiple surgeries following a complicated laparoscopic sleeve gastrectomy developed multiple M. abscessus intra-abdominal and abdominal wall abscesses with cutaneous fistulae. She was started on a multidrug antibiotic regimen. However, the patient terminated the regimen after 4 weeks due to intolerable side effects and was transitioned to hospice care. She showed steady clinical improvement with radiographic resolution of the abscesses over the next year. In the context of the limited understanding of these infections, our finding is notable, given that in this period, she avoided potential hospitalizations, life altering side effects of prolonged antimicrobial therapy, and complications from more surgeries.

Impact of Mediating and Confounding Variables on the Volume-Outcome Association in the Treatment of Pancreatic Cancer.

BACKGROUND: High-volume centers (HVC), academic centers (AC), and longer travel distances (TD) have been associated with improved outcomes for patients undergoing surgery for pancreatic adenocarcinoma (PAC). Effects of mediating variables on these associations remain undefined. The purpose of this study is to examine the direct effects of hospital volume, facility type, and travel distance on overall survival (OS) in patients undergoing surgery for PAC and characterize the indirect effects of patient-, disease-, and treatment-related mediating variables. PATIENTS AND METHODS: Using the National Cancer Database, patients with non-metastatic PAC who underwent resection were stratified by annual hospital volume (< 11, 11-19, and ≥ 20 cases/year), facility type (AC versus non-AC), and TD (≥ 40 versus < 40 miles). Associations with survival were evaluated using multiple regression models. Effects of mediating variables were assessed using mediation analysis. RESULTS: In total, 19,636 patients were included. Treatment at HVC or AC was associated with lower risk of death [hazard ratio (HR) 0.90, confidence interval (CI) 0.88-0.92; HR 0.89, CI 0.86-0.91, respectively]. TD did not impact OS. Patient-, disease-, and treatment-related variables explained 25.5% and 41.8% of the survival benefit attained from treatment at HVC and AC, reducing the survival benefit directly attributable to each variable to 4.9% and 6.4%, respectively. CONCLUSIONS: Treatment of PAC at HVC and AC was associated with improved OS, but the magnitude of this benefit was less when mediating variables were considered. From a healthcare utilization and cost-resource perspective, further research is needed to identify patients who would benefit most from selective referral to HVC or AC.

Prospective Study of Perioperative Circulating Tumor DNA Dynamics in Patients Undergoing Hepatectomy for Colorectal Liver Metastases.

OBJECTIVE: To evaluate the association of perioperative ctDNA dynamics on outcomes after hepatectomy for CLM. SUMMARY BACKGROUND DATA: Prognostication is imprecise for patients undergoing hepatectomy for CLM, and ctDNA is a promising biomarker. However, clinical implications of perioperative ctDNA dynamics are not well established. METHODS: Patients underwent curative-intent hepatectomy after preoperative chemotherapy for CLM (2013-2017) with paired prehepatectomy/postoperative ctDNA analyses via plasma-only assay. Positivity was determined using a proprietary variant classifier. Primary endpoint was recurrence-free survival (RFS). Median follow-up was 55 months. RESULTS: Forty-eight patients were included. ctDNA was detected before and after surgery (ctDNA+/+) in 14 (29%), before but not after surgery (ctDNA+/-) in 19 (40%), and not at all (ctDNA-/-) in 11 (23%). Adverse tissue somatic mutations were detected in TP53 (n = 26; 54%), RAS (n = 23; 48%), SMAD4 (n = 5; 10%), FBXW7 (n = 3; 6%), and BRAF (n = 2; 4%). ctDNA+/+ was associated with worse RFS (median: ctDNA+/+, 6.0 months; ctDNA+/-, not reached; ctDNA-/-, 33.0 months; P = 0.001). Compared to ctDNA+/+, ctDNA+/- was associated with improved RFS [hazard ratio (HR) 0.24 (95% confidence interval (CI) 0.1-0.58)] and overall survival [HR 0.24 (95% CI 0.08-0.74)]. Adverse somatic mutations were not associated with survival. After adjustment for prehepatectomy chemotherapy, synchronous disease, and ≥2 CLM, ctDNA+/- and ctDNA-/- were independently associated with improved RFS compared to ctDNA+/+ (ctDNA+/-: HR 0.21, 95% CI 0.08-0.53; ctDNA-/-: HR 0.21, 95% CI 0.08-0.56). CONCLUSIONS: Perioperative ctDNA dynamics are associated with survival, identify patients with high recurrence risk, and may be used to guide treatment decisions and surveillance after hepatectomy for patients with CLM.

Minimally invasive versus open distal pancreatectomy: a matched analysis using ACS-NSQIP.

BACKGROUND: Minimally invasive distal pancreatectomy (MIDP) is gaining popularity due to improved perioperative outcomes over open distal pancreatectomy (ODP). The purpose of this study is to compare outcomes of MIDP and ODP using patients within a nationwide cohort. METHODS: The American College of Surgeons' National Quality Improvement Program (2014-2018) was used to evaluate incidence of post-operative pancreatic fistula (POPF) as well as 30-day composite major morbidity for patients undergoing MIDP vs. ODP. Matching was performed with a Mahalanobis-distance model for demographic characteristics, preoperative risk factors, and benign versus malignant pathology. Outcomes were assessed via weighted multiple logistic regression. RESULTS: A total of 3940 patients underwent distal pancreatectomy (1978 MIDP, 1962 ODP). After matching, 2985 patients were included (1978 MIDP, 1007 ODP). The rates of major morbidity (8.65% MIDP vs. 9.76% ODP, p = 0.37) were similar between groups. The MIDP group was found to have significantly decreased length of stay (5.6 vs. 7 days, p ≤ 0.001), but greater rates (12.54% MIDP vs. 9.35% ODP, p = 0.02) of post-operative fistula. CONCLUSIONS: When matched for baseline patient characteristics, MIDP was associated with shorter length of hospitalization with similar rates of morbidity compared to ODP. However, MIDP was associated with significantly increased rates of POPF. Further studies are needed to investigate this difference in POPF rate, and determine how to optimize MIDP surgical technique to reduce this risk.

Divergent clinical outcomes in a phase 2B trial of the TLPLDC vaccine in preventing melanoma recurrence and the impact of dendritic cell collection methodology: a randomized clinical trial.

BACKGROUND: A randomized, double-blind, placebo-controlled phase 2b trial of the tumor lysate, particle-loaded, dendritic cell (TLPLDC) vaccine was conducted in patients with resected stage III/IV melanoma. Dendritic cells (DCs) were harvested with and without granulocyte-colony stimulating factor (G-CSF). This analysis investigates differences in clinical outcomes and RNA gene expression between DC harvest methods. METHODS: The TLPLDC vaccine is created by loading autologous tumor lysate into yeast cell wall particles (YCWPs) and exposing them to phagocytosis by DCs. For DC harvest, patients had a direct blood draw or were pretreated with G-CSF before blood draw. Patients were randomized 2:1 to receive TLPLDC or placebo. Differences in disease-free survival (DFS) and overall survival (OS) were evaluated. RNA-seq analysis was performed on the total RNA of TLPLDC + G and TLPLDC vaccines to compare gene expression between groups. RESULTS: 144 patients were randomized: 103 TLPLDC (47 TLPLDC/56 TLPLDC + G) and 41 placebo (19 placebo/22 placebo + G). Median follow-up was 27.0 months. Both 36-month DFS (55.8% vs. 24.4% vs. 30.0%, p = 0.010) and OS (94.2% vs. 69.8% vs. 70.9%, p = 0.024) were improved in TLPLDC compared to TLPLDC + G or placebo, respectively. When compared to TLPLDC + G vaccine, RNA-seq from TLPLDC vaccine showed upregulation of genes associated with DC maturation and downregulation of genes associated with DC suppression or immaturity. CONCLUSIONS: Patients receiving TLPLDC vaccine without G-CSF had improved OS and DFS. Outcomes remained similar between patients receiving TLPLDC + G and placebo. Direct DC harvest without G-CSF had higher expression of genes linked to DC maturation, likely improving clinical efficacy.

Circulating Tumor DNA: Towards More Individualized Treatment for Patients with Resectable Colorectal Cancer.

PURPOSE: Despite curative-intent treatment, recurrence is common for patients with colorectal cancer (CRC).  Currently, prediction of disease recurrence and prognostication following surgery is based upon vague clinical factors and more precise and dynamic biomarkers for risk stratification and treatment decisions are urgently needed.  Circulating tumor DNA (ctDNA) is a promising biomarker for patients undergoing treatment for resectable CRC. METHODS: In this review, we provide an overview of the data supporting current uses of ctDNA for CRC, including localized CRC and resectable colorectal liver metastases (CLM), as well as descriptions of important ongoing clinical trials using ctDNA in the care of patients with CRC. RESULTS: The detection of ctDNA following curative-intent therapy is associated with disease recurrence, and multiple trials are investigating its role in determining need and duration for adjuvant therapy for localized CRC. In addition, ctDNA reliably predicts prognosis for patients with CLM, with trials underway studying ctDNA-guided treatment sequencing and intensity. CONCLUSION: The detection of ctDNA is a sensitive and dynamic biomarker for disease recurrence in CRC. Many investigations are underway into ctDNA's potential role in surveillance and treatment algorithms, and it has the potential to become a critical biomarker to determine individualized strategies for treatment sequencing, choice, and duration of therapies.