Kendrick, Michael L.

BACKGROUND: There is lack of consensus on post-operative surveillance for resected non-invasive intraductal papillary neoplasms (IPMNs). In this study we explored risk factors for subsequent PC in patients with MD-IPMN undergoing partial pancreatectomy. METHODS: We searched the Mayo Clinic surgical pathology database for all cases of resected MD-IPMN between 1997 and 2014. Cases with histologically confirmed main pancreatic duct involvement either isolated or in a mixed pattern with branch-duct involvement were included. Outcomes of PC in the remnant pancreas, and death related to MD-IPMN were assessed with survival analyses (Kaplan–Meier and Cox regression). RESULTS: Among the 179 patients with resected MD-IPMN the incidence of concomitant PC and high-grade dysplasia (HGD) in the resected specimen was 23 and 14%, respectively. The mean duration of follow-up was 4.31 years (range 0.12–13.5 years). Excluding 28 subjects who either underwent initial total pancreatectomy or partial pancreatectomy with surgical margins positive for PC/HGD, the 5-year incidence of subsequent PC was 12%, including 60.6% and 15.6% in those with initial PC and HGD, respectively. The 10-year incidence of PC was 21.2% overall, 60.6% for PC, 38.3% for HGD, and 3.0% for LGD. Risk of subsequent PC was significantly higher for those with initial PC compared with HGD (HR = 4.95, 95% CI: 1.63–15.03, p = 0.005 and for HGD compared with LGD (HR = 11.30, 95% CI: 1.55–82.26, p = 0.017). CONCLUSIONS: Patients with MD-IPMN with PC or HGD undergoing segmental pancreatectomy are at higher risk of subsequent PC and may benefit from post-operative surveillance. The post-operative surveillance intervals in resected MD-IPMNs need to be tailored based on dysplasia grade.

e15703 Background: The aim of this study is to identify prognostic factors and effects of adjuvant therapy for patients with ampullary adenocarcinoma who had pancreatoduodenectomy. Methods: A cohort of 123 consecutive patients underwent pancreatoduodenectomy for ampullary adenocarcinoma from January 1, 2006, through August 31, 2016 at Mayo Clinic in Rochester, MN. Only patients with ampullary carcinoma by pathology review were included and were histologically classified as pancreaticobiliary or intestinal subtypes. Median follow-up duration was 41.0 months. Patient survival and its correlation with patient and tumor variables were tested by univariate and multivariate analysis. Results: Pancreatoduodenectomy was curative-intent in 120 out of 123 patients. All 123 patients underwent radical surgery, 32 patients (26.0%) had laparoscopic pancreatoduodenectomy. Among 123 patients, there were 76 men (61.8%).Median age at diagnosis was 67.2 years. 54 patients (45%) without metastatic disease upon surgery had adjuvant therapy (35 patients had chemotherapy only while 19 patient also had radiation). Median overall survival (OS) was 91.8 months. Poor performance status at disease diagnosis (ECOG > = 1), old age ( > = 70 years), primary tumor infiltration (T), lymph node metastasis (N), and advanced disease stage (TNM) had a significant negative impact on survival (p < 0.05 by univariate analysis). Gender, diabetes at disease diagnosis, laparoscopic surgery approach, number of lymph nodes removed, number of positive lymph nodes, and tumor size did not influence survival. In multivariate analysis, ECOG score > = 1, adjuvant treatment, primary tumor infiltration (T) and lymph node metastasis (N) remained statistically significant. Adjuvant therapy was independently associated with improved disease free survival (P = 0.0388) and overall survival (p = 0.030) for patients with advanced disease (stage IIB and above). Conclusions: Poor performance status and advanced disease stage are associated with decreased survival in patients with ampullary adenocarcinoma. Patients with advanced disease should be considered for adjuvant chemotherapy.

e15045 Background: BRAF V600E mutations are present in 7% of mCRC patients (pts) and portend a poor prognosis. Data guiding initial treatment decisions are limited. This study investigates the management approach and clinical impact of utilizing metastasectomy for pts with BRAF V600E mCRC. Methods: By using prospective clinical and molecular data from Mayo Clinic, pts with BRAF V600E mCRC were analyzed for clinical characteristics, treatment and survival outcomes. Statistical analyses utilized Kaplan-Meier method, Log-rank test, and Cox proportional hazards models. Results: 164 pts with BRAF V600E mCRC were identified between 6/1999-8/2015. Complete follow up data were available for 52 pts. Median age of 65 years, 61% female, ECOG PS ≤ 1, 71% of pts had right sided tumors and 28% presented with liver limited metastasis. Only 7% (4/52) received FOLFOXIRI/BEV (average of 8 cycles). Peripheral neuropathy, pending BRAF status , and prior progression on FOLFOX, were the most common reasons documented for avoiding FOLFOXIRI/BEV. FOLFOX/BEV was the most common 1st line regimen used (32% of pts). Median overall survival (mOS) for all 52 pts was 25 months (mo) with median progression free survival (PFS) of 9.3 mo, reflecting worse survival when compared to BRAF wild-type control patients treated at Mayo Clinic (249 pts, mOS: 43 mo). With median follow up of 18.3 mo, 21 pts who underwent metastasectomy had improved OS (29.1mo vs. 22.7mo, HR = 0.33; CI: 0.12-0.78; p = 0.01) and PFS (13.6mo vs. 6.2mo, HR = 0.53, CI: 0.28-0.97; p = 0.03) when compared to the non-metastasectomy cohort, respectively. In multivariate analysis, metastasectomy remained statistically significant for improved survival outcomes (HR 0.52; 95% CI 0.07-1.02; p = 0.02). Median relapse-free survival after metastasectomy was 9.7 mo (95% CI, 5.5 mo-19.5 mo). Only 2 pts remain disease free at the time of last follow up, with 1 pt without recurrent disease for greater than 2 years (28.9 mo). Conclusions: The use of multimodality therapy incorporating metastasectomy for BRAF V600E mCRC is a critical component for enhanced survival outcomes.

To determine the role of vagal nerves in initiation and modulation of the gastric migrating motor complex (MMC), motor activity was recorded in four dogs before and after total abdominal vagotomy during fasting, after exogenous intravenous motilin and insulin, and after feeding. After vagotomy, a temporally coordinated cyclic gastric and small bowel MMC persisted with an unchanged period. During gastric phase III, vagotomy decreased number of contractions (42 ± 4 vs. 16 ± 2), number of groupings of contractions (14 ± 1 vs. 7 ± 1), and motility index (12 ± 1 vs. 10 ± 1) and increased the duration between groupings (1 ± 1 vs. 3 ± 1 min) ( P< 0.05 in each). Before and after vagotomy, motilin and insulin induced a premature MMC with minor changes in contractile pattern. A 200-g liver meal but not a 50-g liver meal inhibited the gastric MMC after vagotomy. A cyclic MMC persisted after vagotomy, but the contractile pattern during gastric phase III was altered. After a short recovery period, vagal innervation to the stomach modulates the pattern but not the presence of gastric interdigestive motility during phase III.

Abstract Background BRAF V600E mutations are present in 8%–10% of patients with metastatic colorectal cancer (mCRC) and portend poor prognosis. This study investigated the impact of metastasectomy for patients with BRAF V600E mCRC. Subjects, Materials, and Methods Using prospective clinical and molecular data, patients with BRAF V600E mCRC were analyzed for clinical characteristics and survival. Statistical analyses utilized the Kaplan-Meier method, log-rank test, and Cox proportional hazard models. Results Fifty-two patients were identified between July 1, 2008, and January 4, 2016. Patient characteristics included median age 65 years, 61% female, Eastern Cooperative Oncology Group performance status ≤1, 71% with right-sided tumors, and 28% with liver-limited metastasis. In the first-line setting, 7% (4/52) received fluorouracil, leucovorin, oxaliplatin, and irinotecan (FOLFOXIRI)/bevacizumab (BEV) and 81% were treated with doublet chemotherapy consisting of fluoropyrimidine, oxaliplatin, and BEV. Median overall survival (OS) for all 52 patients was 25 months with median progression-free survival (PFS) of 9.3 months. With median follow-up of 18.3 months, 21 patients underwent metastasectomy with longer OS (29.1 months vs. 22.7 months, hazard ratio [HR] = 0.33; confidence interval [CI], 0.12–0.78; p = .01) and PFS (13.6 months vs. 6.2 months, HR = 0.53, CI, 0.28–0.97; p = .03) compared with the non-metastasectomy cohort. In multivariate analysis, metastasectomy remained significant for improved survival outcomes (HR = 0.52; 95% CI, 0.07–1.02; p = .02). Median disease-free survival after metastasectomy was 9.7 months (95% CI, 5.5–19.5). Two patients remain disease-free at the time of last follow-up, with one patient without relapse for greater than 2 years (28.9 months). Conclusion Multimodality therapy incorporating metastasectomy for BRAF V600E mCRC should be considered and might be associated with improved overall survival in select patients. Implications for Practice BRAF V600E metastatic colorectal cancer (mCRC) represents an extremely difficult molecular subset of colorectal cancer to treat. To date, this subset remains refractory to standard chemotherapies, prompting extensive clinical investigation regarding novel treatment approaches and targeted modalities. While the use of metastasectomy for expanded RAS wild-type and RAS mutated mCRC has resulted in improved overall survival for select patients, utilization of metastasectomy in patients with BRAF V600E mCRC remains controversial. This article explores the authors' experience with BRAF V600E mCRC to ascertain whether a multidisciplinary approach incorporating metastasectomy for well-selected patients improves overall survival.

AbstractBackgroundAnimal studies have increasingly highlighted the role of macrophages in the development of delayed gastric emptying. However, their role in the pathophysiology of human gastroparesis is unclear. Our aim was to determine changes in macrophages and other cell types in the gastric antrum muscularis propria of patients with diabetic and idiopathic gastroparesis.MethodsFull thickness gastric antrum biopsies were obtained from patients enrolled in the Gastroparesis Clinical Research Consortium (11 diabetic, 6 idiopathic) and 5 controls. Immunolabeling and quantitative assessment was done for interstitial cells of Cajal (ICC) (Kit), enteric nerves protein gene product 9.5, neuronal nitric oxide synthase, vasoactive intestinal peptide, substance P, tyrosine hydroxylase), overall immune cells (CD45) and anti‐inflammatory macrophages (CD206). Gastric emptying was assessed using nuclear medicine scintigraphy and symptom severity using the Gastroparesis Cardinal Symptom Index.ResultsBoth diabetic and idiopathic gastroparesis patients showed loss of ICC as compared to controls (Mean [standard error of mean]/hpf: diabetic, 2.28 [0.16]; idiopathic, 2.53 [0.47]; controls, 6.05 [0.62]; P=.004). Overall immune cell population (CD45) was unchanged but there was a loss of anti‐inflammatory macrophages (CD206) in circular muscle (diabetic, 3.87 [0.32]; idiopathic, 4.16 [0.52]; controls, 6.59 [1.09]; P=.04) and myenteric plexus (diabetic, 3.83 [0.27]; idiopathic, 3.59 [0.68]; controls, 7.46 [0.51]; P=.004). There was correlation between the number of ICC and CD206‐positive cells (r=.55, P=.008). Enteric nerves (PGP9.5) were unchanged: diabetic, 33.64 (3.45); idiopathic, 41.26 (6.40); controls, 46.80 (6.04).ConclusionLoss of antral CD206‐positive anti‐inflammatory macrophages is a key feature in human gastroparesis and it is associates with ICC loss.

Abstract Purpose: Data on laparoscopic totally extraperitoneal inguinal hernia repairs (TEP-IHRs) suggest that approximately 250 operations are needed to gain mastery, but the annual volume required to maintain high-quality outcomes is unknown. Materials and Methods: A retrospective review was performed of every patient undergoing a TEP-IHR at the Mayo Clinic (Rochester, MN) from 1995 to 2011. Analysis focused on the annual volume of 21 staff surgeons and their specific patient outcomes broken up into three groups: Group 1 (G1) ( n = 1 surgeon) performed >30 repairs per year; Group 2 (G2) ( n = 3 surgeons), 15–30 repairs; and Group 3 (G3) ( n = 17), <15 repairs. Results: In total, 1601 patients underwent 2410 TEP-IHRs, with no significant patient demographic differences among groups. Greater annual surgeon volume (G1 > G2 > G3) was associated with improved outcomes as shown by the respective rates for intra- (1%, 2.6%, and 5.6%) and postoperative (13%, 27%, and 36%) complications, need for overnight stay (17%, 23%, and 29%), and hernia recurrence (1%, 4%, and 4.3%) (all P < .05). Surgeons with greater annual operative volumes were more likely to operate on patients with bilateral and recurrent hernias. Surgeons performing at least 15 repairs per year (G1 and G2) showed improvements in quality metrics over time. Conclusions: Annual operative volumes of >30 repairs per year are associated with the highest quality outcomes for TEP-IHR. Operative volumes of at least 15 repairs per year are associated with improvements in quality metrics over time. Mentorship and operative assistance of low-volume TEP-IHR surgeons may be useful in improving patient outcomes.