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"Vollmer, Charles M."
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Paul Greig, MD – Professor of Surgery, University of Toronto
2023
Dr. Paul Greig is an icon of surgical education, transplantation, hepatobiliary surgery and Canadian surgery. Dr. Greig has trained experts in these fields all over the world and is regarded as one of the most important surgical educators in the past 25 years.
Journal Article
Risk Prediction for Development of Pancreatic Fistula Using the ISGPF Classification Scheme
by
Vollmer, Charles M.
,
Pratt, Wande B.
,
Callery, Mark P.
in
Abdominal Surgery
,
Aged
,
Biological and medical sciences
2008
Background:
The International Study Group on Pancreatic Fistula (ISGPF) classification scheme has become a useful system for characterizing the clinical impact of pancreatic fistula. We sought to identify predictive factors that predispose patients to fistula, specifically those with clinical relevance (grades B/C), and to describe the clinical and economic significance of risk stratification within this framework.
Methods:
Overall, 233 consecutive pancreatoduodenectomies were performed between October 2001 and March 2007 in our institution. Pancreatic fistula is defined according to the ISGPF classification scheme. Logistic regression analysis was performed to identify risk factors for pancreatic fistula development. These features were then analyzed to determine whether additive risk severity equates to worsening clinical and economic impact.
Results:
Fistulas of any extent occurred in 60 patients, but only 31 (14%) were clinically relevant. There are no identifiable risk factors for grade A biochemical fistulas. Multivariate analysis shows that small pancreatic duct size (<3 mm); soft gland texture; ampullary, duodenal, cystic, or islet cell pathology; and increased intraoperative blood loss (> 1,000 ml) are associated with clinically relevant fistulae. An additive effect is further illustrated, in which clinical and economic outcomes progressively worsen as risk profile increases. Each additional risk factor increases the odds of developing a clinically relevant fistula by 52%.
Conclusions:
For pancreatoduodenectomy, small duct size; soft gland texture; ampullary, duodenal, cystic, or islet cell pathology; and increased intraoperative blood loss are convincing risk factors for the development clinically relevant fistulae as judged by ISGPF classification. As risk profile accrues, patients suffer more complications, encounter longer hospital stays, and incur greater hospital costs. These outcomes can be predicted in the operating room through accurate delineation of high-risk glands.
Journal Article
Exploring the role of quality of life in surgical decision making for patients undergoing pancreatectomy
2025
The influence of baseline health-related quality of life (HRQoL) on peri-operative outcomes in pancreatobiliary (PB) patients is not well established. This study investigated the impact of baseline HRQoL on peri-operative outcomes and the effect of surgery on HRQoL.
A secondary post-hoc analysis of a multicenter trial (2011–2016) assessed PB patients undergoing pancreatectomy. Pre-operative and 30-day post-operative FACT-G surveys were analyzed. Logistic regressions determined associations between baseline HRQoL scores and 60-day major complications. Subgroup analysis evaluated change in HRQoL (pre-operative to 30-day scores).
Among 391 patients, higher baseline HRQoL (FACT-G overall OR 0.54,p = 0.04) was associated with decreased likelihood of developing major complications. Surgery resulted in improvement in HRQoL for patients with chronic pancreatitis (10.2 points) compared to other pathologies (−7 to 3.9 points).
Baseline HRQoL was associated with post-operative complications and HRQoL significantly improved for patients with chronic pancreatitis, highlighting the importance of HRQoL on patient-centered outcomes.
•Lower quality of life predicts major complications after pancreatobiliary surgery.•Patients with chronic pancreatitis had greatest improvement in QoL after surgery.•Baseline quality of life assessments may aid in pre-operative risk stratification.
Journal Article
Identification of Patients for Adjuvant Therapy After Resection of Carcinoma of the Extrahepatic Bile Ducts: A Propensity Score-Matched Analysis
by
Roses, Robert E.
,
Vollmer, Charles M.
,
Datta, Jashodeep
in
Adjuvant therapy
,
Aged
,
Antineoplastic Combined Chemotherapy Protocols - therapeutic use
2017
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.
Journal Article
The Landmark Series: Mitigation of the Postoperative Pancreatic Fistula
2021
Pancreatic fistula has been the defining complication and challenge of pancreatic surgery. Better awareness and mitigation of postoperative pancreatic fistulas has led to significant improvements in morbidity and mortality of pancreatic surgery. The definition and management of pancreatic fistulas has sequentially progressed over the last three decades; the literature ranges from retrospective, observational studies to prospective multicenter randomized controlled trials. The landmark literature contributions driving the perioperative management of pancreatic fistulas are detailed in this article.
Journal Article
A Multi-Institutional External Validation of the Fistula Risk Score for Pancreatoduodenectomy
by
Vollmer, Charles M.
,
Pratt, Wande B.
,
Drebin, Jeffrey A.
in
2013 SSAT Plenary Presentation
,
Clinical outcomes
,
Female
2014
Background
The Fistula Risk Score (FRS), a ten-point scale that relies on weighted influence of four variables, has been shown to effectively predict clinically relevant postoperative pancreatic fistula (CR-POPF) development and its consequences after pancreatoduodenectomy (PD). The proposed FRS demonstrated excellent predictive capacity; however, external validation of this tool would confirm its universal applicability.
Methods
From 2001 to 2012, 594 PDs with pancreatojejunostomy reconstructions were performed at three institutions. POPFs were graded by International Study Group on Pancreatic Fistula standards as grades A, B, or C. The FRS was calculated for each patient, and clinical outcomes were evaluated across four discrete risk zones as described in the original work. Receiver operator curve analysis was performed to judge model validity.
Results
One hundred forty-two patients developed any sort of POPF, of which 68 were CR-POPF (11.4 % overall; 8.9 % grade B, 2.5 % grade C). Increasing FRS scores (0–10) correlated well with CR-POPF development (
p
< 0.001) with a C-statistic of 0.716. When segregated by discrete FRS-risk groups, CR-POPFs occurred in low-, moderate-, and high-risk patients, 6.6, 12.9, and 28.6 % of the time, respectively (
p
< 0.001). Clinical outcomes including complications, length of stay, and readmission rates also increased across risk groups.
Conclusion
This multi-institutional experience confirms the Fistula Risk Score as a valid tool for predicting the development of CR-POPF after PD. Patients devoid of any risk factors did not develop a CR-POPF, and the rate of CR-POPF approximately doubles with each subsequent risk zone. The FRS is validated as a strongly predictive tool, with widespread applicability, which can be readily incorporated into common clinical practice and research analysis.
Journal Article
Evolving Treatment Strategies for Gallbladder Cancer
by
Vollmer, Charles M.
,
Pawlik, Timothy M.
,
Hueman, Matthew T.
in
Combined Modality Therapy
,
Gallbladder Neoplasms - diagnosis
,
Gallbladder Neoplasms - therapy
2009
Gallbladder cancer is an uncommon cancer that has traditionally been associated with a poor prognosis. In the era of laparoscopic cholecystectomy, incidental gallbladder cancer has dramatically increased and now constitutes the major way patients present with gallbladder cancer. While patients with incidental gallbladder cancer have a better survival than patients with nonincidental gallbladder cancer, incidental gallbladder cancer can be associated with a varied prognosis. Imaging with computed tomography (CT), magnetic resonance imaging (MRI), and [18]F-fluorodeoxyglucose (FDG) positron emission tomography (PET), as well as diagnostic laparoscopy, all have varying roles in the workup of patients with incidental gallbladder cancer. For patients with T1b, T2, and T3 incidental gallbladder cancer re-resection is generally recommended. At re-exploration, many patients with incidental gallbladder cancer will have residual disease. Definitive oncologic management requires re-resection of the liver, portal lymphadenectomy, and attention to the common bile duct. The extent of the hepatic resection should be dictated by the ability to achieve a microscopically negative (R0) margin. Routine resection of the common bile duct is unnecessary but should be undertaken in the setting of a positive cystic duct margin. If an incidental gallbladder cancer is discovered at the time of surgery, whether the surgeon should directly proceed with a more definitive oncologic operation should depend on the surgeon’s skill-set and experience. Gallbladder cancer has a propensity to recur. Although data for adjuvant therapy following resection are limited, some data do suggest a survival benefit for adjuvant chemoradiation therapy. Management of patients with gallbladder cancer requires a multidisciplinary approach with input from a surgeon skilled in hepatobiliary surgery.
Journal Article
Evolving the Paradigm of Early Drain Removal Following Pancreatoduodenectomy
by
Seykora, Thomas F.
,
Bassi, Claudio
,
Vollmer, Charles M.
in
2018 SSAT Plenary Presentation
,
Aged
,
Amylases - analysis
2019
Background
Recent data illustrates improved outcomes when adhering to early drain removal following pancreatoduodenectomy (PD). This study aims to explore the potential benefits of expanding the timeframe for early drain removal.
Methods
Six hundred forty PDs were originally managed by selective drain placement and early removal. Outcomes were reappraised in the framework of a novel proposal; intraoperative drains were omitted based on a low-risk profile (Fistula Risk Score 0–2), followed by drain removal at PODs 1, 3, and 5 if drain fluid amylase (DFA) fell below specific cutoffs based on optimized negative predictive values (NPV) for clinically relevant postoperative pancreatic fistula (CR-POPF). Characteristics of the remaining cohort with drains in situ on POD5 were examined using multivariable analysis (MVA).
Results
Intraoperative FRS would preclude drains from 230 (35.9%) negligible/low-risk cases with a cohort CR-POPF rate of 1.7%. Of the remaining patients, 30.5% would have drains removed on POD1 based on a DFA threshold of 300 IU/L (NPV = 98.4%), demonstrating a 1.6% CR-POPF rate. On POD3, drains could be removed in the residual cohort from 21.1% of patients with DFA ≤ 150 IU/L (NPV = 96.6%), reflecting a 3.4% CR-POPF rate. On POD5, a DFA threshold of 50 IU/L (NPV = 84%) identified 16.3% more patients whose drains could be removed. The remaining cohort (POD5 DFA > 50 IU/L), “enriched” for fistula development and reflecting just 18.4% of the original patients, displays a 61% CR-POPF rate. Among these patients on POD5, a DFA threshold > 2000 IU/L best predicted subsequent CR-POPF (PPV = 89.5%), and MVA revealed a positive association between pancreatic cancer/pancreatitis (OR = 4.37,
p
= 0.022) and longer operations (OR = 3.74,
p
= 0.014) with CR-POPF development.
Conclusion
Early drain removal is a dynamic concept and can be employed throughout the postoperative time course using conditional thresholds to better identify patients at risk for CR-POPF.
Journal Article
The Characterization and Prediction of ISGPF Grade C Fistulas Following Pancreatoduodenectomy
2016
Introduction
International Study Group of Pancreatic Fistula (ISGPF) grade C postoperative pancreatic fistulas (POPF) are the greatest contributor to major morbidity and mortality following pancreatoduodenectomy (PD); however, their infrequent occurrence has hindered deeper analysis. This study sought to develop a predictive algorithm, which could facilitate effective management of this challenging complication.
Methods
Data were accrued from 4301 PDs worldwide. Demographics, postoperative management, and microbiological characteristics of grade C POPFs were evaluated. American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) preoperative and intraoperative variables were compared between grade C POPFs and a 639-case sample of non-grade C POPFs. Risk factors for grade C POPF formation were identified using regression analysis.
Results
Grade C POPFs developed in 79 patients (1.8 %). Deaths (90 days) occurred in 2.0 % (
N
= 88) of the overall series, with 35 % (
N
= 25) occurring in the presence of a grade C POPF. Reoperations occurred 72.2 % of the time. The rates of single- and multi-system organ failure were 28.2 and 39.7 %, respectively. Mortality rates escalated with pulmonary, renal, and neurologic organ failure, but they were unaffected by reoperation(s). The median number of complications incurred was four (IQR: 2–5), and the median duration of hospital stay was 32 (IQR: 21–54) days. Warning signs for impending grade C POPFs most often presented on postoperative day (POD) 6. Adjuvant chemotherapy might have benefited 55.7 % of grade C POPF patients, yet it was delayed in 25.6 % and never delivered in 67.4 % of these patients. Predictive models for grade C POPF occurrence based on preoperative factors alone and preoperative and intraoperative factors yielded areas under the receiver operating characteristic curve of 0.73 and 0.84 (both
P
< 0.000001), respectively.
Conclusion
This global study represents the largest analysis of grade C POPFs following PD. It describes the severe burden that grade C POPFs incur on patients, with high rates of reoperation and infection, while also potentially worsening overall survival by causing death and delay/omission of adjuvant therapy. Additionally, aggressive clinical management for these POPFs did not improve or worsen 90-day mortality. Predictive tools developed through these data may provide value in managing this difficult complication.
Journal Article