Clinical significance of revised microscopic positive resection margin status in ductal adenocarcinoma of pancreatic head

Changing Clinical Meaning of Resection Margin Status According to the Treatment Paradigm and the Potential Role of Perioperative Radiotherapy for Patients with Pancreatic Ductal Adenocarcinoma: An Updated Multicenter Retrospective Cohort Study

BACKGROUND

Surgeons have focused on obtaining microscopically negative margins and developing perioperative treatment strategies for pancreatic head cancer. However, the clinical significance of resection margin and radiotherapy remains unclear, particularly in neoadjuvant chemotherapy (NAC) settings. Therefore, this study aimed to evaluate the prognostic impact of margin status and perioperative radiotherapy.

METHODS

Between 2014 and 2019, the study enrolled 307 patients with pancreatic head cancer who underwent upfront pancreaticoduodenectomy (PD) and 97 patients who underwent NAC followed by PD at three tertiary referral hospitals. The margin status was divided into a three-tier system as follows: R0-wide (tumor-free margin, ≥ 1 mm), R0-narrow (0 mm < margin < 1 mm), and R1 (margin = 0 mm).

RESULTS

In the upfront surgery setting, the groups were arranged in descending order of the 5-year overall survival (OS) rates as follows: R0-wide (39.1%), R0-narrow (25.6%), and R1 (12.5%). In the NAC setting, the groups also could be arranged in descending order of 5-year OS rates as follows: R0-wide (52.2%), R0-narrow (45.5%), and R1 (8.3%). However, the differences in OS between the R0-wide and R0-narrow groups did not reach statistical significance (P = 0.587), in contrast to the upfront surgery setting. In the multivariate analyses, concurrent chemo-radiotherapy after surgery was significantly associated with a decreased risk of locoregional recurrence in both treatment settings.

CONCLUSIONS

Obtaining a wide margin could enhance prognosis in upfront surgery settings, and obtaining only a narrow margin could be appropriate in NAC settings. In addition, adjuvant radiotherapy could be considered, particularly for patients with margin involvement.

Prognostic implications of resection margin status in distal pancreatectomy for pancreatic ductal adenocarcinoma

BACKGROUND

Curative resection is a well known prognostic factor in pancreatectomy. However, definition and clinical significance of resection margin in distal pancreatectomy remains controversial.

METHODS

From 2010 to 2018, 203 patients with pancreatic cancer undergoing distal pancreatectomies were included. Patients were classified into three groups: R0-wide (tumor-free margin ≥1 mm), R0-narrow (0 mm < tumor-free margin <1 mm), and R1 margin (tumor-free margin = 0 mm). We also evaluated the prognostic impact of individual margins (transection, anterior, and posterior).

RESULTS

Patients with an R0-wide margin (36.6 %) exhibited superior 5-year disease free survival rate compared to those with R0-narrow (30.4 %, p = 0.059) or R1 margin (0.1 %, p = 0.014). However, in multivariate analyses, only R1 margin (hazard ratio [95 % confidence interval], 2.02 [1.32-3.12]; p = 0.001), unlike R0-narrow margin (1.17 [0.78-1.77]; p = 0.446), was linked to shorter overall survival compared to R0-wide margin. In multivariate analyses, posterior margin involvement was uniquely identified as a poor prognostic factor (1.83 [1.07-3.13]; p = 0.027).

CONCLUSIONS

The 0 mm rule seems more suitable than the 1 mm rule for predicting prognosis in performing distal pancreatectomy, and especially, achieving microscopically negative posterior margin is crucial.

Implications of portal vein/superior mesenteric vein involvement in pancreatic cancer: A comprehensive correlation from preoperative radiological assessment to resection, pathology, and long-term outcomes. A retrospective cohort study

BACKGROUND

The incidence of portal vein/superior mesenteric vein (PV/SMV) resection during pancreatoduodenectomy is increasing in clinical practice. This study investigated the clinical significance of preoperative PV/SMV assessment and intraoperative resection and their correlation with pathological results and long-term survival outcomes.

METHODS

We analyzed 443 patients undergoing pancreatoduodenectomy at a tertiary center from 2012 to 2017 based on PV/SMV resection. Subgroup analyses were performed based on preoperative PV/SMV involvement, resection, and margin status.

RESULTS

Total of 441 patients were analyzed; 175 had PV/SMV involvement on preoperative radiological assessments and 128 underwent PV/SMV resection. True pathological invasion was observed in 78 patients (60.9%), with 34.3% showing no invasion and negative margins. The positive predictive value for preoperative PV/SMV involvement was 61.7%, with a false-negative value of 28.9%. Overall survival of patients who underwent PV/SMV resection was worse than those who did not (2-year survival rate, 38.1% vs 54.9%, P < 0.001). Patients without PV/SMV resection with an rR1/R1 margin showed no decrease in survival compared to those with PV/SMV resection and R0 margins (54.9% vs 40.3%, P = 0.029). Prognostic factors included hypertension, PV/SMV resection, PV/SMV R2 margin, T stage, N stage, cell differentiation, adjuvant treatment, and recurrence.

CONCLUSION

PV/SMV resection could ensure R0 resection but may lead to unnecessary resection. Careful consideration is essential in determining the need for PV/SMV resection. Poor survival in such patients highlights the need for tailored treatments, including neoadjuvant therapy, for those who are expected to undergo PV/SMV resections.

Neoadjuvant chemotherapy and stereotactic body radiation therapy for borderline resectable pancreas adenocarcinoma: influence of vascular margin status and type of chemotherapy

BACKGROUND

The influence of chemotherapy type and vascular margin status after sequential chemotherapy and stereotactic body radiation therapy (SBRT) for borderline resectable pancreatic cancer (BRPC) is unknown.

METHODS

A retrospective review was performed on BRPC patients treated with chemotherapy and 5-fraction SBRT from 2009 to 2021. Surgical outcomes and SBRT-related toxicity were reported. Clinical outcomes were estimated by Kaplan-Meier with log rank comparisons.

RESULTS

A total of 303 patients received neoadjuvant chemotherapy and SBRT to a median dose of 40 Gy prescribed to the tumor-vessel interface and median dose of 32.4 Gyto 95% of the gross tumor volume. One hundred and sixty-nine patients (56%) were resected and benefited from improved median OS (41.1 vs 15.5 months, P < 0.001). Close/positive vascular margins were not associated with worse OS or FFLRF. Type of neoadjuvant chemotherapy did not influence OS for resected patients, but FOLFIRINOX was associated with improved median OS in unresected patients (18.2 vs 13.1 months, P = 0.001).

CONCLUSION

For BRPC, the effect of a positive or close vascular margin may be mitigated by neoadjuvant therapy. Shorter duration neoadjuvant chemotherapy as well as the optimal biological effective dose of radiotherapy should be prospectively explored.

Necrosis as a strong independent prognostic factor required in the implementation of pathological reporting for pancreatic adenocarcinoma resection specimens

INTRODUCTION

Pancreatic ductal adenocarcinoma (PDAC) is a major public health issue with an incidence/mortality ratio reaching 98 %. Only 15-20 % of patients with PDAC can undergo surgery. Following PDAC surgical resection, 80 % of patients will experience local or metastatic recurrence of this disease. pTNM staging is the gold standard for risk stratification but is not sufficient to recapitulate the prognosis. Several prognostic factors are known to impact survival after surgery when uncovered during pathological examination. However, necrosis has been poorly studied in pancreatic adenocarcinoma.

MATERIALS & METHODS

We retrieved clinical data and reviewed all tumor slides from patients who had a pancreatic surgery between January 2004 and December 2017, in the Hospices Civils de Lyon, to assess the presence of histopathological prognosis factors associated with poor prognosis.

RESULTS

514 patients with complete clinico-pathological description were included. Necrosis was found in 231 PDAC (44.9 %) and had an important impact on overall survival with a double risk of death when present in tumor samples (HR: 1.871, 95 % CI [1.523; 2.299], p < 0.001). When integrated in the multivariate model, necrosis is the only morphological aggressive feature to retain high statistical significance associated with the TNM staging but independently of it. This effect is independent of the preoperative treatment.

CONCLUSIONS

Despites improvement in treatment of PDAC, mortality rates remain relatively stable amongst the last years. There is a desperate need to better stratify patients. Here, we report the strong and prognostic impact of necrosis in surgical PDAC samples and encourage pathologists to report its presence in the future.

"Plane first" approach for laparoscopic radical antegrade modular pancreatosplenectomy

BACKGROUND

Laparoscopic radical antegrade modular pancreatosplenectomy (L-RAMPS) has not been widely performed due to its technical challenging. We introduce a novel approach, named "Plane first" approach, for L-RAMPS in this study.

METHODS

From January 2015 to August 2021, we performed 51 cases of L-RAMPS. Patients were divided into two groups basing on the surgical approach: conventional approach (group 1) and "Plane first" approach (group 2). Data were retrospectively collected in terms of demographic characteristics, intra-operative variables, post-operative variables, and follow-up outcomes.

RESULTS

The age, sex, BMI, and tumor size were comparable between two groups. Two patients in the group 1 required converting to open surgery. The patients in the group 2 required fewer operative time (210.5 ± 65.5 min vs. 252.4 ± 24.7 min, p < 0.01). They also suffered from less blood loss (136.0 ± 100.0 ml vs. 158.8 ± 137.0 ml, p = 0.15). The overall complications for patients in two groups were comparable. In terms of oncological outcomes, posterior margin was positive in two patients (10.5%) in the group 1. One patient (3.1%) in the group 2 had positive pancreatic neck margin. The number of lymph nodes harvested and overall survival between the two groups were comparable.

CONCLUSION

"Plane first" approach RAMPS for patients with pancreatic adenocarcinoma in the left pancreas is safe and feasible, even in patients with PV/SMV involvement.

Prognostic relevance of the revised R status definition in pancreatic cancer: meta-analysis

BACKGROUND

The prognostic impact of margin status is reported with conflicting results after pancreatic cancer resection. While some studies validated an uninvolved resection margin (R0) 1 mm or more of tumour clearance, others have failed to show benefit. This systematic review and meta-analysis aimed to investigate the effects of margin definitions on median overall survival (OS).

METHODS

MEDLINE, Web of Science, and the Cochrane Central Register of Controlled Trials were searched for studies reporting associations between resection margins and OS between 2010 and 2021. Data regarding margin status (R0 circumferential resection margin (CRM) negative (CRM-), R0 CRM positive (CRM+), R0 direct, and R1 and OS were extracted. Hazard ratios (HRs) were pooled with a random-effects model. The risk of bias was evaluated with the Quality in Prognosis Studies (QUIPS) tool.

RESULTS

The full texts of 774 studies were screened. In total, 21 studies compromising 6056 patients were included in the final synthesis. In total, 188 (24 per cent) studies were excluded due to missing margin definitions. The R0 (CRM+) rate was 50 per cent (95 per cent confidence interval (c.i.) 0.40 to 0.61) and the R0 (CRM-) rate was 38 per cent (95 per cent c.i. 0.29 to 0.47). R0 (CRM-) resection was independently associated with improved OS compared to combined R1 and R0 (CRM+; HR 1.36, 95 per cent c.i. 1.23 to 1.56).

CONCLUSION

The revised R status was confirmed as an independent prognosticator compared to combined R0 (CRM+) and R1. The limited number of studies, non-standardized pathology protocols, and the varying number of margins assessed hamper comparability.

Impact of Neoadjuvant Therapy on Survival Following Margin-Positive Resection for Pancreatic Cancer

INTRODUCTION

A positive microscopic margin (R1) following resection of pancreatic ductal adenocarcinoma (PDAC) can occur in up to 80% of patients and is associated with reduced survival and increased recurrence. Our aim was to characterize the impact of neoadjuvant therapy (NAT) on survival and recurrence in patients with PDAC following an R1 resection.

METHODS

A retrospective analysis of patients with PDAC who underwent pancreatectomy from 2008 to 2017 was performed. Patients were staged according to the American Joint Committee on Cancer 8th edition and stratified based on resection margin (R0 vs. R1) and treatment sequence (NAT vs. surgery first [SF]). Conditional survival analysis was performed using Cox regression and inverse probability weighted estimates.

RESULTS

Among 580 patients, 59% received NAT and 41% underwent SF. On final pathology, the NAT cohort had smaller tumors and less lymph node (LN) positivity (p < 0.05). NAT was not associated with an R1 resection (50%, p = 0.653). Compared with the R1 cohort, the R0 cohort had a higher median overall survival (OS; 39.6 vs. 22.8 months; hazard ratio [HR] 1.6, p < 0.001) and disease-free survival (DFS; 19 vs. 13 months; HR 1.35, p = 0.004). After risk adjustment, NAT was not associated with OS, regardless of margin status (R0, 95% confidence interval [CI] (-)7.31-27.07, p = 0.26; or R1, 95% CI (-)36.99-15.25, p = 0.42). However, NAT was associated with improved DFS in the R1 cohort (95% CI 1.79-11.91, p = 0.008) but not in the R0 cohort (95% CI (-)11.22-10.54, p = 0.95).

CONCLUSION

An R0 resection remains an important determinant of overall and disease-free survival, even when NAT is administered. For patients with an R1 resection, receipt of NAT may prolong DFS.

R Status is a Relevant Prognostic Factor for Recurrence and Survival After Pancreatic Head Resection for Ductal Adenocarcinoma

BACKGROUND

The prognostic role of resection margins in pancreatic ductal adenocarcinoma (PDAC) is debated. This study aimed to investigate the impact that global and individual resection margin status after pancreatic head resection for PDAC has on disease-free survival (DFS) and disease-specific survival (DSS).

METHODS

Surgical specimens of pancreaticoduodenectomy/total pancreatectomy performed for PDAC were examined with a standardized protocol. Surgical margin status (biliary, pancreatic neck, duodenal, anterior and posterior pancreatic, superior mesenteric vein groove and superior mesenteric artery margins) was classified as the presence of malignant cells (1) directly at the inked surface (R1 direct), (2) within less than 1 mm (R1 ≤ 1 mm), or (3) with a distance greater than 1 mm (R0). Patients with a positive neck margin at the final histology were excluded from the study.

RESULTS

Of the 362 patients included in the study, 179 patients (49.4 %) had an R0 resection, 123 patients (34 %) had an R1 ≤ 1 mm resection, and 60 patients (16.6 %) had an R1 direct resection. The independent predictors of DFS were R1 direct resection (hazard ratio [HR], 1.49), R1 ≤ 1 mm resection (HR, 1.38), involvement of one margin (HR, 1.36), and involvement of two margins or more (HR, 1.55). When surgical margins were analyzed separately, only R1 ≤ 1 mm superior mesenteric vein margin (HR, 1.58) and R1 direct posterior margin (HR, 1.69) were independently associated with DFS.

CONCLUSIONS

Positive R status is an independent predictor of DFS (R1 direct and R1 ≤ 1 mm definitions) and of DSS (R1 direct). The presence of multiple positive margins is a risk factor for cancer recurrence and poor survival. Different surgical margins could have different prognostic roles.

Detailed Analysis of Margin Positivity and the Site of Local Recurrence After Pancreaticoduodenectomy

BACKGROUND

The association between a positive surgical margin and local recurrence after resection of pancreatic adenocarcinoma (PDAC) has been reported. Assessment of the location of the a positive margin and the specific site of local recurrence has not been well described.

METHODS

A prospectively maintained database was queried for patients who underwent R0/R1 pancreaticoduodenectomy for PDAC between 2000 and 2015. The pancreatic, posterior, gastric/duodenal, anterior peritoneal, and bile duct margins were routinely assessed. Postoperative imaging was reviewed for the site of first recurrence, and local recurrence was defined as recurrence located in the remnant pancreas, surgical bed, or retroperitoneal site outside the surgical bed.

RESULTS

During the study period, 891 patients underwent pancreaticoduodenectomy, and 390 patients had an initial local recurrence with or without distant metastases. The 5-year cumulative incidence of local recurrence by site included the remnant pancreas (4%; 95% confidence interval [CI], 3-5%), the surgical bed (35%; 95% CI, 32-39%), and other regional retroperitoneal site (4%; 95% CI, 3-6%). In the univariate analysis, positive posterior margin (hazard ratio [HR], 1.50; 95% CI, 1.17-1.91; p = 0.001) and positive lymph nodes (HR, 1.36; 95% CI, 1.06-1.75; p = 0.017) were associated with surgical bed recurrence, and in the multivariate analysis, positive posterior margin remained significant (HR, 1.40; 95% CI, 1.09-1.81; p = 0.009). An isolated local recurrence was found in 197 patients, and a positive posterior margin was associated with surgical bed recurrence in this subgroup (HR, 1.51; 95% CI, 1.08-2.10; p = 0.016).

CONCLUSION

In this study, the primary association between site of margin positivity and site of local recurrence was between the posterior margin and surgical bed recurrence. Given this association and the limited ability to modify this margin intraoperatively, preoperative assessment should be emphasized.

Clinical outcomes of pancreaticoduodenectomy for pancreatic ductal adenocarcinoma depending on preservation or resection of pylorus

Backgrounds/Aims

The comparative effectiveness of pylorus-resecting pancreaticoduodenectomy (PRPD) and pylorus-preserving pancreaticoduodenectomy (PPPD) in pancreatic head cancer is still disputed. The aim of this study was to analyze the data obtained from a large, single center with PPPD compared with PRPD in terms of postoperative outcomes, including blood glucose levels and survival in patients with pancreatic head cancer.

Methods

Between January 2007 and December 2016, a total of 556 patients with pancreatic head cancer underwent either PPPD or PRPD. We analyzed the clinicopathologic data to assess short- and long-term outcomes retrospectively.

Results

For underlying disease, patients with DM in PPPD were fewer than in PRPD (33.0% vs. 46.2%, p=0.002). The median value of CA19-9 was significantly higher in PRPD than in PPPD (129.36 vs. 86.47, p=0.037). The incidence of Clavien-Dindo grade III to V major complications in PPPD was significantly higher than in PRPD (20.4% vs. 13.4%, p=0.032). Resection of pylorus was shown to reduce complications in univariate and multivariate analyses (p=0.032 and = 0.021, respectively). The 5-year survival rates were 27.6% in the PPPD group and 22.4% in the PRPD group (p=0.015).

Conclusions

The results of PPPD and PRPD showed no significant differences from those reported conventionally in previous studies. Although further well-designed studies are needed, it is more important to select the range of surgical resection for the patient’s disease regardless of resection of pylorus.

Three Thousand Consecutive Pancreaticoduodenectomies in a Tertiary Cancer Center: A Retrospective Observational Study

(1) Aim: To evaluate clinicopathological features and postoperative outcomes including survival in patients who underwent pancreaticoduodenectomy (PD) for periampullary diseases. (2) Methods: We retrospectively reviewed 3078 cases of PD performed in our center for 25 years. Periampullary diseases were divided into benign and malignancy groups. All cases were also classified by location. The time of 25 years was divided to different periods (5 years per period) to compare outcomes. Overall survival was compared between subdivided periods. (3) Results: Hospitalization became significantly shorter from 28.0 days in the 1st period to 13.8 days in the 5th period. Overall complication rate was significantly increased since the 3rd period. The rate without postoperative pancreatic fistula (POPF) was high at 98.7% in the 1st period. This might be because drain amylase on the 3rd day after PD was not routinely checked in the past. Thus, POPF was not detected. In survival analysis of adenocarcinoma of pancreas, bile duct, and ampulla, overall survival was found to be improved significantly in recent years. (4) Conclusions: Our study revealed that outcomes were improved with increasing number of PDs performed. Although POPF and overall complications showed increases more recently, those were detected and managed, resulting in shorter hospitalization and improved outcomes.