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

To Revise or Not Revise? Isolated Margin Positivity in Localized Pancreatic Ductal Adenocarcinoma

BACKGROUND

The study determined the proportion of patients with pancreatic adenocarcinoma (PDAC) who had margin-positive disease and no other adverse pathologic findings (APF) using institutional and administrative datasets.

METHODS

Patients with clinical stage I or II PDAC in the National Cancer Database (NCDB 2010-2020) and those who underwent pancreatectomy at the authors' institution (2010-2021) were identified. Isolated margin positivity (IMP) was defined as a positive surgical margin with no APF (negative nodes, no lymphovascular/perineural invasion).

RESULTS

The study included 225 patients from the authors' institution and 23,598 patients from the NCDB. The margin-positive rates were 21.8% and 20.3%, and the IMP rates were 0.4% and 0.5%, respectively. In the institutional cohort, 68.4% of the patients had recurrence, and most of the patients (65.6%) had distant recurrences. The median recurrence-free survival (RFS) was 63.3 months for no APF, not reached for IMP, 14.8 months for negative margins & 1 APF, 20.3 months for positive margins & 2 APFs, and 12.9 months with all APF positive. The patients in the NCDB with IMP had a lower median OS than the patients with no APF (20.5 vs 390 months), but a higher median OS than those with margin positivity plus 1 APF (20.5 vs 18.0 months) or all those with APF positivity (20.5 vs 15.4 months). Based on institutional rates of IMP, any margin positivity, neck margin positivity (NMP), and no APF, the fraction of patients who might benefit from neck margin revision was 1 in 100,000, and those likely to benefit from any margin revision was 1 in 18,500. In the NCDB, those estimated to derive potential benefit from margin revision was 1 in 25,000.

CONCLUSIONS

Isolated margin positivity in resected PDAC is rare, and most patients experience distant recurrence. Revision of IMP appears unlikely to confer benefit to most patients.

Circulating tumor cells in pancreatic cancer: The prognostic impact in surgical patients

Pancreatic cancer is associated with a poor prognosis, even in the early stages, mainly due to metastatic progression. New diagnostic techniques that predict unfavorable outcomes are needed in order to improve treatment strategies. Circulating tumor cells (CTCs) are showing promising results as a predictive biomarker for various tumors. In this editorial we comment on the article by Zhang et al, who published the first systematic review and meta-analysis evaluating the prognostic value of CTCs as biomarkers in early-stage pancreatic cancer patients undergoing surgery. CTCs were detected in peripheral or central venous system blood, before or during surgery. Positive CTCs showed a correlation with decreased overall survival and decreased relapse-free, disease-free and progression-free survival in this meta-analysis. However, the heterogeneity was significant. The authors suggest that this result was related to the separation methods used between studies, but other differences such as the margin status or the neoadjuvant and adjuvant treatments used are also important to consider. CTCs may be a potential prognostic biomarker in pancreatic cancer patients, but it is necessary to compare and standardize the platforms used to isolate CTCs, to compare different biomarkers from liquid biopsy and to determine the impact on prognosis when therapeutic changes are made based on CTCs levels.

Undifferentiated sarcomatoid carcinoma of the pancreas-a single-institution experience with 23 cases

BACKGROUND

The clinical course and surgical outcomes of undifferentiated sarcomatoid carcinoma of the pancreas (USCP) remain poorly characterized owing to its rarity. This study aimed to describe the histology, clinicopathologic features, perioperative outcomes, and overall survival (OS) of 23 resected USCP patients.

METHODS

We retrospectively described the histology, clinicopathologic features, perioperative outcomes and OS of patients who underwent pancreatectomy with a final diagnosis of USCP in a single institution.

RESULTS

A total of 23 patients were included in this study. Twelve patients were male, the median age at diagnosis was 61.5 ± 13.0 years (range: 35-89). Patients with USCP had no specific symptoms and characteristic imaging findings. The R0 resection was achieved in 21 cases. The En bloc resection and reconstruction of mesenteric-portal axis was undertaken in 9 patients. There were no deaths attributed to perioperative complications in this study. The intraoperative tumor-draining lymph nodes (TDLNs) dissection was undergone in 14 patients. The 1-, 3- and 5-year survival rates were 43.5%, 4.8% and 4.8% in the whole study, the median survival was 9.0 months. Only 1 patient had survived more than 5 years and was still alive at last follow-up. The presence of distant metastasis (p = 0.004) and the presence of pathologically confirmed mesenteric-portal axis invasion (p = 0.007) was independently associated with poor OS.

CONCLUSIONS

USCP was a rare subgroup of pancreatic malignancies with a bleak prognosis. To make a diagnose of USCP by imaging was quite difficult because of the absence of specific manifestations. Accurate diagnosis depended on pathological biopsy, and the IHC profile of USCP was mainly characterized by co-expression of epithelial and mesenchymal markers. A large proportion of patients have an early demise, especially for patients with distant metastasis and pathologically confirmed mesenteric-portal axis invasion. Long-term survival after radical resection of USCPs remains rare.

Prognostic value of margin clearance in total and distal pancreatectomy specimens with pancreatic ductal adenocarcinoma in a Danish population-based nationwide study

BACKGROUND

The prognostic role of resection margin status following total (TP) and distal (DP) pancreatectomy for pancreatic ductal adenocarcinoma (PDAC) is insufficiently evaluated. In Denmark, pancreatic surgery, including the postoperative pathological examination of the resection specimens, is confined to four centres, all reporting to the Danish Pancreatic Cancer Database (DPCD). In this Danish population-based nationwide study on TP and DP for PDAC from 2015-2019, based on data from DPCD, we evaluated whether there is a prognostically relevant minimum margin clearance definition and whether certain margins hold independent prognostic information.

METHODS

Clinical and pathological data were retrieved from DPCD and supplemented by review of pathology reports and re-microscopy, if needed. One of the study pathologists performed all re-microscopy. The prognostic significance of margin status was evaluated by dichotomisation of the TP cohort (n = 101) and the DP cohort (n = 90) into involved and uninvolved groups, using different clearance definitions (0.5 - ≥3.0 mm).

RESULTS

Following TP, direct involvement of the superior mesenteric artery (SMA) margin had independent prognostic value. When using a clearance definition of ≥ 0.5 or ≥ 1.5 mm for SMA, median survival for R0 versus R1 was 19 (95% CI 14-26) versus 10 (95% CI 5-20) months (p = 0.010), and 21 (95% CI 15-30) versus 10 (95% CI 8-19) months (p = 0.011), respectively. Overall margin status was not of significant prognostic importance following neither DP nor TP.

CONCLUSION

In this Danish population-based nationwide study, SMA margin involvement was a significant isolated prognostic factor following TP, whereas combined assessment of all circumferential margins did not hold statistically significant prognostic information. Following DP, resection margin status did not affect survival.

The Revised R Status is an Independent Predictor of Postresection Survival in Pancreatic Cancer After Neoadjuvant Treatment

OBJECTIVE

To investigate the oncological outcomes of patients with pancreatic ductal adenocarcinoma (PDAC) who had an R 0 or R 1 resection based on the revised R status (1 mm) after neoadjuvant therapy (NAT).

BACKGROUND

The revised R status is an independent prognostic factor in upfront-resected PDAC; however, the significance of 1 mm margin clearance after NAT remains controversial.

METHODS

Patients undergoing pancreatectomy after NAT for PDAC were identified from 2 prospectively maintained databases. Clinicopathological and survival data were analyzed. The primary outcomes were overall survival (OS), recurrence-free survival (RFS), and pattern of recurrence in association with R 0 >1 mm and R 1 ≤1 mm resections.

RESULTS

Three hundred fifty-seven patients with PDAC were included after NAT and subsequent pancreatic resection. Two hundred eight patients (58.3%) received FOLFIRINOX, 41 patients (11.5%) received gemcitabine-based regimens, and 299 individuals (83.8%) received additional radiotherapy. R 0 resections were achieved in 272 patients (76.2%) and 85 patients (23.8%) had R 1 resections. Median OS after R 0 was 41.0 months, compared with 20.6 months after R 1 resection ( P = 0.002), and even longer after additional adjuvant chemotherapy ( R 0 44.8 vs R1 20.1 months; P = 0.0032). Median RFS in the R 0 subgroup was 17.5 months versus 9.4 months in the R 1 subgroup ( P < 0.0001). R status was confirmed as an independent predictor for OS ( R 1 hazard ratio: 1.56, 95% CI: 1.07-2.26) and RFS ( R 1 hazard ratio: 1.52; 95% CI: 1.14-2.0). In addition, R 1 resections were significantly associated with local but not distant recurrence ( P < 0.0005).

CONCLUSIONS

The revised R status is an independent predictor of postresection survival and local recurrence in PDAC after NAT. Achieving R 0 resection with a margin of at least 1 mm should be a primary goal in the surgical treatment of PDAC after NAT.

Perioperative NALIRIFOX in patients with resectable pancreatic ductal adenocarcinoma: The open-label, multicenter, phase II nITRO trial

BACKGROUND

Upfront surgery followed by postoperative treatment is a commonly adopted treatment for resectable pancreatic ductal adenocarcinoma (rPDAC). However, the risk of positive surgical margins, the poor recovery that often impairs postoperative treatments, and the risk of recurrence might limit the outcome of this strategy. This study evaluated the safety and the activity of liposomal irinotecan 50 mg/m2 + 5-fluorouracil 2400 mg/m2 + leucovorin 400 mg/m2 + oxaliplatin 60 mg/m2 (NALIRIFOX) in the perioperative treatment of patients with rPDAC.

METHODS

Eligible patients had a rPDAC with < 180° interface with major veins' wall. Patients received 3 cycles before and 3 cycles after resection with NALIRIFOX, days 1 and 15 of a 28-day cycle. The primary endpoint was the proportion of patients undergoing an R0 resection.

RESULTS

107 patients began preoperative treatment. Nine patients discontinued the treatment because of related or unrelated adverse events. Disease-control rate was 92.9%. 87 patients underwent surgical exploration, 11 had intraoperative evidence of metastatic disease, and 1 died for surgical complications. R0 resection rate was 65.3%. 49 patients completed the three postoperative cycles. The most common grade ≥ 3 adverse events were diarrhea and neutropenia. Median overall survival (OS) of ITT patients was 32.3 months (95% CI 27.8-44.3). Median disease-free and OS from surgery of resected patients were 19.3 (95% CI 12.6-34.1) and 40.3 months (95% CI 29-NA), respectively.

CONCLUSION

Perioperative NALIRIFOX was manageable and active, and deserves further investigation in randomized trials comparing it with standard upfront surgery followed by adjuvant therapy.

Prognostic impact of resection margin status on survival after neoadjuvant treatment for pancreatic cancer: systematic review and meta-analysis

BACKGROUND

A greater than 1 mm tumour-free resection margin (R0 >1 mm) is a prognostic factor in upfront-resected pancreatic ductal adenocarcinoma. After neoadjuvant treatment (NAT); however, the prognostic impact of resection margin (R) status remains controversial.

METHODS

Randomised and non-randomised studies assessing the association of R status and survival in resected pancreatic ductal adenocarcinoma after NAT were sought by systematic searches of MEDLINE, Web of Science and CENTRAL. Hazard ratios (HR) and their corresponding 95% CI were collected to generate log HR using the inverse-variance method. Random-effects meta-analyses were performed and the results presented as weighted HR. Sensitivity and meta-regression analyses were conducted to account for different surgical procedures and varying length of follow-up, respectively.

RESULTS

Twenty-two studies with a total of 4929 patients were included. Based on univariable data, R0 greater than 1 mm was significantly associated with prolonged overall survival (OS) (HR 1.76, 95% CI 1.57-1.97; P<0.00001) and disease-free survival (DFS) (HR 1.66, 95% CI 1.39-1.97; P<0.00001). Using adjusted data, R0 greater than 1 mm was significantly associated with prolonged OS (HR 1.65, 95% CI 1.39-1.97; P<0.00001) and DFS (HR 1.76, 95% CI 1.30-2.39; P=0.0003). Results for R1 direct were comparable in the entire cohort; however, no prognostic impact was detected in sensitivity analysis including only partial pancreatoduodenectomies.

CONCLUSION

After NAT, a tumour-free margin greater than 1 mm is independently associated with improved OS as well as DFS in patients undergoing surgical resection for pancreatic cancer.

Current clinical practice in the management of Brazilian patients with potentially resectable pancreatic ductal adenocarcinoma (PDAC)

BACKGROUND AND OBJECTIVES

We aimed to describe the routine clinical practice of physicians involved in the treatment of patients with localized pancreatic ductal adenocarcinoma (PDAC) in Brazil.

METHODS

Physicians were invited through email and text messages to participate in an electronic survey sponsored by the Brazilian Gastrointestinal Tumor Group (GTG) and the Brazilian Society of Surgical Oncology (SBCO). We evaluated the relationship between variable categories numerically with false discovery rate-adjusted Fisher's exact test p values and graphically with Multiple Correspondence Analysis.

RESULTS

Overall, 255 physicians answered the survey. Most (52.5%) were medical oncologists, treated patients predominantly in the private setting (71.0%), and had access to multidisciplinary tumor boards (MTDTB; 76.1%). Medical oncologists were more likely to describe neoadjuvant therapy as beneficial in the resectable setting and surgeons in the borderline resectable setting. Most physicians would use information on risk factors for early recurrence, frailty, and type of surgery to decide treatment strategy. Doctors working predominantly in public institutions were less likely to have access to MTDTB and to consider FOLFIRINOX the most adequate regimen in the neoadjuvant setting.

CONCLUSIONS

Considerable differences exist in the management of localized PDAC, some of them possibly explained by the medical specialty, but also by the funding source of health care.

A more radical perspective on surgical approach and outcomes in pancreatic cancer-a narrative review

Background and Objective

Pancreatic adenocarcinoma remains a dismal disease and is expected to become an even greater burden in the near future. This review focuses on the different surgical aspects for pancreaticoduodenectomy (PD), distal and total pancreatectomy (TP), incorporating lessons from both the western and eastern visions in treating pancreatic cancer.

Methods

We conducted an extensive literature review through PubMed, prioritizing papers published in the last 5 years, but older emblematic papers were also included. We included articles that explored the treatment of pancreatic adenocarcinoma, with focus on the surgical aspect and strategies to improve outcomes. References of selected articles were also reviewed to identify any missed studies. Only papers in English were included.

Key Content and Findings

As evidence continues to build, it is clear that both systemic and surgical therapies have a fundamental and complementary role. State of art surgical treatment encompasses complete mesopancreas excision for radical lymphadenectomy. Preoperative planning of dissection planes, extensive knowledge of vascular anatomic variations, oncological principles and expertise for vascular resections are mandatory to perform a more radical operation, in pursuit of improved outcomes.

Conclusions

Based on current data, patient selection remains key and a more radical surgical approach brings more accomplishing results bringing as to believe that more is better.

Impact of para aortic lymph node removal on survival following resection for pancreatic adenocarcinoma

INTRODUCTION

For PDAC patients undergoing resection, it remains unclear whether metastases to the paraaortic lymph nodes (PALN+) have any prognostic significance and whether metastases should lead to the operation not being carried out. Our hypothesis is that PALN + status would be associated with short overall survival (OS) compared with PALN-, but longer OS compared with patients undergoing surgical exploration only (EXP).

METHODS

Patients with registered PALN removal from the nationwide Danish Pancreatic Cancer Database (DPCD) from May 1st 2011 to December 31st 2020 were assessed. A cohort of PDAC patients who only had explorative laparotomy due to non-resectable tumors were also included (EXP group). Survival analysis between groups were performed with cox-regression in a multivariate approach including relevant confounders.

RESULTS

A total of 1758 patients were assessed, including 424 (24.1%) patients who only underwent explorative surgery leaving 1334 (75.8%) patients for further assessment. Of these 158 patients (11.8%) had selective PALN removal, of whom 19 patients (12.0%) had PALN+. Survival analyses indicated that explorative surgery was associated with significantly shorter OS compared with resection and PALN + status (Hazard Ratio 2.36, p < 0.001). No difference between PALN + and PALN- status could be demonstrated in resected patients after controlling for confounders.

CONCLUSION

PALN + status in patients undergoing resection offer improved survival compared with EXP. PALN + should not be seen as a contraindication for curative intended resection.

Interobserver Variability and Accuracy of Preoperative CT and MRI in Pancreatic Ductal Adenocarcinoma Size Estimation: A Retrospective Cohort Study

Purpose: To assess interobserver variability and accuracy of preoperative computed tomography (CT) and magnetic resonance imaging (MRI) in pancreatic ductal adenocarcinoma (PDAC) size estimation using surgical specimens as standard of reference. Methods: Patients with PDAC who underwent preoperative CT and MRI examinations before surgery were included. PDAC largest axial dimension was measured by 2 readers on 8 MRI sequence and 2 CT imaging phases (pancreatic parenchymal and portal venous). Measurements were compared to actual tumour size at pathologic examination. Interobserver variability was assessed using intraclass correlation coefficients (ICC) and Bland-Altman plots. Differences in tumour size (Δdiameter) between imaging and actual tumour size were searched using Wilcoxon rank sum test. Results: Twenty-nine patients (16 men; median age, 70 years) with surgically resected PDAC were included. Interobserver reproducibility was good to excellent for all MRI sequences and the 2 CT imaging phases with ICCs between .862 (95%CI: .692-.942) for fat-saturated in-phase T1-weighted sequence and .955 (95%CI: .898-.980) for portal venous phase CT images. Best accuracy in PDAC size measurement was obtained with pancreatic parenchymal phase CT images with median Δdiameters of -2 mm for both readers, mean relative differences of -9% and -6% and no significant differences with dimensions at histopathological analysis (P = .051). All MRI sequences led to significant underestimation of PDAC size (median Δdiameters, -6 to -1 mm; mean relative differences, -21% to -11%). Conclusions: Most accurate measurement of PDAC size is obtained with CT images obtained during the pancreatic parenchymal phase. MRI results in significant underestimation of PDAC size.

Intraoperative Imaging in Hepatopancreatobiliary Surgery

Hepatopancreatobiliary surgery belongs to one of the most complex fields of general surgery. An intricate and vital anatomy is accompanied by difficult distinctions of tumors from fibrosis and inflammation; the identification of precise tumor margins; or small, even disappearing, lesions on currently available imaging. The routine implementation of ultrasound use shifted the possibilities in the operating room, yet more precision is necessary to achieve negative resection margins. Modalities utilizing fluorescent-compatible dyes have proven their role in hepatopancreatobiliary surgery, although this is not yet a routine practice, as there are many limitations. Modalities, such as photoacoustic imaging or 3D holograms, are emerging but are mostly limited to preclinical settings. There is a need to identify and develop an ideal contrast agent capable of differentiating between malignant and benign tissue and to report on the prognostic benefits of implemented intraoperative imaging in order to navigate clinical translation. This review focuses on existing and developing imaging modalities for intraoperative use, tailored to the needs of hepatopancreatobiliary cancers. We will also cover the application of these imaging techniques to theranostics to achieve combined diagnostic and therapeutic potential.

Resection margin status at the portomesenteric axis may not determine oncologic outcome after pancreaticoduodenectomy for lymph node-positive pancreatic ductal adenocarcinoma

BACKGROUND

Lymph node and resection margin status are associated with oncologic outcomes after pancreaticoduodenectomy for pancreatic ductal adenocarcinoma. However, surgical radicality at the portomesenteric axis in case of suspected infiltration remains controversial.

METHODS

Clinicopathological data of patients who underwent a partial or total pancreaticoduodenectomy for PDAC between 2012 to 2019 in 2 major hepato-pancreato-biliary centers in Germany and Switzerland were assessed. We evaluated the impact of positive resection margins at the vascular, parenchymal, and retropancreatic surfaces on overall survival in patients with and without lymph node involvement. Margin-positive vascular resection included both patients with positive margins at the vascular groove and the resected venous wall.

RESULTS

During the study period, 217 patients underwent partial/total pancreaticoduodenectomy for pancreatic ductal adenocarcinoma. After excluding 7 patients suffering postoperative complications resulting in mortality within 90 days after surgery (3%), 169 patients had lymph node involvement (80%). In the entire study cohort, margin-positive resection (33%) was significantly associated with worse overall survival (3-year overall survival: margin-positive resection: 27% vs margin-negative resection: 43%, P = .014). Among patients with positive lymph nodes, margin-positive vascular resection (n = 48, 28%) was not significantly associated with impaired overall survival (3-year overall survival: margin-positive vascular resection: 28% vs margin-negative vascular resection: 36%, P = .065). On the contrary, margin-positive parenchymal resection (n = 7, 4%) (3-year overall survival: margin-positive parenchymal resection: 0% vs margin-negative parenchymal resection: 35%, P < .0001) and margin-positive retropancreatic resection (n = 21, 12%) (3-year overall survival: margin-positive retropancreatic resection: 6% vs margin-negative retropancreatic resection: 39%, P < .0001) significantly diminished overall survival in univariate and multivariate analysis in all patients. Among patients without lymph node involvement (n = 41, 20%), there were no margin-positive parenchymal or margin-positive retropancreatic resections. In contrast, only 5 patients had margin-positive vascular resection (12%), with overall survival compared to those with margin-negative vascular resection.

CONCLUSIONS

In patients with pancreatic ductal adenocarcinoma and lymph nodal positivity, resection status at the parenchymal and retropancreatic surface but probably not at the portal and/or superior mesenteric vein is a determinant of survival. Therefore, margin-negative resection should be pursued during pancreaticoduodenectomy. However, radical venous resection and/or reconstruction for suspected tumor infiltration may not be necessary for patients with intraoperatively detected lymph node metastases.

The Impact of Involved Resection Margin on Recurrence and Survival After Pancreaticoduodenectomy for Periampullary Carcinoma, with Emphasis on Pancreatic Head Carcinoma

BACKGROUND

The supposed adverse effect of involved resection margin during pancreaticoduodenectomy (PD) for periampullary carcinoma or pancreatic head carcinoma (CaP) on long-term oncological outcomes is still inconclusive.

METHODS

This is a retrospective study on periampullary carcinoma undergoing PD. Patients with R0 (margin clear) resection were compared to patients with R1 (microscopically directly involved margin) resection. Patients with gross involved margin (R2 resection) were excluded. Long-term oncological outcomes measured included incidence and site of recurrent disease, overall survival (OS) and disease-free survival (DFS). A subgroup analysis was made on patients with CaP.

RESULTS

Between January 2003 and December 2019, 203 PD were identified for present study. The incidence of R1 resection was common (12% in periampullary carcinoma and 20% in CaP). In periampullary carcinoma, R1 resection had greater proportion of CaP, lesser proportion of carcinoma of ampulla (CaA), more perineural invasion, more lymph node (LN) metastasis. R1 group had a shorter OS and DFS, but no difference in the incidence and site of recurrent disease. In the subgroup of CaP (91 patients), R1 group did not differ from R0 group except for more LN metastasis. There was no difference in incidence and site of recurrent disease, OS and DFS. On multivariable analysis, R1 resection was not an independent factor for OS and DFS for periampullary carcinoma or for CaP only.

CONCLUSION

Involved resection margin was not uncommon. It was not associated with higher incidence of recurrent disease including local recurrence, and was not an independent prognosticator for OS and DFS.

Long-Term Outcomes of Venous Resections in Pancreatic Ductal Adenocarcinoma Patients: A Nationwide Cohort Study

To investigate whether pancreatic resections (PR) for pancreatic ductal adenocarcinoma (PDAC) is associated with worse survival when resection of the superior mesenteric vein/portal vein (SMV/PV) is required.

Background

PR for PDAC with resection of the superior mesenteric vein/portal vein (SMV/PV, PR+V resection) may be associated with inferior overall survival (OS) compared with PR without the need for SMV/PV resection (PR-V). We hypothesized that PR+V results in lower OS compared with PR-V.

Method

Retrospective study using data from the nationwide Danish Pancreatic Cancer Database from 2011 to 2020. Data on patients who underwent PR for PDAC were extracted. A group of PR patients found nonresectable on exploratory laparotomy (EXP) was also included. OS was assessed using Kaplan-Meier and Cox proportional hazards models adjusting for confounders (age, sex, R-resection level, chemotherapy, comorbidities, histology T and N classification, procedure subtype as well as tumor distance to the SMV/PV).

Results

Overall, 2403 patients were identified. Six hundred two underwent exploration only (EXP group), whereas 412 underwent pancreatic resection with (PR+V group) and 1389 (PR-V) without SMV/PV resection. Five-year OS for the PR+V group was lower (20% vs 30%) compared with PR-V, although multivariate Cox proportional hazards modeling could not associate PR+V status with OS (Hazard ratio 1.11, P = 0.408).

Conclusion

When correcting for confounders, PR+V was not associated with lower OS compared with PR-V.

Prognostic Value of Sarcopenia and Myosteatosis in Patients with Resectable Pancreatic Ductal Adenocarcinoma

OBJECTIVE

The clinical relevance of myosteatosis has not been well evaluated in patients with pancreatic ductal adenocarcinoma (PDAC), although sarcopenia has been extensively researched. Therefore, we evaluated the prognostic value of muscle quality, including myosteatosis, in patients with resectable PDAC treated surgically.

MATERIALS AND METHODS

We retrospectively evaluated 347 patients with resectable PDAC who underwent curative surgery (mean age ± standard deviation, 63.6 ± 9.6 years; 202 male). Automatic muscle segmentation was performed on preoperative computed tomography (CT) images using an artificial intelligence program. A single axial image of the portal phase at the inferior endplate level of the L3 vertebra was used for analysis in each patient. Sarcopenia was evaluated using the skeletal muscle index, calculated as the skeletal muscle area (SMA) divided by the height squared. The mean SMA attenuation was used to evaluate myosteatosis. Diagnostic cutoff values for sarcopenia and myosteatosis were devised using the Contal and O'Quigley methods, and patients were classified according to normal (nMT), sarcopenic (sMT), myosteatotic (mMT), or combined (cMT) muscle quality types. Multivariable Cox regression analyses were conducted to assess the effects of muscle type on the overall survival (OS) and recurrence-free survival (RFS) after surgery.

RESULTS

Eighty-four (24.2%), 73 (21.0%), 75 (21.6%), and 115 (33.1%) patients were classified as having nMT, sMT, mMT, and cMT, respectively. Compared to nMT, mMT and cMT were significantly associated with poorer OS, with hazard ratios (HRs) of 1.49 (95% confidence interval, 1.00-2.22) and 1.68 (1.16-2.43), respectively, while sMT was not (HR of 1.40 [0.94-2.10]). Only mMT was significantly associated with poorer RFS, with an HR of 1.59 (1.07-2.35), while sMT and cMT were not.

CONCLUSION

Myosteatosis was associated with poor OS and RFS in patients with resectable PDAC who underwent curative surgery.

Prognostic Impact of Resection Margin Status on Distal Pancreatectomy for Ductal Adenocarcinoma

Pancreatic cancer is associated with a poor prognosis. While surgical resection is the only treatment option with curative intent, most patients die of locoregional and/or distant recurrence. The prognostic impact of the resection margin status has received much attention. However, the evidence is almost exclusively related to pancreatoduodenectomies, while corresponding data for distal pancreatectomy specimens are limited. The key data, such as the rate of microscopic margin involvement (“R1”), the site of margin involvement, and the impact of R1 on patient outcome, are divergent between studies and do not currently allow any general conclusions. The main reasons for the variability in the published data are the small size of the study cohorts and their heterogeneity, as well as the marked divergence in pathology examination practices. The latter is a consequence of the lack of concrete guidance, both for grossing and microscopic examination. The increasing administration of neoadjuvant chemo(radio)therapy introduces a further factor of uncertainty as the conventional definition of a tumour-free margin (“R0”) based on 1 mm clearance is inadequate for these specimens. This review discusses the published data regarding the prognostic impact of margin status in distal pancreatectomy specimens along with the challenges and uncertainties that are related to the assessment of the margins.

Imaging of Pancreatic Ductal Adenocarcinoma: An Update on Recent Advances

Pancreatic ductal carcinoma (PDAC) is one of the leading causes of cancer-related death worldwide. Computed tomography (CT) remains the primary imaging modality for diagnosis of PDAC. However, CT has limitations for early pancreatic tumor detection and tumor characterization so that it is currently challenged by magnetic resonance imaging. More recently, a particular attention has been given to radiomics for the characterization of pancreatic lesions using extraction and analysis of quantitative imaging features. In addition, radiomics has currently many applications that are developed in conjunction with artificial intelligence (AI) with the aim of better characterizing pancreatic lesions and providing a more precise assessment of tumor burden. This review article sums up recent advances in imaging of PDAC in the field of image/data acquisition, tumor detection, tumor characterization, treatment response evaluation, and preoperative planning. In addition, current applications of radiomics and AI in the field of PDAC are discussed.