Conversion Surgery for Advanced Pancreatic Cancer

Construction and validation of a nomogram for cancer specific survival of postoperative pancreatic cancer based on the SEER and China database

BACKGROUND

The recurrence rate and mortality rate among postoperative pancreatic cancer patients remain elevated. This study aims to develop and validate the cancer-specific survival period for individuals who have undergone pancreatic cancer surgery.

METHODS

We extracted eligible data from the Surveillance, Epidemiology, and End Results database and randomly divided all patients into a training cohort and an internal validation cohort. External validation was performed using a separate Chinese cohort. The nomogram was developed using significant risk factors identified through univariate and multivariate Cox proportional hazards regression. The effectiveness of the nomogram was assessed using the area under the time-dependent curve, calibration plots, and decision curve analysis. Kaplan-Meier survival curves were utilized to visualize the risk stratification of nomogram and AJCC stage.

RESULTS

Seven variables were identified through univariate and multivariate analysis to construct the nomogram. The consistency index of the nomogram for predicting overall survival was 0.683 (95% CI: 0.675-0.690), 0.689 (95% CI: 0.677-0.701), and 0.823 (95% CI: 0.786-0.860). The AUC values for the 1- and 2-year time-ROC curves were 0.751 and 0.721 for the training cohort, 0.731 and 0.7554 for the internal validation cohort, and 0.901 and 0.830 for the external validation cohorts, respectively. Calibration plots demonstrated favorable consistency between the predictions of the nomogram and actual observations. Moreover, the decision curve analysis indicated the clinical utility of the nomogram, and the risk stratification of the nomogram effectively identified high-risk patients.

CONCLUSION

The nomogram guides clinicians in assessing the survival period of postoperative pancreatic cancer patients, identifying high-risk groups, and devising tailored follow-up strategies.

Advancements in Preclinical Models of Pancreatic Cancer

ABSTRACT

Pancreatic cancer remains one of the deadliest of all cancer types with a 5-year overall survival rate of just 12%. Preclinical models available for understanding the disease pathophysiology have evolved significantly in recent years. Traditionally, commercially available 2-dimensional cell lines were developed to investigate mechanisms underlying tumorigenesis, metastasis, and drug resistance. However, these cells grow as monolayer cultures that lack heterogeneity and do not effectively represent tumor biology. Developing patient-derived xenografts and genetically engineered mouse models led to increased cellular heterogeneity, molecular diversity, and tissues that histologically represent the original patient tumors. However, these models are relatively expensive and very timing consuming. More recently, the advancement of fast and inexpensive in vitro models that better mimic disease conditions in vivo are on the rise. Three-dimensional cultures like organoids and spheroids have gained popularity and are considered to recapitulate complex disease characteristics. In addition, computational genomics, transcriptomics, and metabolomic models are being developed to simulate pancreatic cancer progression and predict better treatment strategies. Herein, we review the challenges associated with pancreatic cancer research and available analytical models. We suggest that an integrated approach toward using these models may allow for developing new strategies for pancreatic cancer precision medicine.

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.

Neoadjuvant Therapy for Duodenal and Ampullary Adenocarcinoma: A Systematic Review

BACKGROUND

The role of systemic therapy in the management of ampullary (AA) and duodenal adenocarcinoma (DA) remains poorly understood. This study sought to synthesize current evidence supporting the use of neoadjuvant therapy (NAT) in AA and DA.

METHODS

The study searched PubMed, Cochrane Library (Wiley), Embase (Elsevier), CINAHL (EBSCO), and ClinicalTrials.gov databases for observational or randomized studies published between 2002 and 2022 evaluating survival outcomes for patients with non-metastatic AA or DA who received systemic therapy and surgical resection. The data extracted included overall survival, progression-free survival, and pathologic response (PR) rate.

RESULTS

From the 347 abstracts identified in this study, 29 reports were reviewed in full, and 15 were included in the final review. The selected studies published from 2007 to 2022 were retrospective. Eight were single-center studies; five used the National Cancer Database (NCDB); and two were European multicenter/national studies. Overall, no studies identified survival differences between NAT and upfront surgery (with or without adjuvant therapy). Two NCDB studies reported longer survival with NAT/AT than with surgery. Five single-center studies reported a significant portion of NAT patients who achieved PR, and one study identified major PR as an independent predictor of survival. Other outcomes associated with NAT included conversion from unresectable to resectable disease, reduced lymph node positivity, and decreased local recurrence rate.

CONCLUSION

Evidence supporting the use of NAT in AA and DA is weak. No randomized studies exist, and observational data show mixed results. For patients with DA and AA, NAT appears safe, but better evidence is needed to understand the preferred multidisciplinary management of DA and AA periampullary malignancies.

Oncological Outcome of Conversion Surgery After Preoperative Chemotherapy for Metastatic Pancreatic Cancer

OBJECTIVE

To investigate the outcome of conversion surgery in patients with metastatic pancreatic cancer (mPDAC) and to identify patients who may benefit from this approach.

BACKGROUND

The role of conversion surgery in patients with mPDAC and exceptional response to chemotherapy remains unclear.

METHODS

Patients who underwent surgical exploration for mPDAC following chemotherapy between 2006 and 2019 were included. Data on demographics, oncologic treatment, pathology, and postoperative outcomes were analyzed. Univariate and multivariate survival analyses were performed.

RESULTS

Some 173 patients received preoperative chemotherapy and underwent surgical exploration. Ninety-three patients underwent resection of the primary tumor and metastatic sites, 80 patients underwent exploration only. In the resection subgroup, 45 patients had complete pathological response of metastases (ypM0) and 48 patients had residual metastases (ypM1). ypM0 status was associated with lower carcinoembryonic antigen levels and lower ypN stage. Overall survival after resection was 25.5 months in ypM0, 10.7 months in ypM1, and 8.1 months in patients without resection ( P <0.001). Additional adjuvant chemotherapy was significantly associated with prolonged survival in resected patients (29.0 vs 14.8 mo, P =0.024) as well as in ypM0 (29.1 vs 19.2 mo, P =0.047). Multivariable analysis identified conversion surgery, carbohydrate antigen 19-9 (CA19-9) and time of resection as independent prognostic markers for the entire cohort. CA19-9, ypM0 and adjuvant treatment were independent predictors of survival in the resection subgroup.

CONCLUSION

In patients with mPDAC and ypM0 status after chemotherapy, surgical resection is associated with encouraging survival. mPDAC patients with exceptional response to chemotherapy may be candidates for exploration and for resection in ypM0. Adjuvant chemotherapy may provide an additional survival advantage.

A case of pathological complete response with liposomal irinotecan + 5-FU/LV for unresectable locally advanced pancreatic cancer

Background

Pancreatic cancer has one of the worst prognoses of any all cancers. 5-FU/leucovorin + irinotecan + oxaliplatin (FOLFIRINOX), gemcitabine (GEM) plus nab-paclitaxel regimens have been recognized as global-standard, first-line treatments for patients with advanced pancreatic cancer. The liposomal irinotecan (nal-IRI) + 5-FU/LV regimen is now included in treatment guidelines as a recommended and approved option for use in patients with metastatic pancreatic cancer that has progressed after GEM-based therapy and who have a suitable performance status and comorbidity profile. There is no report that nal-IRI + 5-FU/LV regimen was significantly effective, and we will report it because we experienced this time.

Case presentation

A 69-year-old man presented with epigastric pain, and a contrast computed tomography (CT) revealed an enhanced mass lesion measuring 33 × 27 mm on the pancreatic body with encasement of the common hepatic artery (CHA) and the splenic vein. An endoscopic ultrasound-guided fine needle aspiration was performed and demonstrated cytology consistent with adenocarcinoma. Therefore, we diagnosed the patient with unresectable locally advanced pancreatic cancer. The patient received the GEM and S-1 regimen; however, the adverse event was relatively severe. Then, 11 cycles of nal-IRI + 5-FU/LV regimen were administered. A CT scan revealed that the tumor had shrunk to 18 × 7 mm in diameter with encasement of the CHA. The encasement of the splenic vein had disappeared, without any distant metastases. From this post-chemotherapy evaluation and intraoperative frozen section of around the celiac artery, gastroduodenal artery and pancreas stump confirmed absence of tumor cells, we performed distal pancreatectomy with celiac axis resection. A histological examination of the surgical specimen revealed no evidence of residual adenocarcinoma, consistent with a pathological complete response to treatment.

Conclusions

We present the first case of a pathological complete response with nal-IRI + 5-FU/LV for unresectable, locally advanced pancreatic cancer. In the future, nal-IRI may become a key drug for pancreatic cancer treatment.

An evaluation of adjuvant chemotherapy following neoadjuvant chemotherapy and resection for borderline resectable and locally advanced pancreatic cancer

BACKGROUND

In borderline resectable and locally advanced (BRLA) pancreatic cancer patients, the role of adjuvant therapy (AT) after neoadjuvant therapy (NAT) and curative-intent resection is poorly understood.

METHODS

Using the National Cancer Database (NCDB) between 2011 and 2017, we identified BRLA patients who received NAT and resection. Kaplan-Meier analysis and multivariable Cox proportional hazards (PH) regression were performed to examine the association between AT and overall survival (OS).

RESULTS

Of 17,905 BRLA patients identified, 764 received NAT and resection, of which 203 received AT. Median age was 63 years, and 53.1% were female. Kaplan Meier analysis revealed no differences in median OS between AT vs non-AT groups (28.9 vs 30.1months, p = 0.498). In the multivariable Cox PH model, after adjusting for other factors, when margin was positive, AT was associated with an improved survival (HR 0.54, 95%CI 0.32-0.90, p = 0.031).

CONCLUSION

AT was not associated with survival in BRLA patients who received NAT and resection except in patients with positive margins. Further research is necessary to better understand the role of AT following NAT in patients with BRLA.

Predictive model for the intraoperative unresectability of hilar cholangiocarcinoma: Reducing futile surgical exploration

Introduction

Surgical exploration is widely performed in hilar cholangiocarcinoma (HCCA), but the intraoperative resectability rate is only 60%-80%. Exploration substantially increases pain and mental stress, and the costs and length of hospital stay are considerably increased. Identifying preoperative risk factors associated with unresectability could decrease unnecessary exploration.

Materials and methods

In total, 440 HCCA patients from multiple centers were enrolled. Those receiving surgical exploration were divided into the resected and unresected groups. Morphological variables including Bismuth classification, lymph node metastasis and vessel invasion were obtained from radiological exams. Logistic regression for the training cohort was used to identify risk factors for unresectability, and a nomogram was constructed to calculate the unresectability rate. A calibration curve assessed the power of the nomogram.

Results

Among 311 patients receiving surgical exploration, 45 (14.7%) were unresectable by intraoperative judgment. Compared with the resected group, unresected patients had similar costs (p = 0.359) and lengths of hospital stay (p = 0.439). Multivariable logistic regression of the training cohort (235 patients) revealed that CA125, Bismuth-Corlette type IV, lymph node metastasis and hepatic artery invasion were risk factors for unresectability. Liver atrophy (p = 0.374) and portal vein invasion (p = 0.114) were not risk factors. The nomogram was constructed based on the risk factors. The concordance index (C-index) values of the calibration curve for predicting the unresectability rate of the training and validation (76 patients) cohorts were 0.900 (95% CI, 0.835–0.966) and 0.829 (95% CI, 0.546–0.902), respectively.

Conclusion

Analysis of preoperative factors could reveal intraoperative unresectability and reduce futile surgical explorations, ultimately benefiting HCCA patients.

Ablative Radiotherapy (ART) for Locally Advanced Pancreatic Cancer (LAPC): Toward a New Paradigm?

Locally advanced pancreatic cancer (LAPC) represents a major urgency in oncology. Due to the massive involvement of the peripancreatic vessels, a curative-intent surgery is generally precluded. Historically, LAPC has been an indication for palliative systemic therapy. In recent years, with the introduction of intensive multi-agent chemotherapy regimens and aggressive surgical approaches, the survival of LAPC patients has significantly improved. In this complex and rapidly evolving scenario, the role of radiotherapy is still debated. The use of standard-dose conventional fractionated radiotherapy in LAPC has led to unsatisfactory oncological outcomes. However, technological advances in radiation therapy over recent years have definitively changed this paradigm. The use of ablative doses of radiotherapy, in association with image-guidance, respiratory organ-motion management, and adaptive protocols, has led to unprecedented results in terms of local control and survival. In this overview, principles, clinical applications, and current pitfalls of ablative radiotherapy (ART) as an emerging treatment option for LAPC are discussed.

Conversion surgery for undifferentiated carcinoma with osteoclast-like giant cells of the pancreas: a case report

Background

Undifferentiated carcinoma with osteoclast-like giant cells (UCOGCs) is a rare subtype of pancreatic cancer (PC), and its clinicopathological characteristics are still unclear. Herein, we report a case of initially unresectable UCOGC that was successfully resected after FOLFIRINOX therapy.

Case presentation

A 63-year-old man was referred to us for evaluation of a pancreatic mass detected by computed tomography (CT) during a medical checkup. Computed tomography showed a 7.5-cm tumor located in the pancreatic head and body, which involved the common hepatic artery (CHA), gastroduodenal artery (GDA), and main portal vein (PV) with tumor thrombus. UCOGC was suspected by endoscopic ultrasonography-guided fine needle aspiration, and the patient was diagnosed with unresectable locally advanced pancreatic cancer. After ten cycles of FOLFIRINOX, the tumor size decreased to 3 cm and the tumor thrombus in the main portal trunk had disappeared in the follow-up CT scan. However, the patient experienced severe adverse drug reactions, including neutropenia and liver dysfunction. Therefore, we performed pancreatoduodenectomy with portal vein resection. The pathological diagnosis was UCOGC with a negative tumor margin. He was treated with FOLFIRINOX, and remains recurrence-free for 6 months after surgery.

Conclusions

We experienced a case undergoing conversion surgery for unresectable UCOGC, which resulted in R0 resection. FOLFIRINOX could be a possible regimen to achieve conversion surgery for UCOGC.

Verification of Resectability Status for Pancreatic Cancer: Radiological and Pathological Analysis of Patients Undergoing Pancreatoduodenectomy With Combined Resection of the Superior Mesenteric Artery

OBJECTIVES

Resectability status is considered an important indicator for progression of pancreatic cancer. We verified the superior mesenteric artery (SMA) factors of resectability status by radiological and pathological analysis in patients who underwent pancreatoduodenectomy with combined resection of the SMA.

METHODS

We enrolled 22 patients who underwent pancreatoduodenectomy with combined resection of the SMA. Patients were divided into 3 groups according to the contact angle between the tumor and the SMA in preoperative computed tomography images (no contact, R-sma; contact within 180 degrees, BR-sma; contact more than 180 degrees, UR-sma). We pathologically evaluated cancer progression toward the SMA.

RESULTS

There were 3 patients with R-sma, 12 with BR-sma, and 7 with UR-sma. The median distance (mm) between the cancer and the SMA was 7.0 with R-sma, 1.0 with BR-sma, and 0 with UR-sma (P = 0.0003). Invasion to the superior mesenteric nerve plexus was positive in none with R-sma, 11 with BR-sma, and 7 with UR-sma (P < 0.0001). Invasion to the SMA was positive in none with R-sma and BR-sma, and 7 with UR-sma (P < 0.0001).

CONCLUSIONS

Superior mesenteric artery factors of resectability status are reliable indicator for cancer progression toward the SMA.

Predictors of conversion surgery in patients with pancreatic cancer who underwent neoadjuvant or palliative FOLFIRINOX treatment using baseline and follow-up CT

PURPOSE

We aimed to evaluate the predictive factors of conversion surgery in pancreatic adenocarcinoma (PAC) after neoadjuvant or palliative FOLFIRINOX using baseline and follow-up CT.

METHODS

We retrospectively included 189 patients who had undergone more than 4 cycles of FOLFIRINOX. We reviewed baseline CT (B-CT), 1st follow-up CT (1st-CT), and the preoperative or last follow-up CT (L-CT) and determined tumor size changes according to the Response Evaluation Criteria in Solid Tumors (RECIST 1.1). Extra-pancreatic perineural invasion (EPNI) and resectability using NCCN 2019 guideline were evaluated. Subgroup analysis by baseline resectability was performed.

RESULTS

B-CT included resectable (n = 25, 23.2%), borderline (n = 55, 29.1%), locally advanced (n = 44, 23.3%), and metastatic (n = 65, 34.4%) PAC. Seventy-four patients had undergone surgery (39.2%) with an 83.8% (62/74) R0 resection. For operability, resectable status at L-CT (hazard ratio (HR) 65.5; 95% confidence interval (CI) 5.0-865; P = 0.002), RECIST (partial response) at 1st-CT (HR 3.6; 95% CI 1.1-11.7; P = 0.032), and baseline borderline resectability (HR 8.6; 95% CI 1.6-46.4; P = 0.013) were important predictors. Based on a size reduction cut-off of 22.2%, the area under the receiver operating characteristic (ROC) curve (Az) was 0.761 (sensitivity = 70.3%, specificity = 74.8%). In subgroup analysis, RECIST (partial response) at 1st-CT was a significant predictor of locally advanced PAC (HR 32; 95% CI 4.5-227, P 0.001), and the optimal cut-off was 22.2% (Az = 0.914; sensitivity = 100%, specificity = 75%). Baseline tumor size ([Formula: see text] 4 cm) (HR 5.6, 95% CI 1.3-24.3, P = 0.022) and unresectable status at 1st-CT (HR 4.8, 95% CI 1.1-20.6, P = 0.035) were significantly associated with margin-positive resection.

CONCLUSION

Both baseline and follow-up CT findings are useful to predict conversion surgery for PAC after FOLFIRINOX.

Survival Benefit Associated With Resection of Locally Advanced Pancreatic Cancer Following Upfront FOLFIRINOX versus FOLFIRINOX Only: Multicenter Propensity Score-Matched Analysis

OBJECTIVE

This study compared median overall survival (OS) after resection of locally advanced pancreatic cancer (LAPC) following upfront FOLFIRINOX versus a propensity-score matched cohort of LAPC patients treated with FOLFIRINOX-only (i.e. without resection).

BACKGROUND

Since the introduction of FOLFIRINOX chemotherapy, increased resection rates in LAPC patients have been reported, with improved OS. Some studies have also reported promising OS with FOLFIRINOX-only treatment in LAPC. Multicenter studies assessing the survival benefit associated with resection of LAPC versus patients treated with FOLFIRINOX-only are lacking.

METHODS

Patients with non-progressive LAPC after 4 cycles of FOLFIRINOX treatment, both with and without resection, were included from a prospective multicenter cohort in 16 centers (April 2015-December 2019). Cox regression analysis identified predictors for OS. One-to-one propensity score matching (PSM) was used to obtain a matched cohort of patients with and without resection. These patients were compared for OS.

RESULTS

Overall, 293 patients with LAPC were included, of whom 89 underwent a resection. Resection was associated with improved OS (24 vs 15 months, p<0.01), as compared to patients without resection. Before PSM, resection, Charlson Comorbidity Index, and RECIST response were predictors for OS. After PSM, resection remained associated with improved OS (HR 0.344, 95% CI [0.222-0.534], p<0.01), with an OS of 24 vs 15 months, as compared to patients without resection. Resection of LAPC was associated with improved 3-year OS (31% vs 11%, p<0.01).

CONCLUSION

Resection of LAPC following FOLFIRINOX was associated with increased OS and 3-year survival, as compared to propensity-score matched patients treated with FOLFIRINOX-only.

[Surgery for periampullary pancreatic cancer]

Periampulläre Neoplasien sind eine heterogene Gruppe verschiedener Tumorentitäten der periampullären Region, von denen das Pankreasadenokarzinom mit 60–70 % am häufigsten ist. Wie typisch für Pankreaskarzinome zeichnen sich periampulläre Pankreaskarzinome durch ein aggressives Wachstum und eine frühe systemische Progression aus. Aufgrund ihrer besonderen Lage in unmittelbarer Nähe zur Papilla Vateri treten Symptome in eher früherem Tumorstadium auf, sodass die Therapiemöglichkeiten und Prognose insgesamt günstiger sind als bei Pankreaskarzinomen anderer Lokalisation. Trotzdem unterscheiden sich die Therapieprinzipien bei periampullären Pankreaskarzinomen nicht wesentlich von den Standards bei Pankreaskarzinomen anderer Lokalisation. Ein potenziell kurativer Therapieansatz beim nichtmetastasierten periampullären Pankreaskarzinom ist multimodal und besteht aus der Durchführung einer partiellen Duodenopankreatektomie als radikale onkologische Resektion in Kombination mit einer systemischen, meist adjuvant verabreichten Chemotherapie. Bei Patienten mit günstigen prognostischen Faktoren kann hierdurch ein Langzeitüberleben erzielt werden. Zudem wurden mit der Weiterentwicklung der Chirurgie und Systemtherapie auch potenziell kurative Therapiekonzepte für fortgeschrittene, früher irresektable Tumoren etabliert, welche nun nach Durchführung einer neoadjuvanten Therapie oft einer Resektion zugeführt werden können. In diesem Beitrag werden die aktuellen chirurgischen Prinzipien der radikalen onkologischen Resektion periampullärer Pankreaskarzinome im Kontext der multimodalen Therapie dargestellt und ein Ausblick auf mögliche künftige Entwicklungen der Therapie gegeben.

Margin Accentuation Irreversible Electroporation in Stage III Pancreatic Cancer: A Systematic Review

Simple Summary

This literature review shows preliminary evidence to suggest that electroporation, the use of electricity to cause the death of cells around the tumour, may be associated with an improved survival and complete resection rates following pancreatic surgery for higher stage pancreatic cancer. However, one in five patients have a complication from the procedure that alters their normal course in hospital. Moreover, the number of patients who underwent this technique is small and further data is needed to support the preliminary evidence. The results therefore should be interpreted with caution.

Abstract

The present systematic review aimed to summarise the available evidence on indications and oncological outcomes after MA IRE for stage III pancreatic cancer (PC). A literature search was performed in the Pubmed, MEDLINE, EMBASE, SCOPUS databases using the PRISMA framework to identify all MA IRE studies. Nine studies with 235 locally advanced (LA) (82%, 192/235) or Borderline resectable (BR) PC (18%, 43/235) patients undergoing MA IRE pancreatic resection were included. Patients were mostly male (56%) with a weighted-mean age of 61 years (95% CI: 58–64). Pancreatoduodenectomy was performed in 51% (120/235) and distal pancreatectomy in 49% (115/235). R0 resection rate was 73% (77/105). Clavien Dindo grade 3–5 postoperative complications occurred in 19% (36/187). Follow-up intervals ranged from 3 to 29 months. Local and systematic recurrences were noted in 8 and 43 patients, respectively. The weighted-mean progression free survival was 11 months (95% CI: 7–15). The weighted-mean overall survival was 22 months (95% CI 20–23 months) and 8 months (95% CI 1–32 months) for MA IRE and IRE alone, respectively. Early non-randomised data suggest MA IRE during pancreatic surgery for stage III pancreatic cancer may result in increased R0 resection rates and improved OS with acceptable postoperative morbidity. Further, larger studies are warranted to corroborate this evidence.

Radiological evaluation of pancreatic cancer: What is the significance of arterial encasement >180° after neoadjuvant treatment?

PURPOSE

This study aimed to evaluate contrast-enhanced computed tomography (CE-CT) features for prediction of arterial tumor invasion in pancreatic cancer (PDAC) patients in the event of arterial encasement >180° after neoadjuvant (radio-)chemotherapy (NAT).

METHODS

Seventy PDAC patients with seventy-five arteries showing encasement >180° after completion of NAT were analyzed. All patients underwent surgical exploration with either tumor resection including arterial resection, periadventitial dissection (arterial divestment) or confirmation of locally irresectable disease. CE-CT scans were assessed regarding tumor extent and artery-specific imaging features. The results were analyzed on a per-artery basis. Based on the intraoperative and histopathological findings, encased arteries were classified as either invaded or non-invaded.

RESULTS

Eighteen radiologically encased arteries were resected; of these, nine had pathologic evidence for tumor invasion. In 42 encased arteries, the tumor could be removed by arterial divestment. In 13 patients with 15 encased arteries, the tumor was deemed technically irresectable. Median tumor size, length of solid soft tissue contact, and degree of circumferential contiguity by solid soft tissue along the artery in CE-CT were significantly lower in the non-invaded than in the invaded artery group (p ≤ 0.017). Imaging features showed moderate accuracies for prediction of arterial invasion (≤72.0 %). The thresholds ≤26 mm for post-NAT solid soft tissue contact and ≤270° for circumferential contiguity by solid soft tissue had high negative predictive values (≥87.5 %).

CONCLUSION

Although post-NAT prediction of arterial invasion remains difficult, arteries with ≤270° contiguity by soft tissue and arteries with ≤26 mm length of solid soft tissue contact are unlikely to be invaded, with possible implications for surgical planning.