Prognostic importance of peritoneal washing cytology in patients with otherwise resectable pancreatic ductal adenocarcinoma who underwent pancreatectomy: A nationwide, cancer registry–based study from the Japan Pancreas Society

Safety and feasibility of percutaneous abdominal lavage cytology screening (PACS) prior to surgical resection for pancreatic cancer

PURPOSE

This study aimed to evaluate the feasibility, safety, diagnostic yield, and technical aspects of percutaneous abdominal lavage cytology screening (PACS) in patients with resectable pancreatic cancer.

METHODS

This single-center, retrospective study included patients with resectable pancreatic cancer who underwent PACS before pancreatectomy between May 2022 and October 2023. The technical success rate, position of the drainage tube, volume of fluid administered, volume of fluid retrieved, fluid retrieval rate, and adverse events were evaluated. The cytological results of PACS were compared with those of surgical peritoneal lavage performed during pancreatectomy.

RESULTS

Forty-four patients were enrolled in this study. The technical success rate for PACS was 100%. Drainage tube placement was outside the pouch of Douglas in all patients in the right-sided abdominal approach group (n = 10), whereas the placement was in the pouch of Douglas in all patients in the suprapubic approach group (n = 34). The mean volume of fluid administered, mean volume of fluid retrieved, and fluid retrieval rate were 185.0 ± 22.9 ml vs. 97.1 ± 32.0 ml (p < 0.001), 36.8 ± 25.6 ml vs. 50.5 ± 21.6 ml (p = 0.059), and 19.0 ± 12.4% vs. 54.9 ± 21.9% (p < 0.001) in the right abdominal approach and suprapubic approach groups, respectively. No adverse events were reported. The cytological results were benign in 42 patients; no discrepancy was observed in the results of surgical peritoneal lavage (n = 36).

CONCLUSION

PACS is a feasible and safe procedure that can be performed before pancreatectomy in patients with resectable pancreatic cancer. the suprapubic approach may be ideal and PACS could be a screening method to detect carcinomatous peritonitis.

Use of Diagnostic Laparoscopy and Peritoneal Washings for Pancreatic Cancer

Pancreatic adenocarcinoma is an aggressive malignancy that often presents with advanced disease. Accurate staging is essential for treatment planning and shared decision-making with patients. Staging laparoscopy is a minimally invasive procedure that can detect radiographically occult metastatic disease. Its routine use with the collection of peritoneal washings in patients with pancreatic cancer remains controversial. We, herein, review the current literature concerning staging laparoscopy and peritoneal washings in patients with pancreatic cancer.

Optimal treatment strategy for patients with pancreatic cancer having positive peritoneal cytology: A nationwide multicenter retrospective cohort study supervised by the Japanese Society of Hepato-Biliary-Pancreatic Surgery

BACKGROUND

The aim of this study was to determine the optimal treatment for patients with pancreatic cancer (PaCa) having positive peritoneal cytology (PPC).

METHODS

This multicenter retrospective study included patients with PPC treated at 78 high-volume centers between January 2012 and December 2020. Prognoses after resection (S-group) and initiation of nonsurgical treatment (N-group) were compared. Prognostic factors for survival in both groups were analyzed. Detailed characteristics of conversion surgery (CS) in the N-group were evaluated.

RESULTS

In total, 568 enrolled patients were classified into an S-group (n = 445) or an N-group (n = 123). Median survival times (MSTs) were 19.0 months and 19.3 months, respectively, with no significant difference in prognosis (p = .845). The intervenable prognostic factors for survival were adjuvant treatment in the S-group (p < .001) and CS in the N-group (p < .001). Following CS, the MST was prolonged to 45.6 months, and peritoneal or liver recurrence decreased considerably. CS can be expected if PPC is diagnosed before neoadjuvant treatment and when combination treatment is initiated.

CONCLUSION

Surgical resection may not be beneficial for improving survival when PPC is evident. Chemotherapy aiming for CS may be the optimal treatment for such patients.

Molecular diagnosis for detecting KRAS mutation in peritoneal washing fluid of pancreatic ductal adenocarcinoma

Positive peritoneal washing cytology is an indicator of poor prognosis in patients with pancreatic ductal adenocarcinoma (PDAC); however, its sensitivity is relatively low. This study evaluated the performance of peptide nucleic acid (PNA)-directed PCR clamping as a molecular-based peritoneal washing cytology for sensitive detection of KRAS mutation in PDAC. Intraoperative peritoneal washing fluid (IPWF) obtained from patients with PDAC who underwent surgery was analyzed. PNA-directed PCR clamping was performed on DNA extracted from IPWF. Among 54 patients enrolled, threshold cycle (Ct) was significantly lower in patients with positive peritoneal washing cytology than in those with negative peritoneal washing cytology (P < 0.001) and in patients with peritoneal dissemination than in those without peritoneal dissemination (P < 0.01). The optimal Ct cut-off to predict KRAS mutations in IPWF was 36.42 based on a receiver operating characteristic curve. The sensitivity, specificity, and accuracy for molecular diagnosis were 100%, 80.0%, and 85.2%, respectively. Peritoneal dissemination recurrence was significantly more frequent in patients with a positive molecular diagnosis than in those with a negative diagnosis (38.9 vs. 8.0%, P = 0.013). The genomic approach might be clinically valuable for a more precise tumor cell detection in IPWF.

Peritoneal washing cytology status as a crucial prognostic determinant in patients with localized pancreatic ductal adenocarcinoma who underwent curative-intent resection following preoperative chemoradiotherapy

BACKGROUND

Prognostic implications of peritoneal washing cytology (CY) in patients with localized pancreatic ductal adenocarcinoma (PDAC) undergoing surgical resection following preoperative chemoradiotherapy (CRT) remain unclear. This study aimed to elucidate the prognostic significance and predictors of a positive CY status (CY+) after preoperative CRT.

METHODS

Clinical data from 141 patients with localized PDAC who underwent curative-intent resection after preoperative CRT were retrospectively analyzed to examine the association between CY+ and clinicopathological factors and survival.

RESULTS

CY+ was observed in six patients (4.3%). The CY+ group exhibited significantly higher preoperative serum levels of CA19-9 and a substantially greater incidence of tumor location in the pancreatic body or tail, along with pathological invasion to the anterior pancreatic capsule, than the CY- group. The CY+ group had a significantly higher incidence of peritoneal recurrence compared with the CY- group (83.3% vs. 18.5%, p = 0.002). Overall survival (OS) and recurrence-free survival (RFS) after surgery were significantly shorter in the CY+ group than in the CY- group (CY+ vs. CY-: 18.3 vs. 46.2 months, p = 0.001, and 8.9 vs. 17.7 months, p = 0.009, respectively). Multivariate analyses identified CY+ as an independent prognostic factor for worse OS (hazard ratio 5.00, 95% confidence interval 1.03-12.31) and RFS (hazard ratio 2.58, 95% confidence interval 1.04-6.43). Local invasion grade on imaging before CRT, limited histological response to CRT, and absence of adjuvant chemotherapy were independent predictors of worse OS and RFS.

CONCLUSION

Despite the relatively low incidence of CY+ after preoperative CRT, it emerged as an independent prognostic factor in patients with localized PDAC undergoing curative-intent resection following preoperative CRT.

Impact of endoscopic ultrasound-guided fine needle aspiration on positive peritoneal lavage cytology in patients with resectable pancreatic body and tail cancer

BACKGROUND/PURPOSE

A recent study has demonstrated that the timing of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) significantly influences the peritoneal lavage cytology (CY) outcomes in pancreatic body-tail cancer. The aim of this study was to clarify the impact of EUS-FNA on CY positivity in patients with resectable pancreatic body-tail cancer.

METHODS

Patients with anatomically resectable pancreatic body-tail cancer surgically resected at Hiroshima University Hospital were enrolled, and elated clinicopathological factors, including EUS-FNA variables and CY positivity rate, were analyzed.

RESULTS

Of the 129 eligible patients, 16 (12%) had positive CY. The EUS-FNA rates of the CY-positive and CY-negative groups were not significantly different (63% vs. 52%, p = .440). Multivariate analysis revealed that lymph node metastasis was the only independent risk factor for CY positivity (odds ratio: 5.734, p = .031). A total of 10 (14%) of the 69 patients who underwent EUS-FNA had positive CY; however, needle specifications and the interval between EUS-FNA and CY examination did not differ between the CY-positive and CY-negative groups. CY positivity rates were comparable for intervals ≤14 days and ≥15 days (17% vs. 14%, p = 1.000).

CONCLUSIONS

EUS-FNA may not affect CY positivity in patients with resectable pancreatic body-tail cancer, regardless of the timing.

Deep learning predicts the 1-year prognosis of pancreatic cancer patients using positive peritoneal washing cytology

Peritoneal washing cytology (CY) in patients with pancreatic cancer is mainly used for staging; however, it may also be used to evaluate the intraperitoneal status to predict a more accurate prognosis. Here, we investigated the potential of deep learning of CY specimen images for predicting the 1-year prognosis of pancreatic cancer in CY-positive patients. CY specimens from 88 patients with prognostic information were retrospectively analyzed. CY specimens scanned by the whole slide imaging device were segmented and subjected to deep learning with a Vision Transformer (ViT) and a Convolutional Neural Network (CNN). The results indicated that ViT and CNN predicted the 1-year prognosis from scanned images with accuracies of 0.8056 and 0.8009 in the area under the curve of the receiver operating characteristic curves, respectively. Patients predicted to survive 1 year or more by ViT showed significantly longer survivals by Kaplan-Meier analyses. The cell nuclei found to have a negative prognostic impact by ViT appeared to be neutrophils. Our results indicate that AI-mediated analysis of CY specimens can successfully predict the 1-year prognosis of patients with pancreatic cancer positive for CY. Intraperitoneal neutrophils may be a novel prognostic marker and therapeutic target for CY-positive patients with pancreatic cancer.

Impact of endoscopic ultrasound-guided tissue acquisition on prognosis and peritoneal lavage cytology in resectable or borderline resectable pancreatic ductal adenocarcinoma

OBJECTIVES

This study aimed to evaluate the clinical impact of preoperative endoscopic ultrasound-guided tissue acquisition (EUS-TA) on the prognosis and incidence of positive peritoneal lavage cytology (PLC) during laparotomy or staging laparoscopy in patients with resectable (R) or borderline resectable (BR) pancreatic ductal adenocarcinoma (PDAC).

METHODS

We retrospectively collected data from patients diagnosed with body and tail PDAC with/without EUS-TA at our hospital from January 2006 to December 2021.

RESULTS

To examine the effect of EUS-TA on prognosis, 153 patients (122 in the EUS-TA group, 31 in the non-EUS-TA group) were analyzed. There was no significant difference in overall survival between the EUS-TA and non-EUS-TA groups after PDAC resection (P = 0.777). In univariate and multivariate analysis, preoperative EUS-TA was not identified as an independent factor related to overall survival after pancreatectomy [hazard ratio 0.96, 95 % confidence interval (CI) 0.54-1.70, P = 0.897]. Next, to examine the direct influence of EUS-TA on the results of PLC, 114 patients (83 in the EUS-TA group and 31 in the non-EUS-TA group) were analyzed. Preoperative EUS-TA was not statistically associated with positive PLC (odds ratio 0.73, 95 % CI 0.25-2.20, P = 0.583). After propensity score matching, overall survival and positive PLC were the same in both groups.

CONCLUSIONS

EUS-TA had no negative impact on postoperative survival and PLC-positive rates in R/BR PDAC.

Japanese classification of pancreatic carcinoma by the Japan Pancreas Society: Eighth edition

In 2023, the Japan Pancreas Society (JPS) published the new eighth edition of the Japanese classification of pancreatic carcinoma. We present here an excerpted version in English, based on the latest edition. The major changes in this revision are as follows: In the eighth edition of the Union for International Cancer Control (UICC), the T category was changed to be based on tumor size; however, the eighth edition of the Japanese classification retains the previous T category based on local invasion factors. Lymph nodes have been renamed, and regional lymph nodes have been defined by location. Peritoneal cytology, which was not previously included in distant metastasis (M), has now been included in the M category. Moreover, significant additions have been made regarding the pathological diagnosis of endoscopic ultrasound-guided fine-needle aspiration biopsy (EUS-FNAB) and criteria for histological assessment of the effects after chemotherapy and radiation therapy. Although this classification is aimed at carcinoma originating in the pancreas, not in the bile duct or duodenum, if the differentiation of the primary organ is difficult, this classification should be applied. It is also desirable to describe tumors other than carcinoma and metastatic tumors to the pancreas in accordance with this classification.

Scoring system to predict positive peritoneal cytology in patients with resectable and borderline resectable pancreatic cancer

BACKGROUND

The aim of this study was to evaluate factors to predict positive peritoneal cytology, whcih would determine the indication for staging laparoscopy in pancreatic cancer.

METHODS

A total of 430 patients that underwent pancreatectomy for resectable and borderline resectable pancreatic cancer were retrospectively reviewed.

RESULTS

Among 430 patients, 36 had positive cytology (8.4%). Median survival time in negative cytology was 24.7 months, compared with 15.1 months in positive cytology (p = .004). Factors to predict positive cytology in pancreatic cancer according to multivariate analysis were tumor location (body, tail; OR 2.66; 95% CI: 1.21-5.85; p = .015), tumor size ≥30 mm (OR 2.95; 95% CI: 1.35-6.47; p = .007) and radiographic other-organ invasion (HR 2.79; 95% CI: 1.01-7.67; p = .047). Patients were scored 0 to 3 corresponding with these factors. Rates of positive cytology increases in each score were: score 0: 2.9%, score 1: 6.7%, score 2: 18.3%, score 3: 36.8%.

CONCLUSIONS

Tumor location (body or tail), tumor size ≥30 mm, and radiographic other-organ invasions were risk factors for positive cytology in pancreatic cancer. This scoring system might be a useful indicator to perform staging laparoscopy to diagnose positive cytology.

Preoperative predictive factors for positive peritoneal cytology results in patients with pancreatic ductal adenocarcinomas: a retrospective study

BACKGROUND

The clinical importance of positive peritoneal cytology results in patients with pancreatic ductal adenocarcinomas remains controversial. We evaluated the prognosis of these patients and the predictive preoperative risk factors for positive peritoneal cytology results.

METHODS

We retrospectively reviewed patients who underwent curative-intent surgery at our institution between May 2010 and June 2020. Preoperative risk factors for positive peritoneal cytology results were identified using logistic regression analysis. A scoring model was constructed using the total number of significant independent predictors for positive peritoneal cytology results.

RESULTS

Of 233 patients, 18 (7.7%) had positive peritoneal cytology results. The recurrence-free survival and cancer-specific survival were markedly worse in patients with positive peritoneal cytology results than in those with negative peritoneal cytology results (recurrence-free survival: 6.0 months vs. 16.6 months, p = 0.050; cancer-specific survival: 19.4 months vs. 47.5 months, p = 0.034). Tumor location (odds ratio: 3.760, 95% confidence interval: 1.099-11.818, p = 0.023), tumor size > 25 mm (odds ratio: 3.410, 95% confidence interval: 1.031-11.277, p = 0.046), preoperative serosal invasion (odds ratio: 5.193, 95% confidence interval: 1.099-24.531, p = 0.038), and preoperative carcinoembryonic antigen level > 5.6 ng/mL (odds ratio: 3.816, 95% confidence interval: 1.248-10.667, p = 0.019) were identified as significant independent predictive factors. Our predictive model's optimal cutoff and positive predictive values for positive peritoneal cytology results were 3 and 27.9%, respectively.

CONCLUSIONS

The indications for curative-intent surgery should be considered carefully in patients with high-risk factors for positive peritoneal cytology results.

Clinical impact of high-quality testing for peritoneal lavage cytology in pancreatic cancer

In pancreatic ductal adenocarcinoma (PDAC) patients, the importance of peritoneal lavage cytology, which indicates unresectability, remains controversial. This study sought to determine whether positive peritoneal lavage cytology (CY+) precludes pancreatectomy. Furthermore, we propose a novel liquid biopsy using peritoneal lavage fluid to detect viable peritoneal tumor cells (v-PTCs) with TelomeScan F35, a telomerase-specific replication-selective adenovirus engineered to express green fluorescent protein. Resectable cytologically or histologically proven PDAC patients (n = 53) were enrolled. CY was conducted immediately following laparotomy. The resulting fluid was examined by conventional cytology (conv-CY; Papanicolaou staining and MOC-31 immunostaining) and by the novel technique (Telo-CY; using TelomeScan F35). Of them, 5 and 12 were conv-CY+ and Telo-CY+, respectively. All underwent pancreatectomy. The two double-CY+ (conv-CY+ and Telo-CY+) patients showed early peritoneal recurrence (P-rec) postoperatively, despite adjuvant chemotherapy. None of the three conv-CY+ Telo-CY- patients exhibited P-rec. Six of the 10 Telo-CY+ conv-CY- patients (60%) relapsed with P-rec. Of the remaining 38 double-CY- [conv-CY-, Telo-CY-, conv-CY± (Class III)] patients, 3 (8.3%) exhibited P-rec. Although conv-CY+ status predicted poor prognosis and a higher risk of P-rec, Telo-CY was more sensitive for detecting v-PTC. Staging laparoscopy and performing conv-CY and Telo-CY are needed to confirm the indication for pancreatectomy.

Evaluating staging laparoscopy indications for pancreatic cancer based on resectability classification and treatment strategies for patients with positive peritoneal washing cytology

Introduction

The prognosis of pancreatic ductal adenocarcinoma (PDAC) in patients with positive peritoneal washing cytology (CY1) is poor. We aimed to evaluate the results of staging laparoscopy (SL) and treatment efficacy in CY1 patients based on a resectability classification.

Methods

We retrospectively reviewed 250 patients with PDAC who underwent SL before the initial treatment between 2017 and 2023 at the University of Toyama.

Results

The breakdown of cases by resectability classification was resectable (R):borderline resectable (BR):unresectable locally advanced (UR-LA) = 131:48:71 cases. The frequency of CY1 increased in proportion to the degree of local progression (R:BR:UR-LA = 20:23:34%), but the frequencies of liver metastasis or peritoneal dissemination were comparable (R:BR:UR-LA = 6.9:6.3:8.5%). Most CY1 patients received gemcitabine along with nab-paclitaxel therapy. The CY-negative conversion rates (R:BR:UR-LA = 70:64:52%) and conversion surgery rates (R:BR:UR-LA = 40:27:9%) were inversely proportional to the degree of local progression.Comparing H0P0CY1 factors for each classification, patients with H0P0CY1 had significantly more pancreatic body or tail carcinoma and tumor size ≥32 mm in R patients, whereas in BR patients, duke pancreatic monoclonal antigen type 2 (DUPAN-2) ≥ 230 U/mL was a significant factor. In contrast, no significant factors were observed in UR-LA patients.

Conclusion

The CY1 rates, CY-negative conversion rates, and conversion surgery rates varied according to local progression. In the case of R and BR, SL could be considered in patients with pancreatic body or tail carcinoma, large tumor size, or high DUPAN-2 level. In UR-LA, SL might be considered for all patients.

Efficacy of staging laparoscopy for resectable pancreatic cancer on imaging and the therapeutic effect of systemic chemotherapy for positive peritoneal cytology

BACKGROUND

The frequency and prognosis of positive peritoneal washing cytology (CY1) in resectable pancreatic ductal adenocarcinoma (R-PDAC) remains unclear. The objective of this study was to identify the clinical implications of CY1 in R-PDAC and staging laparoscopy (SL).

METHODS

We retrospectively analyzed 115 consecutive patients with R-PDAC who underwent SL between 2018 and 2022. Patients with negative cytology (CY0) received radical surgery after neoadjuvant chemotherapy, while CY1 patients received systemic chemotherapy and were continuously evaluated for cytology.

RESULTS

Of the 115 patients, 84 had no distant metastatic factors, 22 had only CY1, and nine had distant metastasis. Multivariate logistic regression revealed that larger tumor size was an independent predictor of the presence of any distant metastatic factor (OR: 6.30, p = .002). Patients with CY1 showed a significantly better prognosis than patients with distant metastasis (MST: 24.6 vs. 18.9 months, p = .040). A total of 11 CY1 patients were successfully converted to CY-negative, and seven underwent conversion surgery. There was no significant difference in overall survival between patients with CY0 and those converted to CY-negative.

CONCLUSION

SL is effective even for R-PDAC. The prognosis of CY1 patients converted to CY-negative is expected to be similar to that of CY0 patients.

Predictive impacts of peritoneal washing cytology for surgical resection-intended pancreatic cancer cases: Establishment of planned staging laparoscopy criteria

BACKGROUND

Staging laparoscopy (SL) has been advocated for pancreatic cancer, mainly to evaluate the peritoneal washing cytology (CY) status, which seems to impact the prognosis of pancreatic cancer. To establish an optimal treatment strategy for CY positive (CY+) pancreatic cancer cases, real-world clinical data about CY status-depending surgical outcomes should be accumulated.

METHODS

Peritoneal washing samples were collected from 183 consecutive patients who could be classified as either resectable or borderline resectable (BR) pancreatic cancer between January 2012 and December 2020. Correlations between the CY status and other clinicopathological parameters with the recurrence patterns and survival outcomes were examined. In addition, we analyzed several risk factors for the CY+ status and attempted to identify the patient population that may benefit most from SL.

RESULTS

A total of 24 of the 183 patients were CY+. Peritoneal recurrence occurred more frequently in CY+ cases than in CY- cases (29% vs. 6%, p < .001) and median survival time after surgery was significantly shorter in CY+ cases than in CY- cases (28.5 months vs. 67.5 months; p < .001). In detail, almost all CY+ patients among curative resection-intended cases had either elevated preoperative serum CA19-9 levels (≥250 U/mL) or DUPAN-2 levels (≥150 U/mL). Significant predictive factors of CY positivity were BR status (p = .028) and serum CA19-9 level exceeding 250 U/mL (p = .008).

CONCLUSION

CY status was identified as an independent prognostic factor, and SL examination should be recommended, especially for patients with risk factors for CY positivity, such as BR cancer and elevated serum CA19-9 levels.

Laparoscopic distal pancreatectomy for pancreatic tail cancer in a 100-year-old patient

We present the case of a 100-year-old man with no specific symptoms. Computed tomography (CT) revealed a 34 mm tumor in the pancreatic tail, which was diagnosed as pancreatic cancer by biopsy. CT and magnetic resonance imaging showed that the tumor was resectable, and there were no noncurative factors on staging laparoscopy (cT3N0M0: cStage IIA). His performance status was good, and hypertension was the only comorbidity. A cardiologist, respiratory physician, and anesthesiologist examined the patient and determined that his condition was suitable for surgery. His postoperative predicted mortality rate was 0.9% using the American College of Surgeons risk calculator. We administered synbiotics and nutrients before surgery and introduced preoperative rehabilitation to improve his activities of daily living (ADL) as well as respiratory training to prevent postoperative pneumonia. Regarding the invasiveness of the surgery, we performed laparoscopic distal pancreatectomy with D1 lymphadenectomy. The patient was discharged on postoperative day 17, without any major complications. When performing pancreatectomy in older adults, it is important to fully assess preoperative tolerance and perioperative risk and prevent worsening of ADL by introducing nutritional therapy and rehabilitation.

LC-1000 flow cytometry system complements intraoperative peritoneal cytology for pancreatic and biliary tract cancer

BACKGROUND

The exfoliative cell analyzer, LC-1000, is medical device that utilizes the principles of flow cytometry, and might provide digital diagnostic information for cytology using a different approach from conventional cytomorphology. In this study, wae examined the usefulness of the LC-1000 as a diagnostic support system for intraoperative peritoneal lavage cytology and its prognostic impact for pancreatic (PC) and biliary tract cancer (BTC).

METHODS

Patients with PC and BTC who underwent surgical treatment were included. First, we identified useful indicators of LC-1000 and established cutoff values to discriminate positive cytology. Next, we verified the validity of these cutoff values.

RESULTS

In the test set (n = 48), of the LC-1000 indicators examined, only MR-CPIx was significantly different between the negative and positive cytology groups, yielding a cutoff value of 0.86. In the validation set (n = 52), the sensitivity, specificity, positive and negative predictive value of the LC-1000 for cytology results was 1.0, 0.49, 0.11 and 1.0, respectively. In patients who had undergone radical resection, recurrence-free survival rate was significantly higher in the LC-1000 negative group than in the positive group in PC, but not in BTC.

CONCLUSION

The LC-1000 was useful as digital support system for peritoneal cytology, and it might have potential as a prognostic factor for PC.

Failure of peritoneal lavage to prevent operative site infection and peritoneal tumor recurrence in pancreatic surgery

BACKGROUND

Although intraoperative peritoneal lavage often is performed routinely with the aim of reducing peritoneal contamination, evidence of lavage benefit in elective pancreatic surgery is limited.

METHODS

We retrospectively classified patients who had undergone pancreatic surgery to groups given or not given peritoneal lavage, then comparing clinical results. This saline lavage was performed at the end of the operation. The primary endpoint was rate of surgical site infection. Frequency of peritoneal recurrence also was evaluated.

RESULTS

Among all 104 patients in the study, incidence of infectious complications in the lavage group (n = 65) was significantly higher than in the non-lavage group (n = 39; 35% vs. 15%, P = 0.041), while incidences of postoperative complications overall and surgical site infection did not differ between lavage (80% and 26%) and non-lavage groups (67% and 10%, P = 0.162 and 0.076, respectively). Among 63 patients undergoing pancratoduodenectomy, frequencies of positive bacterial cultures of drainage fluids on postoperative days 1 and 3 were greater in the non-lavage group (P < 0.001 and P = 0.012), but surgical site infection was significantly more frequent in the lavage group (P = 0.043). Among patients with pancreatic and biliary cancers, lavage did not affect frequency of peritoneal recurrence.

CONCLUSION

Intraoperative lavage did not prevent surgical site infection or peritoneal recurrence of pancreatobiliary cancer.

Long-term adjuvant chemotherapy after resection for pancreatic cancer patients with positive peritoneal lavage cytology

PURPOSE

The significance of resection for pancreatic cancer with positive peritoneal lavage cytology (CY +) remains controversial, and the lack of evidence concerning adjuvant chemotherapy (AC) in these patients remains an issue. The aim of the present study was to investigate the prognostic impacts of AC and its duration on the survival outcome in patients with CY + pancreatic cancer.

METHODS

A total of 482 patients with pancreatic cancer who underwent pancreatectomy between 2006 and 2017 were retrospectively analyzed. The overall survival (OS) was compared among the patients with CY + tumors according to the duration of AC.

RESULTS

Among the resected patients, 37 (7.7%) had CY + tumors: 13 received AC for > 6 months, 15 received AC for ≤ 6 months and 9 did not receive AC. The OS of 13 patients with resected CY + tumors who received AC for > 6 months was comparable to that of 445 patients with resected CY- tumors (median survival time 43.0 vs. 33.6 months, P = 0.791), and was significantly better than that of 15 patients with resected CY + tumors who received AC for ≤ 6 months (vs. 16.6 months, P = 0.017). The duration of AC (> 6 months) was an independent prognostic factor in patients with resected CY + tumors (hazard ratio 3.29, P = 0.005).

CONCLUSION

Long-term AC (> 6 months) may improve postoperative survival in pancreatic cancer patients with CY + tumors.

Increased incidence of positive peritoneal lavage cytology early after fine needle aspiration in patients with pancreatic ducal adenocarcinoma

BACKGROUND

The influence of fine needle aspiration (FNA) on peritoneal lavage cytology (CY) in pancreatic ductal adenocarcinoma (PDAC) is unknown.

METHODS

We retrospectively analyzed 29 patients with resectable left-sided PDAC undergoing FNA prior to CY examination. We assessed clinical factors related to CY+, scored the tumor diameter (<20 mm = 0, ≥20 mm = 1) and examination interval between FNA and CY (>18 days = 0, ≤18 days = 1), and investigated the probability of CY + by the sum of each score (0-2).

RESULTS

The probability of CY+ was 31%. The CY + group had larger tumors and shorter examination intervals than the CY- group. The CY + probability was 75%, 15%, and 13% for a score of 2, 1, and 0, respectively (P = 0.011).

CONCLUSION

A short interval between FNA and CY examination for a large tumor may be a risk factor for CY+ in patients with left-sided PDAC.

Gastric intramural metastasis caused by needle tract seeding after preoperative fine needle aspiration for pancreatic body cancer subsequently resected by total pancreatectomy: a case report and literature review

BACKGROUND

Recently, there has been an increase in the number of reports of needle tract seeding (NTS) of tumor cells after a biopsy as one of the adverse events related to endoscopic ultrasonography-guided fine needle aspiration (EUS-FNA). In most of the previously reported cases of NTS in pancreatic cancer, distal pancreatectomy was performed as the initial surgery, following which metachronous metastasis was discovered in the gastric wall, whose localization matched the puncture route of the EUS-FNA. We report a case of early metastasis from pancreatic cancer in the gastric wall, which was postulated to be caused by NTS. Our patient underwent a total pancreatectomy (TP), and the NTS was resected synchronously.

CASE PRESENTATION

A 70-year-old woman with a diagnosis of pancreatic head-body-tail cancer presented to our department for surgery. Transgastric EUS-FNA and biopsy established the histological diagnosis in her case. We administered neoadjuvant chemotherapy (NAC) to the patient and performed a TP. Histopathological and immunohistochemical examination subsequently confirmed the diagnosis of pT3N1aM1 pancreatic adenocarcinoma and its gastric metastasis, which was caused by NTS. It is postulated that the tumor cells of NTS had progressed to develop the metastatic lesion in the gastric wall during the NAC period. This was also resected during the initial surgery. The patient developed an early postoperative recurrence in the peritoneum 8 months after the surgery.

CONCLUSION

In pancreatic head cancer cases, the puncture route is often included in the resection area of radical surgery, and NTS is seldom considered as a potential clinical problem. However, NTS can progress rapidly and may be associated with early recurrence of malignancy. Therefore, when transgastrointestinal puncture is performed for the diagnosis of pancreatic cancer, the treatment strategy should be established considering the potential development of NTS.

Clinical Implications of FDG-PET in Pancreatic Ductal Adenocarcinoma Patients Treated with Neoadjuvant Therapy

PURPOSE

To evaluate the clinical significance of ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography in patients with pancreatic ductal adenocarcinoma who underwent neoadjuvant therapy.

METHODS

Among 285 consecutive patients who underwent pancreatic resection for pancreatic ductal adenocarcinoma between 2015 and 2021, 86 who underwent preoperative ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography after completion of neoadjuvant treatment were reviewed. Among preoperative factors, including post-treatment maximum standardized uptake value, predictors of early recurrence and poor prognosis were identified using multivariate analysis for decision making in surgery.

RESULTS

Nineteen (22%) patients with pancreatic ductal adenocarcinoma demonstrated high maximum standardized uptake (≥ 4.5). High post-treatment maximum standardized uptake (≥ 4.5) predicted early recurrence within 6 months after surgery and correlated with shorter recurrence-free survival. Elevated post-treatment CA19-9 level (> 37 U/ml) and maximum standardized uptake ≥ 4.5 were independent prognostic factors. Post-treatment, a high maximum standardized uptake value indicated a poorer prognosis than a low maximum standardized uptake value in both patients with elevated CA19-9 and normal CA19-9 levels. The median overall survival in patients with elevated post-treatment CA19-9 and high maximum standardized uptake was only 17 months; 67% experienced early recurrence. Dynamic changes in maximum standardized uptake during neoadjuvant therapy were correlated with pathological response to neoadjuvant therapy, but not with radiological response or change in CA19-9 level.

CONCLUSIONS

Post-treatment assessment using maximum standardized uptake value is useful for stratifying patients with pancreatic ductal adenocarcinoma who will benefit from surgery. Instead of subsequent curative resection, additional neoadjuvant therapy should be considered in patients with a persistently high maximum standardized uptake value.

Survival impact of occult liver metastasis and peritoneal dissemination compared with radiologically defined distant organ metastasis in pancreatic ductal adenocarcinoma

BACKGROUND

Characteristics and prognoses of patients with occult metastases (OM) of pancreatic ductal adenocarcinoma (PDAC) compared with radiologically defined metastases (RM) have been rarely reported.

OBJECTIVE

We aimed to clarify the prognosis of OM compared with RM and to establish a treatment strategy for PDAC patients with OM.

METHODS

This single-institution, retrospective study evaluated patients with unresectable PDAC between 2008 and 2018. OM was defined as abdominal metastasis that was detected by staging laparoscopy or open laparotomy but not in the initial assessment of radiological images.

RESULTS

OM and RM were identified in 135 and 112 patients, respectively. Eastern Cooperative Oncology Group Performance Status (ECOG PS), neutrophil to lymphocyte ratio (NLR), tumor diameter, and rate of local unresectability were significantly lower in the OM group. Median overall survival (OS) of OM was significantly better than that of RM (13.0 vs 8.9 months, p < 0.001). In multivariate analysis of OS, ECOG PS ≥ 1 (HR 1.64, p = 0.009), NLR ≥5 (HR 1.97, p = 0.004), carbohydrate antigen (CA) 19-9 ≥1000 (HR 1.68, p = 0.001), tumor diameter ≥40 mm (HR 1.40, p = 0.027), conversion surgery (HR 0.12, p < 0.001), and multiple lines of chemotherapy (HR 0.38, p < 0.001) were independent predictors. However, type of metastasis (OM vs RM) not an independent predictor (HR 1.10, p = 0.590).

CONCLUSION

The prognosis of PDAC with OM was relatively better than that with RM, but general and nutritional statuses, primary tumor size and CA19-9, conversion surgery and multiple lines of chemotherapy were independent predictors but not tumor burden.

Clinical significance of immunocytochemical staining for peritoneal lavage cytology in pancreatic cancer

BACKGROUND

Peritoneal lavage cytology for pancreatic ductal adenocarcinoma is conducted with both an intraoperative rapid diagnosis by Papanicolaou staining (cytology-rapid) and a final diagnosis by immunocytochemical staining at a later date (cytology-final) in our hospital. However, the clinical significance of cytology-final has not yet been elucidated.

METHODS

A total of 675 pancreatic ductal adenocarcinoma patients who underwent pancreatectomy and cytology between 2002 and 2018 were retrospectively reviewed. Diagnostic results of cytology-rapid and cytology-final and survival outcomes were analyzed.

RESULTS

A total of 43 patients (6.4%) were diagnosed as cytology-rapid (+), and all of them were ultimately diagnosed as cytology-final (+). Among the 632 patients with cytology-rapid (-), 19 (3.0%) were eventually diagnosed as cytology-final (+). The overall survival of patients with cytology-rapid (+) and that of patients with cytology-rapid (-) did not differ to a statistically significant extent (median survival time 26.4 vs 32.9 months; P = .106). In contrast, the overall survival of patients who were diagnosed as a false-negative result by cytology-rapid was significantly worse than that of patients diagnosed as a true negative (18.7 vs 34.8 months; P = .031). The overall survival of patients with cytology-final (+) was significantly worse than that of patients with cytology-final (-) (23.6 vs 34.8 months; P = .012). A multivariate analysis showed that cytology-final (+) was an independent prognostic factor for the OS (hazard ratio = 1.43; P = .049), whereas cytology-rapid (+) was not.

CONCLUSION

Immunocytochemical staining may be a useful complement to a diagnosis of cytology by conventional Papanicolaou staining in pancreatic ductal adenocarcinoma patients.

Levels of tumor markers CEA/CA 19-9 in serum and peritoneal lavage predict postoperative recurrence in patients with pancreatic cancer

Aim

This study aimed to clarify the usefulness of tumor markers from peritoneal lavage in selecting patients with a high risk of recurrence and predicting site-specific recurrence in patients with pancreatic cancer.

Methods

The levels of serum carcinoembryonic antigen (CEA) and carbohydrate antigen (CA) 19-9 (sCEA/sCA 19-9) and paired peritoneal lavage CEA and CA 19-9 (pCEA/pCA 19-9) were measured in 90 patients with pancreatic cancer who underwent surgery. Using the cutoff values determined by maximally selected rank statistics for disease-free survival (DFS), the risk of recurrence and its patterns were evaluated in combination with different markers and different test specimens.

Results

In univariate and multivariate analysis, an elevated pCA 19-9 level (>1.3 U/mL) was an independent prognostic marker for both DFS (hazard ratio [HR], 2.391; P = .018) and overall survival (HR, 3.194; P = .033). Combination analyses contributed to further stratification of a very high risk of recurrence. Of the 58 patients with resectable pancreatic cancer who underwent curative resection, elevated pCA19-9 was also associated with inferior DFS and overall survival (OS). Patients with elevated pCA 19-9 levels were more likely to have an earlier onset of peritoneal recurrence than those with normal pCA 19-9 levels (P = .048, Gehan-Breslow-Wilcoxon test).

Conclusion

pCA 19-9 is a reliable marker for predicting postoperative recurrence in patients with pancreatic cancer after surgery. Further risk stratification can be achieved by using combination assays. The combination of pCA 19-9 and sCA19-9 also serves as a predictor of recurrence site-specific recurrence.

Should Positive Cytology Revealed by Intraoperative Lavage Preclude Radical Resection in Resectable Pancreatic Cancer?: A Systemic Review and Meta-analysis

OBJECTIVES

The aims of this review were to determine whether positive peritoneal lavage cytology (CY+) precludes radical resection in pancreatic cancer and to propose prospections for future studies.

METHODS

MEDLINE, Embase, and Cochrane Central were searched for related articles. Dichotomous variables and survival outcomes were analyzed with the estimation of odds ratio and hazards ratio (HR), respectively.

RESULTS

A total of 4905 patients were included, of which 7.8% were CY+. Positive peritoneal lavage cytology was correlated with poor overall survival (univariate survival analysis [HR, 2.35; P < 0.00001]; multivariate analysis [HR, 1.62; P < 0.00001]), poor recurrence-free survival (univariate survival analysis [HR, 2.50; P < 0.00001]; multivariate analysis [HR, 1.84; P < 0.00001]), and higher initial peritoneal recurrence rate (odds ratio, 5.49; P < 0.00001).

CONCLUSIONS

Although CY+ predicts poor prognosis and a higher risk of peritoneal metastasis after curative resection, it is not sufficient to preclude curative resection based on the current evidence, and high-quality trials should be conducted to assess the prognostic impact of operation among resectable CY+ patients. In addition, more sensitive and accurate methods to detect peritoneal exfoliated tumor cells and more effective comprehensive treatment for resectable CY+ pancreatic cancer patients are clearly warranted.

Prognostic Significance of Intraoperative Peritoneal Lavage Cytology in Patients with Pancreatic Ductal Adenocarcinoma: A Single-Center Experience and Systematic Review of the Literature

BACKGROUND

The prognostic significance of peritoneal lavage cytology (PLC) in patients with pancreatic ductal adenocarcinoma (PDAC) remains controversial. The purpose of this study was to evaluate the prognostic impact of PLC status in PDAC patients.

METHODS

Patients intending to undergo resection for PDAC between 2007 and 2020 were included. Survival was compared among patients who underwent resection with negative or positive PLC status and those who did not undergo resection. Univariable and multivariable analyses were conducted to evaluate the prognostic impact of positive PLC status. A systematic literature review was performed to evaluate the correlation between prognosis and the positive PLC rate.

RESULTS

A total of 480 patients formed the study cohort and were divided as follows: 438 in the negative PLC group, 18 in the positive PLC group, and 24 in the no resection group. Although the median survival time significantly differed between the negative and positive PLC groups (35.7 vs. 13.6 months, P < 0.001), it did not significantly differ between the positive PLC and no resection groups (13.6 vs. 12.2 months, P = 0.605). Multivariable analyses demonstrated that positive PLC status (hazard ratio = 3.54, 95% confidence interval = 1.97-6.38, P < 0.001) was the strongest poor prognostic factor. Based on statistical analyses for the systematic review, the prognostic impact of positive PLC status weakened significantly as the institutional positive PLC rate increased (P = 0.044).

CONCLUSIONS

Resection did not improve the prognosis of patients with positive PLC status in our cohort. The institutional positive PLC rate may be a good reference for surgical indication in these patients.

Synopsis of a clinical practice guideline for pancreatic ductal adenocarcinoma with peritoneal dissemination in Japan; Japan Peritoneal Malignancy Study Group

Patients with pancreatic ductal adenocarcinoma (PDAC) with peritoneal dissemination have a dismal prognosis because discontinuation of systemic chemotherapy is required for massive ascites or poor performance status. The natural history, diagnosis and treatment of PDAC with peritoneal dissemination have not been fully investigated. We systematically reviewed published information on the clinical diagnosis and treatment of PDAC with peritoneal dissemination using the PubMed database (2000-2020) and provided recommendations in response to clinical questions. This guideline was created according to the "Minds Clinical Practice Guideline Development Guide 2017". The literature quality and body of evidence were evaluated with the GRADE System and classified into four levels ("strong", "medium", "weak", "very weak"). The strength of each final recommendation was decided by a vote of committee members based on the GRADE Grid method. These guidelines address three subjects: diagnostic, chemotherapeutic, and surgical approaches. They include nine clinical questions and statements with recommendation strengths, evidence levels, and agreement rates, in addition to one "column". This is the English synopsis of the 2021 Japanese clinical practice guideline for PDAC with peritoneal dissemination. It summarizes the clinical evidence for the diagnosis and treatment of PDAC with peritoneal dissemination and provides future perspectives.

Preoperative risk factors for positivity of peritoneal lavage cytology in patients with pancreatic ductal adenocarcinoma in the era of neoadjuvant therapy

BACKGROUND

The preoperative risk factors for positive peritoneal lavage cytology (CY) are unknown, especially in patients who received neoadjuvant therapy. In addition, the optimal indications for staging laparoscopy (SL) are still unclear. The aim of this study was to investigate the preoperative risk factors of CY positivity in patients with pancreatic ductal adenocarcinoma (PDAC) treated with surgical resection and to determine the optimal indications for SL.

METHODS

We retrospectively analyzed 493 patients with PDAC, including 356 treated with upfront surgery and 137 treated with neoadjuvant chemotherapy (NAC). The preoperative risk factor for CY positivity was investigated along with stratification according to NAC.

RESULTS

Among the 493 patients, 36 (7.3%) were CY-positive. The CY-positive frequency in patients who received and did not receive NAC was 9 (6.6%) and 27 (7.6%), respectively. In the multivariate analyses, no independent preoperative predictive factor was found in patients who received NAC, whereas body and tail PDAC were identified as an independent risk factor for CY positivity in patients who did not receive NAC.

CONCLUSIONS

The preoperative risk factors of CY-positive PDAC are body and tail PDAC in 356 patients who did not receive NAC. However, there is no useful predictive factor for CY positivity in patients treated with NAC. Based on these results, it was difficult to determine the optimal indication for SL especially in NAC cases.

Intraoperative Cytologic Sampling for Resected Pancreatic and Periampullary Adenocarcinoma with Implications for Locoregional Recurrence-Free Survival

BACKGROUND

We hypothesized that pancreatic and periampullary adenocarcinoma recurrence after surgical resection may be affected by the shedding of malignant epithelial cells during surgical dissection and that this may have implications for disease recurrence and survival.

STUDY DESIGN

In this ongoing, investigator-initiated prospective randomized controlled trial, patients with pancreatic and periampullary adenocarcinoma were randomized intraoperatively, postresection into 3 study arms: peritoneal lavage using 10 L normal saline or distilled water, or control group with no lavage. Peritoneal fluid was sampled for cytologic analysis (cytospin, cellblock, immunohistochemistry-Ber-EP4 antibody) at 4 stages: (1) abdominal entry pre-dissection, (2) resection bed after tumor extirpation, (3) ex vivo resected specimen, and (4) resection bed postlavage.

RESULTS

Between April 2016 and May 2018, 193 patients who underwent randomization for the study also underwent the described cytologic sampling. Of these, 167 patients (86.5%) were ultimately found to have pancreatic or periampullary adenocarcinoma. Before dissection (1) on cytospin analysis, 4.9% were positive, which rose to 10.2% intraoperatively (2), 16.7% ex vivo (3), and decreased to 4.3% (4) after lavage. Lymph node metastasis, margin involvement, and perineural invasion did not correlate with locoregional recurrence (LR). Tumor cells in the ex vivo cytospin (3) correlated with LR (odds ratio 3.8 [95% CI 1.6 to 9.2], p = 0.005) and LR disease-free survival (p = 0.007). Cox regression analysis revealed ex vivo cytospin positivity to be strongly associated with poorer LR disease-free survival (hazard ratio 2.26 [95% CI 1.16 to 4.42], p = 0.017).

CONCLUSIONS

Cytologic sampling from ex vivo specimen irrigation after surgical resection of pancreatic and periampullary adenocarcinoma may have implications for LR, survival, and treatment, suggesting a possible cancer cell shedding phenotype.

Impact of Tumor-Derived DNA Testing in Peritoneal Lavage of Pancreatic Cancer Patients with and Without Occult Intra-Abdominal Metastases

BACKGROUND

The fractional abundance of tumor-derived DNA in body fluids depends on the metastatic sites and the degree of expansion. We aimed to assess the clinical significance of tumor-derived DNA testing in the peritoneal lavage of patients with pancreatic cancer.

METHODS

The prevalence and abundance of tumor-derived DNA was assessed in 204 subjects with ascites by peritoneal lavage (AS) and the evaluable paired plasma (PL) from 149 pancreatic cancer patients undergoing abdominal exploration. Genetic profiles were evaluated by next-generation sequencing, and prognostic impact was assessed using Cox proportional hazard models.

RESULTS

Of 204 subjects, AS samples from patients with peritoneal dissemination (PER+) and positive cytology (CY+) showed significantly higher prevalence and abundance of tumor-derived DNA than those with negative counterparts. Tumor-derived DNA prevalence and abundance in AS were more likely to be higher than in paired PL in a subgroup of patients with PER+ and CY+, respectively. Next-generation sequencing revealed concordant or discrepant mutational patterns between the AS and PL samples. Multivariate analysis showed that both tumor-derived DNA in AS (hazard ratio [HR] 3.940, p = 0.009) and PL (HR 2.936, p = 0.026) were independently associated with poor survival in treatment-naïve patients. In patients who underwent resection, tumor-derived DNA positivity in the AS was more predictive of early recurrence than in PL.

CONCLUSIONS

Tumor-derived DNA in AS can serve as characterizing the genetic profiles of tumor cells attributable to the development of PER+ and predicting the minimal residual disease and early recurrence in patients with pancreatic cancer.

Prognostic Value of Peritoneal Lavage Cytology in Patients with Pancreatic Ductal Adenocarcinoma Stratified by the Resectability Status

BACKGROUND

The prognostic value of peritoneal lavage cytology (CY) for pancreatic ductal adenocarcinoma (PDAC) remains controversial. We assessed the prognostic impact of CY status stratified by resectability in PDAC patients treated with surgical resection.

METHODS

Clinical data from 440 patients with PDAC who underwent surgical resection were retrospectively analyzed to examine the association of CY status with clinicopathological factors and survival.

RESULTS

Positive CY status (CY+) was found in 30 patients (7%). These patients had significantly worse overall survival in both the resectable (R) (P = 0.002) and borderline resectable (BR) (P < 0.001) groups. The median survival time of CY+ patients in the R and BR groups was 25.6 and 6.7 months, respectively. Multivariate analysis revealed that CY+ was an independent prognostic factor in the BR group (P < 0.001) but not in the R group (P = 0.08). In the R group, CY+ patients who received adjuvant chemotherapy had significantly longer overall survival than those without adjuvant chemotherapy (34.3 vs. 9.8 months, respectively; P < 0.001).

CONCLUSIONS

The prognosis of CY+ patients in the BR group was extremely poor. In the R group, surgical resection combined with adjuvant chemotherapy may improve the prognosis of CY+ patients.

A simple risk score for detecting radiological occult metastasis in patients with resectable or borderline resectable pancreatic ductal adenocarcinoma

BACKGROUND

We advocated carbohydrate antigen (CA) 19-9 ≥ 150 U/mL and tumor size ≥30 mm as "high-risk markers" for predicting unresectability among patients with radiologically resectable (R) or borderline resectable (BR) pancreatic ductal adenocarcinoma (PDAC). The main aim is to establish a risk scoring system for occult abdominal metastasis (OAM) in R/BR PDAC.

METHODS

Predictors of OAM were investigated retrospectively in an experiment cohort from 2006 to 2018. The proposed risk scoring system was validated in another cohort from 2019 to 2020.

RESULTS

Five hundred and thirteen eligible patients were divided into the experimental (405 patients; OAM, 22%) and validation cohorts (108 patients). Multivariate analysis identified tumor location of body/tail (odds ratio [OR] 4.45, P < .0001) and "high-risk markers" (OR 2.07, P = .011) as independent predictors of OAM. A scoring system consisting of body/tail (yes: 1, no: 0) and "high-risk markers" (yes: 1, no: 0) was constructed. In the validation cohort, when staging laparoscopy (SL) was performed for patients with scores 1/2, the eligibility for SL, sensitivity, and negative predictive value of OAM were 55%, 91%, and 96%, respectively.

CONCLUSIONS

Tumor location of body/tail and "high-risk markers" were independent predictors of OAM, composing our simple and reproducible risk scoring system.

Circulating tumor DNA as a predictive marker for occult metastases in pancreatic cancer patients with radiographically non-metastatic disease

PURPOSE

To elucidate the effectiveness of circulating tumor DNA (ctDNA) for predicting occult metastases in patients with pancreatic cancer without apparent metastases.

METHODS

Circulating tumor DNA was obtained from plasma samples of 165 patients with pancreatic cancer and analyzed using droplet digital PCR. The prevalence and allele frequencies of ctDNA were compared across different patterns and degrees of metastatic spread.

RESULTS

Of the 142 patients without apparent metastases who underwent abdominal exploration, 39 (27.5%) harbored occult metastases including positive peritoneal lavage cytology. The prevalence of ctDNA was significantly higher in patients with occult metastases than in those without (41.0% vs 14.6%, P = .001). A markedly high prevalence of ctDNA was observed in patients with radiographically visible metastases (78.3%). ctDNA was found to be an independent predictor of the presence of occult metastases (odds ratio: 3.113, P = .039), and its diagnostic performance in combination with tumor markers had a sensitivity of 66.7% and a specificity of 81.6%. In 62 treatment-naïve patients without metastases, multivariate analysis identified the presence of ctDNA as an independent prognostic factor (hazard ratio: 6.311, P = .001).

CONCLUSION

Circulating tumor DNA can help predict the presence of occult metastases in pancreatic cancer patients with radiographically non-metastatic disease.

Achieving 'Marginal Gains' to Optimise Outcomes in Resectable Pancreatic Cancer

Simple Summary

Improving outcomes in pancreatic cancer is achievable through the accumulation of marginal gains. There exists evidence of variation and undertreatment in many areas of the care pathway. By fully realising the existing opportunities, there is the potential for immediate improvements in outcomes and quality of life.

Abstract

Improving outcomes among patients with resectable pancreatic cancer is one of the greatest challenges of modern medicine. Major improvements in survival will result from the development of novel therapies. However, optimising existing pathways, so that patients realise benefits of already proven treatments, presents a clear opportunity to improve outcomes in the short term. This narrative review will focus on treatments and interventions where there is a clear evidence base to improve outcomes in pancreatic cancer, and where there is also evidence of variation and under-treatment. Avoidance of preoperative biliary drainage, treatment of pancreatic exocrine insufficiency, prehabiliation and enhanced recovery after surgery, reducing perioperative complications, optimising opportunities for elderly patients to receive therapy, optimising adjuvant chemotherapy and regular surveillance after surgery are some of the strategies discussed. Each treatment or pathway change represents an opportunity for marginal gain. Accumulation of marginal gains can result in considerable benefit to patients. Given that these interventions already have evidence base, they can be realised quickly and economically.

Essential updates 2019/2020: Multimodal treatment of localized pancreatic adenocarcinoma: Current topics and updates in survival outcomes and prognostic factors

Overall survival of patients with localized pancreatic ductal adenocarcinoma (PDAC) is extremely poor. Therefore, the establishment of multimodal treatment strategies is indispensable for PDAC patients because surgical treatment alone could not contribute to the improvement of survival. In this review article, we focus on the current topics and advancement of the treatments for localized PDAC including resectable, borderline resectable, and locally advanced PDAC in accordance with the articles mainly published from 2019 to 2020. Reviewing the articles, the recent progress of multimodal treatments notably improves the prognosis of patients with localized PDAC. For resectable PDAC, neoadjuvant chemo or chemoradiation therapy, rather than upfront surgery, plays a key role, especially in patients with a large tumor, poor performance status, high tumor marker levels, peripancreatic lymph nodes metastasis, or neural invasion suspected on preoperative imaging. For borderline resectable PDAC, neoadjuvant treatments followed by surgery is a desirable approach, and maintenance of immunonutritional status during the treatments are also important. For locally advanced disease, conversion surgery has a central role in improving a survival outcome; however, its indication should be standardized.

Preceding Systemic Chemotherapy for Patients with Pancreatic Ductal Adenocarcinoma with Positive Peritoneal Cytology Provides Survival Benefit Compared with Up-Front Surgery

BACKGROUND

The significance of surgical resection in pancreatic ductal adenocarcinoma (PDAC) with positive peritoneal cytology (PPC) is controversial. This study aimed to evaluate whether preceding chemotherapy could be beneficial for patients with PDAC with PPC.

METHODS

Between 2017 and 2019, 34 consecutive PDAC patients diagnosed with PPC without distant metastasis were retrospectively reviewed. Twenty-three patients did not receive neoadjuvant treatment (NAT) and 11 received NAT. All patients received systemic chemotherapy after PPC was confirmed, and they underwent surgical resection if PPC turned negative. The treatment course, ratio of conversion surgery (CS), and prognosis were evaluated. Moreover, the prognosis of PPC patients who underwent up-front surgery without NAT between 2003 and 2016 was analyzed as a comparative cohort.

RESULTS

The median survival time (MST) of the patients without NAT was 31.4 months. CS was performed in 52.2% of the patients. Patients who underwent CS had better prognoses than those who did not undergo CS (p = 0.005). The CS rate was significantly higher in resectable PDAC (78.5%) than in borderline/unresectable PDAC (11.1%) (p = 0.002). The prognosis of patients with resectable PDAC was improved with preceding chemotherapy compared with up-front surgery (MST 13.0 months; p = 0.016). After NAT, the CS rate was low (27.3%), and the MST was only 14.1 months.

CONCLUSIONS

As an initial treatment for PDAC patients with PPC, chemotherapy may lead to a favorable prognosis. Especially, resectable PDAC is associated with a greater chance of improved prognosis. Future studies are required to ascertain whether up-front surgery or preceding chemotherapy should be performed for these patients.

The prognostic impact of peritoneal washing cytology for otherwise resectable extrahepatic cholangiocarcinoma patients

The clinical importance of peritoneal washing cytology (PWC) for cholangiocarcinoma patients remains unclear. The clinical data of 137 extrahepatic cholangiocarcinoma patients who received PWC and curative surgery were retrospectively analyzed. Among the 137 patients analyzed, five (3.6%) had positive PWC, and 132 (96.4%) had negative PWC. The median survival time in patients with negative PWC was 6.45 years, and the overall 1-, 2-, and 5-year survival rates were 86.5%, 75.3%, and 51.6%, respectively. The median survival time in patients with positive PWC was 2.56 years, and the overall 1-, 2-, and 5-year survival rates were 60.0%, 60.0%, and 40.0%, respectively. A multivariate analysis revealed that positive lymph node metastasis (P < 0.001), positive perineural invasion (P = 0.014) and no use of adjuvant chemotherapy (P < 0.001), but not positive PWC were independently associated with a worse overall survival. In conclusion, surgery and subsequent chemotherapy might be a therapeutic option for cholangiocarcinoma patients with positive PWC.

MicroRNA-593-3p Expression in Peritoneal Lavage Fluid as a Prognostic Marker for Pancreatic Cancer Patients Undergoing Staging Laparoscopy

BACKGROUND

Some presumed resectable pancreatic cancer patients harbor radiographically occult metastases that are incidentally identified at the time of abdominal exploration. This study aims to identify novel diagnostic or predictive microRNA (miRNA) markers for subclinical peritoneal dissemination in patients with pancreatic cancer undergoing abdominal exploration.

METHODS

Peritoneal lavage fluid samples were harvested from 74 patients with pancreatic cancer at the time of staging laparoscopy. Microarray analysis was performed using peritoneal lavage fluids with positive and negative cytology. Candidate microRNA expression was quantified and validated by droplet-digital PCR assays.

RESULTS

In the miRNA array analysis, miR-593-3p showed significant upregulation in peritoneal lavage fluids with positive cytology. Of the 74 patients validated, peritoneal lavage fluids with positive cytology had significantly higher expression of miR-593-3p than those with negative cytology (P < 0.001). Even in cases with no peritoneal dissemination and negative cytology, multivariate analysis revealed that elevated miR-593-3p expression was significantly correlated with worse overall survival than those with low expression (hazard ratio: 3.474, P = 0.042). Of the 48 patients who underwent pancreatectomy, multivariate analysis also demonstrated that higher expression of miR-593-3p in peritoneal lavage was the only significant poor prognostic marker influencing both overall survival (hazard ratio: 23.38, P = 0.005) and recurrence-free survival (hazard ratio: 5.700, P = 0.002).

CONCLUSIONS

Elevated miR-593-3p expression in peritoneal lavage suggests the presence of subclinical micrometastasis even in cases with localized pancreatic cancer, and miR-593-3p could be a useful prognostic predictor for pancreatic cancer patients undergoing staging laparoscopy.

Predicting positive peritoneal cytology in pancreatic cancer

INTRODUCTION

Positive cytology from peritoneal washings obtained prior to potential resection of pancreatic cancer is associated with grim prognosis, equivalent to M1 disease. We examine our experience with pancreatic cancer patients who underwent pre-resection lavage in an attempt to predict who would have malignant cells on peritoneal cytology.

METHODS

We conducted a retrospective review of patients undergoing pancreatectomy for pancreatic adenocarcinoma at a tertiary care institution from 1995 to 2019 and had pre-resection lavage performed. Demographic and clinicopathologic data were collected. Logistic regression models were used to identify predictors of positive cytology.

RESULTS

Three hundred ninety-nine patients underwent pancreatic resection and had lavage performed. Forty-three (10.8%) had positive peritoneal cytology. Those with positive cytology had higher median Ca19-9 value than those with negative cytology at diagnosis (368.5 vs 200 U/mL, p = 0.007) and after neoadjuvant therapy (100.3 vs 43 U/mL, p = 0.013). After controlling for preoperative therapy received, an initial Ca19-9 greater than 1220 U/mL (OR 2.72, 95% CI 1.07-6.89, p = 0.035), locally advanced disease (OR 4.86, 95% CI 1.31-18.09, p = 0.018), and BMI ≥ 25 kg/m² (OR 2.67, 95% CI 1.04-6.97, p = 0.042) were associated with positive cytology in multivariate logistic regression model. The associated ROC curve had an AUC of 0.7507, suggesting adequate discrimination of those with positive peritoneal cytology.

CONCLUSION

Diagnostic laparoscopy remains an important adjunct to the workup, diagnosis, and staging of pancreatic adenocarcinoma. Patients with locally advanced disease, significantly elevated serum Ca19-9 at diagnosis, and BMI ≥ 25 kg/m² may be at higher risk for positive peritoneal cytology, regardless of whether neoadjuvant therapy is administered.

Age-Related Differences in the Prognosis of Pancreatic Cancer According to Perioperative Systemic Therapy

OBJECTIVES

In this study, we retrospectively assessed the feasibility and prognostic efficacy of perioperative chemo(radio)therapy for pancreatic cancer (PC) patients according to age.

METHODS

A total of 556 consecutive patients who underwent curative-intent pancreatectomy for PC between 2000 and 2018 were enrolled.

RESULTS

Of the 556 patients who underwent resection, 95 (17%) were elderly (age, ≥75 years). Postoperative complications did not significantly differ between the 2 age groups, and postoperative prognoses were also similar (recurrence-free survival [RFS], P = 0.68; overall survival [OS], P = 0.28). In this cohort, 103 patients (19%) underwent preoperative chemo(radio)therapy, and 417 (77%) underwent postoperative chemotherapy. Perioperative therapy was found to be significantly beneficial for younger patients (preoperative therapy: RFS, P = 0.006; OS, P < 0.001; postoperative therapy: RFS, P < 0.001; OS, P < 0.001). Conversely, no significant survival benefit of perioperative therapy was found for the elderly (preoperative therapy: RFS, P = 0.28; OS, P = 0.44; postoperative therapy: RFS, P = 0.77; OS, P = 0.08).

CONCLUSIONS

This study demonstrated that, although perioperative therapy is feasible for selected elderly patients with PC, this approach might not be as beneficial as it is for younger PC patients.

Prognostic impact of intraoperative peritoneal cytology after neoadjuvant therapy for potentially resectable pancreatic cancer

BACKGROUND

Neoadjuvant therapy (NAT) is considered a potential approach to improve survival for patients with pancreatic adenocarcinoma (PA). The objective of this study was to identify the clinical implications of washing peritoneal cytology (CY) status after NAT.

METHODS

Between 2005 and 2016, 151 consecutive patients with resectable (R)/borderline resectable (BR) PA underwent NAT with intention of subsequent resection at our institution. Of them, 13 and 123 patients underwent pancreatectomies with positive (CY+) and negative (CY-) cytology, respectively, while the remaining 15 patients did not undergo resection due to gross metastases at laparotomy. The clinicopathological factors influencing overall survival were clarified by the uni- and multivariate analyses.

RESULTS

The postoperative overall survival (OS) and disease-free survival (DFS) were markedly worse in patients who underwent resection with CY+, compared with those who were CY- (median OS, 14.8 m vs 30.8 m, p = 0.026, and median DFS 6.0 m vs 15.1 m, p = 0.008). According to the resectability by NCCN guidelines, CY+ indicates worse prognosis than CY- in R-PA patients (mOS: 30.1 m vs 71.1 m: p = 0.080). Similarly, in BR-PA patients, CY+ showed the significantly worse prognosis than CY- (mOS: 13.8 m vs 24.5 m: p = 0.048), which prognosis is comparable with patients who did not undergo resection. The multivariate analysis revealed that resectability, CY status and the induction of adjuvant therapy were significant predictors of postoperative OS (p = 0.007: Hazard ratio 2.264, 0.040:2.094 and 0.002:3.246, respectively).

CONCLUSIONS

CY+ is a significant predictor of poorer prognosis in PA patients after NAT. The subsequent pancreatectomies with CY+ after NAT do not contribute to prolonged survival.