The clinical benefits of performing staging laparoscopy for pancreatic cancer treatment

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.

Is there any role of staging laparoscopy in pancreatic adenocarcinoma?

This is a letter to the editor on a study by Jambor et al. on the role of staging laparoscopy in identifying occult and distant metastases in pancreatic adenocarcinoma patients. In this study, inclusion of staging laparoscopy as an adjunct to computed tomography resulted in an absolute risk reduction of 12.5% for non-therapeutic laparotomy. The study found no correlation between the presence of occult and distant metastases, and serum CA 19-9 level, tumour size or location, which was in significant contrast to a number of other studies. This was likely due to the smaller sample size of the study and restriction to a single high-volume referral centre. It is also noted that staging laparoscopy cannot detect vascular invasion, lymph node involvement and deep hepatic metastases. The sensitivity of peritoneal lavage cytology in detecting occult metastases is low as well. Inclusion of biomarkers like peritoneal lavage tumour DNA may improve sensitivity. Hence, even as this study adds to the evidence supporting staging laparoscopy, further studies on improving the sensitivity of staging laparoscopy are warranted.

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.