Clinical Significance of Neoadjuvant Chemotherapy With Gemcitabine Plus S-1 for Resectable Pancreatic Ductal Adenocarcinoma

The survival effect of neoadjuvant therapy and neoadjuvant plus adjuvant therapy on pancreatic ductal adenocarcinoma patients with different TNM stages: a propensity score matching analysis based on the SEER database

BACKGROUND

Adjuvant therapy (AT) and neoadjuvant therapy (NAT) are standard treatments for pancreatic ductal adenocarcinoma (PDAC) depending on the status of the disease. However, whether AT improves survival after NAT and radical resection in all TNM stages remains unclear.

RESEARCH DESIGN AND METHODS

We utilized the Surveillance, Epidemiology, and End Results (SEER) database (2010-2019) for PDAC patients who underwent radical surgery and applied Pearson's chi-square test, multivariate and univariate Cox regression, Kaplan-Meier plot, Log-rank tests, and propensity score matching (PSM) for analysis.

RESULTS

Given PSM after enrolling 13,868 PDAC patients, significant differences in survival were identified between AT and neoadjuvant therapy plus adjuvant therapy (NATAT) (p = 0.023) as well as between NAT and NATAT (p < 0.001). According to the AJCC 8th TNM stage, a survival advantage associated with NATAT was exclusively observed in stage III and IV disease, except for T4N0M0. Some stage IV patients receiving NATAT exhibited comparable survival to their counterparts without metastasis.

CONCLUSIONS

In this retrospective cohort study, we demonstrated that patients harboring tumors in late TNM stages, including N2 resectable PDAC, might have better survival from NATAT, and that certain patients with M1 disease might still benefit from comprehensive systemic therapy and radical resection.

The benefits of neoadjuvant therapy for patients with resectable pancreatic cancer: an updated systematic review and meta-analysis

Neoadjuvant therapy (NAT) was effective in improving overall survival (OS) of borderline resectable pancreatic cancer. However, its application in resectable pancreatic cancer remains controversial. This study aimed to determine whether NAT has a greater advantage over conventional upfront surgery (US) in terms of resection rate, R0 resection rate, positive lymph node rate, and OS. We identified articles before October 7, 2022, by searching four electronic databases. The studies included in the meta-analysis all met the inclusion and exclusion criteria. The Newcastle-Ottawa scale was used to evaluate the quality of the articles. OS, DFS, resection rate, R0 resection rate and positive lymph nodes rate were extracted. Odds ratio (OR), hazard ratio (HR) and 95% confidence intervals (CI) were calculated, and sensitivity analysis and publication bias were used to assess the sources of heterogeneity. In total, 24 studies, involving 1384 (35.66%) patients assigned to NAT and 2497 (64.43%) patients assigned to US, were included in the analysis. NAT could effectively prolong OS (HR 0.73, 95% CI 0.65-0.82, P < 0.001) and DFS (HR 0.72, 95% CI 0.62-0.84, P < 0.001). Subgroup analysis results of 6 randomized controlled trials (RCTs) also showed that RPC patients could benefit from NAT in the long term (HR 0.72, 95% CI 0.58-0.90, P = 0.003). NAT decreased resection rate (OR 0.43, 95% CI 0.33-0.55, P < 0.001), but was associated with increased R0 resection rate (OR 2.05, 95% CI 1.47-2.88, P < 0.001) and decreased positive lymph node rate (OR 0.38, 95% CI 0.27-0.52, P < 0.001). Although the application of NAT increases the risk of patients not being able to undergo surgical resection, it can prolong the OS and delay tumor progression in RPC. Therefore, we still expect larger and higher-quality RCTs to confirm the effectiveness of NAT.

Effect and limitation of neoadjuvant chemotherapy for pancreatic ductal adenocarcinoma: consideration from a new perspective

BACKGROUND

Effect of neoadjuvant chemotherapy (NAC) for pancreatic ductal adenocarcinoma (PDAC) has remained under investigation. We investigated its effect from a unique perspective and discussed its application.

PATIENTS AND METHODS

We retrospecively analyzed consecutive 131 PDAC patients who underwent pancreatoduodenectomy and distal pancreatectomy. Clinicopathologic data at surgery and postoperative prognosis were compared between patients who underwent upfront surgery (UFS) (n = 64) and those who received NAC (n = 67), of which 62 (92.5%) received gemcitabine plus S-1 (GS). The GS regimen resulted in about 15% of partial response and 85% of stable disease in a previous study which analyzed a subset of this study subjects.

RESULTS

Tumor size was marginally smaller, degree of nodal metastasis and rate of distant metastasis were significantly lower, and pathologic stage was significantly lower in the NAC group than in the UFS group. In contrast, significant differences were not observed in histopathologic features such as vessel and perineural invasions and differentiation grade. Notably, disease-free and overall survivals were similar between the two groups adjusted for the pathologic stage, suggesting that effects of NAC, including macroscopically undetectable ones such as control of micro-metastasis and devitalizing tumor cells, may not be remarkable in the majority of PDAC, at least with respect to the GS regimen.

CONCLUSIONS

NAC may be useful in downstaging and improving prognosis in a small subset of tumors. However, postoperative prognosis may be determined at the pathologic stage of resected specimen with or without NAC. Therefore, NAC may be applicable to borderline resectable and locally advanced PDAC for enabling surgical resection, but UFS would be desirable for primary resectable PDAC.

Comparison of plastic stent versus metal stent in preoperative biliary drainage for pancreatic head cancer with neoadjuvant chemoradiotherapy

BACKGROUND

While neoadjuvant chemotherapy and chemoradiotherapy (NACRT) for pancreatic head cancer are effective, preoperative endoscopic biliary drainage (EBD) is necessary for managing obstructive jaundice and cholangitis during the preoperative waiting period. Nevertheless, ideal choice of stent type is unclear. We compared plastic stents (PS) and metal stents (MS) in these situations.

METHODS

We retrospectively studied 43 patients who successfully underwent preoperative EBD prior to NACRT for pancreatic head cancer at a single institution. We divided patients into PS (n = 22) and MS (n = 21) groups. The primary outcome was the rate of re-interventional drainage rate before surgery. Secondary outcomes were rates of EBD-associated and postoperative complications and total costs in the pre- and perioperative periods.

RESULTS

The re-intervention rate was significantly greater in the PS group than in the MS group (95% vs 4.8%, respectively, P < 0.05). EBD-associated and postoperative complications were significantly less common in the MS group (P < 0.05). The average total preoperative medical costs were significantly lower in the MS group (PS vs MS: 528,597 vs 395,891 JPY, P = 0.004).

CONCLUSIONS

MS can be the first choice for EBD in patients undergoing NACRT for pancreatic head cancer. MS may be less costly overall.