Radiographic patterns of first disease recurrence after neoadjuvant therapy and surgery for patients with resectable and borderline resectable pancreatic cancer

Prognostication for recurrence patterns after curative resection for pancreatic ductal adenocarcinoma

Backgrounds/Aims

This study aimed to investigate patterns and factors affecting recurrence after curative resection for pancreatic ductal adenocarcinoma (PDAC).

Methods

Consecutive patients who underwent curative resection for PDAC (2011-21) and consented to data and tissue collection (Barts Pancreas Tissue Bank) were followed up until May 2023. Clinico-pathological variables were analysed using Cox proportional hazards model.

Results

Of 91 people (42 males [46%]; median age, 71 years [range, 43-86 years]) with a median follow-up of 51 months (95% confidence intervals [CIs], 40-61 months), the recurrence rate was 72.5% (n = 66; 12 loco-regional alone, 11 liver alone, 5 lung alone, 3 peritoneal alone, 29 simultaneous loco-regional and distant metastases, and 6 multi-focal distant metastases at first recurrence diagnosis). The median time to recurrence was 8.5 months (95% CI, 6.6-10.5 months). Median survival after recurrence was 5.8 months (95% CI, 4.2-7.3 months). Stratification by recurrence location revealed significant differences in time to recurrence between loco-regional only recurrence (median, 13.6 months; 95% CI, 11.7-15.5 months) and simultaneous loco-regional with distant recurrence (median, 7.5 months; 95% CI, 4.6-10.4 months; p = 0.02, pairwise log-rank test). Significant predictors for recurrence were systemic inflammation index (SII) ≥ 500 (hazard ratio [HR], 4.5; 95% CI, 1.4-14.3), lymph node ratio ≥ 0.33 (HR, 2.8; 95% CI, 1.4-5.8), and adjuvant chemotherapy (HR, 0.4; 95% CI, 0.2-0.7).

Conclusions

Timing to loco-regional only recurrence was significantly longer than simultaneous loco-regional with distant recurrence. Significant predictors for recurrence were SII, lymph node ration, and adjuvant chemotherapy.

Long-term outcomes of neoadjuvant gemcitabine, nab-paclitaxel, and S1 (GAS) in borderline resectable pancreatic cancer with arterial contact: Results from a phase II trial

BACKGROUND/PURPOSE

This study reports the long-term results of a phase II trial evaluating the clinical efficacy of neoadjuvant gemcitabine, nab-paclitaxel, and S1 (GAS) in borderline resectable pancreatic cancer with arterial contact (BRPC-A).

METHODS

A multicenter, single-arm, phase II trial was conducted. Patients received six cycles of GAS and patients without progressive disease were intended for R0 resection.

RESULTS

Of the 47 patients, 45 (96%) underwent pancreatectomy. At the time of this analysis, all patients were updated with no loss to follow-up. A total of 30 patients died, while the remaining 17 patients were followed for a median of 68.1 months. The updated median overall survival (OS) was 41.0 months, with 2- and 5-year OS rates of 68.0% and 44.6%, respectively. Multivariate analysis in the preoperative model showed that a tumor diameter reduction rate ≥10% and a CA19-9 reduction rate ≥95% after neoadjuvant chemotherapy remained independently associated with favorable survival. In the postoperative multivariate model, no lymph node metastasis, no major surgical complications, and completion of adjuvant chemotherapy were independently associated with improved OS.

CONCLUSIONS

This long-term evaluation of the neoadjuvant GAS trial demonstrated the high efficacy of the regimen, suggesting that it is a promising treatment option for patients with BRPC-A.

No survival benefit with suboptimal CA19-9 response: defining effective neoadjuvant chemotherapy in resectable or borderline resectable pancreatic cancer

BACKGROUND/PURPOSE

Neoadjuvant chemotherapy (NAC) is gaining popularity over a surgery-first (SF) approach in treating resectable and borderline resectable pancreatic ductal adenocarcinoma (PDAC). However, what constitutes effective neoadjuvant chemotherapy is unknown.

METHODS

We retrospectively analyzed resectable and borderline resectable PDAC patients who underwent pancreaticoduodenectomy (2010-2019) at a single institution. Optimal CA19-9 response was defined as normalization AND >50% reduction. We utilized Kaplan-Meier and multivariable-adjusted Cox models and competing risk subdistribution methods for statistical analysis.

RESULTS

586 patients were included in this study. The multivariable-adjusted analysis demonstrated OS benefit in the NAC group only when OS was calculated from diagnosis (HR = 0.72, p = 0.02), but not from surgery (HR = 0.81, p = 0.1). However, in 59 patients who achieved optimal CA19-9 response, OS is significantly longer than the 134 patients with suboptimal CA19-9 response (39.3 m vs. 21.5 m, p = 0.005) or the 117 SF patients (39.3 m vs. 19.5 m, p < 0.001). Notably, a suboptimal CA19-9 response conferred no OS advantage compared to SF patients. The accumulative incidence of liver metastases (but not other metastases) was significantly reduced only in patients with optimal CA19-9 response to NAC (multivariable-adjusted subdistribution HR = 0.26, p = 0.03).

CONCLUSION

CA19-9 response to NAC may serve as the marker for effective NAC. These findings warrant validation in a multi-institutional study.

Impact of margin accentuation with intraoperative irreversible electroporation on local recurrence in resected pancreatic cancer

BACKGROUND

The purpose of this study was to evaluate the rates of local recurrence and margin positivity in patients with borderline resectable pancreatic cancer after pancreatectomy with or without irreversible electroporation with margin accentuation.

METHODS

Prospective data for preoperative stages IIB (borderline resectable) and III were evaluated, with 75 patients undergoing pancreatectomy with irreversible electroporation with margin accentuation compared to 71 patients who underwent pancreatectomy alone from March 2010 to November 2020.

RESULTS

Both irreversible electroporation with margin accentuation and pancreatectomy-alone groups were similar for body mass index, Charleston comorbidity index, and sex. The irreversible electroporation with margin accentuation group had significantly greater preoperative stage III (irreversible electroporation 83% vs pancreatectomy alone 51%; P = .0001), with similar tumor location (head 64% vs 72%) and tumor size (median 2.9 vs 2.8). Neoadjuvant/induction chemotherapy and prior radiation therapy was similar in both groups (irreversible electroporation with margin accentuation 89% vs 72%). Surgical therapy included a greater percentage of pancreaticoduodenectomy in the pancreatectomy-alone group. Despite greater stage and greater percentage of margin positivity (irreversible electroporation with margin accentuation 27% vs 20%; P = not significant), rates of local recurrence were similar. The mean disease-free interval for local recurrence from time of diagnosis was similar (irreversible electroporation with margin accentuation 15.8 vs 16.5 pancreatectomy alone; P = not significant) and time of treatment (irreversible electroporation with margin accentuation 9.4 vs 10.5 months; P = not significant). Overall survival was improved with the irreversible electroporation with margin accentuation group, with a mean of 34.2 months versus 27.9 months in the pancreatectomy-alone group.

CONCLUSION

Irreversible electroporation with margin accentuation is safe and effective in stages IIB and III pancreatic adenocarcinomas that are technically resectable. Despite higher margin positivity rates, the time to local recurrence and the effects of recurrence were the same in the pancreatectomy-alone group.

Can Concurrent Chemoradiotherapy Add Meaningful Benefit in Addition to Induction Chemotherapy in the Management of Borderline Resectable and Locally Advanced Pancreatic Cancer?: A Systematic Review

OBJECTIVES

The role of concomitant chemoradiotherapy or radiotherapy (RT) after induction chemotherapy (IC) in borderline resectable and locally advanced pancreatic ductal adenocarcinoma is debatable. This systematic review aimed to explore this.

METHODS

We searched PubMed, MEDLINE, EMBASE, and Cochrane database. Studies were selected reporting outcomes on resection rate, R0 resection, pathological response, radiological response, progression-free survival, overall survival, local control, morbidity, and mortality.

RESULTS

The search resulted in 6635 articles. After 2 rounds of screening, 34 publications were selected. We found 3 randomized controlled studies and 1 prospective cohort study, and the rest were retrospective studies. There is consistent evidence that addition of concomitant chemoradiotherapy or RT after IC improves pathological response and local control. There are conflicting results in terms of other outcomes.

CONCLUSIONS

Concomitant chemoradiotherapy or RT after IC improves local control and pathological response in borderline resectable and locally advanced pancreatic ductal adenocarcinoma. The role of modern RT in improving other outcome requires further research.

CA19.9 Response and Tumor Size Predict Recurrence Following Post-neoadjuvant Pancreatectomy in Initially Resectable and Borderline Resectable Pancreatic Ductal Adenocarcinoma

BACKGROUND

Data on recurrence after post-neoadjuvant pancreatectomy are scant. This study investigated the incidence and pattern of recurrence in patients with initially resectable and borderline resectable pancreatic ductal adenocarcinoma who received post-neoadjuvant pancreatectomy. Furthermore, preoperative predictors of recurrence-free survival (RFS) and their interactions were determined.

PATIENTS AND METHODS

Patients undergoing post-neoadjuvant pancreatectomy at two academic facilities between 2013 and 2017 were analyzed using standard statistics. The possible interplay between preoperative parameters was scrutinized including interaction terms in multivariable Cox models.

RESULTS

Among 315 included patients, 152 (48.3%) were anatomically resectable. The median RFS was 15.7 months, with 1- and 3-year recurrence rates of 41.9% and 74.2%, respectively. Distant recurrence occurred in 83.3% of patients, with lung-only patterns exhibiting the most favorable prognostic outlook. Normal posttreatment CA19.9, ΔCA19.9 (both in patients with normal and elevated baseline levels), and posttreatment tumor size were associated with RFS. Critical thresholds for ΔCA19.9 and tumor size were set at 50% and 20 mm, respectively. Interaction between ΔCA19.9 and posttreatment CA19.9 suggested a significant risk reduction in patients with elevated values when ΔCA19.9 exceeded 50%. Moreover, posttreatment tumor size interacted with posttreatment CA19.9 and ΔCA19.9, suggesting an increased risk in the instance of elevated posttreatment CA19.9 values and a protective effect associated with CA19.9 response in patients with tumor size >20 mm.

CONCLUSION

Recurrence following post-neoadjuvant pancreatectomy is common. Preoperative tumor size <20 mm, normal posttreatment CA19.9 and ΔCA19.9 > 50% were associated with longer RFS. These variables should not be taken in isolation, as their interaction significantly modulates the recurrence risk.

Impact of the aberrant right hepatic artery on local recurrence of pancreatic ductal adenocarcinoma after pancreaticoduodenectomy

BACKGROUND

The influence and risk associated with an aberrant right hepatic artery, a common anatomical variation, during pancreatoduodenectomy for pancreatic ductal adenocarcinoma has not been fully investigated. The present study analyzed the impact of an aberrant right hepatic artery on local recurrence after pancreatoduodenectomy for pancreatic ductal adenocarcinoma.

METHODS

A total of 169 patients with pancreatic ductal adenocarcinoma who underwent pancreatoduodenectomy at 2 separate Japanese medical institutions were retrospectively analyzed.

RESULTS

Thirty of 169 patients (17.7%) presented with an aberrant right hepatic artery. The incidence of local recurrence was higher in the aberrant right hepatic artery group than in the normal right hepatic artery group (43.3 vs 21.5%, P = .017). The local recurrence-free survival was significantly poorer in the aberrant right hepatic artery group than in the normal right hepatic artery group (P = .011). A multivariate analysis found that the aberrant right hepatic artery was an independent risk factor for local recurrence (hazard ratio: 3.74, P = .017). In the aberrant right hepatic artery group, more frequent local recurrence was observed in patients with tumors situated ≤10 mm from the aberrant right hepatic artery root. However, local recurrence was not observed in 2 out of 3 patients with tumors ≤10 mm from the aberrant right hepatic artery root who underwent pancreatoduodenectomy with combined resection of the aberrant right hepatic artery.

CONCLUSION

The presence of an aberrant right hepatic artery in patients undergoing pancreatoduodenectomy for pancreatic ductal adenocarcinoma may be associated with an increased risk of postoperative local recurrence. Combined resection of the aberrant right hepatic artery may reduce local recurrence, especially for tumors near the root of the aberrant right hepatic artery.

Radiation therapy in borderline resectable pancreatic cancer: A review

BACKGROUND

Borderline resectable pancreatic cancer constitutes a complex clinical entity, presenting the clinician with a locally aggressive disease that has a proclivity for distant spread. The benefits of radiation therapy, such as improved local control and improved survival, have been questioned. In this review we seek to summarize the existing evidence on radiation therapy in borderline resectable pancreatic cancer and highlight future areas of research.

METHODS

A comprehensive review of PubMed for clinical studies reporting outcomes in borderline resectable pancreatic cancer was performed in June 2021, with an emphasis placed on prospective studies.

RESULTS

Radiologic "downstaging" in borderline resectable pancreatic cancer is a rare event, although some evidence shows increased clinical response to neoadjuvant chemotherapy over radiation therapy. Margin status seems to be equivalent between regimens that use neoadjuvant chemotherapy alone and regimens that include neoadjuvant radiation therapy. Local control in borderline resectable pancreatic cancer is likely improved with radiation therapy; however, the benefit of improved local control in a disease marked by systemic failure has been questioned. Although some studies have shown improved survival with radiation therapy, differences in the delivery and tolerance of chemotherapy between the neoadjuvant and adjuvant setting confound these results. When the evidence is evaluated as a whole, there is no clear survival benefit of radiation therapy in borderline resectable pancreatic cancer.

CONCLUSION

Once considered a staple of therapy, the role of radiation therapy in borderline resectable pancreatic cancer is evolving as systemic therapy regimens continues to improve. Increased clinical understanding of disease phenotype and response are needed to accurately tailor therapy for individual patients and to improve outcomes in this complex patient population.

Evolution of Systemic Therapy in Metastatic Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma is characterized by early systemic dissemination, a complex tumor microenvironment, as well as significant intratumoral and intertumoral heterogeneity. Treatment options and survival in pancreatic ductal adenocarcinoma have improved steadily over the last 3 decades. Although cytotoxic chemotherapy is currently the mainstay of treatment for pancreatic ductal adenocarcinoma, evolving therapeutic strategies are aimed at targeting the tumor microenvironment, metabolism, and the tumor-host immune balance.

Ten-year experience in optimizing neoadjuvant therapy for localized pancreatic cancer-Medical college of Wisconsin perspective

Treatment of localized pancreatic cancer has also evolved to prioritize preoperative (neoadjuvant) multimodality therapy over a surgery-first approach. Given the complexities of pancreatic cancer staging and the challenge of delivering multiple treatment modalities (chemotherapy, radiation therapy, and surgery), an experienced and highly integrated multidisciplinary team is necessary to achieve the best outcomes. In this review, we will discuss our institutional experience with neoadjuvant therapy, guiding principles for treatment, and outline the landscape for future investigations.