Neoadjuvant Phase II Trial of Chemoradiotherapy in Patients With Resectable and Borderline Resectable Pancreatic Cancer

Efficacy and safety of neoadjuvant S-1-based chemoradiotherapy in resectable and borderline-resectable pancreatic cancer: a long-term follow-up study

BACKGROUND/OBJECTIVES

This study aimed to evaluate the safety, efficacy, and long-term outcomes of S-1-based neoadjuvant chemoradiotherapy (NACRT) in patients with resectable or borderline-resectable pancreatic ductal adenocarcinoma (PDAC).

METHODS

This retrospective study included patients with PDAC who underwent S-1-based NACRT at our institute between 2010 and 2017.

RESULTS

Forty patients were included in the study, including 15 (37.5%) with resectable PDAC and 25 (62.5%) with borderline-resectable PDAC. The NACRT completion and resection rates were 85.0% (n = 34) and 67.5% (n = 27), respectively. Several grade 3 adverse events were observed, including leukopenia (25.0%), anorexia (17.5%), neutropenia (10.0%), thrombocytopenia (7.5%), febrile neutropenia (2.5%), elevated aspartate aminotransferase/alanine aminotransferase (2.5%) levels, and hyponatremia (2.5%). The R0 resection rate was 70.4% (n = 19/27) in patients who underwent pancreatectomy. Grades 1, 2, and 3 according to the College of American Pathologists grading system were observed in 1 (3.7%), 12 (44.4%), and 14 (51.9%) patients, respectively. Over a median follow-up period of 32.9 months (interquartile range, 9.1-68.0), the 1-, 3-, and 5-year OS rates were 81.4%, 45.5%, and 30.3%, respectively, in the intention-to-treat analysis. In the curative-intent surgery cohort (n = 27), the 1-, 3-, and 5-year OS rates were 88.9%, 48.2%, and 37.0%, respectively.

CONCLUSIONS

S-1-based NACRT is safe and yields acceptable long-term outcomes for patients with resectable or borderline-resectable PDAC.

MUC16 Retention after Neoadjuvant Chemotherapy in Pancreatic Ductal Adenocarcinoma

Background/Objectives: Pancreatic ductal adenocarcinoma (PDAC) has a poor prognosis. Currently, surgical resection is the only potentially curative treatment. Unfortunately, less than 20% of PDAC patients are eligible for surgical resection at diagnosis. In the past few decades, neoadjuvant chemotherapy treatment (NCT) has been investigated as a way to downstage PDAC tumors for surgical resection. Fluorescence-guided surgery (FGS) is a technique that can aid in increasing complete resection rates by enhancing the tumor through passive or active targeting of a contrast agent. In active targeting, a probe (e.g., antibody) binds a protein differentially upregulated in the tumor compared to normal tissue. Mucin 16 (MUC16), a transmembrane glycoprotein, has recently been explored as an FGS target in preclinical tumor models. However, the impact of chemotherapy on MUC16 expression is unknown. Methods: To investigate this issue, immunohistochemistry was performed on PDAC patient samples. Results: We found that MUC16 expression was retained after NCT in patient samples (mean expression = 5.7) with minimal change in expression between the matched diagnostic (mean expression = 3.66) and PDAC NCT patient samples (mean expression = 4.5). Conclusions: This study suggests that MUC16 is a promising target for FGS and other targeted therapies in PDAC patients treated with NCT.

Comprehensive multimodal management of borderline resectable pancreatic cancer: Current status and progress

Borderline resectable pancreatic cancer (BRPC) is a complex clinical entity with specific biological features. Criteria for resectability need to be assessed in combination with tumor anatomy and oncology. Neoadjuvant therapy (NAT) for BRPC patients is associated with additional survival benefits. Research is currently focused on exploring the optimal NAT regimen and more reliable ways of assessing response to NAT. More attention to management standards during NAT, including biliary drainage and nutritional support, is needed. Surgery remains the cornerstone of BRPC treatment and multidisciplinary teams can help to evaluate whether patients are suitable for surgery and provide individualized management during the perioperative period, including NAT responsiveness and the selection of surgical timing.

Defining the Optimal Duration of Neoadjuvant Therapy for Pancreatic Ductal Adenocarcinoma: Time for a Personalized Approach?

ABSTRACT

Despite recent advances, pancreatic ductal adenocarcinoma (PDAC) continues to be associated with dismal outcomes, with a cure evading most patients. While historic treatment for PDAC has been surgical resection followed by 6 months of adjuvant therapy, there has been a recent shift toward neoadjuvant treatment (NAT). Several considerations support this approach, including the characteristic early systemic spread of PDAC, and the morbidity often surrounding pancreatic resection, which can delay recovery and preclude patients from starting adjuvant treatment. The addition of NAT has been suggested to improve margin-negative resection rates, decrease lymph node positivity, and potentially translate to improved survival. Conversely, complications and disease progression can occur during preoperative treatment, potentially eliminating the chance of curative resection. As NAT utilization has increased, treatment durations have been found to vary widely between institutions with an optimal duration remaining undefined. In this review, we assess the existing literature on NAT for PDAC, reviewing treatment durations reported across retrospective case series and prospective clinical trials to establish currently used approaches and seek the optimal duration. We also analyze markers of treatment response and review the potential for personalized approaches that may help clarify this important treatment question and move NAT toward a more standardized approach.

The impact of race/ethnicity on pancreaticoduodenectomy outcomes for pancreatic cancer

PURPOSE

To investigate the impact of race/ethnicity on surgical outcomes following pancreaticoduodenectomy for pancreatic cancer.

METHODS

A retrospective review of patients undergoing pancreaticoduodenectomy for adenocarcinoma in the National Surgical Quality Improvement Program (NSQIP) database from 2014 to 2019. Patient and tumor characteristics and 30-day postoperative outcomes were compared. Multivariable logistic and linear regression models were conducted to investigate the relationship between race/ethnicity and surgical outcomes.

RESULTS

Six thousand five hundred and sixty-two patients were included (84.5% White, 7.9% Black, 3% Hispanic, 4.6% Asian). Larger proportions of Blacks had preoperative American Society of Anesthesiologists class 3 or 4. There were no significant differences in tumor characteristics or operative techniques. A smaller proportion of Asians and Hispanics received neoadjuvant chemotherapy and/or radiation than Blacks and Whites. Relative to White, the Black race was independently associated with postoperative sepsis and reoperation. Both Black and Hispanic race/ethnicity were associated with prolonged intubation and delayed gastric emptying, and minorities races/ethnicities were associated with longer length of hospital stay. Relative to White, Hispanic, and Asian race/ethnicity were independently associated with a lower likelihood of neoadjuvant therapy (NAT) receipt.

CONCLUSION

In ACS-NSQIP participating hospitals, non-White race/ethnicity was independently associated with adverse outcomes after pancreatic cancer resection. A possible disparity in NAT receipt may exist in Asian and Hispanic patients undergoing surgical resection.

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.

Neoadjuvant Treatment in Resectable Pancreatic Cancer. Is It Time for Pushing on It?

Pancreatic resection still represents the only curative option for patients affected by pancreatic ductal adenocarcinoma (PDAC). However, the association with modern chemotherapy regimens is a key factor in improving the inauspicious oncological outcome. The benefit of neoadjuvant treatment (NAT) for borderline resectable/locally advanced PDAC has been demonstrated; this evidence raises the question of whether even resectable PDAC should undergo NAT rather than upfront surgery. NAT may avoid futile surgery because of undetected distant metastases or aggressive tumor biology, providing more effective systemic control of the disease, which is hampered when adjuvant chemotherapy is delayed or precluded. However, recent data show controversial results regarding the efficacy and safety of NAT in resectable PDAC compared to upfront surgery. Although several prospective studies and meta-analyses indicate better oncologic outcomes after NAT, there are some biases, such as the methodological approaches used to capture the events of interest, which could make these results hardly reproducible. For instance, per-protocol studies, considering only the postoperative outcomes, tend to overestimate the performance of NAT by excluding patients who will never be suitable for surgery due to the development of chemotoxicity or tumor progression. To draw reliable conclusions, the studies should capture the events of interest of both strategies (NAT/upfront surgery) from the time of allocation to a specific treatment in an intention-to-treat fashion. This critical review highlights the current literature data concerning the use of NAT in resectable PDAC, summarizing the results of high-quality studies and focusing on the methodological issues of the most recent pieces of evidence.

Total neoadjuvant therapy for initially inoperable pancreatic cancer: A systematic review of phase 2-3 studies

INTRODUCTION

Patients with initially inoperable non-metastatic pancreatic cancer (PC) have a poor prognosis, often similar to those with metastatic disease. Neoadjuvant chemotherapy (CT) plus concomitant or sequential radiotherapy (RT) may cause tumor shrinkage and allow for radical surgery. We pooled data of studies in which patients with locally advanced (unresectable) or borderline resectable PC were treated with a course of induction (or consolidation) CT followed or preceded by neoadjuvant CTRT regimen.

MATERIALS AND METHODS

We searched articles, including phase 2 or 3 studies, published in English from 2010 up to December 2020 in PubMed, SCOPUS, the Cochrane Library, and EMBASE. The primary outcomes were the pooled radical and R0 resection rates, median PFS and OS of included patients (those included in the intent to treat analysis).

RESULTS

A total of 28 studies were finally considered eligible for inclusion in quantitative analysis for a total of 2446 patients with locally advanced/borderline resectable PC. Overall the pooled rate of resection was 29.7% (95%CI 26.7-32.8%). In patients who completed the CT + CTRT program, the overall resection rate was 31.8% (95% 28.4-35.4%). After exclusion of studies that included resectable PCs, the overall resection rate was 19.9% (95%CI 17.3-22.7%). In studies were all patients had unresectable PC (n = 20 studies), the resection rate was 12.1% (95%CI 10-14.5%). In two studies that enrolled all borderline resectable PCs the resection rate was 59.2% (95%CI 48.9-68.8%). The pooled R0 resection rate was 68.7% (95%CI 64.7-72.3%). The median pooled OS was 15.7 months (95%CI 14-17.2 months) and the median pooled PFS was 10.7 (95%CI 9.3-12.1 months).

CONCLUSIONS

Surgery is a treatment option in about one third of patients with initially inoperable PC, following total neoadjuvant therapy. In unresectable cases the resection rate was 12%. Median OS and PFS rates were comparable with historical data of advanced PCs. Optimal integration and sequence of chemo- and radiotherapy in unresectable PC must still be defined.

Analysis of the Curative Effect of Neoadjuvant Therapy on Pancreatic Cancer

The prevalence of pancreatic cancer is sharply increasing recently, which significantly increases the economic burden of the population. At present, the primary treatment of resectable pancreatic cancer is surgical resection, followed by chemotherapy with or without radiation. However, the recurrence rates remain high even after R0 resection. This treatment strategy does not distinguish undetected metastatic disease, and it is prone to postoperative complications. Neoadjuvant therapies, including neoadjuvant chemotherapy and radiotherapy, is being increasingly utilized in borderline resectable as well as resectable pancreatic cancer. This review summarized and discussed clinical trials of neoadjuvant therapy for pancreatic cancer, comparing resection rates, outcome measures, and adverse reactions between neoadjuvant chemotherapy and neoadjuvant chemoradiotherapy.

Prognostic value of platelet-to-lymphocyte ratio in neoadjuvant chemotherapy for solid tumors: A PRISMA-compliant meta-analysis

INTRODUCTION

Previous research indicates that the platelet-to-lymphocyte ratio (PLR) may be an indicator of poor prognosis in many tumor types. However, the PLR is rarely described in patients undergoing neoadjuvant chemotherapy (NAC) for solid tumors. Thus, we performed a meta-analysis to investigate the prognostic value of this ratio for patients with solid tumors treated by NAC.

METHODS

A comprehensive search of the literature was conducted using the PubMed, EMBASE, Cochrane Library, and Web of Science databases, followed by a manual search of references from the retrieved articles. Pooled hazard ratios (HRs) with 95% confidence interval (CIs) were used to evaluate the association between PLR and 3 outcomes, namely, overall survival, disease-free survival, and pathological complete response rate after NAC.

RESULTS

Eighteen studies published no earlier than 2014 were included in our study. A lower PLR was associated with better overall survival (HR = 1.46, 95% CI, 1.11-1.92) and favorable disease-free survival (HR = 1.81, 95% CI, 1.27-2.59). A PLR that was higher than a certain cutoff was associated with a lower pathological complete response rate in patients with cancer who received NAC (Odds ratio = 1.93, 95% CI, 1.40-2.87).

CONCLUSION

Elevated PLR is associated with poor prognosis in various solid tumors. PLR may be a useful biomarker in delineating those patients with poorer prognoses who may benefit from neoadjuvant therapies.