Neoadjuvant therapy for pancreatic cancer: an ongoing debate

Comparison of Clinical Outcomes of Borderline Resectable Pancreatic Cancer According to the Neoadjuvant Chemo-Regimens: Gemcitabine versus FOLFIRINOX

Background/Aims

Although many studies have reported the promising effect of neoadjuvant treatment for borderline resectable pancreatic cancer (BRPC) to increase resectability, only a few studies have recommended the use of first-line chemotherapeutic agents as neoadjuvant treatment for BRPC. The current study compared clinical outcomes between gemcitabine and FOLFIRINOX (5-fluorouracil, leucovorin, oxaliplatin, and irinotecan) in patients with BRPC.

Methods

In this single-center retrospective study, 100 BRPC patients treated with neoadjuvant chemotherapy and resection from 2008 to 2018 were reviewed. Clinical outcomes included overall survival, resectability, and recurrence patterns after gemcitabine or FOLFIRINOX treatment.

Results

For neoadjuvant chemotherapy, gemcitabine was administered to 34 patients and FOLFIRINOX to 66. Neoadjuvant radiotherapy was administered to 27 patients (79.4%) treated with gemcitabine and 19 (28.8%) treated with FOLFIRINOX (p<0.001). The 2- and 5-year survival rates (YSRs) were significantly higher after FOLFIRINOX (2YSR, 72.2%; 5YSR, 46.0%) than after gemcitabine (2YSR, 58.4%; 5YSR, 19.1%; p=0.041). The margin negative rate was comparable (gemcitabine, 94.1%; FOLFIRINOX, 92.4%; p=0.753), and the tumor size change in percentage showed only a marginal difference (gemcitabine, 20.5%; FOLFIRINOX, 29.0%; p=0.069). Notably, the metastatic recurrence rate was significantly lower in the FOLFIRINOX group (n=20, 52.6%) than in the gemcitabine group (n=22, 78.6%; p=0.001). The rate of adverse events after chemotherapy was significantly higher with FOLFIRINOX than with gemcitabine (43.9%, 20.6%, respectively; p=0.037).

Conclusions

FOLFIRINOX provided more clinical and oncological benefit than gemcitabine, with significantly higher overall survival and lower cumulative recurrence rates in BRPC. However, since FOLFIRINOX causes more adverse effects, the regimen should be individualized based on patient's general condition and clinical status.

Four-Tier Pathologic Tumor Regression Grading System Predicts the Clinical Outcome in Patients Who Undergo Surgical Resection for Locally Advanced Pancreatic Cancer after Neoadjuvant Chemotherapy

Background/Aims

Neoadjuvant chemotherapy is increasingly utilized in patients with borderline or locally advanced pancreatic cancer (LAPC). However, the pathologic evaluation of tumor regression is not routinely performed or well established. We aimed to evaluate the prognostic value of three tumor regression grading systems frequently used in LAPC and to determine the correlation between pathologic and clinical response.

Methods

We included a total of 38 patients with LAPC who were treated with neoadjuvant chemotherapy and subsequent resection. Pathologic tumor regression was graded based on the College of American Pathologists (CAP), Evans, and MD Anderson grading systems.

Results

One out of 38 patients (2.6%) achieved a pathologic complete response. Unlike other grading systems (Evans, p=0.063; MD Anderson, p=0.110), the CAP grading system was a significant prognostic factor for overall survival (p=0.043). Pathologic N stage (p=0.023), margin status (p=0.044), and radiologic response (p=0.016) correlated with overall survival. In the multivariate analysis, CAP 3 was an independent predictor of shorter overall survival (p=0.026). The CAP grading system correlated with the radiologic response (p=0.007) but not the carbohydrate antigen 19-9 level (p=0.333).

Conclusions

The four-tier CAP pathologic tumor regression grading system predicted the clinical outcome in LAPC patients who underwent resection after neoadjuvant chemotherapy. Therefore, a more comprehensive pathologic evaluation is warranted in these patients.

Outcomes of Neoadjuvant Chemoradiation With and Without Systemic Chemotherapy in Resectable and Borderline Resectable Pancreatic Adenocarcinoma

Introduction: Neoadjuvant therapy is increasingly being used for localized pancreatic adenocarcinoma. While there is evidence supporting neoadjuvant systemic chemotherapy as well as chemoradiation, more evidence is needed to determine whether systemic chemotherapy with chemoradiation offers benefits over chemoradiation alone. This study compares the outcomes of neoadjuvant chemoradiation therapy with and without systemic chemotherapy in resectable and borderline resectable pancreatic cancers.

Methods: This retrospective study evaluated patients with resectable and borderline resectable pancreatic adenocarcinoma who completed neoadjuvant chemoradiation therapy with and without systemic chemotherapy prior to surgical resection. 149 patients met inclusion criteria, with 75 having resectable cancer and 74 having borderline resectable cancer. Outcomes included recurrence free and overall survival rates at 6, 12, and 36 months.

Results: In resectable pancreatic carcinoma, 72% of patients treated with chemoradiation alone achieved 1 year recurrence free survival compared to 78% of patients treated with systemic chemotherapy and chemoradiation (p = 0.55). 28% of patients treated with chemoradiation alone had 3 years recurrence free survival compared to 31% of patients who received systemic and chemoradiation therapy (p = 0.75). In both treatment groups, 92% of patients lived past 1 year (p = 0.92), and 44% of patients survived at least 3 years (p = 0.95). In borderline resectable pancreatic carcinoma, 50% of patients treated with chemoradiation alone achieved 1 year recurrence free survival compared to 70% of patients treated with systemic chemotherapy and chemoradiation (p = 0.079). The 3 years recurrence free survival was 26 and 29% for the chemoradiation alone group and the systemic chemotherapy plus chemoradiation group, respectively (p = 0.85). There was no significant difference in 1 year overall survival: 85% of patients treated with chemoradiation alone survived compared to 92% of patients treated with systemic chemotherapy and chemoradiation (p = 0.32). Both groups had 41% 3 years overall survival (p = 0.96).

Discussion: In resectable and borderline resectable pancreatic adenocarcinoma, there was no significant difference in overall or recurrence free survival between patients treated with chemoradiation with and without systemic chemotherapy. Our findings suggest that systemic neoadjuvant chemotherapy with chemoradiation and chemoradiation alone are efficacious treatments for localized pancreatic carcinoma. This brings into question whether more effective systemic chemotherapy is necessary to increase survival benefit.

Completion of adjuvant therapy in patients with resected pancreatic cancer

BACKGROUND

Adjuvant chemotherapy is the standard of care for resected pancreatic ductal adenocarcinoma (PDAC). It is estimated that only 40-80% eligible patients initiate intended adjuvant chemotherapy. Completion rates are largely unknown.

METHODS

A retrospective analysis of outcomes of patients with resected PDAC over an 8-year period at H. Lee Moffitt Cancer Center (MCC) was performed.

RESULTS

From a total of 309 patients, 299 were included for further analysis. 242 (81%) initiated adjuvant therapy (AT) and 195 (65%) completed the intended course. The median time-to-initiation of AT was 53 days (7.6 weeks). The most common reasons for early discontinuation of AT (n = 47) were toxicity (n = 29), disease recurrence (n = 9), patient decision (n = 4), unrelated comorbidities (n = 3), and death (n = 1). Completion of AT was an independent predictor of overall survival (OS) and recurrence-free survival (RFS) on multivariable analysis (OS: HR 0.41, CI 0.27-0.61, p < 0.001; RFS: HR 0.52, CI 0.36-0.76, p < 0.001). Factors associated with early termination of AT were vascular resection (OR 0.29, CI 0.13-0.67, p = 0.004) and administration of AT with local oncologist as opposed to MCC (OR 0.41, CI 0.21-0.82, p = 0.010).

CONCLUSION

Completion of AT is associated with improved survival in patients with resected PDAC. Factors associated with an inability to complete AT include vascular resection and administration of AT with local care team in the patient's community.

Recent advances in radiation therapy of pancreatic cancer

Pancreatic cancer has a dismal prognosis with an overall survival outcome of just 5% at five years. However, paralleling our improved understanding of the biology of pancreatic cancer, treatment paradigms have also continued to evolve with newer advances in surgical techniques, chemotherapeutic agents, radiation therapy (RT) techniques, and immunotherapy paradigms. RT dose, modality, fraction size, and sequencing are being evaluated actively, and the interplay between RT and immune effects has opened up newer avenues of research. In this review, we will emphasize recent advances in RT for pancreatic cancer, focusing on preoperative chemoradiation, RT dose escalation, sparing of the spleen to reduce lymphopenia, and combination of RT with immunotherapy.

High compliance with guideline recommendations but low completion rates of adjuvant chemotherapy in resected pancreatic cancer: A cohort study

Background

Adjuvant chemotherapy (adCx) is an integral part of multimodal treatment in resected pancreatic ductal adenocarcinoma (PDAC) and is recommended by the German S3 guideline since 2007 in all patients. We aimed to investigate the impact of this guideline at our institution.

Methods

In 151 of 403 pancreatic resections performed histopathology revealed PDAC. Follow-up data were available from 143 patients (95%) representing our study group. The rate of recommended, initiated and fully completed adCx was analyzed for period 1 (09/2003–07/2007) and period 2 (08/2007–08/2014).

Results

Our study group comprised 49 patients in period 1 and 94 patients in period 2. AdCx was recommended, initiated and completed in 42/49 (86%), 34/49 (69%) and 22/49 (45%) patients in period 1 and in 93/94 (99%), 78/94 (83%) and 49/94 (52%) patients in period 2, respectively. Only the increase in recommendations for adCx was statistically significant (p = 0.0024). Overall, only 50% (71/143) of patients fully completed the Cx protocol. Completed adCx resulted in a significantly longer (p = 0.0225) overall survival compared to patients with incomplete or without adCx. Multiple logistic regression revealed adCx (p = 0.0046) as independent factor of survival. The hazard ratio for fully completed adCx was 0.406 and for incomplete adCx 0.567.

Conclusion

Our results indicate a high acceptance of the S3-guidline recommendation for adCx in resected PDAC in a routine setting, which, however, is completed in only 50% of all patients. Fully completed adCx had the most powerful effect on improving overall survival.

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After S3 guideline implementation only the increase in recommendations for adCx was statistically significant.

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Overall, only 50% (71/143) of patients fully completed their Cx protocol.

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Completed adCx resulted in a significantly longer overall survival compared to patients with incomplete or without adCx.

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Multiple logistic regression revealed adCx as an independent factor of survival.

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Our results indicate a high acceptance of the S3-guidline recommendation for adCx in resected PDAC in the routine setting.

Improving outcomes in patients with resectable pancreatic cancer

State of the art

Never let it go: Stopping key mechanisms underlying metastasis to fight pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is an extremely aggressive neoplasm, predicted to become the second leading cause of cancer-related deaths before 2030. This dismal trend is mainly due to lack of effective treatments against its metastatic behavior. Therefore, a better understanding of the key mechanisms underlying metastasis should provide new opportunities for therapeutic purposes. Genomic analyses revealed that aberrations that fuel PDAC tumorigenesis and progression, such as SMAD4 loss, are also implicated in metastasis. Recently, microRNAs have been shown to play a regulatory role in the metastatic behavior of many tumors, including PDAC. In particular, miR-10 and miR-21 have appeared as master regulators of the metastatic program, while members of the miR-200 family are involved in the epithelial-to-mesenchymal switch, favoring cell migration and invasiveness. Several studies have also found a close relationship between cancer stem cells (CSCs) and biological features of metastasis, and the CSC markers ALDH1, ABCG2 and c-Met are expressed at high levels in metastatic PDAC cells. Emerging evidence reveals that exosomes are involved in the modulation of the tumor microenvironment and can initiate PDAC pre-metastatic niche formation in the liver and lungs. In this review, we provide an overview of the role of all these pivotal factors in the metastatic behavior of PDAC, and discuss their potential exploitation in the clinic to improve current therapeutics and identify new drug targets.