Efficacy of immune checkpoint inhibitors in microsatellite unstable/mismatch repair-deficient advanced pancreatic adenocarcinoma: an AGEO European Cohort

Kikuchi disease: A case report about Sintilimab-induced Kikuchi histiocytic necrotizing lymphadenitis and literature review

Immune checkpoint inhibitors have become one of the effective means of solid tumor treatment, among which anti-programmed death-1 (PD-1) antibodies are more maturely applied and can effectively inhibit tumor immune escape, thus enhancing the anti-tumor effect, but it can also lead to a series of immune-related adverse events (irAEs) in the process of clinical use. Here, we report a Patient with pancreatic solid pseudopapilloma treated with Sintilimab for the fifteenth cycles who developed chills, fever, and lymph node enlargement. Considering that the patient did not have infection, without history of autoimmune disease, we diagnosed the patient with Sintilimab-induced histiocytic necrotizing lymphadenitis (Kikuchi disease). The symptoms are alleviated after rapid use of glucocorticoids. Histiocytic necrotizing lymphadenitis (Kikuchi lymphadenitis) with anti-programmed death-1 (PD-1) antibody is a rare immune-related adverse events (irAEs).

Second-Line Treatment of Pancreatic Adenocarcinoma: Shedding Light on New Opportunities and Key Talking Points from Clinical Trials

Despite improvements in overall cancer mortality, deaths related to pancreatic cancer continue to rise. Following first-line treatment, second-line options are significantly limited. Classically, first-line treatment consisted of either gemcitabine or 5-fluorouracil based systemic chemotherapy. Upon progression of disease or recurrence, subsequent second-line treatment is still gemcitabine or 5-fluorouracil based chemotherapy, depending on what was used in the first line and the timing of progression or recurrence. A better understanding of the molecular underpinnings of pancreatic adenocarcinoma (PDAC) has led to new treatment strategies including specifically targeting the desmoplastic stroma, cytokine signaling and actionable mutations. Furthermore, efforts are also directed to enhance the immunogenicity profile of PDAC's well-established immunologically "cold" tumor microenvironment. More recently, the outstanding response rates of chimeric antigen receptor T (CAR-T) cells in hematologic malignancies, have led to clinical trials to evaluate the treatment modality in PDAC. In this review, we summarize recently presented clinical trials for metastatic pancreatic adenocarcinoma with novel treatment approaches in the second line and beyond.

[The use of targeted therapies in gastrointestinal oncology]

In recent years, several drugs have been approved that specifically target molecular changes in tumour cells. For patients with gastrointestinal cancer, this has contributed to a significant improvement in prognosis. This article provides an overview of the currently available treatment options and the underlying biomarkers of their mechanisms of action.The evaluation of biomarkers and the use of targeted therapeutics have now become standard care in gastrointestinal oncology. Beyond the molecular-targeted therapy options already approved in the European Union, there is a multitude of additional drugs and biomarkers available, which can also be used outside of formal approval (so-called off-label use). Examples of this are also discussed in this overview (e.g., HER2-targeted therapy for cholangiocarcinoma, the use of KRASG12C inhibitors, or checkpoint inhibition in microsatellite unstable ductal pancreatic carcinoma).The question whether the use of one of these therapeutics represents a possible treatment option for patients with gastrointestinal cancers is typically discussed in a Molecular Tumour Board after undergoing guideline-appropriate therapies.

Comprehensive review of pancreatic acinar cell carcinoma: epidemiology, diagnosis, molecular features and treatment

Pancreatic acinar cell carcinoma is a rare form (0.2-4.3%) of pancreatic neoplasm with unique clinical and molecular characteristics, which largely differ from pancreatic ductal adenocarcinoma. Pancreatic acinar cell carcinoma occurs more frequently in males and can occur in children. Serum lipase is elevated in 24-58% of patients with pancreatic acinar cell carcinoma. Pancreatic acinar cell carcinomas tend to be large at diagnosis (median tumour size: ~5 cm) and are frequently located in the pancreas head. Radiologically, pancreatic acinar cell carcinoma generally exhibits a solid appearance; however, necrosis, cystic changes and intratumoral haemorrhage can occur in larger lesions. Immunostaining is essential for the definitive diagnosis of pancreatic acinar cell carcinoma. Compared with pancreatic ductal adenocarcinoma, pancreatic acinar cell carcinoma has a more favourable prognosis. Although radical surgery is recommended for patients with pancreatic acinar cell carcinoma who do not have distant metastases, the recurrence rate is high. The effectiveness of adjuvant therapy for pancreatic acinar cell carcinoma is unclear. The response to FOLFIRINOX is generally favourable, and some patients achieve a complete response. Pancreatic acinar cell carcinoma has a different genomic profile compared with pancreatic ductal adenocarcinoma. Although genomic analyses have shown that pancreatic acinar cell carcinoma rarely has KRAS, TP53 and CDKN2A mutations, it has a higher prevalence of homologous recombination-related genes, including BRCA1/2 and ATM, than pancreatic ductal adenocarcinoma, suggesting high sensitivity to platinum-containing regimens and PARP inhibitors. Targeted therapies for genomic alternations are beneficial. Therefore, genetic testing is important for patients with pancreatic acinar cell carcinoma to choose the optimal therapeutic strategy.

Case report: Diverse immune responses in advanced pancreatic ductal adenocarcinoma treated with immune checkpoint inhibitor-based conversion therapies

Pancreatic ductal adenocarcinoma (PDAC) is often diagnosed at an advanced stage, presenting limited therapeutic options and a grim prognosis due to its aggressive nature. Despite ongoing exploration of various combination therapies, a standardized treatment approach after the first-line treatment progress remains elusive. This report details the cases of two patients with unresectable advanced PDAC who underwent distinct conversion treatment regimens involving immune checkpoint inhibitors (ICIs). Remarkably, both patients became eligible for surgery following different anti-PD-1 antibody-based conversion therapies, ultimately achieving R0 resection. In essence, our findings highlight the efficacy of the anti-PD-1 antibody combined with a tyrosine kinase inhibitor (TKI) regimen and chemotherapy alongside anti-PD-1 antibody as viable conversion therapies for preoperative advanced PDAC. Tumor immune microenvironment (TIME) analysis underscores the intratumoral and intertumoral heterogeneity observed in the postoperative immune landscape of surgical specimens. This insight contributes to a deeper understanding of the potential benefits of these conversion therapies in addressing the challenging landscape of advanced PDAC.

Primary resistance to immunotherapy in patients with a dMMR/MSI metastatic gastrointestinal cancer: who is at risk? An AGEO real-world study

BACKGROUND

The outstanding efficacy of immunotherapy in metastatic dMMR/MSI gastro-intestinal (GI) cancers has led to a rapid increase in the number of patients treated. However, 20-30% of patients experience primary resistance to immune checkpoint inhibitors (ICIPR) and need better characterization.

METHODS

This AGEO real-world study retrospectively analyzed the efficacy and safety of ICIs and identified clinical variables associated with ICIPR in patients with metastatic dMMR/MSI GI cancers treated with immunotherapy between 2015 and 2022.

RESULTS

399 patients were included, 284 with colorectal cancer (CRC) and 115 with non-CRC, mostly treated by an anti-PD(L)1 (88.0%). PFS at 24 months was 55.8% (95CI [50.8-61.2]) and OS at 48 months was 59.1% (95CI [53.0-65.9]). ORR was 51.0%, and 25.1% of patients were ICIPR. There was no statistical difference in ORR, DCR, PFS, or OS between CRC and non-CRC groups. In multivariable analysis, ICIPR was associated with ECOG-PS ≥ 2 (OR = 3.36), liver metastases (OR = 2.19), peritoneal metastases (OR = 2.00), ≥1 previous line of treatment (OR = 1.83), and age≤50 years old (OR = 1.76).

CONCLUSION

These five clinical factors associated with primary resistance to ICIs should be considered by physicians to guide treatment choice in GI dMMR/MSI metastatic cancer patients.

Molecular diagnostics of hepatobiliary and pancreatic neoplasias

Neoplasias of the hepatopancreatobiliary tract are growing in numbers, have the poorest prognosis of all major cancer entities, and thus represent a rising clinical problem. Their molecular diagnostic has dramatically improved, contributing to tumor subtyping, definition of malignancy, and uncovering cases with hereditary predisposition. Most of all, predictive molecular testing allows to identify cases amenable to treatment with the rising number of approved targeted drugs, immune-oncological treatment, and clinical trials. In this review, the current state of molecular testing and its contribution to clinical decision-making are outlined.

Precision medicine for KRAS wild-type pancreatic adenocarcinomas

BACKGROUND

KRAS mutation is the most common molecular alteration in pancreatic adenocarcinoma (PDAC), and around 10% of patients harbor KRAS wild-type tumors (KRASWT).

METHODS

A retrospective chart review of clinical/molecular data was performed including all PDAC patients with a determined KRAS status (tumor molecular profiling on tissue or liquid biopsy).

RESULTS

342 patients were included with 54 KRASWT PDAC (16%) compared to 288 patients with KRASm PDAC. Median age was 61 years [IQR:54.0;67.0] and 164 pts (48%) were female. At diagnosis, KRASWT patients (63%) were more frequently diagnosed at a non-metastatic stage compared to KRASm patients (41%) (p = 0.003). Regarding metastatic sites, liver was less frequent in KRASWT (39%, p < 0.0001). Median overall survival (mOS) from initial diagnosis was significantly higher in the KRASWT group compared to KRASm (50.8 months, CI95% [32.0-NR] vs 21.1 months, CI95% [18.9-23.4] (p < 0.004 after adjustment on age, ECOG and stage at diagnosis). In first-line systemic treatment, (mostly FOLFIRINOX) progression-free survival (PFS) was also higher in KRASWT. Based on ESCAT classification, a putative actionable alteration (ESCAT I-III) was identified in 19 (36%) KRASWT pts and 46 (16%) KRASm patients (p < 0.0001) with more alterations in FGFR2, BRAF(V600E), NRTK and more MSI tumors. KRASWT harbored also fewer alterations in TP53, CDKN2A, and SMAD4. 12 KRASWT patients received a molecularly-matched treatment with clinical benefit and improved outcomes compared to KRASm patients.

CONCLUSIONS

KRASWT patients display distinct disease characteristics and outcomes with prolonged overall survival. KRASWT patients also harbor more actionable molecular alterations, leading to higher survival rates after receiving molecularly matched treatments.

The immunological landscape in pancreatic ductal adenocarcinoma and overcoming resistance to immunotherapy

Pancreatic ductal adenocarcinoma is associated with a poor prognosis and there are few treatment options. The development of immunotherapy in pancreatic ductal adenocarcinoma has been difficult, and immune checkpoint inhibitors are only effective in a very small subset of patients. Most obstacles for treatment have been related to intertumoural and intratumoural heterogeneity, the composition of tumour stroma, and crosstalk with cancer cells. Improved molecular characterisation of pancreatic ductal adenocarcinoma and a better understanding of its microenvironment have paved the way for novel immunotherapy strategies, including the identification of predictive biomarkers, the development of rational combinations to optimise effectiveness, and the targeting of new mechanisms. Future immunotherapy strategies should consider individual characteristics to move beyond the traditional immune targets and circumvent the resistance to therapies that have been developed so far.

Neoadjuvant Immunotherapy for Localized Pancreatic Cancer: Challenges and Early Results

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal disease due to its late presentation and tendency to recur early even after optimal surgical resection. Currently, there are limited options for effective systemic therapy. In addition, PDAC typically generates an immune-suppressive tumor microenvironment; trials of immunotherapy in metastatic PDAC have yielded disappointing results. There is considerable interest in using immunotherapy approaches in the neoadjuvant setting in order to prime the immune system to detect and prevent micrometastatic disease and recurrence. A scoping review was conducted to identify published and ongoing trials utilizing preoperative immunotherapy. In total, 9 published trials and 27 ongoing trials were identified. The published trials included neoadjuvant immune checkpoint inhibitors, cancer vaccines, and other immune-modulating agents that target mechanisms distinct from that of immune checkpoint inhibition. Most of these are early phase trials which suggest improvements in disease-free and overall survival when combined with standard neoadjuvant therapy. Ongoing trials are exploring various combinations of these agents with each other and with chemotherapy and/or radiation. Rational combination immunotherapy in addition to standard neoadjuvant therapy has the potential to improve outcomes in PDAC, but further clinical trials are needed, particularly those which utilize an adaptive trial design.

Efficacy of Immune Checkpoint Inhibition and Cytotoxic Chemotherapy in Mismatch Repair-Deficient and Microsatellite Instability-High Pancreatic Cancer: Mayo Clinic Experience

PURPOSE

Pancreatic cancer (PC) carries a poor prognosis with high rates of unresectable/metastatic disease at diagnosis, recurrence after resection, and few systemic therapy options. Deficient mismatch repair (dMMR)/high microsatellite instability (MSI-H) PCs demonstrated uncharacteristically poor outcomes in KEYNOTE-158, evaluating pembrolizumab in MSI-H solid tumors. Our study aggregates the Mayo Clinic experience with dMMR/MSI-H PCs, characterizing the clinical, molecular, and treatment response patterns with a focus on response to immune checkpoint inhibitors (ICIs).

METHODS

Retrospective data were collected from the electronic medical record from December 2009 to February 2023. Patients were included if they had a pathologically confirmed pancreatic malignancy and had (1) deficient expression of mismatch repair (MMR) proteins by tumor immunohistochemistry, (2) pathogenic mutation of MMR genes on genomic sequencing, and/or (3) MSI-H by polymerase chain reaction.

RESULTS

Thirty-two patients were identified for inclusion, with all stages of disease represented. Sixteen of these patients underwent surgery or chemoradiotherapy. Of these patients, uncharacteristically favorable responses were seen, with a recurrence rate of only 19% (n = 3) despite a median follow-up of 25 months. In the palliative setting, excellent responses to ICI were seen, with overall response rate (ORR) of 75% (20% complete response). Median time to disease progression was not reached. Response rates to cytotoxic chemotherapy in the palliative setting were poor, with 30% ORR and median time to progression of 4 months. We observed a high rate of discrepancy between MMR and MSI testing methods, representing 19% of the entire cohort and 26% of evaluable cases.

CONCLUSION

Our data argue for the preferential use of ICI over cytotoxic chemotherapy in any patient with dMMR/MSI-H PC requiring systemic therapy, including in the metastatic and adjuvant/neoadjuvant settings.