Outcomes of lung metastasis from pancreatic cancer: A nationwide multicenter analysis

The impact of metastatic sites on survival Rates and predictors of extended survival in patients with metastatic pancreatic cancer

BACKGROUND OBJECTIVES

The aim of this study was to determine the role of site-specific metastatic patterns over time and assess factors associated with extended survival in metastatic PDAC. Half of all patients with pancreatic ductal adenocarcinoma (PDAC) present with metastatic disease. The site of metastasis plays a crucial role in clinical decision making due to its prognostic value.

METHODS

We examined 56,757 stage-IV PDAC patients from the National Cancer Database (2016-2019), categorizing them by metastatic site: multiple, liver, lung, brain, bone, carcinomatosis, or other. The site-specific prognostic value was assessed using log-rank tests while time-varying effects were assessed by Aalen's linear hazards model. Factors associated with extended survival (>3years) were assessed with logistic regression.

RESULTS

Median overall survival (mOS) in patients with distant lymph node-only metastases (9.0 months) and lung-only metastases (8.1 months) was significantly longer than in patients with liver-only metastases (4.6 months, p < 0.001). However, after six months, the metastatic site lost prognostic value. Logistic regression identified extended survivors (3.6 %) as more likely to be younger, Hispanic, privately insured, Charlson-index <2, having received chemotherapy, or having undergone primary or distant site surgery (all p < 0.001).

CONCLUSION

While synchronous liver metastases are associated with worse outcomes than lung-only and lymph node-only metastases, this predictive value is diminished after six months. Therefore, treatment decisions beyond this time should not primarily depend on the metastatic site. Extended survival is possible in a small subset of patients with favorable tumor biology and good conditional status, who are more likely to undergo aggressive therapies.

Surgery for Oligometastatic Pancreatic Cancer: Defining Biologic Resectability

Pancreatic ductal adenocarcinoma (PDAC) is most often metastatic at diagnosis. As systemic therapy continues to improve alongside advanced surgical techniques, the focus has shifted toward defining biologic, rather than technical, resectability. Several centers have reported metastasectomy for oligometastatic PDAC, yet the indications and potential benefits remain unclear. In this review, we attempt to define oligometastatic disease in PDAC and to explore the rationale for metastasectomy. We evaluate the existing evidence for metastasectomy in liver, peritoneum, and lung individually, assessing the safety and oncologic outcomes for each. Furthermore, we explore contemporary biomarkers of biological resectability in oligometastatic PDAC, including radiographic findings, biochemical markers (such as CA 19-9 and CEA), inflammatory markers (including neutrophil-to-lymphocyte ratio, C-reactive protein, and scoring indices), and liquid biopsy techniques. With careful consideration of existing data, we explore the concept of biologic resectability in guiding patient selection for metastasectomy in PDAC.

Meta-analysis of survival after pulmonary resection for isolated metachronous pancreatic cancer metastasis: a promising, albeit infrequent, approach

BACKGROUND

To evaluate survival outcomes of pulmonary resection for isolated metachronous pancreatic cancer metastasis.

METHODS

A systematic search of electronic data sources and reference lists were conducted. Proportion meta-analysis model was constructed to quantify 1- to 5-year survival after pulmonary resection for isolated metachronous pancreatic cancer metastasis. Random-effects modelling was applied to calculate pooled outcome data.

RESULTS

Twenty-four retrospective studies were included reporting a total of 168 patients who underwent pulmonary resection for isolated pancreatic cancer metastasis. The nature of the index pancreatic surgery included 65% pancreaticoduodenectomies, 17.5% distal pancreatectomies, 0.5% total pancreatectomy, and 17% unspecified. Adjuvant chemotherapy was given to 88% of the patients. The median disease-free interval was 35 (8-96) months. The type of pulmonary resection included 54% wedge resections, 26% lobectomies, 4% segmentectomies, 1% pneumonectomies, and 15% unspecified. Pulmonary resection was associated with 1-year survival of 91.1% (95% CI 86.6%-95.5%), 2-year survival of 77.5% (95% CI 68.9%-86.0%), 3-year survival of 65.0% (95% CI 50.7%-79.3%), 4-year survival of 52.0% (95% CI 37.2%-66.9%), and 5-year survival of 37.0% (95% CI 25.0%-49.1%).

CONCLUSION

Pulmonary resection for isolated pancreatic cancer metastasis is associated with acceptable overall patient survival. We recommend selective pulmonary resection for isolated pulmonary metastasis from pancreatic cancer. Our findings may encourage conduction of better-quality studies in this context to help establishment of definitive treatment strategies.

Oncological Outcomes and Patterns of Recurrence after the Surgical Resection of an Invasive Intraductal Papillary Mucinous Neoplasm versus Primary Pancreatic Ductal Adenocarcinoma: An Analysis from the German Cancer Registry Group of the Society of German Tumor Centers

BACKGROUND

Intraductal papillary mucinous neoplasms (IPMNs) are premalignant cystic neoplasms of the pancreas (CNPs), which can progress to invasive IPMN and pancreatic cancer. The available literature has shown controversial results regarding prognosis and clinical outcomes after the resection of invasive IPMN.

AIMS

This study aims to characterize the oncologic outcomes and metastatic progression pattern after the resection of non-metastatic invasive IPMN.

METHODS

Data were obtained from 24 clinical cancer registries participating in the German Cancer Registry Group of the Society of German Tumor Centers (ADT). Patients with invasive IPMN (n = 217) as well as PDAC (n = 5794) between 2000 and 2021 were included and compared regarding oncological outcomes.

RESULTS

Invasive IPMN was significantly smaller in size (p < 0.001) and of a lower tumor grade (p < 0.001), with fewer lymph node metastases (p < 0.001), lymphangiosis (p < 0.001), and consequently a higher R0 resection rate (88 vs. 74%) compared to PDAC. Moreover, invasive IPMN was associated with fewer local (11 vs. 15%) and distant recurrences (29 vs. 46%) and metastasized more frequently in the lungs only (26% vs. 14%). Invasive IPMN was associated with a longer median OS (29 vs. 19 months) and DFS (31 vs. 15 months) compared to PDAC and stayed independently prognostic in multivariable analyses. These survival differences were most pronounced in early tumor stages. Interestingly, postoperative chemotherapy was not associated with improved overall survival in surgically resected invasive IPMN.

CONCLUSIONS

Invasive IPMN is a rare pancreatic entity with increasing incidence in Germany. It is associated with favorable histopathological features at the time of resection and longer OS and DFS compared to PDAC, particularly before the locoregional spread has occurred. Invasive IPMNs are associated with lung-only metastasis. The benefit of postoperative chemotherapy after the resection of invasive IPMN remains uncertain.

REDISCOVER guidelines for borderline-resectable and locally advanced pancreatic cancer: management algorithm, unanswered questions, and future perspectives

The REDISCOVER guidelines present 34 recommendations for the selection and perioperative care of borderline-resectable (BR-PDAC) and locally advanced ductal adenocarcinoma of the pancreas (LA-PDAC). These guidelines represent a significant shift from previous approaches, prioritizing tumor biology over anatomical features as the primary indication for resection. Condensed herein, they provide a practical management algorithm for clinical practice. However, the guidelines also highlight the need to redefine LA-PDAC to align with modern treatment strategies and to solve some contradictions within the current definition, such as grouping "difficult" and "impossible" to resect tumors together. Furthermore, the REDISCOVER guidelines highlight several areas requiring urgent research. These include the resection of the superior mesenteric artery, the management strategies for patients with LA-PDAC who are fit for surgery but unable to receive multi-agent neoadjuvant chemotherapy, the approach to patients with LA-PDAC who are fit for surgery but demonstrate high serum Ca 19.9 levels even after neoadjuvant treatment, and the optimal timing and number of chemotherapy cycles prior to surgery. Additionally, the role of primary chemoradiotherapy versus chemotherapy alone in LA-PDAC, the timing of surgical resection post-neoadjuvant/primary chemoradiotherapy, the efficacy of ablation therapies, and the management of oligometastasis in patients with LA-PDAC warrant investigation. Given the limited evidence for many issues, refining existing management strategies is imperative. The establishment of the REDISCOVER registry ( https://rediscover.unipi.it/ ) offers promise of a unified research platform to advance understanding and improve the management of BR-PDAC and LA-PDAC.

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.

Clinical benefits of pulmonary resection for lung metastases from pancreatic cancer

PURPOSE

Systemic chemotherapy is generally used for metastatic pancreatic cancer; however, pulmonary resection may be a treatment option for lung oligometastases from pancreatic cancer. The current study aimed to clarify the oncological outcomes and clinical benefits of pulmonary resection for lung metastases.

METHODS

Of 510 patients who underwent pancreatic resection for pancreatic cancer, 44 patients with recurrence of isolated lung metastases and one patient with simultaneous lung metastases were evaluated.

RESULTS

Of the 45 patients, 20 patients were selected as candidates for pulmonary resection based on clinical factors such as recurrence-free interval (RFI) from pancreatectomy to lung metastases, number of lung metastases, and serum CA19-9 level. The post-recurrent survival of patients with pulmonary resection was significantly better than that of patients without pulmonary resection. Fourteen of the 20 patients with pulmonary resection developed tumor recurrence with a median disease-free survival (DFS) of 15 months. Univariate analyses revealed that an RFI from pancreatectomy to lung metastases of ≥28 months was associated with better DFS after pulmonary resection. Of the 14 patients with an RFI of ≥28 months, pulmonary resection resulted in prolonged chemotherapy-free interval in 12 patients. Furthermore, repeat pulmonary resection for recurrent tumors after pulmonary resection led to further cancer-free interval in some cases.

CONCLUSIONS

Although many patients had tumor recurrence after pulmonary resection, pulmonary resection for lung metastases from pancreatic cancer may provide prolonged cancer-free interval without the need for chemotherapy. Pulmonary resection should be performed for the patients with a long RFI from pancreatectomy to lung metastases.

Outcomes of lung oligometastasis in pancreatic cancer

OBJECTIVE

Pancreatic cancer with lung oligometastasis may have favourable overall survival. The aim of this study was to evaluate outcomes of pancreatic cancer with lung oligometastases including both synchronous and metachronous metastases.

METHODS

Consecutive pancreatic cancer patients with lung metastasis treated at our institution between February 2015 and December 2021 were identified from our prospectively maintained database. Clinical characteristics and outcomes were compared and analysed according to the extent of lung metastases. Predictors for overall survival were analysed using the Cox proportional hazards model.

RESULTS

A totoal of 171 patients were included (oligometastasis/polymetastasis/multi-organ metastasis: 34/50/87). Patients with oligometastases were more likely to undergo surgical resection (41% vs. 0% vs. 2%) and showed a longer median overall survival (41.3 vs. 17.6 vs. 13.1 months) compared with those with other types of metastases. Oligometastasis (hazard ratio, 0.43; 95% confidence interval, 0.24-0.76; P = 0.004) was identified as an independent factor predicting favourable overall survival in patients with lung-only metastasis. Disease status (synchronous vs. metachronous) was not associated with survival in patients with oligometastasis (29.4 vs. 41.3 months, P = 0.527) and polymetastasis (17.9 vs. 16.7 months, P = 0.545). Selected patients who underwent surgical resection showed a median overall survival of 52.7 months.

CONCLUSIONS

Patients with lung oligometastases presented a favourable prognosis. Surgical resection in selected patients was associated with a long median overall survival.

Defining oligometastatic pancreatic cancer: a systematic review and critical synthesis of consensus

BACKGROUND

Small retrospective series suggest that local consolidative treatment (LCT) may improve survival in oligometastatic pancreatic ductal adenocarcinoma (PDAC). However, no uniform definition of oligometastatic disease (OMD) in PDAC exists; this impedes meaningful conclusions.

PATIENTS AND METHODS

A systematic literature search using PubMed, Web of Science, and Cochrane CENTRAL registries for studies and protocols reporting on definitions and/or LCT of OMD in PDAC was performed. The primary endpoint was the definition of OMD. Levels of agreement were categorized as consensus (≥75% agreement between studies), fair agreement (50%-74%), and absent/poor agreement (<50%).

RESULTS

After screening of 5374 abstracts, the full text of 218 studies was assessed, of which 76 were included in the qualitative synthesis. The majority of studies were retrospective (n = 66, 87%), two were prospective studies and eight were study protocols. Studies investigated mostly liver (n = 38, 51%) and lung metastases (n = 15, 20%). Across studies, less than one-half (n = 32, 42%) reported a definition of OMD, while 44 (58%) did not. Involvement was limited to a single organ (consensus). Additional criteria for defining OMD were the number of lesions (consensus), metastatic site (poor agreement), metastatic size (poor agreement), treatment possibilities (poor agreement), and biomarker response (poor agreement). Liver OMD could involve three or fewer lesions (consensus) and synchronous disease (fair agreement), while lung metastases could involve two or fewer lesions and metachronous disease (consensus). The large majority of studies were at a high risk of bias or did not include any control groups.

CONCLUSION

Definitions of OMD were not used or varied widely between studies hampering across-study comparability and highlighting an unmet need for a consensus. The present study is part of a multistep process that aims to develop an interdisciplinary consensus on OMD in pancreatic cancer.

Efficacy of staging laparoscopy for resectable pancreatic cancer on imaging and the therapeutic effect of systemic chemotherapy for positive peritoneal cytology

BACKGROUND

The frequency and prognosis of positive peritoneal washing cytology (CY1) in resectable pancreatic ductal adenocarcinoma (R-PDAC) remains unclear. The objective of this study was to identify the clinical implications of CY1 in R-PDAC and staging laparoscopy (SL).

METHODS

We retrospectively analyzed 115 consecutive patients with R-PDAC who underwent SL between 2018 and 2022. Patients with negative cytology (CY0) received radical surgery after neoadjuvant chemotherapy, while CY1 patients received systemic chemotherapy and were continuously evaluated for cytology.

RESULTS

Of the 115 patients, 84 had no distant metastatic factors, 22 had only CY1, and nine had distant metastasis. Multivariate logistic regression revealed that larger tumor size was an independent predictor of the presence of any distant metastatic factor (OR: 6.30, p = .002). Patients with CY1 showed a significantly better prognosis than patients with distant metastasis (MST: 24.6 vs. 18.9 months, p = .040). A total of 11 CY1 patients were successfully converted to CY-negative, and seven underwent conversion surgery. There was no significant difference in overall survival between patients with CY0 and those converted to CY-negative.

CONCLUSION

SL is effective even for R-PDAC. The prognosis of CY1 patients converted to CY-negative is expected to be similar to that of CY0 patients.

Outcomes of surgical resection for pulmonary metastasis from pancreatic cancer

PURPOSE

As the number of long-term survivors of pancreatic cancer is expected to increase thanks to recent advances in multidisciplinary treatment and earlier diagnoses of pancreatic cancer, we are likely to encounter more cases of postoperative pulmonary nodules. We analyzed the clinical course and prognosis of resection of pulmonary metastases from pancreatic cancer to clarify the prognostic implication of pulmonary metastasectomy for pancreatic cancer.

METHOD

We retrospectively analyzed 35 patients who underwent resection of lung metastases after pancreatic cancer surgery. Short- and long-term outcomes and factors associated with the prognosis were analyzed.

RESULTS

The observation period was 20 (range, 1-101) months, with 3- and 5-year survival rates of 88.3% and 64.5% from pancreatectomy and 44.1% and 28.3% from lung resection, respectively. A univariate analysis revealed that a period from pancreatic cancer resection to pulmonary nodule shadow detection of < 15 months was associated with a significantly lower overall survival from pancreatic resection than a longer period. Conversely, histological type, stage, size of lung metastases, and resection technique were not associated with the overall survival.

CONCLUSION

A long-term prognosis may be expected in some cases with a disease-free interval of ≥ 15 months. Our findings suggest that the disease-free interval may influence the prognosis.

Prognostic factor in patient with recurrent pancreatic adenocarcinoma

PURPOSE

To elucidate prognostic factors for post-recurrence survival in patients with pancreatic ductal adenocarcinoma (PDAC).

METHODS

Patients who underwent curative-intent surgery for PDAC between January 2014 and May 2020 were identified. Among them, patients who had postoperative recurrences and received chemotherapy were retrospectively investigated. Independent prognostic factors for survival after recurrence were investigated using multivariate analyses. Eligible patients were divided into two groups according to the presence or absence of the identified prognostic factors, and survival times after recurrence were compared.

RESULTS

Eighty-four patients with recurrent PDAC were included. Multivariate analysis showed that red blood cell (RBC) transfusion (HR, 2.80; p = 0.0051), low albumin level (HR, 1.84; p = 0.0402), and high carbohydrate antigen 19-9 (CA19-9) level at recurrence (HR, 2.11; p = 0.0258) were significant predictors of shorter survival after recurrence. The median survival times after recurrence in the transfusion and non-transfusion groups were 5.5 vs. 18.1 months (p < 0.0001), respectively; those in the low and normal albumin groups were 10.1 vs. 18.7 months (p = 0.0049), and those in the high and normal CA19-9 groups were 11.5 vs. 22.6 months (p = 0.0023), respectively.

CONCLUSIONS

RBC transfusion, low albumin, and high CA19-9 levels at recurrence negatively affected survival after recurrence in patients with PDAC.

Prognostic impact of lung recurrence in patients with biliary tract cancer

PURPOSE

This study aimed to evaluate the prognostic impact of the initial recurrence site following resection for biliary tract carcinoma (BTC), focusing on lung recurrence.

METHODS

The clinical data of patients with recurrent BTC who underwent curative intent surgery between March 2009 and December 2021 were retrospectively analyzed. The prognosis of patients with recurrent BTC was investigated in each recurrence site. Eligible patients were classified into two groups according to lung or non-lung recurrence. Clinicopathological factors, survival after recurrence, and overall survival were compared between the two groups. Independent factors associated with survival after recurrence were investigated using multivariate analysis.

RESULTS

Of 119 patients, the initial recurrence site was local in 26 (21.8%) patients, liver in 19 (16.8%), peritoneum in 14 (11.8%), lymph node in 12 (10.1%), lung in 11 (9.2%), multiple organs in 32 (26.9%), and others in 5 (4.2%). The survival period after recurrence in patients with lung recurrence was significantly longer than those in patients with other six recurrence patterns. The median survival after recurrence was 34.3 and 9.3 months in lung recurrence and non-lung recurrence groups, respectively (p < 0.0001); that after initial surgery was 50.8 and 26.4 months, respectively (p = 0.0383). Multivariate analysis revealed that lung recurrence and normal albumin level at recurrence were independently associated with survival after recurrence (Hazard Ratio (HR), 0.291; p = 0.0128; HR, 0.476; p = 0.00126, respectively).

CONCLUSIONS

Survival period after recurrence was significantly longer in patients with lung recurrence.

p53 inhibitor iASPP is an unexpected suppressor of KRAS and inflammation-driven pancreatic cancer

Oncogenic KRAS activation, inflammation and p53 mutation are key drivers of pancreatic cancer (PC) development. Here we report iASPP, an inhibitor of p53, as a paradoxical suppressor of inflammation and oncogenic KRAS^G12D-driven PC tumorigenesis. iASPP suppresses PC onset driven by KRAS^G12D alone or KRAS^G12D in combination with mutant p53^R172H. iASPP deletion limits acinar-to-ductal metaplasia (ADM) in vitro but accelerates inflammation and KRAS^G12D-induced ADM, pancreatitis and PC tumorigenesis in vivo. KRAS^G12D/iASPP^Δ8/Δ8 tumours are well-differentiated classical PCs and their derivative cell lines form subcutaneous tumours in syngeneic and nude mice. Transcriptomically, either iASPP deletion or p53 mutation in the KRAS^G12D background altered the expression of an extensively overlapping gene set, comprised primarily of NF-κB and AP1-regulated inflammatory genes. All these identify iASPP as a suppressor of inflammation and a p53-independent oncosuppressor of PC tumorigenesis.

Neoadjuvant therapy for pancreatic cancer

Patients with localized pancreatic ductal adenocarcinoma (PDAC) are best treated with surgical resection of the primary tumour and systemic chemotherapy, which provides considerably longer overall survival (OS) durations than either modality alone. Regardless, most patients will have disease relapse owing to micrometastatic disease. Although currently a matter of some debate, considerable research interest has been focused on the role of neoadjuvant therapy for all forms of resectable PDAC. Whilst adjuvant combination chemotherapy remains the standard of care for patients with resectable PDAC, neoadjuvant chemotherapy seems to improve OS without necessarily increasing the resection rate in those with borderline-resectable disease. Furthermore, around 20% of patients with unresectable non-metastatic PDAC might undergo resection following 4-6 months of induction combination chemotherapy with or without radiotherapy, even in the absence of a clear radiological response, leading to improved OS outcomes in this group. Distinct molecular and biological responses to different types of therapies need to be better understood in order to enable the optimal sequencing of specific treatment modalities to further improve OS. In this Review, we describe current treatment strategies for the various clinical stages of PDAC and discuss developments that are likely to determine the optimal sequence of multimodality therapies by integrating the fundamental clinical and molecular features of the cancer.

Essential updates 2021/2022: Surgical outcomes of oligometastasis in pancreatic ductal adenocarcinoma

Oligometastatic disease has been proposed as an intermediate state between localized and polymetastatic disease that can benefit from multimodal treatment, including surgery. There is a growing concern about performing surgery for oligometastatic pancreatic ductal adenocarcinoma, although there is still little evidence. We reviewed articles published between 2021 and 2022, focusing mainly on surgical outcomes. Furthermore, we summarized the current status of surgery in the multidisciplinary treatment of oligometastatic pancreatic cancer and discuss future perspectives. In liver oligometastasis, multimodal treatment including surgery achieved favorable long-term survival, especially in patients with good responses to preoperative chemotherapy, with a median survival time from 25.5 to 54.6 months. In addition, the data from the National Cancer Database in the United States showed that patients who underwent surgery for oligometastatic liver metastases had a significantly longer overall survival than those who received chemotherapy alone. Prognostic biomarkers were identified, including carbohydrate antigen 19-9 (CA19-9) levels at diagnosis and preoperative chemotherapy with normalization of CA19-9 levels or favorable radiological response. Patients with lung oligometastasis had a more favorable long-term prognosis than those with other recurrence sites, and the updated literature further confirmed the previous studies. Overall survival was favorable, with 84 months after initial surgery and 29.2 months after metastasectomy, and a 5-year survival rate of 60.6% was also reported. In peritoneal oligometastasis, the results of conversion surgery after good responses to preoperative treatment with intraperitoneal therapy or systematic chemotherapy were reported, and the conversion rate and long-term prognosis were favorable. There is a growing concern about performing surgery for oligometastatic pancreatic ductal adenocarcinoma. We reviewed articles published between 2021 and 2022, focusing mainly on surgical outcomes. Furthermore, we summarize the current status of surgery in multidisciplinary treatment of oligometastatic pancreatic cancer and discuss future perspectives.

Refining the Treatment of Pancreatic Cancer From Big Data to Improved Individual Survival

Pancreatic cancer is one of the most lethal cancers worldwide, most notably in Europe and North America. Great strides have been made in combining the most effective conventional therapies to improve survival at least in the short and medium term. The start of treatment can only be made once a diagnosis is made, which at this point, the tumor volume is already very high in the primary cancer and systemically. If caught at the earliest opportunity (in circa 20% patients) surgical resection of the primary followed by combination chemotherapy can achieve 5-year overall survival rates of 30%-50%. A delay in detection of even a few months after symptom onset will result in the tumor having only borderline resectabilty (in 20%-30% of patients), in which case the best survival is achieved by using short-course chemotherapy before tumor resection as well as adjuvant chemotherapy. Once metastases become visible (in 40%-60% of patients), cure is not possible, palliative cytotoxics only being able to prolong life by few months. Even in apparently successful therapy in resected and borderline resectable patients, the recurrence rate is very high. Considerable efforts to understand the nature of pancreatic cancer through large-scale genomics, transcriptomics, and digital profiling, combined with functional preclinical models, using genetically engineered mouse models and patient derived organoids, have identified the critical role of the tumor microenvironment in determining the nature of chemo- and immuno-resistance. This functional understanding has powered fresh and exciting approaches for the treatment of this cancer.

Risk factors and survival prediction of pancreatic cancer with lung metastases: A population-based study

Background

The risk and prognosis of pancreatic cancer with lung metastasis (PCLM) are not well-defined. Thus, this study aimed to identify the risk and prognostic factors for these patients, and establish predictive nomogram models.

Methods

Patients diagnosed with PCLM between 2010 and 2016 were identified from the Surveillance, Epidemiology, and End Results (SEER) database. Independent risk factors and prognostic factors were identified using logistic regression and Cox regression analyses. Nomograms were constructed to predict the risk and survival of PCLM, and the area under the curve (AUC), C-index, and calibration curve were used to determine the predictive accuracy and discriminability of the established nomogram, while the decision curve analysis was used to confirm the clinical effectiveness.

Results

A total of 11287 cases with complete information were included; 601 (5.3%) patients with PC had lung metastases. Multivariable logistic analysis demonstrated that primary site, histological subtype, and brain, bone, and liver metastases were independent risk factors for lung metastases. We constructed a risk prediction nomogram model for the development of lung metastases among PC patients. The c-index of the established diagnostic nomogram was 0.786 (95%CI 0.726-0.846). Multivariable Cox regression analysis demonstrated that primary site, liver metastases, surgery, and chemotherapy were independent prognostic factors for both overall survival (OS) and cancer-specific survival (CSS), while bone metastases were independent prognostic factors for CSS. The C-indices for the OS and CSS prediction nomograms were 0.76 (95% CI 0.74-0.78) and 0.76 (95% CI 0.74-0.78), respectively. Based on the AUC of the receiver operating characteristic (ROC) analysis, calibration plots, and decision curve analysis (DCA), we concluded that the risk and prognosis model of PCBM exhibits excellent performance.

Conclusions

The present study identified the risk and prognostic factors of PCLM and further established nomograms, which can help clinicians effectively identify high-risk patients and predict their clinical outcomes.

NLRP3 activation in tumor-associated macrophages enhances lung metastasis of pancreatic ductal adenocarcinoma

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is the most common type of pancreatic cancer and is highly malignant due to its late diagnosis and early metastasis. Lung metastasis of PDAC occurs in a significant number of diagnosed patients and represents high severity of disease and poor clinical outcome. However, the molecular regulation of lung metastasis of PDAC is still not fully understood. Tumor-associated macrophages (TAMs) have recently been found to play an important role in cancer initiation, proliferation, progression, and metastasis. The proliferation, differentiation, and polarization of macrophages has been shown to be regulated by interleukin 1β (IL-1β), which is generated by NLR family pyrin domain containing 3 (NLRP3)-induced formation of inflammasome. Herein we investigated whether NLRP3 plays a role in lung metastasis of PDAC through regulation of macrophage polarization.

METHODS

Gene profiles for NLRP3 (+/+) and NLRP3 (-/-) macrophages obtained from the Gene Expression Omnibus (GEO) public database were compared and analyzed for altered genes related to macrophage polarization. The regulation of macrophage polarization by NLRP3 was examined in a coculture system with naïve NLRP3 (+/+) or NLRP3 (-/-) macrophages and PDAC cells. Cell growth was analyzed by a Cell Counting Kit-8 (CCK-8) assay. Cell invasiveness and migratory potential were analyzed by transwell cell invasion assay and cell migration assay, respectively. PDAC formation and lung metastasis were analyzed in a mouse model of PDAC with and without NLRP3 knockout.

RESULTS

GEO database analysis revealed significant alteration in genes that regulate macrophage polarization in NLRP3-depleted macrophages. NLRP3-depletion in macrophages seemed to favor an M1/M2b polarization. In vitro, the presence of NLRP3 in macrophages led to M2a/c/d TAM-like polarization when they were cocultured with PDAC cells. Conversely, NLRP3 depletion in macrophages led to M1/M2b polarization when they were cocultured with PDAC cells. NLRP3-depletion significantly inhibited tumor growth and stage progression in a mouse model of PDAC and significantly reduced the occurrence of lung metastasis.

CONCLUSIONS

Our results suggested that NLRP3 activation in TAM enhanced lung metastasis of PDAC through regulation of TAM polarization.