The past, present, and future status of multimodality treatment for resectable/borderline resectable pancreatic ductal adenocarcinoma

Prognostic significance of occult vertebral fracture in patients undergoing pancreatic resection for pancreatic cancer

OBJECTIVE

The prognostic impact of occult vertebral fracture (OVF) in patients with malignancies is a new cutting edge in cancer research. This study was performed to analyze the prognostic impact of OVF after surgery for pancreatic cancer.

METHODS

This study involved 200 patients who underwent surgical treatment of pancreatic ductal adenocarcinoma. OVF was diagnosed by quantitative measurement using preoperative sagittal computed tomography image reconstruction from the 11th thoracic vertebra to the 5th lumbar vertebra.

RESULTS

OVF was diagnosed in 65 (32.5 %) patients. The multivariate analyses showed that male sex (p = 0.01), osteopenia (p < 0.01), OVF (p < 0.01), a carbohydrate antigen 19-9 level of ≥400 U/mL (p < 0.01), advanced stage of cancer (p < 0.01), and non-adjuvant chemotherapy (p = 0.02) were independent risk factors for overall survival. An age of ≥74 years (p < 0.01) and obstructive jaundice (p = 0.03) were independent risk factors for OVF. Furthermore, the combination of OVF and osteopenia further worsened disease-free survival and overall survival compared with osteopenia or OVF alone (p < 0.01; respectively).

CONCLUSION

Evaluation of preoperative OVF might be a useful prognostic indicator for patients with pancreatic ductal adenocarcinoma.

The postoperative platelet-to-lymphocyte ratio predicts the outcome of patients undergoing pancreaticoduodenectomy for pancreatic head cancer

PURPOSE

The preoperative platelet-to-lymphocyte ratio (PLR) has been reported as an important prognostic index for pancreatic ductal adenocarcinoma (PDAC); however, the significance of the postoperative (post-op) PLR for this disease has not been elucidated.

METHODS

We analyzed data on 118 patients who underwent pancreaticoduodenectomy for pancreatic head PDAC, collected from a prospectively maintained database. The post-op PLR was obtained by dividing the platelet count after surgery by the lymphocyte count on post-op day (POD) 14. The patients were divided into two groups according to a post-op PLR of < 310 or ≥ 310. Survival data were analyzed.

RESULTS

A high post-op PLR was identified as a significant prognostic index on univariate analysis for disease-free survival (DFS) and overall survival (OS). The post-op PLR remained significant, along with tumor differentiation and adjuvant chemotherapy, on multivariate analysis for OS (hazard ratio = 2.077, 95% confidence interval: 1.220-3.537; p = 0.007). The post-op PLR was a significant independent prognostic index for poor DFS, along with tumor differentiation and lymphatic invasion, on multivariate analysis (hazard ratio = 1.678, 95% confidence interval: 1.056-2.667; p = 0.028).

CONCLUSIONS

The post-op PLR in patients with pancreatic head PDAC was an independent predictor of DFS and OS after elective resection.

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.

A scan of all coding region variants of the human genome, identifies 13q12.2-rs9579139 and 15q24.1-rs2277598 as novel risk loci for pancreatic ductal adenocarcinoma

Coding sequence variants comprise a small fraction of the germline genetic variability of the human genome. However, they often cause deleterious change in protein function and are therefore associated with pathogenic phenotypes. To identify novel pancreatic ductal adenocarcinoma (PDAC) risk loci, we carried out a complete scan of all common missense and synonymous SNPs and analysed them in a case-control study comprising four different populations, for a total of 14 538 PDAC cases and 190 657 controls. We observed a statistically significant association between 13q12.2-rs9581957-T and PDAC risk (P = 2.46 × 10-9), that is in linkage disequilibrium (LD) with a deleterious missense variant (rs9579139) of the URAD gene. Recent findings suggest that this gene is active in peroxisomes. Considering that peroxisomes have a key role as molecular scavengers, especially in eliminating reactive oxygen species, a malfunctioning URAD protein might expose the cell to a higher load of potentially DNA damaging molecules and therefore increase PDAC risk. The association was observed in individuals of European and Asian ethnicity. We also observed the association of the missense variant 15q24.1-rs2277598-T, that belongs to BBS4 gene, with increased PDAC risk (P = 1.53 × 10-6). rs2277598 is associated with body mass index and is in LD with diabetes susceptibility loci. In conclusion, we identified two missense variants associated with the risk of developing PDAC independently from the ethnicity highlighting the importance of conducting reanalysis of genome-wide association studies (GWASs) in light of functional data.

Survival impact of occult liver metastasis and peritoneal dissemination compared with radiologically defined distant organ metastasis in pancreatic ductal adenocarcinoma

BACKGROUND

Characteristics and prognoses of patients with occult metastases (OM) of pancreatic ductal adenocarcinoma (PDAC) compared with radiologically defined metastases (RM) have been rarely reported.

OBJECTIVE

We aimed to clarify the prognosis of OM compared with RM and to establish a treatment strategy for PDAC patients with OM.

METHODS

This single-institution, retrospective study evaluated patients with unresectable PDAC between 2008 and 2018. OM was defined as abdominal metastasis that was detected by staging laparoscopy or open laparotomy but not in the initial assessment of radiological images.

RESULTS

OM and RM were identified in 135 and 112 patients, respectively. Eastern Cooperative Oncology Group Performance Status (ECOG PS), neutrophil to lymphocyte ratio (NLR), tumor diameter, and rate of local unresectability were significantly lower in the OM group. Median overall survival (OS) of OM was significantly better than that of RM (13.0 vs 8.9 months, p < 0.001). In multivariate analysis of OS, ECOG PS ≥ 1 (HR 1.64, p = 0.009), NLR ≥5 (HR 1.97, p = 0.004), carbohydrate antigen (CA) 19-9 ≥1000 (HR 1.68, p = 0.001), tumor diameter ≥40 mm (HR 1.40, p = 0.027), conversion surgery (HR 0.12, p < 0.001), and multiple lines of chemotherapy (HR 0.38, p < 0.001) were independent predictors. However, type of metastasis (OM vs RM) not an independent predictor (HR 1.10, p = 0.590).

CONCLUSION

The prognosis of PDAC with OM was relatively better than that with RM, but general and nutritional statuses, primary tumor size and CA19-9, conversion surgery and multiple lines of chemotherapy were independent predictors but not tumor burden.

Impact of resection margin status on survival after operation for pancreatic head cancer with extrapancreatic nerve plexus invasion

BACKGROUND

Extrapancreatic nerve plexus (PL) invasion of pancreatic ductal adenocarcinoma (PDAC) is an important factor for determining resectability and surgical method. We sought to clarify the characteristics of PDAC with PL invasion and clinical impact of the resection margin status on prognosis for PDAC with PL invasion.

METHODS

A total of 242 patients with pancreatic head cancer who underwent pancreatectomy were evaluated. Clinicopathological data and patient survival were analyzed.

RESULTS

Pathological PL invasion was observed in 68 patients (28.1%). Patients with PL invasion had significantly shorter disease-free survival (DFS) and showed trends toward worse overall survival (OS) than those without PL invasion. While multivariate analysis revealed that PL invasion was not an independent prognostic factor, PL invasion was associated with extensive venous invasion and a high percentage of lymph node metastases, both of which were independent factors affecting DFS and OS. Among patients with PL invasion, there was no significant difference in DFS and OS between the R0 and R1 resection groups.

CONCLUSIONS

PL invasion is a common pathological feature of aggressive PDAC with high propensity for invasiveness and metastatic potential. The microscopic resection margin status may not affect the survival of pancreatic head cancer patients with PL invasion.

Venous resection for pancreatic cancer, a safe and feasible option? A systematic review and meta-analysis

BACKGROUND

In pancreatic ductal adenocarcinoma patients with suspected venous infiltration, a R0 resection is most of the time not possible without venous resection (VR). To investigate this special kind of patients, this meta-analysis was conducted to compare mortality, morbidity and long-term survival of pancreatic resections with (VR+) and without venous resection (VR-).

METHODS

A systematic search was performed in Embase, Pubmed and Web of Science. Studies which compared over twenty patients with VR + to VR-for PDAC with ≥1 year follow up were included. Articles including arterial resections were excluded. Statistical analysis was performed with the random effect Mantel-Haenszel test and inversed variance method. Individual patient data was compared with the log-rank test.

RESULTS

Following a review of 6403 papers by title and abstract and 166 by full text, a meta-analysis was conducted of 32 studies describing 2216 VR+ and 5380 VR-. There was significantly more post-pancreatectomy hemorrhage (6.5% vs. 5.6%), R1 resections (36.7% vs. 28.6%), N1 resections (70.3% vs. 66.8%) and tumors were significantly larger (34.6 mm vs. 32.8 mm) in patients with VR+. Of all VR + patients, 64.6% had true pathological venous infiltration. The 90-day mortality, individual patient data for overall survival and pooled multivariate hazard ratio for overall survival were similar.

CONCLUSION

VR is a safe and feasible option in patients with pancreatic cancer and suspicion of venous involvement, since VR during pancreatic surgery has comparable overall survival and complication rates.

A simple risk score for detecting radiological occult metastasis in patients with resectable or borderline resectable pancreatic ductal adenocarcinoma

BACKGROUND

We advocated carbohydrate antigen (CA) 19-9 ≥ 150 U/mL and tumor size ≥30 mm as "high-risk markers" for predicting unresectability among patients with radiologically resectable (R) or borderline resectable (BR) pancreatic ductal adenocarcinoma (PDAC). The main aim is to establish a risk scoring system for occult abdominal metastasis (OAM) in R/BR PDAC.

METHODS

Predictors of OAM were investigated retrospectively in an experiment cohort from 2006 to 2018. The proposed risk scoring system was validated in another cohort from 2019 to 2020.

RESULTS

Five hundred and thirteen eligible patients were divided into the experimental (405 patients; OAM, 22%) and validation cohorts (108 patients). Multivariate analysis identified tumor location of body/tail (odds ratio [OR] 4.45, P < .0001) and "high-risk markers" (OR 2.07, P = .011) as independent predictors of OAM. A scoring system consisting of body/tail (yes: 1, no: 0) and "high-risk markers" (yes: 1, no: 0) was constructed. In the validation cohort, when staging laparoscopy (SL) was performed for patients with scores 1/2, the eligibility for SL, sensitivity, and negative predictive value of OAM were 55%, 91%, and 96%, respectively.

CONCLUSIONS

Tumor location of body/tail and "high-risk markers" were independent predictors of OAM, composing our simple and reproducible risk scoring system.

Targeting Fibrosis: The Bridge That Connects Pancreatitis and Pancreatic Cancer

Pancreatic fibrosis is caused by the excessive deposits of extracellular matrix (ECM) and collagen fibers during repeated necrosis to repair damaged pancreatic tissue. Pancreatic fibrosis is frequently present in chronic pancreatitis (CP) and pancreatic cancer (PC). Clinically, pancreatic fibrosis is a pathological feature of pancreatitis and pancreatic cancer. However, many new studies have found that pancreatic fibrosis is involved in the transformation from pancreatitis to pancreatic cancer. Thus, the role of fibrosis in the crosstalk between pancreatitis and pancreatic cancer is critical and still elusive; therefore, it deserves more attention. Here, we review the development of pancreatic fibrosis in inflammation and cancer, and we discuss the therapeutic strategies for alleviating pancreatic fibrosis. We further propose that cellular stress response might be a key driver that links fibrosis to cancer initiation and progression. Therefore, targeting stress proteins, such as nuclear protein 1 (NUPR1), could be an interesting strategy for pancreatic fibrosis and PC treatment.

Relationship between the tumor location and clinicopathological features in left-sided pancreatic ductal adenocarcinoma

PURPOSE

Although the same distal pancreatectomy (DP) is performed regardless of the location of left-sided pancreatic ductal adenocarcinoma (PDAC), the clinicopathological features may differ depending on the tumor location. The present study investigated the relationship between the tumor location and clinicopathological features in patients with left-sided PDAC.

METHODS

The records of 59 patients who underwent DP for PDAC were enrolled. The relationship between the tumor location and clinicopathological features was investigated. The tumor location was classified into three groups according to the 7th AJCC/UICC TNM classification: body (Pb), body and tail (Pbt), and tail (Pt).

RESULTS

Tumors were located at the Pb in 26 patients, Pbt in 15, and Pt in 18. There was no metastasis to the lymph nodes around the common hepatic artery in Pt. The rate of peritoneal dissemination in the Pt was higher than that in the Pb (P = 0.034) or Pbt (P = 0.002). There were no significant differences in the overall survival among the three groups.

CONCLUSION

There was no metastasis to the lymph nodes around the common hepatic artery, and peritoneal dissemination was the most common site of recurrence in Pt tumors.