Hepatic arterial infusion chemotherapy with gemcitabine and 5-fluorouracil or oral S-1 improves the prognosis of patients with postoperative liver metastases from pancreatic cancer

Pancreatic Cancer: A Review of Current Treatment and Novel Therapies

Pancreatic cancer is one of the leading causes for cancer-related deaths in the United States. Majority of patients present with unresectable or metastatic disease. For those that present with localized disease, a multidisciplinary approach is necessary to maximize survival and optimize outcomes. The quality and safety of surgery for pancreatic cancer have improved in recent years with increasing adoption of minimally invasive techniques and surgical adjuncts. Systemic chemotherapy has also evolved to impact survival. It is now increasingly being utilized in the neoadjuvant setting, often with concomitant radiation. Increased utilization of genomic testing in metastatic pancreatic cancer has led to better understanding of their biology, thereby allowing clinicians to consider potential targeted therapies. Similarly, targeted agents such as PARP inhibitors and immune checkpoint- inhibitors have emerged with promising results. In summary, pancreatic cancer remains a disease with poor long-term survival. However, recent developments have led to improved outcomes and have changed practice in the past decade. This review summarizes current practices in pancreatic cancer treatment and the milestones that brought us to where we are today, along with emerging therapies.

Hepatic Arterial Infusion Chemotherapy for Liver Metastases Following Standard Chemotherapy for Pancreatic Cancer

A 65-year-old man diagnosed with locally advanced pancreatic cancer underwent distal pancreatectomy and combined portal vein resection. One month after surgery, contrast-enhanced magnetic resonance imaging revealed multiple liver metastases. We administered two courses of gemcitabine plus nab-paclitaxel combination therapy followed by 17 modified FOLFIRINOX courses. However, the response was insufficient, and the patient thereafter developed grade 3 neutropenia, which made it difficult to continue the treatment regimen. As a result, we administered hepatic arterial infusion chemotherapy comprising gemcitabine plus 5-fluorouracil because the residual tumor was limited to liver metastases. The progression-free survival period was 7 months, and no drug-related adverse effects were noted during the treatment.

Neoadjuvant chemotherapy with gemcitabine-based regimens improves the prognosis of node positive resectable pancreatic head cancer

The effectiveness of preoperative (neoadjuvant) chemotherapy (NAC) for resectable pancreatic ductal adenocarcinoma (PDAC) remains unclear. The present study retrospectively evaluated the efficacy of NAC with gemcitabine (GEM)-based regimens or GEM monotherapy for resectable PDAC. Between 2006 and 2015, NAC with GEM was performed in 52 cases (head 31, and body and tail 21) and compared with 34 resection-only cases serving as controls (head 20, and body and tail 14). According to the Response Evaluation Criteria In Solid Tumors guidelines, the treatment effect was a partial response in 5 cases, stable disease in 45 cases, and progressive disease in 2 cases. Maximum standardized uptake values and carbohydrate antigen (CA19-9) values were significantly reduced after preoperative chemotherapy. Using the Evans grading system, the treatment effect was grade I in 31 patients, grade IIa in 8, and grade IIb in 3 cases. There were significant differences in the overall survival rate between the NAC and control groups, only in the patients with node-positive pancreatic head cancer. Significantly higher CA19-9 values in peripheral blood and higher lymph node metastasis and plexus invasion rates were observed in early-recurring cases within a year. The preoperative CA 19-9 cutoff value as an early recurrence risk factor was calculated as 30 U/ml in the NAC group and 88 U/ml in the control group. NAC with GEM prolonged survival in patients with node-positive pancreatic head cancer. High CA19-9 values before operation, lymph node metastases and plexus invasion were risk factors for early tumor recurrence after surgery. Preoperative chemotherapy would be necessary for resectable pancreatic head cancer as lymph node metastasis was observed in >60% with resectable PDAC. Moreover, if normalization of CA19-9 values is not achieved with NAC, extension of preoperative chemotherapy should be considered as for borderline resectable PDAC cases.

Solid pseudopapillary neoplasm of the pancreas: Clinical-pathological features and management, a single-center experience

Solid pseudopapillary neoplasm of the pancreas is a rare tumor of low malignancy that occurs most often in females. The study describes the clinicopathologic characteristics of the tumor and common differential diagnoses. Data were collected from a prospectively maintained database. Of 1661 patients operated for pancreatic tumors between January 2001 and September 2018, 15 patients were recorded. Patients included 12 females and 3 males, median age 40 (range 10 -87) years. Computed tomography or magnetic resonance imaging was diagnostic in eight patients and a preoperative biopsy in eight out of 10 patients. Median tumor size was 5 cm (range 2 -16 cm), 12 tumors were in the head, six in the body, and three in the tail of the gland. All patients except one had radical resection including one with hepatic and lymph node metastases, no patient underwent oncologic treatment. All patients are alive from 17.5 to 209.4 months postoperatively and without recurrence. Radical operation is usually curative and should also be offered to patients with metastases or recurrence as oncologic treatment has limited effect.

Contribution of equilibrative nucleoside transporters 1 and 2 to gemcitabine uptake in pancreatic cancer cells

Hepatic arterial infusion (HAI) chemotherapy is expected to be a more effective and safer method to treat the hepatic metastasis of pancreatic cancer than intravenous (iv) administration because of higher tumor exposure and lower systemic exposure. To clarify the uptake mechanism of nucleoside anticancer drugs, including gemcitabine (GEM), in pancreatic cancer, we investigated the uptakes of radiolabeled uridine (a general substrate of nucleoside transporters) and GEM in pancreatic cancer cell lines MIA-PaCa2 and As-PC1. Uridine uptake was inhibited by non-labeled GEM and also by S-(4-nitrobenzyl)-6-thioinosine (NBMPR; an inhibitor of equilibrative nucleoside transporters, ENTs) in a concentration-dependent manner, suggesting that ENTs contribute to uridine uptake in pancreatic cancer cells. As for GEM, saturable uptake was mediated by high- and low-affinity components with K_m values of micromolar and millimolar orders, respectively. Uptake was inhibited in a concentration-dependent manner by NBMPR and was sodium ion-independent. Moreover, the concentration dependence of uptake in the presence of 0.1 μM NBMPR showed a single low-affinity site. These results indicated that the high- and low-affinity sites correspond to hENT1 and hENT2, respectively. The results indicated that at clinically relevant hepatic concentrations of GEM in GEM-HAI therapy, the metastatic tumor exposure of GEM is predominantly determined by hENT2 under unsaturated conditions, suggesting that hENT2 expression in metastatic tumor would be a candidate biomarker for indicating anticancer therapy with GEM-HAI.

Making the Case: Intra-arterial Therapy for Less Common Metastases

Intra-arterial therapies have high antitumor activity for both primary and secondary hepatic malignancies. Selective infusions allow increased delivery of cytoreductive therapy to the tumor bed while sparing the normal hepatic parenchyma. These therapies are now often applied in the outpatient setting or with short overnight hospital stays and have a growing role in the treatment of liver-dominant disease from metastatic colorectal cancer and from neuroendocrine tumors. Less commonly, intra-arterial therapies are applied to treat secondary hepatic malignancies from breast cancer, melanoma, pancreatic adenocarcinoma, and soft-tissue sarcomas. The available data are limited and generally retrospective observational cohort series of single institutions. The purpose of this article is to summarize the recent literature on outcomes for intra-arterial therapy in nonsurgical patients. Multi-institutional registries and prospective data are greatly needed, as intra-arterial therapies are increasingly applied in these patients to stop progression of chemorefractory tumors.

Saturable Hepatic Extraction of Gemcitabine Involves Biphasic Uptake Mediated by Nucleoside Transporters Equilibrative Nucleoside Transporter 1 and 2

Hepatic arterial infusion (HAI) chemotherapy with gemcitabine (GEM) is expected to be more effective and safer method to treat hepatic metastasis of pancreatic cancer compared with intravenous administration, because it affords higher tumor exposure with lower systemic exposure. Thus, a key issue for dose selection is the saturability of hepatic uptake of GEM. Therefore, we investigated GEM uptake in rat and human isolated hepatocytes. Hepatic GEM uptake involved high- and low-affinity saturable components with Km values of micromolar and millimolar order, respectively. The uptake was inhibited concentration dependently by S-(4-nitrobenzyl)-6-thioinosine (NBMPR) and was sodium-ion-independent, suggesting a contribution of equilibrative nucleoside transporters (ENTs). The concentration dependence of uptake in the presence of 0.1 μM NBMPR showed a single low-affinity binding site. Therefore, the high- and low-affinity sites correspond to ENT1 and ENT2, respectively. Our results indicate hepatic extraction of GEM is predominantly mediated by the low-affinity site (hENT2), and at clinically relevant hepatic concentrations of GEM, hENT2-mediated uptake would not be completely saturated. This is critical for HAI, because saturation of hepatic uptake would result in a marked increase of GEM concentration in the peripheral circulation, abrogating the advantage of HAI over intravenous administration in terms of severe adverse events.