Colorectal cancer is the third most common malignancy worldwide, with 1.3 million new cases annually. Metastasis to the liver is a leading cause of mortality in these patients. In human liver, metastatic cancer cells must evade populations of liver-resident natural killer (NK) cells with potent cytotoxic capabilities. Here, we investigated how these tumors evade liver NK-cell surveillance. Tissue biopsies were obtained from patients undergoing resection of colorectal liver metastasis (CRLM, n ¼ 18), from the tumor, adjacent tissue, and distal resection margin. The number and phenotype of liver-resident NK cells, at each site, were analyzed by flow cytometry. Tumorconditioned media (TCM) was generated for cytokine and metabolite quantification and used to treat healthy liverresident NK cells, isolated from donor liver perfusate during transplantation. Liver-resident NK cells were significantly depleted from CRLM tumors. Healthy liver-resident NK cells exposed to TCM underwent apoptosis in vitro, associated with elevated lactate. Tumor-infiltrating liver-resident NK cells showed signs of mitochondrial stress, which was recapitulated in vitro by treating liver-resident NK cells with lactic acid. Lactic acid induced apoptosis by decreasing the intracellular pH of NK cells, resulting in mitochondrial dysfunction that could be prevented by blocking mitochondrial ROS accumulation. CRLM tumors produced lactate, thus decreasing the pH of the tumor microenvironment. Liver-resident NK cells migrating toward the tumor were unable to regulate intracellular pH resulting in mitochondrial stress and apoptosis. Targeting CRLM metabolism provides a promising therapeutic approach to restoring local NK-cell activity and preventing tumor growth.

Background The risk factors for surgical site infection (SSI) after HPB surgery are poorly defined. This meta‐analysis aimed to quantify the SSI rates and risk factors for SSI after pancreas and liver resection. Methods The PUBMED, MEDLINE and EMBASE databases were systematically searched using the PRISMA framework. The primary outcome measure was pooled SSI rates. The secondary outcome measure was risk factor profile determination for SSI. Results The overall rate of SSI after pancreatic and liver resection was 25.1 and 10.4%, respectively (p < 0.001). 32% of pancreaticoduodenectomies developed SSI vs 23% after distal pancreatectomy (p < 0.001). The rate of incisional SSI in the pancreatic group was 9% and organ/space SSI 16.5%. Biliary resection during liver surgery was a risk factor for SSI (25.0 vs 15.7%, p = 0.002). After liver resection, the incisional SSI rate was 7.6% and the organ space SSI rate was 10.2%. Pancreas‐specific SSI risk factors were pre‐operative biliary drainage (p < 0.001), chemotherapy (p < 0.001) and radiotherapy (p = 0.007). Liver‐specific SSI risk factors were smoking (p = 0.046), low albumin (p < 0.001) and significant blood loss (p < 0.001). The rate of organ/space SSI in patients with POPF was 47.7% and in patients without POPF 7.3% (p < 0.001). Organ/space SSI rate was 43% in patients with bile leak and 10% in those without (p < 0.001). Conclusions The risk factors for SSI following pancreatic and liver resections are distinct from each other, with higher SSI rates after pancreatic resection. Pancreaticoduodenectomy has increased risk of SSI compared to distal pancreatectomy. Similarly, biliary resections during liver surgery increase the rates of SSI.

Purpose Informal caregivers play an important supportive care role for patients with cancer. This may be especially true for pancreatic cancer which is often diagnosed late, has a poor prognosis and is associated with a significant symptom burden. We systematically reviewed the evidence on caregiver burden, unmet needs and quality-of-life of informal caregivers to patients with pancreatic cancer. Method PubMed, Medline, CINAHL and Embase databases were systematically searched on 31 August 2021. Qualitative and quantitative data on informal caregivers’ experiences were extracted and coded into themes of burden, unmet needs or quality-of-life with narrative synthesis of the data undertaken. Results Nine studies (five qualitative, four quantitative), including 6023 informal caregivers, were included in the review. We categorised data into three key themes: caregiver burden, unmet needs and quality-of-life. Data on caregiver burden was organised into a single subtheme relating to symptom management as a source of burden. Data on unmet needs was organised into three subthemes need for: better clinical communication; support and briefings for caregivers; and help with navigating the health care system. Data on quality-of-life indicate large proportions of informal caregivers experience clinical levels of anxiety (33%) or depression (12%-32%). All five qualitative studies were graded as good quality; three quantitative studies were poor quality, and one was fair quality. Conclusion High-quality pancreatic cancer care should consider the impacts of informal caregiving. Prospective longitudinal studies examining multiple dimensions of caregiver burden, needs, and quality-of-life would be valuable at informing supportive care cancer delivery to pancreatic cancer informal caregivers.