It is extensively documented that tumor hypoxia contributes to the failure of chemotherapy and radiotherapy. Recent evidence suggests that hypoxia is also closely involved in the resistance to immunotherapy. In this review, we highlight how immune cells that are essential for the maximized immunotherapy efficacy, including cytotoxic T cells, dendritic cells, and natural killer cells, can adapt to tumor hypoxia. We then outline previous attempts targeting tumor hypoxia (for example, modulators of tumor cell oxygen consumption, perfusion modulators, hypoxia-activated prodrugs, hypoxia-inducible factor inhibitors, and hypoxia-responsive chimeric antigen receptor T cells) discussing how these approaches have resulted in an improvement of the antitumor response to immunotherapy in preclinical or clinical settings. Lastly, we review various non-invasive techniques to detect the tumor hypoxia and immune responses. We believe that an integration of the biological knowledge of immune cell adaptation to tumor hypoxia with the cutting edge non-invasive imaging technologies may ultimately allow us not only to select for patients who would benefit the most from the immunotherapy but also to monitor their responses in a real-time manner so that we can offer them an optimal personalized medicine in the clinic.

Purpose: The benefit of adjuvant chemotherapy following curative-intent surgery in pancreatic ductal adenocarcinoma (PDAC) patients who had received neoadjuvant FOLFIRINOX is unclear. This study aimed to assess the survival benefit of adjuvant chemotherapy in this patient population. Materials and Methods: This retrospective study included 218 patients with localized non-metastatic PDAC who received neoadjuvant FOLFIRINOX and underwent curative-intent surgery (R0 or R1) between January 2017 and December 2020. The association of adjuvant chemotherapy with disease-free survival (DFS) and overall survival (OS) was evaluated in overall patients and in the propensity score matched (PSM) cohort. Subgroup analysis was conducted according to the pathology-proven lymph node status. Results: Adjuvant chemotherapy was administered to 149 patients (68.3%). In the overall cohort, the adjuvant chemotherapy group had significantly improved DFS and OS compared to the observation group (DFS: median, 13.8 months [95% confidence interval (CI), 11.0 to 19.1] vs. 8.2 months [95% CI, 6.5 to 12.0]; p < 0.001; and OS: median, 38.0 months [95% CI, 32.2 to not assessable] vs. 25.7 months [95% CI, 18.3 to not assessable]; p=0.005). In the PSM cohort of 57 matched pairs of patients, DFS and OS were better in the adjuvant chemotherapy group than in the observation group (p < 0.001 and p=0.038, respectively). In the multivariate analysis, adjuvant chemotherapy was a significant favorable prognostic factor (vs. observation; DFS: hazard ratio [HR], 0.51 [95% CI, 0.36 to 0.71; p < 0.001]; OS: HR, 0.45 [95% CI, 0.29 to 0.71; p < 0.001]). Conclusion Among PDAC patients who underwent surgery following neoadjuvant FOLFIRINOX, adjuvant chemotherapy may be associated with improved survival. Randomized studies should be conducted to validate this finding.

Purpose: Multidisciplinary care has become a cornerstone of colorectal cancer management. To evaluate the clinical efficacy of a geriatric multidisciplinary oncology clinic (GMOC), we analyzed the surgical treatment decision-making process and outcomes. Methods: This retrospective single-center study reviewed the data of patients aged ≥65 years who participated in the GMOC at a tertiary referral hospital between 2015 and 2021. The clinical adherence rate, comprehensive geriatric assessment, and a multidimensional frailty score (MFS) were obtained. The groups that were recommended and not recommended for surgery were compared, analyzing the factors impacting the decision and 1-year survival outcomes. Furthermore, the postoperative complications of patients who underwent surgery were evaluated. Results: A total of 165 patients visited the GMOC, and 74 had colorectal cancer (mean age, 85.5 years [range, 81.2–89.0 years]). Among patients with systemic disease (n = 31), 7 were recommended for surgery, and 5 underwent surgery. Among patients with locoregional disease (n = 43), 18 were recommended for surgery, and 12 underwent surgery. Patients recommended and not recommended for surgery had significantly different activities of daily living (ADL) (P = 0.024), instrumental ADL (P = 0.001), Mini-Mental State Examination (P = 0.014), delirium risk (P = 0.039), and MFS (P = 0.001). There was no difference in the 1-year overall survival between the 2 groups (P = 0.980). Of the 17 patients who underwent surgery, the median (interquartile range) of operation time was 165.0 minutes (120.0–270.0 minutes); hospital stay, 7.0 days (6.0–8.0 days); and 3 patients had wound complications. Conclusion Proper counseling of patients through the GMOC could lead to appropriate management and favorable outcomes.

Neuroendocrine tumors (NETs) are a group of malignancies arising from neuroendocrine cells and frequently originate in the gastrointestinal tract and pancreas. Although curative resection is the main treatment for localized disease, systemic therapy is needed for relapsed or metastatic/unresectable gastroenteropancreatic NETs (GEP-NETs). Although there are several NET treatment guidelines from various countries, the geographical discrepancies between patient clinical characteristics, the regulatory approval status for therapeutic agents, and medical practices necessitate specific guidelines for Korean patients. We here provide a consensus review of the diagnosis, staging and systemic treatment of Korean GEP-NET patients. Systemic therapy options and the current Korean expert consensus on these treatments, including somatostatin analogs, targeted therapies such as everolimus and sunitinib, peptide receptor radionuclide treatments, and cytotoxic chemotherapies are addressed.

Purpose: This study evaluated the efficacy of adjuvant chemotherapy (AC) in patients with resected ampulla of Vater (AoV) carcinoma. Materials and Methods: Data from 646 patients who underwent surgical resection at Asan Medical Center between 2000 and 2017 were retrospectively reviewed. Results: The median age of the patients was 62 years, and 54.2% were male. Patients were classified into AC group (n=165, 25.5%) and no AC group (n=481, 74.5%). With a median follow-up duration of 88 months, in patients with stage I, II, III, median recurrence-free survival (RFS) was not reached, 44 months, and 15 months, respectively, and the median overall survival (OS) were not reached, 88 months and 35 months, respectively. Despite no statistical significance, RFS and OS were better in stage II patients with AC than in those without AC (median RFS, 151 months vs. 38 months; p=0.156 and median OS, 153 months vs. 74 months; p=0.299). In multivariate analysis for RFS and OS, TNM stage, R1 resection status, presence of lymphovascular invasion, and perineural invasion remained significant factors, whereas AC (hazard ratio [HR], 0.74; 95% confidence interval [CI], 0.54 to 1.00; p=0.052) was marginally related with RFS. After propensity score matching in only stage II/III patients, RFS and OS with AC were numerically longer than those without AC (HR, 0.80; 95% CI, 0.60 to 1.06; p=0.116 and HR, 0.77; 95% CI, 0.56 to 1.06; p=0.111). Conclusion AC with fluoropyrimidine did not improve survival of patients with resected AoV carcinoma. However, multivariate analysis with prognostic factors showed a marginally significant survival benefit with AC.

Neuroendocrine tumors (NETs) are a group of malignancies arising from neuroendocrine cells and frequently originate in the gastrointestinal tract and pancreas. Although curative resection is the main treatment for localized disease, systemic therapy is needed for relapsed or metastatic/unresectable gastroenteropancreatic NETs (GEP-NETs). Although there are several NET treatment guidelines from various countries, the geographical discrepancies between patient clinical characteristics, the regulatory approval status for therapeutic agents, and medical practices necessitate specific guidelines for Korean patients. We here provide a consensus review of the diagnosis, staging and systemic treatment of Korean GEP-NET patients. Systemic therapy options and the current Korean expert consensus on these treatments, including somatostatin analogs, targeted therapies such as everolimus and sunitinib, peptide receptor radionuclide treatments, and cytotoxic chemotherapies are addressed.

Purpose: This study evaluated the efficacy of adjuvant chemotherapy (AC) in patients with resected ampulla of Vater (AoV) carcinoma. Materials and Methods: Data from 646 patients who underwent surgical resection at Asan Medical Center between 2000 and 2017 were retrospectively reviewed. Results: The median age of the patients was 62 years, and 54.2% were male. Patients were classified into AC group (n=165, 25.5%) and no AC group (n=481, 74.5%). With a median follow-up duration of 88 months, in patients with stage I, II, III, median recurrence-free survival (RFS) was not reached, 44 months, and 15 months, respectively, and the median overall survival (OS) were not reached, 88 months and 35 months, respectively. Despite no statistical significance, RFS and OS were better in stage II patients with AC than in those without AC (median RFS, 151 months vs. 38 months; p=0.156 and median OS, 153 months vs. 74 months; p=0.299). In multivariate analysis for RFS and OS, TNM stage, R1 resection status, presence of lymphovascular invasion, and perineural invasion remained significant factors, whereas AC (hazard ratio [HR], 0.74; 95% confidence interval [CI], 0.54 to 1.00; p=0.052) was marginally related with RFS. After propensity score matching in only stage II/III patients, RFS and OS with AC were numerically longer than those without AC (HR, 0.80; 95% CI, 0.60 to 1.06; p=0.116 and HR, 0.77; 95% CI, 0.56 to 1.06; p=0.111). Conclusion AC with fluoropyrimidine did not improve survival of patients with resected AoV carcinoma. However, multivariate analysis with prognostic factors showed a marginally significant survival benefit with AC.

Voiding cystourethrography (VCUG) demonstrates the anatomy of the urinary system and is used to detect the presence/absence of vesicoureteral reflux. It is the most important modality for urological fluoroscopic examination in children. For improved patient care, it is important to understand and perform VCUG appropriately. Therefore, an in-depth review of VCUG protocols and techniques has been presented herein. In addition, tips, tricks, and pitfalls associated with the technique have also been addressed.

Purpose: The current standard chemotherapy for advanced biliary tract cancer (BTC) has limited benefit,and novel therapies need to be investigated. Materials and Methods: In this prospective cohort study, programmed death ligand-1 (PD-L1)–positive BTC patientswho progressed on first-line gemcitabine plus cisplatin were enrolled. Pembrolizumab 200mg was administered intravenously every 3 weeks. Results: Between May 2018 and February 2019, 40 patients were enrolled. Pembrolizumab wasgiven as second-line (47.5%) or  third-line therapy (52.5%). The objective response ratewas 10% and 12.5% by Response Evaluation Criteria in Solid Tumor (RECIST) v1.1 andimmune-modified RECIST (imRECIST) and median duration of response was 6.3 months.Among patients with progressive disease as best response, one patient (1/20, 5.0%)achieved complete response subsequently. The median progression-free survival (PFS) andoverall survival (OS) were 1.5 months (95% confidence interval [CI], 0.0 to 3.0) and 4.3months (95% CI, 3.5 to 5.1), respectively, and objective response per imRECIST was significantlyassociated with PFS (p < 0.001) and OS (p=0.001). Tumor proportion score  50%was significantly associated with higher response rates including the response after pseudoprogression(vs. < 50%; 37.5% vs. 6.5%; p=0.049). Conclusion Pembrolizumab showed modest anti-tumor activity in heavily pretreated PD-L1–positiveBTC patients. In patients who showed objective response, durable response could beachieved.

Purpose: Since the introduction of nab-paclitaxel plus gemcitabine (nab-P+GEM) as first-line (1L) treatment for metastatic pancreatic adenocarcinoma (mPDAC), optimal second-line (2L) chemotherapy after progression is unclear. We assessed clinical outcomes of 2L chemotherapy for disease that progressed on 1L nab-P+GEM. Materials and Methods: Among the 203 patients previously treated with 1L nab-P+GEM for mPDAC at Asan Medical Center, between February and December 2016, records of 120 patients receiving 2L chemotherapy after progression on nab-P+GEM were retrospectively reviewed. The response rate and survival were evaluated along with analysis of prognostic factors. Results: Fluoropyrimidine-oxaliplatin doublets (FOLFOX or XELOX) were used in 78 patients (65.0%), fluoropyrimidine monotherapy in 37 (30.8%), and liposomal irinotecan plus fluorouracil in two (1.7%). The median progression-free survival (PFS) and overall survival (OS) were 3.29 months and 7.33 months from the start of 2L therapy. Fluoropyrimidine-oxaliplatin regimens and fluoropyrimidine monotherapy did not yield significantly different median PFS (2.89 months vs. 3.81 months, p=0.40) or OS (7.04 months vs. 7.43 months, p=0.86). A high neutrophil-lymphocyte ratio (> 2.2) and a short time to progression with 1L nab-P+GEM (< 6.4 months) were independent prognostic factors of poor OS with 2L therapy. Conclusion 2L fluoropyrimidine-oxaliplatin doublets and fluoropyrimidine monotherapy after failure of 1L nab-P+GEM had modest efficacy, with no differences in treatment outcomes between them. Further investigation is warranted for the optimal 2L chemo-regimens and sequencing of systemic chemotherapy for patients with mPDAC.