Fibroblast activation protein-targeted near-infrared photoimmunotherapy depletes immunosuppressive cancer-associated fibroblasts and remodels local tumor immunity.

BACKGROUND: Cancer-associated fibroblasts (CAFs) in the tumor microenvironment (TME) play a critical role in tumor immunosuppression. However, targeted depletion of CAFs is difficult due to their diverse cells of origin and the resulting lack of specific surface markers. Near-infrared photoimmunotherapy (NIR-PIT) is a novel cancer treatment that leads to rapid cell membrane damage. METHODS: In this study, we used anti-mouse fibroblast activation protein (FAP) antibody to target FAP+ CAFs (FAP-targeted NIR-PIT) and investigated whether this therapy could suppress tumor progression and improve tumor immunity. RESULTS: FAP-targeted NIR-PIT induced specific cell death in CAFs without damaging adjacent normal cells. Furthermore, FAP-targeted NIR-PIT treated mice showed significant tumor regression in the CAF-rich tumor model accompanied by an increase in CD8+ tumor infiltrating lymphocytes (TILs). Moreover, treated tumors showed increased levels of IFN-γ, TNF-α, and IL-2 in CD8+ TILs compared with non-treated tumors, suggesting enhanced antitumor immunity. CONCLUSIONS: Cancers with FAP-positive CAFs in their TME grow rapidly and FAP-targeted NIR-PIT not only suppresses their growth but improves tumor immunosuppression. Thus, FAP-targeted NIR-PIT is a potential therapeutic strategy for selectively targeting the TME of CAF+ tumors.

Overcoming cancer-associated fibroblast-induced immunosuppression by anti-interleukin-6 receptor antibody.

Cancer-associated fibroblasts (CAFs) are a critical component of the tumor microenvironment and play a central role in tumor progression. Previously, we reported that CAFs might induce tumor immunosuppression via interleukin-6 (IL-6) and promote tumor progression by blocking local IL-6 in the tumor microenvironment with neutralizing antibody. Here, we explore whether an anti-IL-6 receptor antibody could be used as systemic therapy to treat cancer, and further investigate the mechanisms by which IL-6 induces tumor immunosuppression. In clinical samples, IL-6 expression was significantly correlated with α-smooth muscle actin expression, and high IL-6 cases showed tumor immunosuppression. Multivariate analysis showed that IL-6 expression was an independent prognostic factor. In vitro, IL-6 contributed to cell proliferation and differentiation into CAFs. Moreover, IL-6 increased hypoxia-inducible factor 1α (HIF1α) expression and induced tumor immunosuppression by enhancing glucose uptake by cancer cells and competing for glucose with immune cells. MR16-1, a rodent analog of anti-IL-6 receptor antibody, overcame CAF-induced immunosuppression and suppressed tumor progression in immunocompetent murine cancer models by regulating HIF1α activation in vivo. The anti-IL-6 receptor antibody could be systemically employed to overcome tumor immunosuppression and improve patient survival with various cancers. Furthermore, the tumor immunosuppression was suggested to be induced by IL-6 via HIF1α activation.

PD-L1-expressing cancer-associated fibroblasts induce tumor immunosuppression and contribute to poor clinical outcome in esophageal cancer.

The programmed cell death 1 protein (PD-1)/programmed cell death ligand 1 (PD-L1) axis plays a crucial role in tumor immunosuppression, while the cancer-associated fibroblasts (CAFs) have various tumor-promoting functions. To determine the advantage of immunotherapy, the relationship between the cancer cells and the CAFs was evaluated in terms of the PD-1/PD-L1 axis. Overall, 140 cases of esophageal cancer underwent an immunohistochemical analysis of the PD-L1 expression and its association with the expression of the α smooth muscle actin, fibroblast activation protein, CD8, and forkhead box P3 (FoxP3) positive cells. The relationship between the cancer cells and the CAFs was evaluated in vitro, and the effect of the anti-PD-L1 antibody was evaluated using a syngeneic mouse model. A survival analysis showed that the PD-L1+ CAF group had worse survival than the PD-L1- group. In vitro and in vivo, direct interaction between the cancer cells and the CAFs showed a mutually upregulated PD-L1 expression. In vivo, the anti-PD-L1 antibody increased the number of dead CAFs and cancer cells, resulting in increased CD8+ T cells and decreased FoxP3+ regulatory T cells. We demonstrated that the PD-L1-expressing CAFs lead to poor outcomes in patients with esophageal cancer. The cancer cells and the CAFs mutually enhanced the PD-L1 expression and induced tumor immunosuppression. Therefore, the PD-L1-expressing CAFs may be good targets for cancer therapy, inhibiting tumor progression and improving host tumor immunity.

Neoadjuvant chemotherapy for locally advanced esophageal cancer comparing cisplatin and 5-fluorouracil versus docetaxel plus cisplatin and 5-fluorouracil: a propensity score matching analysis.

BACKGROUND: The standard treatment for locally advanced esophageal cancer is preoperative chemotherapy with cisplatin and 5-fluorouracil (CF), followed by surgery. Although docetaxel plus cisplatin and 5-fluorouracil (DCF) has been reported to have favorable outcomes, no study has compared its therapeutic efficacy to that of standard treatment. This study aimed to compare the therapeutic effects of CF and DCF in the real world by matching patient background factors using propensity scores. METHODS: We retrospectively reviewed the data of 237 patients with esophageal squamous cell carcinoma who underwent esophagectomy between January 2008 and December 2018. Patients were divided into two groups based on the preoperative chemotherapy regimens of CF (79 patients) or DCF (158 patients), and 49 matched pairs were finally analyzed using propensity score matching. Short- and long-term outcomes were compared between groups. RESULTS: After matching, although no significant differences in survival were observed among the groups, patients receiving DCF showed a significantly high histological response (P < 0.001). Subgroup analyses demonstrated that DCF therapy had better overall survival (P = 0.046) and relapse-free survival (P = 0.010) among pathological T3 and T4 cases. Whereas, adverse effects of chemotherapy were more frequent in the DCF group. CONCLUSIONS: Patients receiving DCF had higher pathological response and better survival than those receiving CF, especially in pathological T3 and T4 cases matched using propensity scores. Thus, the DCF regimen might be an effective treatment for locally advanced esophageal cancer. However, the adverse side effects of chemotherapy remain high and should be handled appropriately.

Initial introduction of robot-assisted, minimally invasive esophagectomy using the microanatomy-based concept in the upper mediastinum.

BACKGROUND: We have recently standardized upper mediastinal lymph node dissection (UMLND) using a microanatomy-based concept in thoracoscopic esophagectomy in the prone position (TEPP), and introduced robot-assisted minimally invasive esophagectomy (RAMIE) using the same concept as in TEPP while aiming at solo surgery. The purpose of this study was to investigate the outcomes of RAMIE using the microanatomy-based concept in the initial introduction phase. METHODS: We have performed more than 500 TEPP procedures as minimally invasive esophagectomy (MIE). After performing about 400 cases of MIE, we established a microanatomy-based standardization of UMLND. In October 2018, we introduced RAMIE, and have performed 75 procedures in 20 months. Two groups were analyzed: a group after microanatomy-based standardization in TEPP (100 cases after completing 400 cases of TEPP) and a RAMIE group (75 cases). Finally, 51 paired cases were matched using a propensity score. Furthermore, the change in postoperative short-term outcome for RAMIE in the initial introduction phase was analyzed. RESULTS: Although there were no significant differences between the two groups in the number of upper mediastinal lymph nodes dissected, there was a significant decrease (P = 0.036) in intraoperative blood loss volume with RAMIE, representing a definite benefit for patients. The thoracoscopic operative time for RAMIE decreased by almost 100 min following less than 50 cases of experience, reaching the same level as that for recent TEPP, but with only one-tenth the operator experience. There were no significant differences in the total postoperative morbidity rate including the recurrent laryngeal nerve palsy rate. CONCLUSION: RAMIE has been introduced safely and smoothly using the microanatomy-based concept established in TEPP.

Metachronous colorectal carcinoma with massive submucosal invasion detected by annual surveillance in a Lynch syndrome patient: a case report.

BACKGROUND: Lynch syndrome is the most common form of hereditary colorectal carcinoma. It is characterized by the presence of germline mutations in DNA mismatch repair genes. Mutation carriers have a lifetime risk of developing colorectal carcinoma of approximately 80%. Current treatment guidelines recommend periodic surveillance for colorectal carcinoma in patients with Lynch syndrome. However, the optimal interval between colonoscopies has not yet been determined. CASE PRESENTATION: We describe a 54-year-old man with Lynch syndrome who was undergoing annual colonoscopy surveillance for the development of colorectal carcinoma. At 54, 57, 59, and 60 years old, a colonoscopy showed high-grade dysplasia and adenoma. Therefore, endoscopic mucosal resection was performed. At 61 years old, a colonoscopy showed metachronous colorectal carcinoma with massive submucosal invasion. He subsequently underwent laparotomy for colorectal carcinoma. CONCLUSIONS: Annual surveillance using colonoscopy can detect colorectal carcinoma at an early stage, leading to reduced mortality. However, some patients might require a laparotomy, as was the case here. More frequent colonoscopic surveillance might be necessary to avoid surgery for colorectal carcinoma in Lynch syndrome patients with multiple risk factors for interval cancer.

Preoperative Risk Factors for Conversion of Laparoscopic Cholecystectomy to Open Cholecystectomy and the Usefulness of the 2013 Tokyo Guidelines.

To identify predictive factors for conversion from laparoscopic cholecystectomy (LC) to open cholecystectomy performed for mixed indications as an acute or elective procedure. We retrospectively analyzed the data of 236 consecutive cases of LC performed in our department between January 2012 and January 2015, and evaluated preoperative risk factors for conversion and the usefulness of the 2013 Tokyo guidelines (TG2013) for diagnosing acute cholecystitis. The conversion rate in our series was 8% (19/236 cases). The following independent predictive factors of conversion were identified (p≤0.04): previous upper abdominal surgery (odds ratio (OR), 14.6), pericholecystic fluid (OR, 10.04), acute cholecystitis (OR, 7.81), and emergent LC (OR, 15.8). Specifically for patients with acute cholecystitis defined using the 2013 Tokyo guidelines, use of an antiplatelet or anticoagulant drug for cardiovascular disease (p=0.043), previous upper abdominal surgery (p<0.031) and a resident as operator (p=0.041) were predictive factors. The risk factors for conversion identified herein could help to predict the difficulty of the procedure and could be used by surgeons to better inform patients regarding the risks for conversion. The TG2013 can be an effective tool for diagnosing acute cholecystitis to make informed clinical decisions regarding the optimal procedure for a patient.

[Tumor-infiltrating lymphocytes can be used to screen for lynch syndrome - a case report].

Lynch syndrome is an inherited syndrome associated with the development of colorectal and various other cancers. A 65- year-old male underwent a laparoscopic-assisted right hemi-colectomy for ascending colon cancer (cStage II). Histologically, his tumor was diagnosed as a poorly differentiated adenocarcinoma. Lymphocytic reactions, such as tumor-infiltrating lymphocytes (TIL), and Crohn's-like reactions, were observed. Genetic testing revealed the presence of a pathogenic mutation in the MLH1. In the Lynch syndrome, the most frequently observed findings include the accumulation of mutations, and an early onset of familial colon cancer. Although the case presented here did not show the typical clinical findings of Lynch syndrome, histological examination of the lymphocytic reactions proved useful for screening for Lynch syndrome. Herein, we establish the important role of the pathologist in alerting the clinician to the possibility of Lynch syndrome when the findings of TIL and Crohn's-like reactions are detected.

[A case of gastric cancer developed after pylorus-preserving gastrectomy in a patient with lynch syndrome].

Lynch syndrome is an inherited autosomal dominant disorder caused by germ-line mutation of mismatch repair genes, in which a malignant tumor develops at a young age in the colon, endometrium, stomach, or other tissues. A 54-year-old patient with gastric cancer received pylorus-preserving gastrectomy, and a genetic examination confirmed a pathological variation of the MLH1 gene. Five years after surgery, an upper gastrointestinal endoscopy revealed a residual 0 -IIa+IIc gastric tumor approximately 2 cm in size extending from the anastomotic site to the lesser curvature side of the stomach. The remaining stomach was completely removed. The final diagnosis was T1b (SM) N1M0, StageIB gastric cancer. Microsatellite instability was positive, and we attributed the cancer to Lynch syndrome. In Lynch syndrome, the risk of multicentric gastric cancer is higher than normal, and for the initial therapy, preventive total gastrectomy should be considered as an option.

Near-infrared Photoimmunotherapy Targeting Cancer-Associated Fibroblasts in Patient-Derived Xenografts Using a Humanized Anti-Fibroblast Activation Protein Antibody.

Esophageal cancer remains a highly aggressive malignancy with a poor prognosis, despite ongoing advancements in treatments such as immunotherapy. The tumor microenvironment, particularly cancer-associated fibroblasts (CAF), plays a crucial role in driving the aggressiveness of esophageal cancer. In a previous study utilizing human-derived xenograft models, we successfully developed a novel cancer treatment that targeted CAFs with near-infrared photoimmunotherapy (NIR-PIT), as an adjuvant therapy. In this study, we sought to translate our findings toward clinical practice by employing patient-derived xenograft (PDX) models and utilizing humanized mAbs, specifically sibrotuzumab, which is an antihuman fibroblast activation protein (FAP) Ab and already being investigated in clinical trials as monotherapy. PDX models derived from patients with esophageal cancer were effectively established, preserving the expression of key biomarkers such as EGFR and FAP, as observed in primary tumors. The application of FAP-targeted NIR-PIT using sibrotuzumab, conjugated with the photosensitizer IR700DX, exhibited precise binding and selective elimination of FAP-expressing fibroblasts in vitro. Notably, in our in vivo investigations using both cell line-derived xenograft and PDX models, FAP-targeted NIR-PIT led to significant inhibition of tumor progression compared with control groups, all without inducing adverse events such as weight loss. Immunohistologic assessments revealed a substantial reduction in CAFs exclusively within the tumor microenvironment of both models, further supporting the efficacy of our approach. Thus, our study demonstrates the potential of CAF-targeted NIR-PIT employing sibrotuzumab as a promising therapeutic avenue for the clinical treatment of patients with esophageal cancer.

Characteristic Distribution Pattern of CD30-positive Cytotoxic T Cells Aids Diagnosis of Kikuchi-Fujimoto Disease.

INTRODUCTION: Histiocytic necrotizing lymphadenitis (or Kikuchi-Fujimoto disease) frequently occurs in Asian young adult females and typically presents as cervical lymphadenopathy with unknown etiology. Although large immunoblasts frequently appear in Kikuchi-Fujimoto disease, the diffuse infiltration of these cells can cause difficulty in establishing a differential diagnosis from lymphoma. In such cases, CD30 immunostaining may be used; however, the extent or distribution pattern of CD30-positive cells in Kikuchi-Fujimoto disease remains largely unknown. Here we investigated the expression of CD30 and its clinicopathologic significance. MATERIALS AND METHODS: We investigated 30 Kikuchi-Fujimoto disease and 16 control [6, systemic lupus erythematosus (SLE); 10, reactive lymphoid hyperplasia (RLH)] cases. RESULTS: The number of CD30-positive cells in Kikuchi-Fujimoto disease was significantly more than that in SLE and RLH, and majority of these cells were located around necrotic areas. Moreover, double immunohistochemical staining showed these CD30-positive cells to be CD8-positive cytotoxic T cells, suggesting that activated cytotoxic T cells around necrotic areas are a characteristic feature of this disease. Clinicopathologic analysis showed that cases with abundant CD30-positive cells were predominantly female with only mild symptoms and normal laboratory data. CONCLUSIONS: In Kikuchi-Fujimoto disease cases, CD30-positive cytotoxic T cells were abundant around necrotic areas; this histologic feature may be helpful to differentiate this disease from SLE and RLH.

Evaluation of surgical treatment for incidental gallbladder carcinoma diagnosed during or after laparoscopic cholecystectomy: single center results.

BACKGROUND: Laparoscopic cholecystectomy (LC) is the accepted standard management for benign gallbladder disease. LC rarely results in a diagnosis of incidental gallbladder carcinoma (IGBC). The aim of our study was to report our experience with IGBC diagnosed during or following LC. METHODS: Between January 2008 and January 2015, 352 patients underwent LC at Iwakuni Clinical Center. Among these patients, 8 (2.3%) were diagnosed with IGBC. We evaluated their characteristics, surgical related variables, histopathological findings and surgical outcomes. RESULTS: Patient median age was 71 (range 49-88) years, and 3 out of 8 were female. All patients with IGBC were Japanese. The grade of cancer was as follows: pT1a (3 cases), pT2 (4 cases) and pT3 (1 case). Two patients with pT2 disease underwent radical surgery. The median follow-up time of these patients was 24 (range 11-80) months. All patients are still alive and two of three patients who refused radical surgery have developed recurrence (liver metastases and recurrence in the peritoneum). CONCLUSIONS: Although the number of cases was small, the results of this study further support the suggestion that gallbladder carcinoma may be curable if diagnosed as IGBC at an early stage. If the cancer has reached an advanced stage, radical surgery should be performed.

Synchronous coexistence of liver metastases from cecal leiomyosarcoma and rectal adenocarcinoma: A case report.

Multiple liver tumors represent a challenging condition for abdominal surgeons both in the selection of technique and the rarity of diagnosis. There are no case reports on co-existence of liver metastases from both intestinal leiomyosarcoma and adenocarcinoma. The patient described in this report successfully underwent resection of both primary lesions and liver metastases in combination with chemotherapy. As for the leiomyosarcoma, the primary cecal lesion was revealed more than three years after the patient's first visit. Peritoneal, lymph-node, and lung recurrences were observed afterward, and thus surgeries on those regions were performed. Pathologically, the peritoneal and lung recurrences comprised leiomyosarcoma and the lymph-node recurrence was diagnosed as adenocarcinoma. Despite newly discovered multiple lung recurrences and regional lymph-node metastases, the patient lived a normal life for 73 mo after the initial operation based on multidisciplinary therapy. He ultimately died of liver failure due to invasive lymph-node recurrence from the rectal adenocarcinoma, in addition to multiple lung recurrences from the leiomyosarcoma. Hepatic recurrence did not occur in this patient's case, which appears to be one reason for his long-term survival.

Changes over time in milk test results following pancreatectomy.

AIM: To investigate changes over time in, and effects of sealing technology on, milk test results following pancreatectomy. METHODS: From April 2008 to October 2013, 66 pancreatic resections were performed at the Iwakuni Clinical Center. The milk test has been routinely conducted at the institute whenever possible during pancreatectomy. The milk test comprises the following procedure: A nasogastric tube is inserted until the third portion of the duodenum, followed by injection of 100 mL of milk through the tube. If a chyle leak is present, the patient tests positive in this milk test based on the observation of a white milky discharge. Positive milk test rates, leakage sites, and chylous ascites incidence were examined. LigaSure™ (LS; Covidien, Dublin, Ireland), a vessel-sealing device, is routinely used in pancreatectomy. Positive milk test rates before and after use of LS, as well as drain discharge volume at the 2(nd) and 3(rd) postoperative days, were compared retrospectively. Finally, positive milk test rates and chylous ascites incidence were compared with the results of a previous report. RESULTS: Fifty-nine milk tests were conducted during pancreatectomy. The positive milk test rate for all pancreatectomy cases was 13.6% (8 of 59 cases). One case developed postoperative chylous ascites (2.1% among the pancreatoduedenectomy cases and 1.7% among all pancreatectomies). Positive rates by procedure were 12.8% for pancreatoduodenectomy and 22.2% for distal pancreatectomy. Positive rates by disease were 17.9% for pancreatic and 5.9% for biliary diseases. When comparing results from before and after use of LS, positive milk test rates in pancreatoduodenectomy were 13.0% before and 12.5% after, while those in distal pancreatectomy were 33.3% and 0%. Drainage volume tended to decrease when LS was used on the 3(rd) postoperative day (volumes were 424 ± 303 mL before LS and 285 ± 185 mL after, P = 0.056). Both chylous ascites incidence and positive milk test rates decreased slightly compared with those rates from the previous study. CONCLUSION: Positive milk test rates and chylous ascites incidence decreased over time. Sealing technology may thus play an important role in preventing postoperative chylous ascites.

Surgical resection of splenic metastasis from the adenosquamous gallbladder carcinoma: A case report.

INTRODUCTION: Splenic metastasis of gallbladder carcinoma is extremely rare. Specific anatomical, histological, and functional properties of spleen are believed to be responsible for the rarity of solitary splenic metastasis. PRESENTATION OF CASE: We present the case of a 62-year-old female who developed metachronous splenic metastasis of adenosquamous carcinoma of the gallbladder. We performed central bisegmentectomy of the liver for gallbladder carcinoma. The patient subsequently presented 3 months later with isolated splenic metastasis and liver metastasis. Splenectomy and partial hepatectomy was performed at this time. Histological examination confirmed metastatic adenosquamous carcinoma of the gallbladder. No signs of recurrence were observed at 3 months after the second surgery. DISCUSSION: Although splenectomy provides a potential means of radical treatment in patients with isolated splenic metastases, it should be performed with caution as splenic metastatic lesions may represent the initial clinical manifestation of systemic metastases at multiple sites. In this case, radical surgery was performed following the confirmation of no new unresectable metastatic lesions or systemic dissemination. CONCLUSION: This is the first report on the adenosquamous splenic metastasis from the gallbladder carcinoma. Curative resection may be the treatment of choice for prolonging survival in patients with the splenic metastasis of gallbladder carcinoma.