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 (CAFs), 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 monoclonal antibodies, specifically Sibrotuzumab, which is anti-human fibroblast activation protein (FAP) antibody and already being investigated in clinical trials as monotherapy. PDX models derived from esophageal cancer patients 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 to control groups, all without inducing adverse events such as weight loss. Immunohistological 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 clinical treatment of esophageal cancer patients.

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.

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.

Solitary Cardiac Metastasis of Hepatocellular Carcinoma.

Cardiac metastasis originating from hepatocellular carcinoma (HCC) is a rare condition with a poor prognosis. No therapeutic standards for cardiac metastasis originating from HCC have been established. At 19 months after a curative hepatectomy, a 64-year-old Japanese hepatitis B virus-positive male patient experienced solitary cardiac metastasis originating from HCC. The cardiac tumor was discovered in the right ventricle. The patient received three courses of radiotherapy and chemotherapy and survived > 3 years after the initial diagnosis of cardiac metastasis. His case demonstrates that radiotherapy combined with chemotherapy can be an effective treatment for cardiac metastasis.

The Late Phase/Early Phase Ratio of Pancreatic CT Values as a Novel Predictor of Pancreatic Fistula after Distal Pancreatectomy.

Post-operative pancreatic fistula (POPF) remains the most common complication after distal pancreatectomy (DP). In this retrospective study, we reviewed the data from patients who underwent DP between 2008 and 2019 in our institute to determine whether the late phase/early phase ratio (L/E ratio) by preoperative computed tomography (CT) scan in the pancreas could predict POPF occurrence after DP. We examined the relationship between preoperative or intraoperative factors and the occurrence of POPF after DP using statistical methods in 23 males and 21 females with a mean age of 73. The mean L/E ratio was significantly lower in the POPF group than the non-POPF group (p=0.035). The L/E ratio had moderate diagnostic accuracy, with a calculated optimal cutoff value of 0.77. In univariate analysis, a significant association was noted between POPF and stump thickness ≥ 16.9, body mass index ≥ 27.5, and L/E ratio ≤ 0.77. In the multivariate analysis, the L/E ratio (odds ratio, 5.96; p=0.036) was an independent risk factor for POPF. Our findings suggest that the pancreatic L/E ratio may predict the occurrence of POPF after DP. This measure may be useful in preoperative risk stratification, patient counseling, and perioperative patient management, improving clinical outcomes after DP.

Preoperative predictive factors of pancreatic fistula after pancreaticoduodenectomy: usefulness of the CONUT score.

PURPOSE: Postoperative pancreatic fistula (POPF) is the most important factor affecting morbidity and mortality after pancreaticoduodenectomy (PD). Patients with a high controlling nutritional status (CONUT) score, which is used to assess nutritional status, are expected to have high morbidity rates. This study aimed to determine the usefulness of the CONUT score. METHODS: Data from 97 consecutive cases of PD performed in the Department of Surgery of Iwakuni Clinical Center, from April 2008 to May 2018, were included. Preoperative patient data, including sex, age, and hypertension, and postoperative complication data were collected to analyze pancreatic fistula occurrence. RESULTS: Of the 97 patients, 2 9 patients (29.8%) were diagnosed with POPF ≥ B, with 26 cases (26.8%) classified as grade B and 3 (3.1%) as grade C. The mortality rate was 2.1% (2 of 97). In the univariate analysis, a significant association was observed between POPF and the following factors: body mass index (BMI) ≥ 22 kg/m2, high CONUT score, nonpancreatic carcinoma, and CT attenuation values. In multivariate analysis, BMI ≥ 22 kg/m2 (odds ratio [OR], 6.16; P < 0.001), high CONUT score (OR, 3.77; P = 0.009), nonpancreatic carcinoma (OR, 5.72; P = 0.009), and CT attenuation values (late/early ratio) in the pancreas (OR, 9.07; P = 0.006) were independent risk factors for POPF. CONCLUSION: Patients with a high CONUT score are at high risk of POPF. Further study correlating preoperative nutritional intervention with risk of POPF is necessary.

Preoperative C-Reactive Protein/Albumin Ratio as a Predictive Factor for Gallbladder Carcinoma.

BACKGROUND/AIM: The C-reactive protein (CRP) to albumin ratio (CAR) is associated with outcomes in patients with sepsis. We aimed to evaluate the significance of preoperative CAR in therapeutic outcomes after gallbladder carcinoma (GBC) resection. PATIENTS AND METHODS: Fifty-three patients who underwent surgical resection for GBC between January 2008 and September 2019 were enrolled. We retrospectively investigated the relation between preoperative CAR and overall and disease-free survival. RESULTS: The optimal cut-off CAR was 0.07. Multivariate analysis showed that i) R1 or R2 resection (p=0.033), ii) advanced tumor stage (p=0.047), iii) CAR≥0.07 (p=0.011), and iv) postoperative complications (p=0.028) were significant independent predictors of overall survival; moreover, higher carbohydrate antigen levels (p=0.036) and R1 or R2 resection (p<0.001) were significant independent predictors of disease-free survival. CONCLUSION: Preoperative CAR may be a significant independent predictor of long-term outcomes after GBC resection.

Preoperative Nutritional Assessment Using the Controlling Nutritional Status Score to Predict Pancreatic Fistula After Pancreaticoduodenectomy.

Backgound: This study aimed to determine the usefulness of the Controlling Nutritional Status (CONUT) scorescore for predicting postoperative pancreatic fistula (POPF). PATIENTS AND METHODS: Data from 108 consecutive pancreaticoduodenectomy cases performed at the Surgery Department of Iwakuni Clinical Center, from April 2008 to May 2018, were included. Preoperative patient data and postoperative complication data were collected. RESULTS: Of the 108 patients (male=65; female=43; mean age=70 years), 41 (37.9%) had indication for pancreaticoduodenectomy due to pancreatic carcinoma. Grade B or higher POPF was diagnosed in 32 patients (29.6%). In the multivariate analysis, body mass index ≥22 kg/m2 [odds ratio (OR)=5.24; p=0.005], CONUT score ≥4 (OR=3.28; p=0.042), non-pancreatic carcinoma (OR=47.17; p=0.001), and a low computed tomographic contrast attenuation value (late/early ratio) (OR=4.39; p=0.029) were independent risk factors for POPF. CONCLUSION: Patients with high CONUT score are at high risk for POPF. Preoperative nutritional intervention such as immunonutrition might help reduce the POPF risk in these patients.

Adequacy evaluation of the annual colonoscopic surveillance and individual difference of disease phenotypes in Lynch syndrome.

BACKGROUND: Regular endoscopic surveillance for Lynch syndrome is reported to reduce colorectal cancer (CRC)-related mortality. However, the appropriate surveillance intervals are still unclear. We evaluated the adequacy of annual colonoscopy and investigated the differences in tumor occurrence rates between individual patients. METHODS: In total, 25 patients with Lynch syndrome who underwent colonoscopic surveillance between 2007 and 2016 at the Iwakuni Clinical Center were included. We retrospectively investigated the surveillance frequency and the clinical features associated with tumor development. RESULTS: Colonoscopic surveillance was performed every 397 days on average. A total of 101 tumors, including 8 intramucosal carcinomas and 15 carcinomas, were observed within the study period. Annual colonoscopy detected six malignancies, including a carcinoma requiring surgery. Tumor incidence was associated with tumor existence in the initial colonoscopies (P = 0.018). Patients with a tumor occurrence rate of 0.4 tumors per year during our observation period were significantly more likely to have malignancies detected during regular surveillance than patients who had a lower occurrence rate (P < 0.001). Malignancy occurrence rate was strongly associated with tumor occurrence rate (P < 0.001, R2 = 0.44). CONCLUSIONS: Annual colonoscopic surveillance for Lynch syndrome patients was effective in reducing the risk of CRC progression, but was insufficient to completely avoid surgery. Because the tumor occurrence rate differed substantially between individuals, more intensive surveillance was required for high-risk patients.

Safety of Surgical Treatment for Elderly Patients with Gallbladder Carcinoma.

Gallbladder carcinoma (GBC) is a common malignancy with a poor prognosis. With the average life expectancy increasing globally, the incidence of GBC is predicted to increase as well. We investigated the safety and feasibility of surgical treatment for elderly patients with GBC. We retrospectively compared clinical pathological data and treatment outcomes in 45 consecutive GBC patients (23 patients ≥ 75 years [elderly group] and 22 patients < 75 years [younger group]) who underwent curative resection at the Iwakuni Center from January 2008 to December 2017. The proportion of preoperative comorbidities and anticoagulant use was significantly higher in the elderly group. The American Society of Anesthesiologists score was higher in the elderly versus the younger group, and the elderly group had significantly shorter operation times. Reduced activities of daily living was more common in the elderly versus younger group. The percentage of radical resection and overall 3-year survival (66.6% younger vs. 64.4% elderly) were similar between the groups. Controlling Nutritional Status (CONUT) score ≥ 3 and R0 resection were identified as prognostic factors for overall survival rate among all patients. After careful patient selection.

Pancreatic Ductal Adenocarcinoma in Remnant Pancreas after Pancreaticoduodenectomy for Acinar Cell Carcinoma: A Case Report.

We report a case of a pancreatic ductal adenocarcinoma (PDAC) in the remnant pancreas of a 78-year-old man after pancreaticoduodenectomy for acinar cell carcinoma, a relatively rare pancreatic neoplasm. After diagnosis of pancreatic carcinoma, subtotal stomach-preserving pancreaticoduodenectomy was performed. The pathological diagnosis was acinar cell carcinoma of the pancreas (disease stage IA, pT1, pN0, M0), without regional lymph node invasion. Cancer antigen 19-9 levels gradually increased during the 22 months after surgery, and computed tomography showed two solid tumors, 1.1 and 2.1 cm in diameter, at the site of the remnant pancreas. Endoscopic ultrasound fine-needle aspiration revealed pancreatic ductal adenocarcinoma. The tumor cells were not immunoreactive for trypsin. Both tumors were diagnosed as PDAC of the remnant pancreas. The patient declined curative resection, and chemoradiotherapy was started as alternative treatment. The patient died 28 months after surgery. Because this is an extremely rare case, additional cases and studies are needed in order to clarify its pathogenesis.