Accurate categorization and rapid pathological diagnosis correction with Micro-Raman technique in human lung adenocarcinoma infiltration level.

Background: In the context of surgical interventions for lung adenocarcinoma (LADC), precise determination of the extent of LADC infiltration plays a pivotal role in shaping the surgeon's strategic approach to the procedure. The prevailing diagnostic standard involves the expeditious intraoperative pathological diagnosis of areas infiltrated by LADC. Nevertheless, current methodologies rely on the visual interpretation of tissue images by proficient pathologists, introducing an error margin of up to 15.6%. Methods: In this study, we investigated the utilization of Micro-Raman technique on isolated specimens of human LADC with the objective of formulating and validating a workflow for the pathological diagnosis of LADC featuring diverse degrees of infiltration. Our strategy encompasses a thorough pathological characterization of LADC, spanning different tissue types and levels of infiltration. Through the integration of Raman spectroscopy with advanced deep learning models for simultaneous diagnosis, this approach offers a swift, precise, and clinically relevant means of analysis. Results: The diagnostic performance of the convolutional neural network (CNN) model, coupled with the microscopic Raman technique, was found to be exceptional and consistent, surpassing the traditional support vector machine (SVM) model. The CNN model exhibited an area under the curve (AUC) value of 96.1% for effectively distinguishing normal tissue from LADC and an impressive 99.0% for discerning varying degrees of infiltration in LADCs. To comprehensively assess its clinical utility, Raman datasets from patients with intraoperative rapid pathologic diagnostic errors were utilized as test subjects and input into the established CNN model. The results underscored the substantial corrective capacity of the Micro-Raman technique, revealing a misdiagnosis correction rate exceeding 96% in all cases. Conclusions: Ultimately, our discoveries highlight the Micro-Raman technique's potential to augment the intraoperative diagnostic precision of LADC with varying levels of infiltration. And compared to the traditional SVM model, the CNN model has better generalization ability in diagnosing different infiltration levels. This method furnishes surgeons with an objective groundwork for making well-informed decisions concerning subsequent surgical plans.

A human serum albumin-indocyanine green complex offers improved tumor identification in fluorescence-guided surgery.

Background: Complete tumor removal is critical for achieving a good prognosis in patients but remains challenging for surgeons. Near-infrared fluorescence-guided surgery (NIRFGS) enables surgeons to accurately localize tumors in real time and facilitates accurate resection. Indocyanine green (ICG) has been approved by the U.S. Food and Drug Administration and the National Medical Products Administration for many years. Although the application of ICG has progressed for a variety of surgeries, there are inherent limitations to ICG, including poor water solubility and photostability, short blood half-life, and aggregation in blood, resulting in poor imaging performance. We found that mixing ICG with human serum albumin (HSA) preoperatively and then injecting it can improve the imaging performance. Methods: We prepared fluorescent probes by combining ICG with HSA and identified their optimal ratio via in vitro absorption measurement and emission spectrum characterization of ICG-HSA complex with different mixing ratios and concentration gradients. Subsequently, under the optimal ratio and clinical simulated concentration, we conducted dynamic change analysis of the fluorescence spectral properties after mixing. We then compared the uptake of ICG-HSA in vitro for two different cell types and the imaging performance of different molar ratios of ICG and HSA in mouse models. Results: Through in vitro absorption and emission spectrum characterization of ICG-HSA mixtures with different mixing ratios and concentration gradients, the optimal ratio of the mixture was obtained (ICG:HSA =4:5). Using this ratio, clinical simulated concentration, and mixing, we completed the dynamic change analysis of the fluorescence spectrum properties. The results verified that HSA can improve the dispersion and stability of ICG in aqueous solution, reduce the proportion of free-state ICG, and thus improve the biodistribution. Moreover, the fluorescence performance of ICG was improved. ICG-HSA and ICG uptake in MDA-MB-231 cells and imaging in vivo showed that HSA increased the enrichment of ICG in tumor compared to ICG alone (ICG-HSAfluorescence intensity =237.3±10.7 vs. ICGfluorescence intensity =127.1±10.7). Compared with ICG alone, ICG-HSA provided a clearer tumor boundary and higher tumor-to-background ratio (TBR) (ICG-HSATBRmax 3.49±0.56 vs. ICGTBRmax 1.94±0.23). Conclusions: This study suggests that ICG-HSA can achieve higher tumor-to-background contrast with shorter time and can provide an overall superior imaging performance compared to ICG alone, thus exhibiting considerable potential for clinical application.

Rapid visualization of PD-L1 expression level in glioblastoma immune microenvironment via machine learning cascade-based Raman histopathology.

INTRODUCTION: Combination immunotherapy holds promise for improving survival in responsive glioblastoma (GBM) patients. Programmed death-ligand 1 (PD-L1) expression in immune microenvironment (IME) is the most important predictive biomarker for immunotherapy. Due to the heterogeneous distribution of PD-L1, post-operative histopathology fails to accurately capture its expression in residual tumors, making intra-operative diagnosis crucial for GBM treatment strategies. However, the current methods for evaluating the expression of PD-L1 are still time-consuming. OBJECTIVE: To overcome the PD-L1 heterogeneity and enable rapid, accurate, and label-free imaging of PD-L1 expression level in GBM IME at the tissue level. METHODS: We proposed a novel intra-operative diagnostic method, Machine Learning Cascade (MLC)-based Raman histopathology, which uses a coordinate localization system (CLS), hierarchical clustering analysis (HCA), support vector machine (SVM), and similarity analysis (SA). This method enables visualization of PD-L1 expression in glioma cells, CD8+ T cells, macrophages, and normal cells in addition to the tumor/normal boundary. The study quantified PD-L1 expression levels using the tumor proportion, combined positive, and cellular composition scores (TPS, CPS, and CCS, respectively) based on Raman data. Furthermore, the association between Raman spectral features and biomolecules was examined biochemically. RESULTS: The entire process from signal collection to visualization could be completed within 30 min. In an orthotopic glioma mouse model, the MLC-based Raman histopathology demonstrated a high average accuracy (0.990) for identifying different cells and exhibited strong concordance with multiplex immunofluorescence (84.31 %) and traditional pathologists' scoring (R2 ≥ 0.9). Moreover, the peak intensities at 837 and 874 cm-1 showed a positive linear correlation with PD-L1 expression level. CONCLUSIONS: This study introduced a new and extendable diagnostic method to achieve rapid and accurate visualization of PD-L1 expression in GBM IMB at the tissular level, leading to great potential in GBM intraoperative diagnosis for guiding surgery and post-operative immunotherapy.

Study on the application value of fluorescent laparoscopy in pancreatic tumor surgery.

Background: Fluorescent laparoscopy is rarely used in pancreatic surgery. The aim of this study was to investigate the value of fluorescent laparoscopy in pancreatic tumor surgery. Methods: A total of 19 patients with pancreatic tumors who were treated in the Department of Hepatobiliary Surgery at the First Affiliated Hospital of Wannan Medical College from January 2021 to August 2022 were selected. Fluorescent laparoscopy was used intraoperatively, and the imaging characteristics of different tumors were recorded and analyzed. Results: Among the 19 participants, postoperative pathology confirmed 12 cases of pancreatic cancer (8 cases of moderately differentiated adenocarcinoma, 3 cases of moderately-poorly differentiated adenocarcinoma, and 1 case of acinar cell carcinoma), 4 cases of pancreatic cystic tumors (1 case of microcystic serous cystadenoma, 1 case of serous cystadenoma, 1 case of solid pseudopapillary tumor, and 1 case of solid-cystic pseudopapillary tumor), 1 case of pancreatic neuroendocrine tumor (G1 stage), and 2 cases of inflammatory lesions. There were 8 cases of pancreaticoduodenectomy, 6 cases of distal pancreatectomy, 3 cases of middle pancreatectomy, 1 case of local pancreatectomy, and 1 case of duodenum-preserving pancreatic head resection. One minute after intravenous injection of indocyanine green (ICG), 10 of the 12 patients with pancreatic cancer showed tumor peritumor imaging; 2 cases of pancreatic serous cystic tumors did not show imaging; 2 cases of solid pseudopapillary tumors had tumor body imaging; 1 case of neuroendocrine tumor had tumor body imaging, with complete fluorescence imaging after specimen dissection; there were 2 cases pathologically confirmed as inflammatory lesions, 1 case with tumor body imaging, and 1 case with capsule imaging. Conclusions: By reasonably controlling the administration time and dose of ICG during surgery, some pancreatic tumors can be fluorescently imaged, which is beneficial for intraoperative tumor localization and margin determination.

Combined indocyanine green and medical glue enables stable and precise position in animal studies: promising for fluorescence-guided pulmonary ground glass nodule resection.

Background: Accurate preoperative localization of pulmonary nodules is crucial for surgical treatment. The use of indocyanine green (ICG) for localization is prone to thoracic contamination and spread, resulting in the eventual failure of localization. By using medical glue combined with ICG, we can accurately and permanently locate various tissues in animal study, which can provide evidences for clinical translations. Methods: A series of medical glue and ICG volume ratios of 2:3, 3:3, 4:3, 6:3, and 9:3 were mixed and injected immediately into subcutaneous tissues of BALB/c nude mice; either medical glue or ICG was injected singly in the control group. Fluorescence intensity over time and boundary sharpness were investigated to determine the optimal ratio. Then, fluorescence guided resection of tissue was performed ex vivo on the pig intestine utilizing optimal ratio. Further, localization agents with the optimal ratio were injected into the organs of living mice, and fluorescence imaging for accurate positioning was performed 24 hours later. Results: The localization agents with a volume ratio of 4:3 showed the best boundary sharpness and the strongest photostability. With the guidance of fluorescence navigation, the marked tissues were accurately separated and removed from the surrounding tissue both on mice and on pig intestines. In the organs of living mice, the localization agents (ratio 4:3) realized accurate positioning of marked tissues. Additionally, the medical glue limited the diffusion of ICG, promising to enable more stable and precise positioning of the nodules during surgery. Conclusions: The combination of ICG and medical glue presents a superior approach when compared to the individual use of either ICG or medical glue. This technique offers enhanced precision and durability and sealed the wound, thereby mitigating the risk of pneumothorax following puncture procedures. This innovative technique optimizes the properties of medical adhesive to augment tissue density while harnessing the real-time fluorescent endoscopic marking capabilities of ICG during surgical interventions. By employing this innovative technique, it holds significant promise for augmenting the accuracy of pulmonary nodule localization in thoracoscopic surgery within future clinical applications.

A Phase Ib Study of the Simmitecan Single Agent and in Combination With 5-Fluorouracil/Leucovorin or Thalidomide in Patients With Advanced Solid Tumor.

Background: Simmitecan is a potent inhibitor of topoisomerase I with anti-tumor activity. This phase Ib trial was conducted to investigate the safety and anti-tumor effect of simmitecan alone or in combination with other drugs. Methods: Eligible patients with advanced solid tumor had no further standard treatment options. Patients were allocated to receive simmitecan alone, simmitecan in combination with 5-fluorouracil (5-FU)/leucovorin (LV), or simmitecan in combination with thalidomide, 14 days a cycle, until disease progression or unacceptable toxicity occurred. Results: A total of 41 patients were enrolled, with a median age of 55 (range 29-69) years. Among them, 13 patients received simmitecan monotherapy, 10 received simmitecan + 5-FU/LV, and 18 received simmitecan + thalidomide. No dose-limiting toxicity occurred. Overall, the most common grade 3/4 adverse event (AE) was neutropenia (46.2, 70.0, and 88.9%, respectively, in simmitecan, simmitecan + 5-FU/LV, and simmitecan + thalidomide cohorts), and treatment-related severe AEs included anemia and febrile neutropenia (7.7% each in simmitecan cohort), diarrhea (10% in simmitecan +5-FU/LV cohort), and febrile neutropenia (5.6% in simmitecan + thalidomide cohort). The majority of patients (24/41, 58.3%) had progressed on prior irinotecan; nevertheless, partial response was achieved in one colorectal cancer patients treated with simmitecan + thalidomide. The disease control rates of simmitecan, simmitecan + 5-FU/LV, and simmitecan + thalidomide cohorts were 46.2, 80.0, and 61.1%, respectively. Conclusion: This study demonstrated a manageable safety profile of simmitecan as a single agent or as part of a combination therapy. There have not been any safety concerns with simmitecan in combination when compared to simmitecan alone. Simmitecan + 5-FU/LV regimen seemed to have a better efficacy. Nonetheless, the efficacy of this regimen needs to be further explored in the subsequent study.

Based on lapatinib innovative near-infrared fluorescent probes targeting HER1/HER2 for in vivo tumors imaging.

Human epidermal growth factor receptors HER1 and HER2, overexpressed in non-small cell lung cancer, colorectal cancer, liver cancer, are key regulators of tumor cells proliferation, invasion and survival. Many antibody- or peptide-based fluorescent probes targeted to HER1/HER2 are under active clinical evaluation. However, the effective small-molecule near-infrared (NIR) fluorescent probes are still lacking. Herein, with the strategy of drug repurposing, we developed a series of HER1/HER2-targeted probes YQ-H (01-07) composed of fluorophore (a cyanine dye, MPA), linker unit and targeted unit (lapatinib, LAP). The synthesized probes were evaluated in vitro and in vivo tumor specificity/affinity. Specially, the probe YQ-H-06 exhibited optimal pharmacokinetic property and tumor/normal tissue ratio (T/N) in tumor-bearing mice. Furthermore, we evaluated the targeting capability of YQ-H-06 in orthotopic colorectal cancer and orthotopic hepatic carcinoma mice. It was indicated that YQ-H-06 had the characteristic of great biosafety, favorable pH and chemical stability, as well as provided excellent tumor contrast in orthotopic murine tumor models. The NIR fluorescent probe YQ-H-06 will shed light on tumor detection and fluorescence-guided surgery.

Unexpected detection of a submillimeter early hepatocellular carcinoma focus by intraoperative near-infrared fluorescence imaging-a case report.

Background: Prognosis of hepatocellular carcinoma (HCC) is closely related to residual tumor cells and tissues after tumor resection. Thus, close monitoring to ensure complete removal of residual tumor is fundamental. In this regard, intraoperative near-infrared fluorescence (NIRF) imaging has been of great assistance to surgeons for precision cancer surgeries. However, up to now, the identification of tiny lesions has not been reported. Herein, we report our findings on the case of an ultra-small HCC focus of about 430 µm that was successfully detected using NIRF during real-time monitored liver cancer surgery. The patient had a background of hepatitis B cirrhosis, which is the most phenomenon in China. Surgeons usually unable to distinguish sclerotic nodules from small tumor tissue with the naked eyes. Case Description: A 55-year-old man with chronic hepatitis B infection was preoperatively diagnosed with a space-occupying liver lesion. A fluorescence signal was detected on the surface of the liver through the NIRF imaging system which had not been found by preoperative computed tomography (CT) and ultrasound examination. We subsequently tested the residual liver surface and observed a high signal point, less than 1 mm in the right anterior lobe of the liver. Histopathological examination revealed that the tiny fluorescent spot belong to an early HCC focus. Conclusions: Based on these results, we think indocyanine green (ICG)-NIRF imaging may be used as a routine intraoperative detection method for liver cancer surgery in order to remove any residual tumor cells and tissue, hence minimizing further risk of remnant tumor regrowth.

Clinical application of indocyanine green fluorescence navigation technology to determine the safe margin of advanced oral squamous cell carcinoma.

Background: Advanced oral squamous cell carcinoma (OSCC) has large lesions and deep infiltration, and the control of safe surgical margins was difficult. If residual tumor remains after incomplete tumor resection, it can lead to local tumor recurrence or even distant metastasis. This study sought to investigate the clinical application of indocyanine green (ICG)-based near-infrared fluorescence (NIF) molecular imaging in the intraoperative detection of surgical margins of advanced OSCC. Methods: Twenty-nine patients with advanced OSCC treated at the First Ward of Oral and Maxillofacial Surgery, Nanjing Stomatological Hospital were divided into the ICG group and non-ICG group. In the ICG group, the tumors were removed with the assistance of ICG fluorescence navigation technology. In the non-ICG group, the tumors were removed with conventional methods, and the cutting-edge tissues of the two groups underwent frozen biopsies. The margin abnormality rates were calculated and compared. Results: Under the excitation of NIF in the ICG group, tumor fluorescence development was observable in all lesions, and the tumor boundary was clear. The abnormal rates of the incisional margin in the ICG group and non-ICG group were 0.78% and 6.25%, respectively (P<0.05). Conclusions: ICG-mediated NIF imaging technology provides a new method for observing and completely resecting tumors under direct vision during operation, and finding residual tumors at the cutting edge in time. These results will inform the treatment of advanced OSCC.

A study on setting standards for near-infrared fluorescence-image guided surgery (NIRFGS) time lapse monitoring based on preoperative liver function assessment.

Background: This study aimed to explore the relationship between the fluorescence intensity of indocyanine green (ICG) in near-infrared fluorescence guided surgery (NIRFGS) and preoperative liver function indicators. Methods: A total of 12 4T1 tumor-bearing mice were used for model establishment. Intraperitoneal injection (i.p.) of 20% carbon tetrachloride (CCl4) corn oil solution (50 µL) was given to mice in the liver injury model group, 24 hours after injection, the model was established, while the control group received 0% CCl4 corn oil solution (50 µL) (n=6 for each group). Additionally, doses of 8 mg/kg and 1 mg/kg of free ICG were injected intravenously (i.v.) (n=3 in each group). Fluorescence was imaged in vivo using an NIR fluorescence imaging system at different time points (1, 2, 4, 8, 12, 24, 48, and 72 h) after injection. Results: The absolute fluorescence intensity of mice in the liver injury model group was stronger than that in the control group. Mice in the liver injury model group had the same clearance rate of ICG from the tumor as normal mice. However, the background clearance rate was slower than that of normal mice, which prolonged the optimal tumor to background ratio (TBR) time. Correlation analysis was also used to determine which preoperative liver function parameters were most correlated with hepatic ICG clearance. Conclusions: Liver injury does not significantly affect the maximum TBR, but prolongs the optimal TBR time, and at the same time, a wider and more stable surgical window will appear. This study showed that a prolonged surgical start time is feasible according to preoperative liver function testing using NIR fluorescence imaging technology.

Advantages of using indocyanine green in liver transplantation: a narrative review.

Objective: To assess the role of indocyanine green in liver transplantation and to lay the foundation for its application in clinical practice. Background: Liver transplantation offers the best prognosis for patients with end-stage liver disease. However, this invasive procedure involves multiple well-known challenges, including complications due to graft rejection and dysfunction, surgical risks, and critical postoperative management. Intraoperative methods to assess graft function rely on conventional methods, such as blood chemistries and Doppler ultrasound. However, these methods are limited in their abilities to assess liver conditions, predict functional outcomes of the graft, and prevent surgical complications. Thus, identifying a more effective and comprehensive detection method is necessary. Methods: The information used to write this narrative review was collected from the references' opinions and conclusions. Conclusions: Indocyanine green can effectively monitor blood flow during surgery, evaluate donor graft function, and monitor the recipients functional status during and after surgery. It may also help surgeons to predict the prognosis of patients throughout the liver transplantation process, from assessing patients for liver transplantation status to postoperative management. Therefore indocyanine green should be routinely used in liver transplantation to help re-organize the transplant waiting list and improve the surgical outcomes of liver transplantation patients.

Application of an indocyanine green surgical fluorescence imaging system in sentinel lymph node biopsy of acral malignant melanoma.

BACKGROUND: Regional lymph node status is an independent influencing factor for the prognosis of acral malignant melanoma, and the accuracy of sentinel lymph node biopsy (SLNB) is directly related to the judgment of regional lymph node status. This study aimed to explore the application value of indocyanine green (ICG) surgical fluorescence imaging system in the SLNB of acral malignant melanoma. METHODS: A total of 34 patients with acral malignant melanoma were admitted to the Department of Burn and Plastic Surgery in Jiangsu Provincial People's Hospital from January 2020 to March 2020. Among these patients, 22 required SLNB. ICG and methylene blue (MB) were combined to intraoperatively trace the sentinel lymph nodes (SLNs). The total number of SLNs detected during the operation was counted. We compared the number, detection rate, as well as the detection rate and false negative rate of positive SLNs of SLNs detected by ICG, MB, and ICG combined with MB. RESULTS: A total of 56 SLNs were detected in the 22 patients, among which 55 were detected by ICG (98%), 41 were detected by MB (71%), and 56 (100%) were detected by ICG combined with MB, and the average number of SLNs were 2.5, 1.64, and 2.55, respectively. A total of nine SLNs were detected, of which nine were detected by ICG (100%), seven by MB (78%), and nine by ICG combined with MB (100%). Patients with negative SLNs had no recurrence at the 6-month follow-up. CONCLUSIONS: Compared with MB, the ICG fluorescent imaging system can improve the detection rate of SLNs in patients with acral malignant melanoma. Also, ICG combined with MB was superior to ICG alone.

Application of an indocyanine green-mediated fluorescence imaging navigation system in detecting mice tumors.

BACKGROUND: Surgical operation plays an important role in the treatment of cancer. The success of the operation lies in the complete removal of the primary and disseminated tumor tissue while preserving the normal tissue. The development of optical molecular image navigation technology has provided a new option for intraoperative tumor visualization. In this study, a fluorescence imaging navigation system was used to detect the diameter of mice tumors and provide experimental evidence for the further development of digital diagnosis and treatment equipment. METHODS: The minimum detection concentration in vitro of the fluorescence imaging navigation system for indocyanine green (ICG) was first detected, then 120 female Institute of Cancer Research (ICR) mice and 120 female BALB/c nude mice were randomly divided into three groups by weight, high-dose (H, 4 mg/kg), middle-dose (M, 2 mg/kg), and low-dose (L, 1 mg/kg) groups of ICG solution. After inoculating solid tumors, high, medium, and low doses of ICG were injected via the tail vein, and the tumor diameter was measured by a fluorescence imaging navigation system and vernier caliper within 24 hours of injection. RESULTS: The minimum detectable diameter of the system could reach 0.2 mm compared with the vernier caliper, and the actual measurement error was within 0.2 mm. CONCLUSIONS: A fluorescence imaging navigation system has high accuracy and sensitivity in the application of tumor detection, which may assist the clinical diagnosis and treatment of tumors.

A pilot study of near-infrared fluorescence guided surgery for primary tumor localization and lymph node mapping in colorectal cancer.

BACKGROUND: This pilot study aimed to evaluate the feasibility of near-infrared fluorescence imaging for primary tumor localization, lymph node mapping, and metastatic lymph node detection in colorectal cancer (CRC) using indocyanine green (ICG). METHODS: A total of 11 patients with CRC were prospectively enrolled. ICG (25 mg dissolved in 30 mL sterile water) was intravenously injected preoperatively, and the fluorescence intensity of the primary tumor, lymph nodes, and normal tissues, as well as the signal-to-background ratio (SBR) and contrast-to-noise ratio (CNR) were measured at 0.5, 1, 2, 4, and 24 h after ICG injection. RESULTS: The primary tumor could be located intraoperatively, and the tumor boundary was clear at 2-4 h. There was good contrast in the fluorescence intensity between tumor and normal tissues (SBR =2.11±0.36, CNR =8.74±0.35). The lymph node detection rate was 95% (38/40), and the SBR threshold of lymph nodes was 1.13. CONCLUSIONS: This pilot study showed that primary tumor localization and lymph node mapping in CRC is feasible using near-infrared fluorescence imaging technology, though metastatic lymph nodes cannot be discriminated from benign ones. In addition, cancer nodules missed by both white light mode and palpation by the surgeon were unexpectedly found, resulting in a change in the surgical prognosis in 9.1% (1/11) of patients.

Integrated analysis of single-cell RNA-seq and bulk RNA-seq reveals distinct cancer-associated fibroblasts in head and neck squamous cell carcinoma.

BACKGROUND: The heterogeneity of cancer-associated fibroblasts (CAFs) in head and neck squamous cell carcinoma (HNSCC) has been widely acknowledged, but has not yet been elucidated. The potential roles and clinical relevance of CAFs subclusters in HNSCC progression remain obscure. METHODS: In this study, we combined single-cell and bulk tissue transcriptome profiles of HNSCC with clinical data from The Cancer Genome Atlas (TCGA). The Seurat package was used to perform single-cell RNA-seq analysis to distinguish distinct CAFs subtypes. Prognostic relevance of several CAFs markers was assessed and functional analysis was also performed. RESULTS: We identified eight CAFs subclusters; of these, seven showed enhanced expression levels in HNSCC tumor tissues compared to normal tissue, and three (clusters 0, 3, and 4) were associated with poorer overall survival. Further functional analysis revealed that cluster 0 was characterized by myofibroblasts with high alpha smooth muscle actin (aSMA) expression and enrichment in smooth muscle contraction. The cluster 3 exhibited expression of extracellular matrix (ECM)-related genes and was enriched in epithelial-mesenchymal transition (EMT)-related gene sets. Cluster 4 expressed high levels of the major histocompatibility complex (MHC) class II family, which was characterized as antigen-presenting CAFs. CONCLUSIONS: We determined CAFs heterogeneity in HNSCC. 8 CAFs subclusters were recognized and 3 of which were prognosis related. The 3 CAFs subclusters showed distinct phenotypes enriched in myofibroblast function, ECM remodeling and antigen-presenting function respectively.

Comparative study on the diagnostic value of intravenous/peritumoral injection of indocyanine green for metastatic lymph node location in patients with head and neck squamous cell carcinoma (HNSCC).

BACKGROUND: Accurate assessment of regional lymph node (LN) status is essential for the treatment of head and neck squamous cell carcinoma (HNSCC) patients. In this study, we aimed to compare the difference between intravenous injection of indocyanine green (ICG) and peritumoral injection of ICG in the location of metastatic LNs. METHODS: Twenty-nine patients were enrolled in this study with 13 patients receiving intravenous injection of ICG and 16 patients receiving peritumoral injection of ICG. During the surgery, the fluorescence-positive LNs in vivo were sent to undergo frozen section after fluorescence intensity was recorded. After the cervical LN dissection, all LNs were sorted by region, and the fluorescence intensity was recorded before the LNs were sent for paraffin section. RESULTS: During the surgery, both intravenous or peritumoral injections with near-infrared (NIR) fluorescence imaging of ICG had their respective pros and cons in vivo, with the sensitivity and specificity being 62.5%/75% and 98.1%/89.1% respectively. After the surgery, both methods could reduce the pathological workload by preselecting the LNs at-risk in the premise of accurate assessing the cervical LN stage. However, intravenous ICG administration was more valuable in determining all types of LN status according to the fluorescence intensity [area under the curve (AUC): 0.91 vs. 0.78, P<0.001]. CONCLUSIONS: With the assistance of NIR fluorescence imaging using ICG, both administration methods could reduce the postoperative complication and the pathological workload, whereas the intravenous mode of ICG administration is superior in application value.

Immune Checkpoints in Viral Infections.

As evidence has mounted that virus-infected cells, such as cancer cells, negatively regulate the function of T-cells via immune checkpoints, it has become increasingly clear that viral infections similarly exploit immune checkpoints as an immune system escape mechanism. Although immune checkpoint therapy has been successfully used in cancer treatment, numerous studies have suggested that such therapy may also be highly relevant for treating viral infection, especially chronic viral infections. However, it has not yet been applied in this manner. Here, we reviewed recent findings regarding immune checkpoints in viral infections, including COVID-19, and discussed the role of immune checkpoints in different viral infections, as well as the potential for applying immune checkpoint blockades as antiviral therapy.

Kinetics of indocyanine green: Optimizing tumor to normal tissue fluorescence in image-guided oral cancer surgery applications.

BACKGROUND: The study aimed to define indocyanine green (ICG) kinetics to determine the optimal ICG dose and surgical time for near-infrared fluorescence-guided oral cancer surgery. METHODS: Spectrometer and grayscale digital imaging were used to quantify the ICG kinetics in 12 patients with oral cancer. The fluorescence intensity and signal-to-background ratio (SBR) of tumor and normal tissue were tested at 1, 6, and 24 hours after ICG injection. RESULTS: The greatest contrast in the fluorescence intensity between tumor and normal tissue was observed at 6 hours (P < .01), and of three dose groups (0.5, 0.75, and 1.0 mg/kg), 0.75 mg/kg showed the highest SBR (2.06 ± 0.23) after ICG injection. CONCLUSIONS: Fluorescence quantification based on spectrometry and grayscale imaging could be effective in determining the optimal ICG dose and surgical time after ICG injection in this cohort of patients with oral cancer.

Method for Real-Time Tissue Quantification of Indocyanine Green Revealing Optimal Conditions for Near Infrared Fluorescence Guided Surgery.

Near infrared fluorescence guided surgery (NIRFGS) offers better distinction between cancerous and normal tissues compared to surgeries relying on a surgeon's senses of sight and touch. Because of the greater accuracy in determining tumor tissue margins, NIRFGS within clinics continues to grow. However, NIRFGS lacks standardization of the indocyanine green (ICG) dose and the preoperative period allowed after ICG administration. In an aim to find optimal doses and preoperative periods for NIRFGS standardization, we developed a method that quantitatively determines ICG levels within tissues in real-time. We find that not only do the dose and the preoperative periods influence tumor-to-background ratios (TBRs), but both also heavily influence subject-to-subject variances of these ratios. Optimal detection conditions are observed when larger than typical ICG doses are administered and longer than typical preoperative periods are allowed. Larger doses lead to increased TBRs, but longer preoperative periods are necessary to reduce TBR variances to those observed when using smaller doses. Our results suggest that a clinical investigation into maximum tolerable ICG doses and prolonging preoperative periods in NIRFGS is warranted.