Real-time fluorescence image-guided gastrointestinal oncologic surgery:Towards a new era

Technological improvements are crucial in the evolution of surgery.Real-time fluorescence-guided surgery(FGS)has spread worldwide,mainly because of its usefulness during the intraoperative decision-making processes.The success of any gastrointestinal oncologic resection is based on the anatomical identification of the primary tumor and its regional lymph nodes.FGS allows also to evaluate the blood perfusion at the gastrointestinal stumps after colorectal or esophageal resections.Therefore,a reduction on the anastomotic leak rates has been postulated as one of the foreseeable benefits provided by the use of FGS in these procedures.Although the use of fluorescence in lymph node detection was initially described in breast cancer surgery,the technique is currently applied in gastric or splenic flexure cancers,as they both present complex and variable lymphatic drainages.FGS allows also to perform intraoperative lymphograms or sentinel lymph node biopsies.New applications of FGS are being developed to assist in the detection of peritoneal metastases or in the evaluation of the tumor resection margins.The present review aims to provide a general overview of the current status of real-time FGS in gastrointestinal oncologic surgery.We put a special focus on the different applications of FGS,discussing the main findings and limitations found in the contemporary literature and also the promising near future applications.

Near-infrared fluorescence imaging of a solitary fibrous tumor of the pancreas using methylene blue

A 67-year-old female presented with unexplained abdominal pain. A contrast-enhanced computed tomography scan of the abdomen incidentally revealed a mass in the uncinate process of the pancreas. This mass was resected and based on histopathological findings, diagnosed as a solitary fibrous tumor (SFT) of the pancreas. A SFT is an extremely rare benign mesenchymal tumor that in 65% of cases affects the visceral pleura but can also affect extra-pleural sites. The intraoperative demarcation of pancreatic tumors, such as SFTs, can bechallenging. In this report, the first clear intraoperative identification of a SFT of the pancreas in a human was shown using near-infrared fluorescence and methylene blue.

Near-infrared fluorescence sentinel lymph node detection in gastric cancer: A pilot study

AIM: To investigate feasibility and accuracy of near-infrared fluorescence imaging using indocyanine green: nanocolloid for sentinel lymph node (SLN) detection in gastric cancer.METHODS: A prospective, single-institution, phase I feasibility trial was conducted. Patients suffering from gastric cancer and planned for gastrectomy were included. During surgery, a subserosal injection of 1.6 mL ICG:Nanocoll was administered around the tumor. NIR fluorescence imaging of the abdominal cavity was performed using the Mini-FLARE™ NIR fluorescence imaging system. Lymphatic pathways and SLNs were visualized. Of every detected SLN, the corresponding lymph node station, signal-to-background ratio and histopathological diagnosis was determined. Patients underwent standard-of-care gastrectomy. Detected SLNs outside the standard dissection planes were also resected and evaluated.RESULTS: Twenty-six patients were enrolled. Four patients were excluded because distant metastases were found during surgery or due to technical failure of the injection. In 21 of the remaining 22 patients, at least 1 SLN was detected by NIR Fluorescence imaging (mean 3.1 SLNs; range 1-6). In 8 of the 21 patients, tumor-positive LNs were found. Overall accuracy of the technique was 90% (70%-99%; 95%CI), which decreased by higher pT-stage (100%, 100%, 100%, 90%, 0% for respectively Tx, T1, T2, T3, T4 tumors). All NIR-negative SLNs were completely effaced by tumor. Mean fluorescence signal-to-background ratio of SLNs was 4.4 (range 1.4-19.8). In 8 of the 21 patients, SLNs outside the standard resection plane were identified, that contained malignant cells in 2 patients.CONCLUSION: This study shows successful use of ICG:Nanocoll as lymphatic tracer for SLN detection in gastric cancer. Moreover, tumor-containing LNs outside the standard dissection planes were identified.

A facile phototheranostic nanoplatform integrating NIR-Ⅱ fluorescence/PA bimodal imaging and image-guided surgery/PTT combinational therapy for improved antitumor efcacy

Phototheranostic with highly integrated functions is an attractive platform for cancer management. It remains challenging to develop a facile phototheranostic platform with complementary bimodal imaging and combinational therapy capacity. Herein, the small-molecule cyanine IR780 loaded liposomes have been harnessed as a nanoplatform to simultaneously realize photoacoustic(PA)/the second near-infrared window(NIR-Ⅱ) fluorescence imaging and image-guided surgery/adjuvant photothermal therapy(PTT).This nanoplatform exhibits attractive properties like uniform controllable size, stable dispersibility, NIR-Ⅱ fluorescence emission, photothermal conversion, and biocompatibility. Benefiting from the complementary PA/NIR-Ⅱ fluorescence bimodal imaging, this nanoplatform was successfully applied in precise vasculature delineation and tumor diagnosis. Interestingly, the tumor was clearly detected by NIR-Ⅱ fluorescence imaging with the highest tumor-to-normal-tissue ratio up to 12.69, while signal interference from the liver was significantly reduced, due to the difference in the elimination rate of the nanoplatform in the liver and tumor. Under the precise guidance of the image, the tumor was accurately resected, and the simulated residual lesion after surgery was completely ablated by adjuvant PTT. This combined therapy showed improved antitumor efcacy over the individual surgery or PTT. This work develops a facile phototheranostic nanoplatform with great significance in accurately diagnosing and effectively treating tumors using simple NIR light irradiation.

Dendritic cell vaccination in glioblastoma after fluorescenceguided resection

AIM: To assess whether the addition of a customized, active immunotherapy to standard of care including fluorescence-guided surgery, may provide hints of an improved survival for patients with poor-prognosis, incurable glioblastoma multiform. METHODS: Preliminary to our ongoing, phase-Ⅱ clinical trial, we conducted a small pilot study enrolling five consecutive patients with resectable glioblastoma. In terms of Recursive Partitioning Analysis, four patientswere class Ⅴ and one was class Ⅳ. In all five cases, fluorescence-guided surgery was employed, followed by rapid steroid discontinuation. Patients were then treated with a combination of standard radio-chemotherapy with temozolomide and tumor lysate-pulsed, mature dendritic cell-based vaccinations.RESULTS: Though all five patients ultimately progressed, with any further treatment left to the sole decision of the treating oncologist, active immunotherapy was very well tolerated and induced specific immune responses in all three patients for whom enough material was available for such an assessment. Median progression-free survival was 16.1 mo. Even more important, median and mean overall survival were 27 mo and 26 mo, respectively. Three patients have died with an overall survival of 9 mo, 27 mo and 27.4 mo, while the other two are still alive at 32 mo and 36 mo, the former receiving treatment with bevacizumab, while the latter has now been off therapy for 12 mo. Four of five patients were alive at two years.CONCLUSION: Active immunotherapy with tumor lysate-pulsed, autologous dendritic cells is feasible, safe, well tolerated and biologically efficacious. A phase-Ⅱ study is ongoing to possibly improve further on our very encouraging clinical results.

Laparoscopic resection of gastrointestinal neuroendocrine tumors with special contribution of radionuclide imaging

The surgical treatment of neuroendocrine tumors(NETs) draws on experience and guidelines more than on prospective randomized trials. The incidence of NET is increasing in all parts of the gastrointestinal tract. A variety of classifications introduced over the last decade may have led to difficulties in judging clinical relevance and determining the right surgical strategy. The North American Neuroendocrine Tumor Society and the European Neuroendocrine Tumor Society have developed usable guidelines from the available literature. For more than 20 years laparoscopy has developed as the gold standard for various surgical indications. Nevertheless, few trials have compared open and laparoscopic surgery with regard to NET. This review summarizes the recent literature on surgery for NET and incorporates the evidence on laparoscopy for cancer which might be also applied for NET.

Enabling AIEgens close assembly in tumor-overexpressed protein cluster for boosted image-guided cancer surgery

Development of efficient fluorescent probes that can realize precise fluorescence image-guided cancer surgery(FIGCS)with extremely high tumor-to-normal tissue(T/NT)ratio is urgently desirable.Herein,we report the design and synthesis of an aggregation-induced emission(AIE)-active,peptide-based fluorescence turn-on probe MPA-Ph-R-FFGYSAYPDSVPMMS(MPA-Ph-R-FFGYSA for short),which consists of a new near-infrared emissive AIE luminogen(AIEgen)MPA-Ph-R,a self-assembling peptide sequence“FFG”,and an“active”targeting peptide YSAYPDSVPMMS that can selectively bind to EphA2 protein cluster overexpressed in many cancers.As compared to the control probe MPA-Ph-R-YSA without“FFG”,MPA-Ph-R-FFGYSA exhibits much higher fluorescent brightness and sensitivity in both cellular and in vivo studies on EphA2 cluster detection/imaging,as“FFG”is beneficial to closer assembly of AIEgens in EphA2 cluster,leading to more effective restriction of the intramolecular motion of AIEgen.In vivo studies demonstrate that MPA-Ph-R-FFGYSA is a safe bioprobe and gives excellent performance in FIGCS with a rather high T/NT ratio of^13.4 upon intravenous administration into peritoneal carcinomatosis-bearing mice.This study provides a new strategy of utilizing the close assembly of tumor microenvironment-responsive AIE probes for boost FIGCS.

吲哚菁绿荧光显像技术在肝母细胞瘤精准切除手术中的应用

目的探讨吲哚菁绿(indocyanine green,ICG)介导的近红外光在肝母细胞瘤中的显像特点,以及该技术对术中微小病灶识别、肿瘤切缘界定和术中导航的价值。方法2018年3月至2018年6月由复旦大学附属儿科医院收治的拟切除肝母细胞瘤的患儿8例,术前至少24 h予以静脉注射ICG,术中切肝前进行肝脏微小病灶检测、肿瘤切缘界定和手术导航,切肝后进行切缘病灶检测和肿瘤荧光分型,最终与病理结果对比。结果8例肝母细胞瘤中,男童和女童各4例,年龄5~132个月,平均33个月。术后复发再次手术1例,术前活检化疗后再手术1例,术前经验性化疗后再手术4例,2例一期行肝肿瘤切除术。术中8例患儿肿瘤都呈现明亮荧光显影,与正常肝脏组织边界清晰;1例复发为微小病灶(1.0 cm),但由于病灶位置较深(距离肝脏表面 >1.5 cm),肉眼观察、扪诊和ICG荧光显像未能发现,规则切除肝叶后,ICG识别出复发病灶。根据荧光显影分型,全荧光4例,其中2例肝母细胞瘤一期行肿瘤切除术;1例术前有活检和化疗史的病例;1例为复发病例,其有肝炎和肝轻度硬化病史,同时伴有肝脏弥漫性小结节样影。部分荧光4例,均为术前有经验性化疗的病例。结合肝母细胞瘤的病理分类,胎儿型7例,其中荧光显像为全荧光型4例,部分荧光型3例;混合性胎儿上皮和胚胎上皮型1例,其荧光显像为部分荧光型。所有病灶经ICG分子荧光边界定界,切除肿瘤后,经荧光再测和病理检查,均获得了肿瘤R0切除。结论ICG荧光显影技术在肝母细胞瘤中有较好的显影效果,显影类型与术前有无化疗有一定关系。ICG荧光显像在确定肿瘤边界和保证肿瘤R0切除具有一定优势和重要价值。但ICG荧光显像对深部微小肿瘤灶的识别和在肝硬化病例中的运用存在一定的局限性。

荧光成像术中导航研究进展

荧光成像技术可实时获取手术过程中血管、淋巴结以及肿瘤组织等信息,有助于发现白光条件下无法识别的微小病灶,可精准定位肿瘤部位和边界,辅助医生在术中做出更准确的决策,从而降低手术切缘阳性率。就荧光成像术中导航的发展现状、临床常用的荧光探针及特点、分子荧光探针的制备和临床应用,以及该技术的局限性和应用前景予以综述。

吲哚菁绿在乳腺癌肿瘤坏死模型中的光学成像研究

目的探讨吲哚菁绿(indo cyanine green,ICG)在小鼠乳腺癌肿瘤坏死模型光学成像中的可行性及其效果。方法腋下局部注射95%无水乙醇1μL造成小鼠局部组织坏死后,于尾静脉注射0.5 mg/kg ICG 100μL,通过荧光活体成像系统(in vivo imaging system,IVIS)观察注射ICG后2 h和24 h时ICG的体内分布情况,初步验证ICG的坏死亲和性。通过将人乳腺癌MDA-MB-231荧光素酶基因稳转株MDA-MB-231-Luc细胞接种于裸鼠右侧腋下构建乳腺癌荷瘤小鼠模型。通过尾静脉注射血管破坏性药物考布他汀A4磷酸脂(combretastatin A4 phosphate,CA4P)100 mg/kg 100μL 24 h构建乳腺癌肿瘤坏死模型。对肿瘤坏死小鼠于尾静脉注入0.5 mg/kg ICG 100μL,通过IVIS对荷瘤小鼠分别在注射ICG后2 h和24 h时进行自体荧光及近红外荧光成像,评估ICG在乳腺癌肿瘤坏死模型中的分布及光学成像效果。将小鼠分为对照组、ICG组和ICG+CA4P组,ICG+CA4P组为上述用于光学成像的肿瘤坏死小鼠,对照组与ICG+CA4P组同样建模但仅给予尾静脉注射生理盐水100μL而未注射ICG及CA4P,ICG组与ICG+CA4P组同样建模后仅于尾静脉注入0.5 mg/kg ICG 100μL而未给予CA4P。三组分别于给药后0、3、7和10 d测量肿瘤体积。结果在无水乙醇造成的局部坏死模型中,在尾静脉注射ICG后2 h时,IVIS下见ICG主要分布于肝脏及坏死区域。在24 h时,肝脏内的ICG逐渐代谢排出,而坏死组织处ICG在坏死亲和性的作用下,ICG聚集并潴留在坏死组织中,荧光成像结果中呈现出高信号。在CA4P造成的乳腺癌肿瘤坏死模型中,在注射ICG后24 h时,ICG在种植瘤及转移瘤区域潴留富集,自体荧光及近红外荧光成像结果高度重合。在ICG+CA4P组中,肿瘤的生长受到抑制,与对照组比较,在3、7和10 d时差异均具有统计学意义(均P<0.05),与ICG组比较在7和10 d时差异均具有统计学意义(均P<0.05)。结论ICG可在CA4P介导下的肿瘤坏死模型中高度聚集,可实现良好的光学成像效果,在肿瘤转移早期检测及手术导航中具有良好的应用前景。

光学分子影像导航下精准手术的应用与研究进展

外科手术是肿瘤治疗方案中的重要一环,手术的成功不仅在于完全切除原发及播散的肿瘤组织,同时还要最大限度地保护正常组织,但在实际手术过程中,仅凭肉眼和手感触觉识别肿瘤组织及其边界难度较大,因此漏切或过切现象时有发生。光学分子影像技术能利用荧光物质使肿瘤细胞或组织显影达到可视化,由于具有实时、无创、操作简单等优点,越来越多地被应用于手术导航。利用特有的荧光影像设备和荧光探针,可以使肿瘤与周围正常组织的分界清晰显示,使外科手术逐步达到精准化。近年来,光学分子影像导航下术中肿瘤探测及边界界定、前哨淋巴结探测、术中神经保护等方面均有较多的临床应用及实验研究。

吲哚菁绿荧光成像技术在鼻内镜肿瘤手术中的初步应用

目的:初步探讨吲哚菁绿(indocyanine green,ICG)分子荧光成像技术在鼻内镜下肿瘤手术中的应用价值。方法:以2022年12月—2023年4月间新疆军区总医院耳鼻咽喉头颈外科5例鼻腔鼻窦、眶壁、颅底相关肿瘤患者作为研究对象,其中良性肿瘤3例,恶性肿瘤2例。所有患者皆在ICG分子荧光成像技术指导下完成手术。术前12~24 h按0.5 mg/kg剂量经肘静脉静推ICG;术中通过荧光成像对肿瘤进行标记,术者严格按标记范围、深度清除肿物组织,恶性肿瘤根据病检结果做进一步扩大清理。结果:5例患者在荧光成像技术辅助下,均实现了精准的肿瘤定位;参照荧光标记界限进行切除,对患者均做到了肿瘤的彻底清理或切缘阴性。结论:针对鼻内镜下肿瘤相关手术,ICG分子荧光成像技术不仅能做到实时精准定位,而且能为术者判断肿瘤边界提供依据。因此认为该项技术在鼻内镜肿瘤手术中应具有一定的应用价值。

Current trends and key considerations in the clinical translation of targeted fluorescent probes for intraoperative navigation

The rapid development of fluorescence imaging for intraoperative navigation has spurred further development of targeted fluorescent probes in the past decade.Only a few nontargeted dyes,including indocyanine green and methylene blue,are currently applied for fluorescence guided surgery in the clinic.While no targeted fluorescent probes have been approved for the clinic,a number of them have entered clinical trials.These probes have emission wavelengths in the visible and near infrared(NIR)-I(700-900 nm)range.Among them,activatable probes and nanoprobes have generated special interest.Compared with NIR-I fluorescent probes,NIR-II(1000-1700 nm)fluorescent probes exhibit better intravital performance in terms of increased penetration depths,reduced tissue autofluorescence,and higher signalto-background ratios.However,more challenges are expected before the successful translation of NIR-II probes from bench to bedside.This review provides a brief overview of targeted fluorescent probes under clinical evaluation and recent achievements in the field of NIR-II fluorescence imaging.In addition,we outline key considerations concerning the design of fluorescent probes for clinical translation.

术中荧光在神经肿瘤手术中的临床应用

荧光引导神经肿瘤切除是近年来的发展方向。肿瘤荧光剂的应用,改变了肿瘤神经外科的手术模式和理念。肿瘤荧光定位技术可以定位肿瘤、标记肿瘤边界,引导安全、最大限度地切除肿瘤,从而提高肿瘤全切率和神经血管保护率,延长无进展生存期。5-氨基乙酰丙酸(5-ALA)、荧光素钠(FLS)、吲哚菁绿(ICG)是神经肿瘤切除术中常用的荧光剂。5-ALA诱导荧光原卟啉IX的生存,引导肿瘤切除。尽管FLS不是肿瘤细胞特异性的荧光剂,但由于其安全性、有效性和使用方便的特点,已成为一种新的神经肿瘤替代荧光引导切除技术。ICG对血管性肿瘤,如血管母细胞瘤有很好的应用前景。本文主要针对荧光引导技术在神经肿瘤术中的应用作一综述,围绕荧光定位技术和临床应用等方面进行讨论,以期为临床提供参考。