ABSTRACT
Fluorescence-guided surgery (FGS) with tumor-targeted imaging agents, particularly those using the near-infrared wavelength, has emerged as a real-time technique to highlight the tumor location and margins during a surgical procedure. For accurate visualization of prostate cancer (PCa) boundary and lymphatic metastasis, we developed a new approach involving an efficient self-quenched near-infrared fluorescence probe, Cy-KUE-OA, with dual PCa-membrane affinity. Cy-KUE-OA specifically targeted the prostate-specific membrane antigen (PSMA), anchored into the phospholipids of the cell membrane of PCa cells and consequently showed a strong Cy7-de-quenching effect. This dual-membrane-targeting probe allowed us to detect PSMA-expressing PCa cells both in vitro and in vivo and enabled clear visualization of the tumor boundary during fluorescence-guided laparoscopic surgery in PCa mouse models. Furthermore, the high PCa preference of Cy-KUE-OA was confirmed on surgically resected patient specimens of healthy tissues, PCa, and lymph node metastases. Taken together, our results serve as a bridge between preclinical and clinical research in FGS of PCa and lay a solid foundation for further clinical research.
ABSTRACT
@#Nerve-specific fluorescent agents can be used as nerve markers in animals to guide surgical procedures and reduce the incidence of intraoperative nerve injury.In this study, the structure of oxazine mother nucleus was modified.A series of oxazine derivative fluorescent dyes YQN-3-YQN-6 were obtained by mass spectrometry and 1H NMR, which can highlight the peripheral nerve structure of rats.Among a series of targeted fluorescent dyes, YQN-3 had emission peaks near NIR and showed highly specific nerve targeting signals in the brachial plexus and sciatic nerves 4 h after intravenous administration.In addition, YQN-3 can accurately locate and identify recurrent laryngeal nerves during thyroidectomy, thus preserving the integrity of these nerves during surgery.With its simple synthesis and low toxicity, YQW-3 can be potentially applied for clinical neural tissue imaging.
ABSTRACT
STUDY DESIGN: A retrospective study. PURPOSE: We report our experience with 5-aminolevulinic acid (5-ALA)–assisted resection of spinal cord ependymomas in adults. OVERVIEW OF LITERATURE: Ependymoma is the most frequent primary spinal cord tumor in adults. Surgery is the treatment of choice in most cases. However, while complete resection is achieved in approximately 80% of cases, clinical improvement is achieved in 15% only. Five-ALA fluorescence–guided surgery seems to be useful for this tumor type. METHODS: We studied 14 patients undergoing 5-ALA fluorescence-guided surgery for spinal cord ependymomas in our service. The modified McCormick classification was used to determine clinical status and the degree of resection was assessed with magnetic resonance imaging. RESULTS: Of the 14 patients, the tumor showed an intense emission of fluorescence in 12 and the fluorescence was weak and nonuniform in two. Complete resection was achieved in 11 cases. According to the McCormick classification, 10 patients improved, two remained the same, and two deteriorated. CONCLUSIONS: Our results confirm that 5-ALA fluorescence-guided resection is useful in spinal cord ependymoma resection. Although the rate of complete resections is similar to that in published series without 5-ALA, clinical results are better when using 5-ALA with a lower percentage of clinical deterioration.
Subject(s)
Adult , Humans , Aminolevulinic Acid , Classification , Ependymoma , Fluorescence , Magnetic Resonance Imaging , Retrospective Studies , Spinal Cord Neoplasms , Spinal CordABSTRACT
The prognosis of glioma remains poor because of the infiltrative nature and the high local relapse rate.The current goals for patients with gliomas is maximal safe resection and adjuvant therapy.Tumor-specific photosensitizer,such as hematoporphyrin derivative (HpD) 5-aminolevulinic acid (5-ALA),can be selective up-taken and accumulated in tumor tissue.Light with appropriate wavelength can penetrate tumor tissue and excite the photosensitizer.The excited photosensitizer within glioma cells permits fluorescence visualization of tumor tissue during surgery and has been introduced in treatment of glioma as fluorescence-guided surgery (FGS).On the other hand,the toxicity of singlet oxygen generated by the excited photosensitizer has been used as photodynamic therapy (PDT) in selective destruction of the tumor.Some reports demonstrated the usefulness of adding PDT as an intraoperative adjuvant therapy,but the complexity associated with its implementation and the introduction of TMZ prevented PDT from becoming a routine therapy.However,FGS using 5-ALA in patients with malignant brain tumors has surfaced globally and may become a useful tool in increasing the extent of resection in gliomas.
ABSTRACT
Background: High grade gliomas (HGGs) are locally invasive brain tumours that carry a dismal prognosis. Although complete resection increases median survival, the difficulty in reliably demonstrating the tumour border intraoperatively is a norm. The Department of Neurosurgery, Hospital Sungai Buloh is the first public hospital in Malaysia to overcome this problem by adopting fluorescence-guided (FG) surgery using 5-aminolevulinic acid (5-ALA). Methods: A total of 74 patients with histologically proven HGGs treated between January 2008 and December 2014, who fulfilled the inclusion criteria, were enrolled. Kaplan-Meier survival estimates and Cox proportional hazard regression were used. Results: Significant longer survival time (months) was observed in the FG group compared with the conventional group (12 months versus 8 months, P 80 (P = 0.010), histology (P < 0.001), surgical method (P < 0.001) and adjuvant therapy (P < 0.001). Conclusion: This study showed a significant clinical benefit for HGG patients in terms of overall survival using FG surgery as it did not result in worsening of post-operative function outcome when compared with the conventional surgical method. We advocate a further multicentered, randomised controlled trial to support these findings before FG surgery can be implemented as a standard surgical adjunct in local practice for the benefit of HGG patients.
ABSTRACT
Extraventricular neurocytomas are rare brain tumors that have a diverse range of clinical characteristics. We describe two cases involving fluorescence-guided resection of extraventricular neurocytoma using 5-aminolevulinic acid (5-ALA) and evaluate the efficacy of the technique. We found that the tumor reactions to 5-ALA differed depending on the histologic grade. This finding shows that the 5-ALA fluorescence reaction may potentially be used as a biomarker of the clinical behavior of these tumors. To our knowledge, this is the first report in which fluorescence-guided resection was utilized for the resection of extraventricular neurocytomas.