5-ALA-Induced Fluorescence in Leptomeningeal Dissemination of Spinal Malignant Glioma

[Laser fluorescence spectroscopy and navigation in surgical treatment of spinal tumors: a systematic review]

The main problem in microsurgical resection of spinal cord tumors is excessive surgical aggression. The last one often leads to unsatisfactory clinical and neurological outcomes. Laser fluorescence spectroscopy is a modern neurosurgical approach to distinguish tumor boundaries even if standard visible fluorescence techniques are ineffective.

OBJECTIVE

To evaluate the effectiveness of laser fluorescence spectroscopy alone or in combination with visual 5-ALA fluorescence for improvement of safety and quality of resection, as well as intraoperative diagnosis.

MATERIAL AND METHODS

Searching for literature data was carried out in accordance with the PRISMA recommendations. The authors reviewed articles independently of each other. These data were systematized.

RESULTS

Laser fluorescence spectroscopy is valuable to identify fragments of intramedullary ependyomas in 86% of cases, while visual fluorescence only in 81% of cases. Advisability of this technique for low-grade astrocytomas is still unclear and requires further study. Its effectiveness is 87.5% for extramedullary meningiomas. Neuromas do not accumulate 5-ALA. In addition, this method can be used to determine the boundaries of intradural metastatic lesions.

CONCLUSION

5-ALA fluorescence is a safe and useful intraoperative method for identifying tumor tissue and resection margins in patients with intramedullary or infiltrative extramedullary spinal cord tumors. Visual fluorescence combined with laser spectroscopy is a perspective method for intraoperative visualization of tumor remnants. This approach can improve safety and postoperative outcomes while maintaining resection quality.

First Clinical Report of the Intraoperative Macro- and Micro-Photodiagnosis and Photodynamic Therapy Using Talaporfin Sodium for a Patient with Disseminated Lumbar Medulloblastoma

Photodiagnosis (PD) and photodynamic therapy (PDT) using the second-generation photosensitizer talaporfin sodium together with an exciting laser for primary intracranial malignant tumors is well recognized in Japan, and many medical institutions are introducing this new therapeutic option. In particular, intraoperative PDT using talaporfin sodium for infiltrating tumor cells in the cavity walls after the resection of malignant glioma is now covered by health insurance after receiving governmental approvement, and this method has been recommended in therapeutic guidelines for primary malignant brain tumors in Japan. On the other hand, experimental and clinical studies on the development of novel therapeutic strategies for malignant spinal cord tumors have not been reported to date, although their histological features are almost identical to those of intracranial malignant tumors. Therefore, the clinical outcomes of malignant spinal cord tumors have been less favorable than those of malignant brain tumors. In this report, we performed the PD and PDT using talaporfin sodium on a patient with a metastatic lumbar lesion that was detected on magnetic resonance image (MRI) 50 months after the resection of cerebellar medulloblastoma who presented with lumbago and sciatica. We were able to detect the target lesion in the conus medullaris using a surgical microscope, and detected the disseminated medulloblastoma cells floating in the cerebrospinal fluid using a compact fluorescence microscope. Furthermore, we performed PDT to the resected lumbar lesion with the adjuvant platinum-based chemotherapy, and the patient survived a meaningful life for more than 2 years after the lumbar surgery. This report describes the first case of a human patient in whom the efficacy of PD and PDT was demonstrated for a malignant spinal cord tumor.

Intrathecal methotrexate in combination with systemic chemotherapy in glioblastoma patients with leptomeningeal dissemination: A retrospective analysis

BACKGROUND

Glioblastoma (GBM) is one of the most common and aggressive primary malignant brain tumors with severe symptoms and a poor prognosis. Leptomeningeal dissemination (LMD) is a serious complication of GBM that often results in dire outcomes. There is currently no effective treatment.

AIM

To estimate the clinical outcomes of combination therapy in GBM patients with LMD

METHODS

A retrospective analysis was conducted using data collected from GBM patients diagnosed with LMD from January 2012 to December 2019 at our institution. All these patients had received at least one cycle of a combination therapy consisting of intrathecal methotrexate (MTX) and systemic chemotherapy. Clinical and pathological data were analyzed to explore the outcome of GBM patients with LMD and to determine the most effective treatment.

RESULTS

Twenty-six patients were enrolled in this study. The median time from GBM diagnosis to LMD development was 9.3 mo (range: 2-59 mo). The median overall survival of LMD patients from diagnosis to after receiving systemic chemotherapy in combination with intrathecal MTX was 10.5 mo (range: 2-59 mo). In the Cox univariate analysis, gross resection of tumor (P = 0.022), Karnofsky performance status (KPS) > 60 (P = 0.002), and Ommaya reservoir implant (P < 0.001) were correlated with survival. Multivariate analysis showed that KPS > 60 (P = 0.037) and Ommaya reservoir implant (P = 0.014) were positive factors correlated with survival. Myelotoxicity and gastrointestinal reactions were the common toxicities of this combination therapy. According to Common Terminology Criteria of Adverse Events 4.03, most of the patients presented with toxicity less than grade 3.

CONCLUSION

Intrathecal MTX administration combined with systemic chemotherapy is a potentially effective treatment for patients with GBM and LMD, with mild treatment-related side effects.

Fluorescein-guided surgery for intradural spinal tumors: A single-center experience

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Gross total removal has a pivotal role in surgical treatment of intradural spinal tumors.

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Sodium fluorescein prevents vascular injuries also preserving pial vessels in posterior myelotomy.

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Fluorescence before the durotomy helps to distinguishing tumor from healthy tissue in intradural lesions.

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Intraoperative fluorescence is safe and effective, also preserving functional anatomy in tumor removal.

Sodium Fluorescein for Spinal Intradural Tumors

Technological innovations in spinal intradural tumor surgery simplify treatment. Surgical treatment of cranial benign and malignant pathologies under microscope with sodium (Na)-fluorescein guidance has often been reported, but few studies have focused on spinal intradural tumors. We aimed to investigate the usefulness of Na-fluorescein under yellow filter in intradural spinal tumor surgery by retrospectively reviewing cases involving intramedullary and extramedullary tumors operated under the guidance of Na-fluorescein. Forty-nine adult patients with a diagnosis of spinal intradural tumor operated under a yellow filter (560 nm) microscope using Na-fluorescein dye were included in the study. Demographic data, such as age and sex, neurological status, extent of tumor resection, histopathological diagnosis, Na-fluorescein staining pattern, and its usefulness during surgery were noted and statistically analyzed. Of all recruited patients, 26 women (53.1%) and 23 men (46.9%), were included for analysis. The age range of the patients was 18–64 years, with a mean age of 41.6 ± 13.9. An intradural intramedullary mass was found in 30.6% (n = 15) of the patients, and an intradural extramedullary mass in 69.4% (n: 34). While Na-fluorescein staining was homogeneous in all intradural extramedullary tumors, 73.3% (n: 11) of intradural intramedullary tumors were homogeneous, and 13.3% (n: 2) moderately heterogeneous. In the whole study group, the Na-fluorescein staining pattern was helpful in surgical resection in 47 cases (95.9%). While 34/34 (100%) found it helpful for extramedullary tumors, 13/15 (86.7%) did in intramedullary tumors, and for 2/15 (13.3%) it was not. In conclusion, Na-fluorescein helps in distinguishing tumor from healthy tissue in intradural extramedullary and intramedullary tumor surgery under a yellow filter microscope in most cases, thus providing convenient assistance to surgeons.

Leptomeningeal Spread in Glioblastoma: Diagnostic and Therapeutic Challenges

BACKGROUND

Glioblastoma (GBM) is the most common and aggressive primary malignant brain tumor. Leptomeningeal spread (LMS) is a severe complication of GBM, raising diagnostic and therapeutic challenges in clinical routine.

METHODS

We performed a review of the literature focused on LMS in GBM. MEDLINE and EMBASE databases were queried from 1989 to 2019 for articles describing diagnosis and therapeutic options in GBM LMS, as well as risk factors and pathogenic mechanisms.

RESULTS

We retrieved 155 articles, including retrospective series, case reports, and early phase clinical trials, as well as preclinical studies. These articles confirmed that LMS in GBM remains (a) a diagnostic challenge with cytological proof of LMS obtained in only 35% of cases and (b) a therapeutic challenge with a median overall survival below 2 months with best supportive care alone. For patients faced with suggestive clinical symptoms, whole neuroaxis magnetic resonance imaging and cerebrospinal fluid analysis are both recommended. Liquid biopsies are under investigation and may help prompt a reliable diagnosis. Based on the literature, a multimodal and personalized therapeutic approach of LMS, including surgery, radiotherapy, systemic cytotoxic chemotherapy, and intrathecal chemotherapies, may provide benefits to selected patients. Interestingly, molecular targeted therapies appear promising in case of actionable molecular target and should be considered.

CONCLUSION

As the prognosis of glioblastoma is improving over time, LMS becomes a more common complication. Our review highlights the need for translational studies and clinical trials dedicated to this challenging condition in order to improve diagnostic and therapeutic strategies.

IMPLICATIONS FOR PRACTICE

This review summarizes the diagnostic tools and applied treatments for leptomeningeal spread, a complication of glioblastoma, as well as their outcomes. The importance of exhaustive molecular testing for molecular targeted therapies is discussed. New diagnostic and therapeutic strategies are outlined, and the need for translational studies and clinical trials dedicated to this challenging condition is highlighted.

Quantification of PpIX-fluorescence of cerebral metastases: a pilot study

5-ALA fluorescence-guided surgery (FGS) is a major advance in neuro-oncological surgery. So far, Protoporphyrin IX (PpIX)-fluorescence has been observed in about half of cerebral metastases resected with routinely equipped microscopes during 5-ALA FGS. The aim of the present pilot study was to quantify PpIX-induced fluorescence of cerebral metastases with a spectrometer. We hypothesize that non-fluorescing metastases under the operating microscope may have spectrometrically measurable levels of fluorescence. A second aim was to analyze correlations between quantified 5-ALA fluorescence and histology or primary tumor type, respectively. Standard FGS was performed in all patients. The fluorescence intensity of the metastasis was semi-quantitatively determined in vivo by a senior surgeon using a special surgical microscope equipped for FGS. A systematic spectrometric ex vivo evaluation of tumor specimens and PpIX-induced fluorescence was performed using a spectrometer connected by optic fibers to a handheld probe. Quantification of 5-ALA-derived fluorescence was measured in a standardized manner with direct contact between mini-spectrometer and metastasis. The difference between the maximum PpIX-fluorescence at 635 nm and the baseline fluorescence was defined as the PpIX fluorescence intensity of the metastasis and given in arbitrary units (AU). Diagnosis of a cerebral metastasis was confirmed by histopathological analysis. A total of 29 patients with cerebral metastases were included. According to neuropathological analysis, 11 patients suffered from non-small cell lung cancer, 10 patients from breast cancer, 6 patients from cancer originating in the gastro-intestinal tract, 1 patient suffered from a malignant melanoma and one patient from renal cancer. The mean age was 63 years (37-81 years). 15 patients were female, 14 patients male. 13 cerebral metastases were considered as ALA-positive by the surgeon. In nine metastases, 5-ALA fluorescence was not visible to the naked eye and could only be detected using the spectrometer. The threshold for an ALA signal rated as "positive" by the surgeon was PpIX fluorescence above 1.1 × 10⁶ AU. The mean PpIX fluorescence of all analyzed cerebral metastases was 1.29 × 10⁶ ± 0.23 × 10⁶ AU. After quantification, we observed a significant difference between the mean 5-ALA-derived fluorescence in NSCLC and breast cancer metastases (Mean Diff: - 1.2 × 10⁶; 95% CI of difference: - 2.2 × 10⁶ to - 0.15 × 10⁶; Šidák-adjusted p = 0.026). In our present pilot series, about half of cerebral metastases showed a 5-ALA fluorescence invisible to the naked eye. Over 50% of these non-fluorescent metastases show a residual 5-ALA fluorescence which can be detected and quantified using a spectrometer. Moreover, the quantified 5-ALA signal significantly differed with respect to the primary tumor of the corresponding cerebral metastasis. Further studies should evaluate the predictive value of the 5-ALA signal and if a quantified 5-ALA signal enables a reliable intraoperative differentiation between residual tumor tissue and edematous brain-in particular in metastases with a residual fluorescence signal invisible to the naked eye.

The role of 5-aminolevulinic acid in spinal tumor surgery: a review

Purpose

Primary intradural spinal neoplasms account for a small proportion of central nervous system tumors. The primary treatment for these tumors consists of maximal safe resection and preservation of neurologic function. Gross total resection, which is associated with the lowest rate of tumor recurrence and longer progression-free survival for most histologies, can be difficult to achieve. Currently, the use of 5-aminolevulinc acid (5-ALA) which takes advantage of Protoporphyrin IX (PpIX) fluorescence, is a well-established technique for improving resection of malignant cerebral gliomas. This technique is being increasingly applied to other cerebral neoplasms, and multiple studies have attempted to evaluate the utility of 5-ALA-aided resection of spinal neoplasms.

Methods

The authors reviewed the existing literature on the use of 5-ALA and PpIX fluorescence as an aid to resection of primary and secondary spinal neoplasms by searching the PUBMED and EMBASE database for records up to March 2018. Data was abstracted from all studies describing spinal neurosurgical uses in the English language.

Results

In the reviewed studies, the most useful fluorescence was observed in meningiomas, ependymomas, drop metastases from cerebral gliomas, and hemangiopericytomas of the spine, which is consistent with applications in cerebral neoplasms.

Conclusions

The available literature is significantly limited by a lack of standardized methods for measurement and quantification of 5-ALA fluorescence. The results of the reviewed studies should guide future development of rational trial protocols for the use of 5-ALA guided resection in spinal neoplasms.

Electronic supplementary material

The online version of this article (10.1007/s11060-018-03080-0) contains supplementary material, which is available to authorized users.