6
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: not found

      5-ALA–induced fluorescence as a marker for diagnostic tissue in stereotactic biopsies of intracranial lymphomas: experience in 41 patients

      Read this article at

      ScienceOpenPublisher
      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          OBJECTIVE

          Stereotactic needle biopsies are usually performed for histopathological confirmation of intracranial lymphomas to guide adequate treatment. During biopsy, intraoperative histopathology is an effective tool to avoid acquisition of nondiagnostic samples. In the last years, 5-aminolevulinic acid (5-ALA)–induced fluorescence has been increasingly used for visualization of diagnostic brain tumor tissue during stereotactic biopsies. Recently, visible fluorescence was reported in the first cases of intracranial lymphomas as well. The aim of this study is thus to investigate the technical and clinical utility of 5-ALA–induced fluorescence in a large series of stereotactic biopsies for intracranial lymphoma.

          METHODS

          This prospective study recruited adult patients who underwent frameless stereotactic needle biopsy for a radiologically suspected intracranial lymphoma after oral 5-ALA administration. During biopsy, samples from the tumor region were collected for histopathological analysis, and presence of fluorescence (strong, vague, or no fluorescence) was assessed with a modified neurosurgical microscope. In tumors with available biopsy samples from at least 2 different regions the intratumoral fluorescence homogeneity was additionally investigated. Furthermore, the influence of potential preoperative corticosteroid treatment or immunosuppression on fluorescence was analyzed. Histopathological tumor diagnosis was established and all collected biopsy samples were screened for diagnostic lymphoma tissue.

          RESULTS

          The final study cohort included 41 patients with intracranial lymphoma. Stereotactic biopsies with assistance of 5-ALA were technically feasible in all cases. Strong fluorescence was found as maximum level in 30 patients (75%), vague fluorescence in 2 patients (4%), and no visible fluorescence in 9 patients (21%). In 28 cases, samples were obtained from at least 2 different tumor regions; homogenous intratumoral fluorescence was found in 16 of those cases (57%) and inhomogeneous intratumoral fluorescence in 12 (43%). According to histopathological analysis, all samples with strong or vague fluorescence contained diagnostic lymphoma tissue, resulting in a positive predictive value of 100%. Analysis showed no influence of preoperative corticosteroids or immunosuppression on fluorescence.

          CONCLUSIONS

          The data obtained in this study demonstrate the technical and clinical utility of 5-ALA–induced fluorescence in stereotactic biopsies of intracranial lymphomas. Thus, 5-ALA can serve as a useful tool to select patients not requiring intraoperative histopathology, and its application should markedly reduce operation time and related costs in the future.

          Related collections

          Most cited references24

          • Record: found
          • Abstract: found
          • Article: not found

          Fluorescence-guided resection of glioblastoma multiforme by using 5-aminolevulinic acid-induced porphyrins: a prospective study in 52 consecutive patients.

          It has been established that 5-aminolevulinic acid (5-ALA) induces the accumulation of fluorescent porphyrins in glioblastoma multiforme (GBM), a phenomenon potentially exploitable to guide tumor resection. In this study the authors analyze the influence of fluorescence-guided resection on postoperative magnetic resonance (MR) imaging and survival in a series of patients who underwent surgery in the authors' department. Fifty-two consecutive patients with GBM received oral doses of 5-ALA (20 mg/kg body weight) 3 hours before induction of anesthesia. Intraoperatively, tumor fluorescence was visualized using a modified operating microscope. Fluorescing tissue was removed whenever it was considered safely possible. Residual enhancement on early postoperative MR imaging was quantified and related to each patient's characteristics to determine which factors influenced resection. Survival was analyzed using the Kaplan-Meier method and multivariate analysis was performed in which the Karnofsky Performance Scale (KPS) score, residual fluorescence, patient age, and residual enhancement on MR images were considered. Intraoperatively, two fluorescence qualities were perceived: solid fluorescence generally reflected coalescent tumor, whereas vague fluorescence mostly corresponded to infiltrative tumor. Complete resection of contrast-enhancing tumor was accomplished in 33 patients (63%). Residual intraoperative tissue fluorescence left unresected for safety reasons predicted residual enhancement on MR images in 18 of the 19 remaining patients. Age, residual solid fluorescence, and absence of contrast enhancement in MR imaging were independent explanatory factors for survival, whereas the KPS score was significant only in univariate analysis. No perioperative deaths and one case of permanent morbidity were encountered. The observations in this study indicate the usefulness of 5-ALA-induced tumor fluorescence for guiding tumor resection. The completeness of resection, as determined intraoperatively from residual tissue fluorescence, was related to postoperative MR imaging findings and to survival in patients suffering from GBM.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Coregistered fluorescence-enhanced tumor resection of malignant glioma: relationships between δ-aminolevulinic acid-induced protoporphyrin IX fluorescence, magnetic resonance imaging enhancement, and neuropathological parameters. Clinical article.

            The aim of this study was to investigate the relationships between intraoperative fluorescence, features on MR imaging, and neuropathological parameters in 11 cases of newly diagnosed glioblastoma multiforme (GBM) treated using protoporphyrin IX (PpIX) fluorescence-guided resection. In 11 patients with a newly diagnosed GBM, δ-aminolevulinic acid (ALA) was administered to enhance endogenous synthesis of the fluorophore PpIX. The patients then underwent fluorescence-guided resection, coregistered with conventional neuronavigational image guidance. Biopsy specimens were collected at different times during surgery and assigned a fluorescence level of 0-3 (0, no fluorescence; 1, low fluorescence; 2, moderate fluorescence; or 3, high fluorescence). Contrast enhancement on MR imaging was quantified using two image metrics: 1) Gd-enhanced signal intensity (GdE) on T1-weighted subtraction MR image volumes, and 2) normalized contrast ratios (nCRs) in T1-weighted, postGd-injection MR image volumes for each biopsy specimen, using the biopsy-specific image-space coordinate transformation provided by the navigation system. Subsequently, each GdE and nCR value was grouped into one of two fluorescence categories, defined by its corresponding biopsy specimen fluorescence assessment as negative fluorescence (fluorescence level 0) or positive fluorescence (fluorescence level 1, 2, or 3). A single neuropathologist analyzed the H & E-stained tissue slides of each biopsy specimen and measured three neuropathological parameters: 1) histopathological score (0-IV); 2) tumor burden score (0-III); and 3) necrotic burden score (0-III). Mixed-model analyses with random effects for individuals show a highly statistically significant difference between fluorescing and nonfluorescing tissue in GdE (mean difference 8.33, p = 0.018) and nCRs (mean difference 5.15, p < 0.001). An analysis of association demonstrated a significant relationship between the levels of intraoperative fluorescence and histopathological score (χ(2) = 58.8, p < 0.001), between fluorescence levels and tumor burden (χ(2) = 42.7, p < 0.001), and between fluorescence levels and necrotic burden (χ(2) = 30.9, p < 0.001). The corresponding Spearman rank correlation coefficients were 0.51 (p < 0.001) for fluorescence and histopathological score, and 0.49 (p < 0.001) for fluorescence and tumor burden, suggesting a strongly positive relationship for each of these variables. These results demonstrate a significant relationship between contrast enhancement on preoperative MR imaging and observable intraoperative PpIX fluorescence. The finding that preoperative MR image signatures are predictive of intraoperative PpIX fluorescence is of practical importance for identifying candidates for the procedure. Furthermore, this study provides evidence that a strong relationship exists between tumor aggressiveness and the degree of tissue fluorescence that is observable intraoperatively, and that observable fluorescence has an excellent positive predictive value but a low negative predictive value.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Quantitative fluorescence in intracranial tumor: implications for ALA-induced PpIX as an intraoperative biomarker.

              Accurate discrimination between tumor and normal tissue is crucial for optimal tumor resection. Qualitative fluorescence of protoporphyrin IX (PpIX), synthesized endogenously following δ-aminolevulinic acid (ALA) administration, has been used for this purpose in high-grade glioma (HGG). The authors show that diagnostically significant but visually imperceptible concentrations of PpIX can be quantitatively measured in vivo and used to discriminate normal from neoplastic brain tissue across a range of tumor histologies. The authors studied 14 patients with diagnoses of low-grade glioma (LGG), HGG, meningioma, and metastasis under an institutional review board-approved protocol for fluorescence-guided resection. The primary aim of the study was to compare the diagnostic capabilities of a highly sensitive, spectrally resolved quantitative fluorescence approach to conventional fluorescence imaging for detection of neoplastic tissue in vivo. A significant difference in the quantitative measurements of PpIX concentration occurred in all tumor groups compared with normal brain tissue. Receiver operating characteristic (ROC) curve analysis of PpIX concentration as a diagnostic variable for detection of neoplastic tissue yielded a classification efficiency of 87% (AUC = 0.95, specificity = 92%, sensitivity = 84%) compared with 66% (AUC = 0.73, specificity = 100%, sensitivity = 47%) for conventional fluorescence imaging (p < 0.0001). More than 81% (57 of 70) of the quantitative fluorescence measurements that were below the threshold of the surgeon's visual perception were classified correctly in an analysis of all tumors. These findings are clinically profound because they demonstrate that ALA-induced PpIX is a targeting biomarker for a variety of intracranial tumors beyond HGGs. This study is the first to measure quantitative ALA-induced PpIX concentrations in vivo, and the results have broad implications for guidance during resection of intracranial tumors.
                Bookmark

                Author and article information

                Journal
                Neurosurgical Focus
                Journal of Neurosurgery Publishing Group (JNSPG)
                1092-0684
                June 2018
                June 2018
                : 44
                : 6
                : E7
                Affiliations
                [1 ]1Department of Neurosurgery,
                [2 ]2Institute of Neurology,
                [3 ]5Comprehensive Cancer Center–Central Nervous System Tumours Unit, Medical University Vienna, Austria
                [4 ]3Department of Biomedical Imaging and Image-Guided Therapy,
                [5 ]4Department of Internal Medicine I, and
                Article
                10.3171/2018.3.FOCUS1859
                d6e393d0-1202-4b16-92ff-9cabbd7eac7a
                © 2018
                History

                Comments

                Comment on this article