Brain Tumor Pathol DOI 10.1007/s10014-014-0201-5
LETTER TO THE EDITOR
Rapid cell cycle analysis for intraoperative diagnosis of brain tumors George Vartholomatos • George A. Alexiou • Anna Batistatou • Efstathios Lykoudis • Spyridon Voulgaris • Athanasios P. Kyritsis
Received: 25 July 2014 / Accepted: 23 September 2014 Ó The Japan Society of Brain Tumor Pathology 2014
Dear Editor, We read with great interest the recent article by Tanino et al. on the value of rapid immunohistochemistry (R-IHC) during brain tumor surgery. The authors developed a new immunohistochemistry method based on an alternating current electric field to facilitate the antigen–antibody reaction that could provide results for surgeons within 30 min [1]. The overall diagnostic accuracy of this method was 90.7 %. For the discrimination of low- and high-grade glioma, the authors evaluated supportive information of the Ki-67/MIB-1 index which could be completed within 16 min. Furthermore, in four cases of CNS lymphoma, CD20 and Ki-67/MIB-1 indices were successfully stained G. Vartholomatos Haematology Laboratory-Unit of Molecular Biology, University Hospital of Ioannina, 45500 Ioannina, Greece G. A. Alexiou S. Voulgaris Department of Neurosurgery, University Hospital of Ioannina, 45500 Ioannina, Greece G. A. Alexiou (&) A. P. Kyritsis Neurosurgical Institute, University of Ioannina School of Medicine, P.O. BOX 103, Neohoropoulo, 455 00 Ioannina, Greece e-mail: [email protected]; [email protected] A. Batistatou Department of Pathology, University Hospital of Ioannina, 45500 Ioannina, Greece E. Lykoudis Department of Plastic Surgery, University Hospital of Ioannina, 45500 Ioannina, Greece A. P. Kyritsis Department of Neurology, University Hospital of Ioannina, 45500 Ioannina, Greece
in all frozen samples using R-IHC. The authors concluded that R-IHC provides reliable results of IHC for CNS tumor diagnosis on frozen sections, and may contribute to an intraoperative rapid diagnosis [1]. Although flow cytometry has become a standard practice for the diagnosis, classification, staging and monitoring of patients with hematologic neoplasms, it has remained largely a research tool in solid tumors. Cell cycle analysis by flow cytometry can provide important information on tumor’s aggressiveness [2]. Furthermore, although flow cytometric analysis of DNA aneuploidy is not always associated with malignancy in several tumors, it is useful in brain tumors [3]. Recently, we have showed that based on G0/G1 and S-fraction we could differentiate low- from high-grade gliomas and benign from atypical/anaplastic meningiomas with high sensitivity and specificity (Fig. 1). In gliomas, a negative linear correlation between Ki-67 index and the G0/G1 fraction, and significant positive correlation between Ki-67 index and both S phase-fraction and mitoses were found. Apart from that, we have reported that cell cycle analysis has an additional prognostic significance. Glioma patients with G0/G1 value lower than 69 % and S phase value greater than 6 % were associated with worse survival [2]. The cell cycle analysis by flow cytometry usually requires 20 min. Recently, we developed a rapid cell cycle protocol that provides within 5 min intraoperative characterization of brain tumors and their margins [4]. The latter is of paramount importance to guide surgeon for tumor excision. Shioyama et al. also developed a rapid protocol for intraoperative characterization of resected gliomas by flow cytometry. By evaluating in 328 biopsy specimens the malignancy index, defined as the ratio of the number of cells with greater than normal DNA content to the total number of cells, Shioyama et al. [5] found significant differences between neoplastic and
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Fig. 1 a A case of a low grade astrocytoma tissue analyzed by flow cytometry. Ploidy histogram from the patient shows: G0/G1 = 77.3 % (M1), S = 1.3 % (M2), G2/M = 21.4 % (M3). b A case of primary central nervous system lymphoma. Ploidy histogram from the patient
shows: G0/G1 = 63.1 % (M1), S = 17.9 % (M2), G2/M = 23.5 % (M3). c A case of metastatic tumor. Ploidy histogram from the patient shows: G0/G1 = 23.5 % (M1), S = 14.2 % (M2), G2/M = 62.8 % (M3)
perilesional brain tissue. Cell cycle analysis has the advantage of being operated independently of pathology evaluation and can be interpreted easily. Nevertheless, contrary to immunohistochemistry which is widely available, flow cytometry can be performed only in limited numbers of institutes that have a flow cytometer. In conclusion, cell cycle analysis by flow cytometry is a promising adjunct for intraoperative brain tumor characterization and removal. The implementation of immunophenotyping analysis could provide analysis of specific tumor cell markers to further refine tumor diagnosis. Further studies are obviously needed that would also blindly compare flow cytometry and immunohistochemistry on frozen sections.
2. Alexiou GA, Vartholomatos G, Goussia A et al (2014) Fast cellcycle analysis for intraoperative characterization of brain tumor margins and malignancy. A Pilot study. J Clin Neurosci. doi:10. 1016/j.jocn.2014.05.029 3. El-Rayes BF, Norton CS, Sakr W et al (2005) Cellular DNA content parameters as prognostic indicators in human astrocytomas. J Neurooncol 71:85–89 4. Alexiou GA, Vartholomatos G, Goussia A et al (2013) DNA content is associated with malignancy of intracranial neoplasms. Clin Neurol Neurosurg 115:1784–1787 5. Shioyama T, Muragaki Y, Maruyama T et al (2013) Intraoperative flow cytometry analysis of glioma tissue for rapid determination of tumor presence and its histopathological grade: clinical article. J Neurosurg 118:1232–1238
References 1. Tanino M, Sasajima T, Nanjo H et al (2014) Rapid immunohistochemistry based on alternating current electric field for intraoperative diagnosis of brain tumors. Brain Tumor Pathol. doi:10. 1007/s10014-014-0188-y
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LETTER TO THE EDITOR
Rapid cell cycle analysis for intraoperative diagnosis of brain tumors George Vartholomatos • George A. Alexiou • Anna Batistatou • Efstathios Lykoudis • Spyridon Voulgaris • Athanasios P. Kyritsis
Received: 25 July 2014 / Accepted: 23 September 2014 Ó The Japan Society of Brain Tumor Pathology 2014
Dear Editor, We read with great interest the recent article by Tanino et al. on the value of rapid immunohistochemistry (R-IHC) during brain tumor surgery. The authors developed a new immunohistochemistry method based on an alternating current electric field to facilitate the antigen–antibody reaction that could provide results for surgeons within 30 min [1]. The overall diagnostic accuracy of this method was 90.7 %. For the discrimination of low- and high-grade glioma, the authors evaluated supportive information of the Ki-67/MIB-1 index which could be completed within 16 min. Furthermore, in four cases of CNS lymphoma, CD20 and Ki-67/MIB-1 indices were successfully stained G. Vartholomatos Haematology Laboratory-Unit of Molecular Biology, University Hospital of Ioannina, 45500 Ioannina, Greece G. A. Alexiou S. Voulgaris Department of Neurosurgery, University Hospital of Ioannina, 45500 Ioannina, Greece G. A. Alexiou (&) A. P. Kyritsis Neurosurgical Institute, University of Ioannina School of Medicine, P.O. BOX 103, Neohoropoulo, 455 00 Ioannina, Greece e-mail: [email protected]; [email protected] A. Batistatou Department of Pathology, University Hospital of Ioannina, 45500 Ioannina, Greece E. Lykoudis Department of Plastic Surgery, University Hospital of Ioannina, 45500 Ioannina, Greece A. P. Kyritsis Department of Neurology, University Hospital of Ioannina, 45500 Ioannina, Greece
in all frozen samples using R-IHC. The authors concluded that R-IHC provides reliable results of IHC for CNS tumor diagnosis on frozen sections, and may contribute to an intraoperative rapid diagnosis [1]. Although flow cytometry has become a standard practice for the diagnosis, classification, staging and monitoring of patients with hematologic neoplasms, it has remained largely a research tool in solid tumors. Cell cycle analysis by flow cytometry can provide important information on tumor’s aggressiveness [2]. Furthermore, although flow cytometric analysis of DNA aneuploidy is not always associated with malignancy in several tumors, it is useful in brain tumors [3]. Recently, we have showed that based on G0/G1 and S-fraction we could differentiate low- from high-grade gliomas and benign from atypical/anaplastic meningiomas with high sensitivity and specificity (Fig. 1). In gliomas, a negative linear correlation between Ki-67 index and the G0/G1 fraction, and significant positive correlation between Ki-67 index and both S phase-fraction and mitoses were found. Apart from that, we have reported that cell cycle analysis has an additional prognostic significance. Glioma patients with G0/G1 value lower than 69 % and S phase value greater than 6 % were associated with worse survival [2]. The cell cycle analysis by flow cytometry usually requires 20 min. Recently, we developed a rapid cell cycle protocol that provides within 5 min intraoperative characterization of brain tumors and their margins [4]. The latter is of paramount importance to guide surgeon for tumor excision. Shioyama et al. also developed a rapid protocol for intraoperative characterization of resected gliomas by flow cytometry. By evaluating in 328 biopsy specimens the malignancy index, defined as the ratio of the number of cells with greater than normal DNA content to the total number of cells, Shioyama et al. [5] found significant differences between neoplastic and
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Brain Tumor Pathol
Fig. 1 a A case of a low grade astrocytoma tissue analyzed by flow cytometry. Ploidy histogram from the patient shows: G0/G1 = 77.3 % (M1), S = 1.3 % (M2), G2/M = 21.4 % (M3). b A case of primary central nervous system lymphoma. Ploidy histogram from the patient
shows: G0/G1 = 63.1 % (M1), S = 17.9 % (M2), G2/M = 23.5 % (M3). c A case of metastatic tumor. Ploidy histogram from the patient shows: G0/G1 = 23.5 % (M1), S = 14.2 % (M2), G2/M = 62.8 % (M3)
perilesional brain tissue. Cell cycle analysis has the advantage of being operated independently of pathology evaluation and can be interpreted easily. Nevertheless, contrary to immunohistochemistry which is widely available, flow cytometry can be performed only in limited numbers of institutes that have a flow cytometer. In conclusion, cell cycle analysis by flow cytometry is a promising adjunct for intraoperative brain tumor characterization and removal. The implementation of immunophenotyping analysis could provide analysis of specific tumor cell markers to further refine tumor diagnosis. Further studies are obviously needed that would also blindly compare flow cytometry and immunohistochemistry on frozen sections.
2. Alexiou GA, Vartholomatos G, Goussia A et al (2014) Fast cellcycle analysis for intraoperative characterization of brain tumor margins and malignancy. A Pilot study. J Clin Neurosci. doi:10. 1016/j.jocn.2014.05.029 3. El-Rayes BF, Norton CS, Sakr W et al (2005) Cellular DNA content parameters as prognostic indicators in human astrocytomas. J Neurooncol 71:85–89 4. Alexiou GA, Vartholomatos G, Goussia A et al (2013) DNA content is associated with malignancy of intracranial neoplasms. Clin Neurol Neurosurg 115:1784–1787 5. Shioyama T, Muragaki Y, Maruyama T et al (2013) Intraoperative flow cytometry analysis of glioma tissue for rapid determination of tumor presence and its histopathological grade: clinical article. J Neurosurg 118:1232–1238
References 1. Tanino M, Sasajima T, Nanjo H et al (2014) Rapid immunohistochemistry based on alternating current electric field for intraoperative diagnosis of brain tumors. Brain Tumor Pathol. doi:10. 1007/s10014-014-0188-y
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