SPECIAL DEPARTMENTS
Authors: Howard M. Katzenstein, Susan L. Cohn, Susan Crawford, Dafna Meitar, Adela Cañete, Victoria Castel, Samuel Navarro
Journal: Journal of Clinical Oncology (2000)

Article Tools SPECIAL DEPARTMENTS Article Tools OPTIONS & TOOLS Export Citation Track Citation Add To Favorites Rights & Permissions COMPANION ARTICLES No companion articles ARTICLE CITATION DOI: 10.1200/JCO.2000.18.14.2789 Journal of Clinical Oncology - published online before print September 21, 2016 PMID: 10894881 Howard M. KatzensteinxHoward M. KatzensteinSearch for articles by this author , Susan L. CohnxSusan L. CohnSearch for articles by this author , Susan CrawfordxSusan CrawfordSearch for articles by this author , Dafna MeitarxDafna MeitarSearch for articles by this author Adela CañetexAdela CañeteSearch for articles by this author , Victoria CastelxVictoria CastelSearch for articles by this author , Samuel NavarroxSamuel NavarroSearch for articles by this author Show More Children’s Memorial Hospital Northwestern University School of Medicine ChicagoILPediatric Hematology-Oncology Department The Chaim Sheba Medical Center Tel-HashomerIsraelHospital Infantil La Fe ValenciaSpainUniversidad de Valencia ValenciaSpain https://doi.org/10.1200/JCO.2000.18.14.2789 First Page Full Text PDF Figures and Tables © 2000 by American Society of Clinical OncologyjcoJ Clin OncolJournal of Clinical OncologyJCO0732-183X1527-7755American Society of Clinical OncologyResponse14072000In Reply:We are thankful for the opportunity to comment on the letter from Katzenstein et al regarding our study about vascular parameters in a cohort of neuroblastoma patients.1 When the study by Meitar et al2 was published in the Journal of Clinical Oncology in 1996, we were very interested in analyzing our patients with a more objective and reproducible method than the one proposed by these authors. At that time, the methodology to study vascular parameters in breast carcinomas by means of computerized methods was fully established and developed in our department of pathology. Indeed, that methodology followed the recommendations given by the consensus of experts,3 from which Katzenstein et al extracted only one sentence for their comment. Besides, this methodology has been published elsewhere.4Cohorts of 50 or 66 patients in retrospective studies, as in these two, are not representative of neuroblastoma. In our case, the 66 patients did not statistically differ from the large cohort of Spanish patients. We have already communicated5 the favorable characteristics of Spanish neuroblastoma patients in the N-II-92 protocol. Although retrospective, it had the advantage that all patients were treated according to one protocol; therefore, differences in outcome would be due to tumoral behavior, abolishing the differences that could appear due to different therapeutic strategies over the years. From our study, we did not make conclusions about the prognostic impact of angiogenesis in neuroblastoma; however, in our group of patients, the prognostic impact of angiogenesis was not as crucial as we expected. We observed some differences in vascular parameters in relapses, but they were not statistically significant. We believe this important question can only be addressed in larger multicentric supranational studies, as it has been done for MYCN, 1p deletion, or other prognostic factors in neuroblastoma.It is well known that neuroblastoma is a very complex and heterogeneous tumor from the pathologist’s point of view,6 with tumoral and stromal areas of very different appearance and behavior in the same slide. Vascular hot spots are the critical regions to assess accurately the association between tumor progression and the angiogenic potential; choosing them is the most critical point, and the training and experience of the investigator is very important. Pilot studies7 have suggested that the degree of subjectivity related to the hot spot selection step is acceptable. In our case, vascular hot spots were encountered predominantly at the peripheral tumor margin, at low magnification, with a low background staining and a highly specific and intense labeling of endothelial cells (anti-CD34, microwave antigen retrieval, and protease pretreatment). Indeed, three (4%) of 69 initial patients had to be excluded. That small percentage is due to the previous development and validation of the methodology at our laboratory.4 Although Weidner et al8,9 have suggested a field size of 0.74 mm2, a wide range has been used, from 0.12 to 1.74 mm2. The range of vessel number in our study varied between nine and 1,034, with the frequencies shown in Fig 1. Again, different studies2,8-10 have used methodologies that are different from ours and are not comparable. Fig. 1. Hystogram of microvessel number in 66 samples analyzed.Because of the pathologic complexity of neuroblastoma, it is not known whether the vasculature patterns in this tumor are similar to those of carcinomas or sarcomas. It could be that different vascular patterns in neuroblastoma exist, related perhaps to biologic aspects (more differentiated v undifferentiated) or location (abdominal v thoracic), as has been described for primitive neuroectodermal tumors,11 which are closer to neuroblastoma than sarcomas. A better and deeper knowledge of vasculature patterns in neuroblastoma is needed so that scientists can choose the right methodology for studying the prognostic impact of angiogenesis in neuroblastoma.From our point of view, the main disadvantages of our methodology are as follows: first, it is time-consuming, and second, it requires sophisticated equipment that might not be available for all laboratories. In that sense, the methodology used by Meitar et al2 is more appealing and would be useful for our daily practice if it followed the consensus recommendations.3 As proposed before, any methodology used to assess angiogenesis in neuroblastoma should be validated in larger prospective supranational studies.4. Cañete A, Navarro S, Bermúdez J, et al: Angiogenesis in neuroblastoma: Relationship to survival and other prognostic factors in a cohort of neuroblastoma patients. J Clin Oncol 18::27,2000-34, Link, Google Scholar4. Meitar D, Crawford SE, Rademaker A, et al: Tumor angiogenesis correlates with metastatic disease, N- amplification and poor outcome in human neuroblastoma. J Clin Oncol 14::405,1996-414, myc Link, Google Scholar4. Vermeulen PB, Gasparini G, Fox SB, et al: Quantification of angiogenesis in solid human tumors: An international consensus on the methodology and criteria evaluation. Eur J Cancer 32A::2472,1996-2484, Google Scholar4. Sales A, Ruiz A, Llombart-Bosch Comparative morphometric evaluation of microvessel density and nuclear area in ductal carcinoma in situ and hyperplastic ductal breast lesions. Breast 8::21,1999-25, Crossref, Google Scholar4. Castel V, Cañete A, García-Miguel P, et al: Changes in age and stage distribution of neuroblastoma patients in Spain: 4th International Symposium on Neuroblastoma Screening. Stutgart, Germany, November 9-11, 1995 Google Scholar4. Shimada H, Ambros MI, Dehner LP, et al: The International Neuroblastoma Pathology Classification (The Shimada System). Cancer 86::364,1999-372, Crossref, Medline, Google Scholar4. Simpson JF, Ahn C, Battifora H, et al: Endothelial area as a prognostic indicator for invasive breast carcinoma. Cancer 77::2077,1996-2085, Crossref, Medline, Google Scholar4. Weidner N, Semple J, Welch WR, et al: Tumor angiogenesis and metastasis: Correlation in invasive breast carcinoma. N Engl J Med 324::1,1991-8, Crossref, Medline, Google Scholar4. Weidner N, Carroll PR, Flax J, et al: Tumor angiogenesis correlates with metastasis in invasive prostate carcinoma. Am J Pathol 143::401,1993-409, Medline, Google Scholar4. Horak ER, Leek R, Klenk N, et al: Angiogenesis, assessed by platelet/endothelial cell adhesion molecule antibodies, as indicator of node metastases and survival in breast cancer. Lancet 340::1120,1992-1124, Crossref, Medline, Google Scholar4. Goldbrunner RH, Pietsch T, Vince GH, et al: Different vascular patterns of medulloblastoma and supratentorial primitive neuroectodermal tumors. Int J Dev Neurosci 17::593,1999-599, Crossref, Medline, Google Scholar