Objective: According to the World Health Organization, pancreatic endocrine tumors are graded by assessment of the Ki67 proliferation index and/or mitotic count. The objective was to find comparable grading on the basis of the novel mitotic marker phosphohistone-H3 (PHH3). Study Design: A computer-assisted system was used to assess 23 cell blocks stained with PHH3 and Ki67 antibodies. We investigated possible cut-points for PHH3 and computed percent agreement between the PHH3- and Ki67-based grading. Results: The Spearman correlation between percent Ki67 positive and percent PHH3 positive was 0.76 (p = 0.001). A value of 0.3% for the lower cut-point (‘cut-point 1', differentiating between grades 1 and 2) and values of about 1.8-1.9% for the higher cut-point (‘cut-point 2', differentiating between grades 2 and 3) shows optimal agreement between PHH3 and Ki67 grading. The percentage of positive cells was much higher for Ki67 than for PHH3 (mean 10.6 vs. 3.0%). Conclusions: PHH3 has good correlation with Ki67, but the range of PHH3 positivity is much narrower than that of Ki67 (range 0-4% for PHH3 vs. 0-50% for Ki67). Therefore, to be as accurate, grading on the basis of PHH3 requires evaluation of a larger number of tumor cells for a precise determination of percent PHH3-positive nuclei.

Copyright / Drug Dosage / Disclaimer
Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.
You do not currently have access to this content.