Article

Useof anti-phosphohistone H3 immunohistochemistry to determine mitotic rate in thin melanoma.

Department of Dermatology, University of South Florida, Tampa, FL, USA.
The American Journal of dermatopathology (Impact Factor: 1.43). 10/2010; 32(7):650-4. DOI: 10.1097/DAD.0b013e3181cf7cc1
Source: PubMed

ABSTRACT The seventh edition of the American Joint Committee on Cancer (AJCC) melanoma staging system, slated for release in 2010, will introduce mitotic rate (MR) as one of the primary criteria for staging thin melanoma (< or = 1.0 mm). Accurate counts are essential because the finding of a single mitotic figure (MF) will alter the staging and management of these patients. The traditional manner of counting of mitotic figures (MFs) using a X40 objective is time consuming and prone to inter- and intraobserver variability. We employed an antibody to phosphohistone H3 (pHH3, ser10) that labels MFs in all stages of mitosis, to evaluate mitotic counts at X20 in tissue sections from 30 melanoma patients with thin lesions 0.45 to 1.2 mm in depth, and compared results with routine hematoxylin and eosin (H&E) in a double-blind fashion. The mean MR was 1.63 by antipHH3, and 0.67 for H&E, representing a mean increase of 243%. The Spearman correlation coefficient for MR in H&E and anti-pHH3 sections was 0.88 (P < 0.0001). When melanomas were designated as "mitotically active," if the MR by anti-pHH3 was > or = 2 and > or = 1 by H&E, the correlation coefficient increased to 1.0. No thin melanomas were mitotically inactive on anti-pHH3 but active on H&E. Results indicate that anti-pHH3 is a useful immunostain for labeling melanocytes in mitosis. Subsequent studies will be needed confirm the accuracy of this staining technique, which has the potential to be used as a screening method for counting MFs before conventional H&E methodology in the microstaging of thin melanoma.

0 Followers
 · 
107 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: Context .- Immunohistochemistry is not a diagnostic test but a highly valuable tool that requires interpretation within a context. Objective .- To review the current status and limitations of immunohistochemistry in dermatopathology. Data Sources .- English-language literature published between 1980 and 2014. Conclusions .- Although immunohistochemistry is rarely completely specific or sensitive, it is an important adjunctive technique in dermatopathology and can be helpful in a series of diagnostic dilemmas.
    Archives of pathology & laboratory medicine 01/2015; 139(1):83-105. DOI:10.5858/arpa.2014-0075-RA · 2.88 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: T1 melanoma staging is significantly affected by tissue sampling approaches, which have not been well characterized.
    Journal of the American Academy of Dermatology 09/2014; DOI:10.1016/j.jaad.2014.07.056 · 5.00 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: While World Health Organization (WHO) grading of meningioma stratifies patients according to recurrence risk overall, there is substantial within-grade heterogeneity with respect to recurrence-free survival (RFS). Most meningiomas are graded according to mitotic counts per unit area on H&E sections, a method potentially confounded by tumor cellularity, as well as potential limitations of accurate mitotic figure detection on routine histology. To refine mitotic figure assessment we evaluated 363 meningiomas with phospho-histoneH3(Ser10), and determined the mitotic index (number of mitoses per 1000 tumor cells). The median mitotic indices among WHO grades I (n=268), II (n=84), and III (n=11) tumors were 1, 4, and 12, Classification and regression tree analysis to categorize cutoffs identified 3 subgroups defined by mitotic indices of 0-2, 3-4, and ≥5, which on univariate analysis were associated with RFS (p<0.01). In multivariate analysis, mitotic index subgrouped in this manner was significantly associated with RFS (p<0.01) after adjustment for Simpson grade, WHO grade, and MIB-1 index. Mitotic index was then examined within individual WHO grade, showing that for grade I and II meningiomas, mitotic index can add additional information to RFS risk. The results suggest that the use of a robust mitotic marker in meningioma could refine risk stratification.
    Brain Pathology 07/2014; 25(3). DOI:10.1111/bpa.12174 · 4.35 Impact Factor