Immunohistochemical detection of promyelocytic leukemia zinc finger and histone 1.5 in uterine leiomyosarcoma and leiomyoma.
OBJECTIVE
The accurate distinction of leiomyoma from leiomyosarcoma is essential for patient management. However, the distinction can be difficult to make, particularly in tissue biopsy samples. Immunohistochemistry has been established as a useful technique to aid in the diagnosis of malignancies. The advantages of immunohistochemical studies are their ease of use and interpretation. This study is the first to evaluate the utility of the promyelocytic leukemia zinc finger (PLZF) protein and the histone 1.5 (H1.5) protein as potential diagnostic immunohistochemical markers for distinguishing leiomyosarcoma from leiomyoma.


METHODS
Tissue samples from 21 leiomyosarcomas and 26 leiomyomas were studied. The student t-test and the Fisher exact test were used to calculate the differences in staining between the 2 groups.


RESULTS
Statistically significant differences were found in the staining indices of anti-PLZF and anti-H1.5 when comparing benign and malignant tumors (P < .0001 and P < .0001, respectively). The mean H1.5 staining score in leiomyosarcomas was 158.3, compared to 28.3 in leiomyomas. The mean PLZF score in leiomyosarcomas was 1.5 in contrast to 71.5 in leiomyomas. For H1.5 at a score ≥60, the sensitivity and specificity were 90.5% and 84.6%, respectively. For PLZF, a score ≤15 had a test sensitivity and specificity of 100% and 80.8%, respectively. This suggests that staining for H1.5 or PLZF can serve as a good screening test. Additionally, combining the 2 immunostains results in a sensitivity and specificity of 90.5% and 97.5%, respectively, in differentiating between leiomyoma and leiomyosarcoma.


CONCLUSIONS
We describe immunostaining for PLZF and H1.5 in benign and malignant uterine smooth muscle tumors. Statistically significant differences in staining patterns were found, suggesting utility in distinguishing leiomyosarcomas from leiomyomas.
Department of Obstetrics, Division of Gynecologic Oncology, Gynecology and Reproductive Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA mazdak_mom@yahoo.com.
Mazdak
M
Momeni
Department of Pathology, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
Tamara
T
Kalir
Department of Obstetrics, Division of Gynecologic Oncology, Gynecology and Reproductive Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
Sara
S
Farag
Department of Pathology, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
Yayoi
Y
Kinoshita
Department of Pathology, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
Taisha Y
TY
Roman
Department of Obstetrics, Division of Gynecologic Oncology, Gynecology and Reproductive Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
Linus
L
Chuang
Department of Obstetrics, Division of Gynecologic Oncology, Gynecology and Reproductive Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
David A
DA
Fishman
Department of Pathology, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
David E
DE
Burstein
D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis; D005260:Female; D006657:Histones / Q000032:analysis*; D006801:Humans; D051741:Kruppel-Like Transcription Factors / Q000032:analysis*; D007889:Leiomyoma / Q000473:pathology*; D007890:Leiomyosarcoma / Q000473:pathology*; D008875:Middle Aged; D000075722:Promyelocytic Leukemia Zinc Finger Protein; D014594:Uterine Neoplasms / Q000473:pathology*; D016335:Zinc Fingers / Q000502:physiology*
D014408:Biomarkers, Tumor; C104345:H1-5 protein, human; D006657:Histones; D051741:Kruppel-Like Transcription Factors; D000075722:Promyelocytic Leukemia Zinc Finger Protein; C092037:ZBTB16 protein, human
histone H1.5 protein; leiomyoma; leiomyosarcoma; promyelocytic leukemia zinc finger (PLZF) protein