Skeletal and Extra Skeletal Ewing’s Sarcoma / Primitive Neuroectodermal Tumors(PNET): Clinicopathological Study

Abstract

Background: To analyze the characteristics of
skeletal and extra skeletal Ewing’s sarcoma /
Primitive Neuroectodermal Tumors PNET .
Methods: In this descriptive cross-sectional study
cases of skeletal and extra skeletal PNET were
analyzed. Age, gender, site of biopsy, and results of
Immunohistochemistry were recorded.
Results: Out of 80 cases, 65.4 % were males . The
age ranged from 1 to 45 years, with the mean age of
18 years. Most frequent age group was the second
decade of life(54 %). There were 37 cases of Skeletal
Ewing Sarcoma and 43 cases of Extra skeletal PNET.
Among the 37 ( 47 % ) cases of Ewing sarcoma of
bone, femur (21.62%) was the commonest. Out of the
43 cases of Extra skeletal PNET, 41 had peripheral
PNET while 2 had CNS PNET. In the 41 patients of
Primitive PNET, head and neck (18.6%) and chest
(Askin Tumor) (16.27%) were the commonest. CD 99
was positive in 73 %, while, NSE, and Cytokeratin
were positive in 32%. Periodic Acid Schiff was
positive in 53 cases.
Conclusion: Extra skeletal (53.75%) involvement
comprises a larger number of cases as compared to
skeletal Ewing’s sarcoma. Majority of the cases
present in the second decade of life. In skeletal
Ewing’s Sarcoma, femur is the commonest involved
site. Head and neck and chest are the commonest in
extraskeletal. In extraskeletal a propensity of the soft
tissue around leg is also observed