1. UTILITY OF BONE MARROW ASPIRATION AND BIOPSY (BMAB) IN INITIAL STAGING OF EWING SARCOMA (EWS)
Lisa M. Kopp, Winston W. Huh, Cynthia E. Herzog, Chengcheng Hu, Andrea White-Collins, Beatriz Rozo, Angela Yarborough, Pooja Hingorani

2. Background
Pediatric and adolescents patients with newly diagnosed Ewing Sarcoma (EWS) have a bilateral bone marrow aspiration and biopsy (BMAB) performed as part of the initial staging evaluation
BMAB is a painful procedure that is performed using general anesthesia
Stressful for newly dx patients and can have complications

3. Background
The NCCN guidelines on bone cancer recommend the option of either a BMAB or MRI of the spine and pelvis in newly diagnosed adult patients
The necessity of a BMAB in staging pediatric and adolescent EWS patients in addition to radiological evaluation has not been previously established

4. Objectives
To evaluate the association between imaging determined non-metastatic EWS and BM metastasis in pediatric and adolescent patients
To evaluate the association between BM metastasis and other clinical characteristics of pediatric and adolescent EWS patients

5. Methods Retrospective review involving 3 institutions
Eligibility: Patients less than 40 years of age with newly diagnosed EWS between the years ; available initial staging scans and BM evaluation
116 patients
Initial staging reviewed
Imaging (MRI primary site, CT chest, Bone scan)
Bone Marrow Aspiration and Biopsy

6. Patient Characteristics
Non-metastatic (n=85)
Metastatic (n=31)
Gender
Male
Female
47 (55.3%)
38 (44.7%)
18 (58.1%)
13 (41.9%)
Age at Diagnosis*
13 (1, 38)
16 (3, 25)
Primary Tumor Site
Pelvis
Non-pelvis
15 (17.6%)
70 (82.4%)
14 (45.2%)
17 (54.8%)
Primary Tumor Size (cm)*, **
7.5 (1.3, 26.0)
11.2 (3.5, 35.0)
* Median (range)
** Primary tumor size of metastatic patients was significantly higher that that of non-metastatic patients (p-value = by Wilcoxon rank-sum test)

7. Metastatic Patients Metastatic site:
Patients with multiple metastatic sites:
Lung alone
Bone alone
BM alone
Multiple
13 (41.9%)
2 (6.5%)
0 (0.0%)
16 (51.6%)
Lung
Bone BM
Lymph Nodes
9 (56.3%)
14 (87.5%)
13 (81.3%)
2 (12.5%)

8. BMAB Results
None of the 85 non-metastatic patients determined by imaging had positive BMAB
A positive pelvic primary site was not correlated with a positive bone marrow
BMAB Correlation with pelvic primary site (n=116)
Pelvic
Non-Pelvic
P-value
BMAB positive 6 7
0.087
BMAB negative 23 80

9. Number of Bony Metastatic Sites (bone scan, n=28)
BMAB Results
13 of 31 metastatic patients by imaging had positive BMAB
Number of Bony Metastatic Sites (bone scan, n=28)
BMAB positive
BMAB negative
P-value
3.5 (1.0, 11.0)
0.0 (0.0, 2.0)
<
None of the 85 non-metastatic patients as determined by imaging
The number of boney mets by bone scan was missing for 3 of the patients – n =28
# bony sites per person for the 28 people – BMAB Median 3.5 bony sites(range). BMAB neg median bony mets – being BMAB positive more likely bony sites

10. Association of Metastasis by Imaging and BMAB
BMAB Results
Bone Metastasis
Lung Metastasis
Yes No
Positive 12 1 6 7
Negative 4 14 16 2
P-value for association*
0.0002
0.017
*Fisher’s exact test was used to evaluate association.
It appears that having bone metastasis positive correlation to have bone metastasis
Having lung mets had a neg correlation with positive bone marrow aspiration biopys

11. Conclusion
Pediatric and adolescent Ewing sarcoma patients with non-metastatic disease by imaging may have a bone marrow aspiration and biopsy eliminated as part of initial staging
In patients with metastatic disease there is a high correlation between bone marrow metastasis and the number of bony metastatic sites

12. Acknowledgments University of Arizona Winston W. Huh, MD
University of Texas
MD Anderson Cancer Center Children’s Cancer Hospital
Phoenix Children’s Hospital
Pooja Hingorani, MD
Andrea White-Collins, NP
University of Arizona – Mel and Enid Zuckerman College of Public Health
Chengcheng Hu, PhD
Winston W. Huh, MD
Cynthia E. Herzog, MD, MPH
Beatriz Rozo, NP
Angela Yarbarough, NP