1. Abbas Agaimy, MD Erlangen, Germany
The 10th Arkadi M. Rywlin International Pathology Slide Seminar Symposium in Anatomic Pathology, May 21 – 23, 2018 Split, Croatia
CASE #34
Abbas Agaimy, MD Erlangen, Germany

2. Objectives of this case
Recognize a distinctive tumor type (birth of a new entity!).
Appreciate its association with a hereditary disease.

3. AMR Case #34 Caucasian male. Multiple lipomas excised at age 26 y.
(Neck, trunk & upper arm).
Then again at age 34 from similar sites.
At age 35: bilateral scrotal masses (submited slides).
No other special history submitted.

4. Bilateral scrotal tumors
(courtesy of Dr. W. Schaschkow, Gelsenkirchen, Germany)

5. At low power, well circumscribed with striking size variation
of adipocytes

6. Striking fat cell size variation (anisocytosis) but little atypia

7. Degenerative changes (variable staining of cell borders

8. Grape-like atypical vacuolation
S100

9. Chicken-wire phenomenon of cell borders/periphery

10. Mild atypia & vacuolated nuclei (Lochkerne)

11. Mild atypia & vacuolated nuclei (Lochkerne) are typical

12. Ruptured single fat cells with
histiocytes encasing them

13. Rb1 lost in most of fatty
& stromal cells

14. Other markers tested CD34: pos in scattered stromal cells
MDM2&CDK4 IHC: neg
MDM2&CDK4 FISH: neg for amplification
Rb1 FISH: no abnormality detected in this tumor

15. What is your diagnosis?

16. Our case
ordinary lipoma

17. Our case
conventional ALT

18. Our case
pleomorphic/SCL

19. What is your diagnosis? Not an ordinary lipoma.
Not a conventional ALT.
No classical spindle cell lipoma component.
????

20. USCAP 2015 (Boston)

24. On the occasion of his scrotal lipomas, it came out that this
patient had a retinoblastoma at age 1.

25. Male.
Multiple lipomas excised at age 26 y.
(Neck, trunk & upper arm).
Then again at age 34 from similar sites.
At age 35: bilateral scrotal masses (submited slides).
Striking concordance
between the two cases

26. M: F = 7:1
Age (M: 51 y)
Site: mainly upper back, shoulders or posterior neck
15% multiple (2 to 5 tumors)
Rb1 loss by ICH: 69% cases.
>23% Rb1 deletions by FISH
Local rec: 16%.

27. TP53

28. Take-home-message
Dysplastic (anisometric cell) lipoma is a frequent but likely misnamed subcutaneous fatty neoplasm.
Distinctive from conventional ALT histolgically and by IHC.
Distinctive from conventional pleomorphic/spindle cell lipoma.
Has a recurrence rate in the range of 16%.
No dedifferentiation reported.
Tends to be frequently multifocal.
Associated with childhood retinoblastoma in a subset of cases.

29. 29 Kilometer apart
City of Berber
Sudan

30. Thank you for your attention
29 Kilometer apart
City of Atbara
Kamal G. Ishak
( )
City of Berber
Sudan