Case 11/2011

B. LachDepartment of Pathology and Molecular

Medicine, McMaster University, Hamilton, Ont.

CANADA

Abbreviations used: B-brain, M-meningioma, SMA smooth muscle actin,SA-sarcoma, EMA – epithelial membrane antigen

76yo, history of multiple myelomaLytic bone lesionMRI: intracranial/extracranial extra-axial tumour.Total resection

MIB-1 P53

Recurrent tumour three years later

SA SA

MSA M SA M SA

M SA SAB

EMA SMA

CD10 MIB-1 P53

SA

SA

M M

B

RETICULIN

Additional two cases with similar clinical course and histological

features.

N

Case #2: 55 y.o.only meningioma in the first surgery

Only myofibroblastic sarcoma in two subsequent surgeries.Four year survival.

Recurrent tumour one year later: only sarcoma

SMA +

Reticulin

Fibronexus

Myofilaments

c

g h

SMA

GFAP SMA

EMA P53CD10

Case #3: 64 yo: first surgery: atypical meningioma

Recurrence, 5 yrs later: Mixed meningioma/sarcoma

MIB: 10%+

a

b c

Case #3 Myofibroblastic differentiation of tumour cells

MYOFIBROBLASTIC SARCOMA (MFSA) IN ANAPLASTIC MENINGIOMA

• Three similar cases in personal collection: all developed in recurrent malignant meningiomas invading brain

• Two mixed, myofibroblastic sarcoma/meningioma and one pure myofibroblastic sarcoma: MFSA strongly positive for smooth muscle actin, vimentin and reticulin

• All developed on the side of infiltrated brain• All show high MIB-1 and P53 immunoreactivity• All rapid growth of recurrent tumour

• DIAGNOSIS: MYOFIBROBLASTIC VARIANT OF ANAPLASTIC MENINGIOMA (“METAPLASTIC”)