Winter Meeting 2011 - The Pathological Society of Great Britain ...

P81
Desmoplastic Small Round Cell Tumour of the Ilium associated
with a Variant EWS-WT1 Transcript
P SP Damato; MF Amary; S Butt; R Tirabosco; AM Flanagan
Royal National Orthopaedic Hospital, Stanmore, United Kingdom
Desmoplastic small round cell tumour is a rare aggressive neoplasm which typically
arises within the abdominal cavity of children and young adults. It is characterised by a
t(11;22)(p13;q12) translocation which results in the formation of an EWS-WT1 fusion
transcript. We report an unusual case of desmoplastic small round cell tumour arising
in the left ilium of a 31 year old man. Imaging showed diffuse sclerotic involvement of
the iliac wing with extension into the soft tissue to form masses at the medial and lateral
aspects. The patient underwent a core biopsy which revealed a high-grade ‘small round
cell tumour’ composed of cords and nests of cells surrounded by a desmoplastic stroma.
Immunohistochemistry showed that the tumour cells were positive for MNF116 and
desmin (dot-like positivity). EWS gene rearrangement was demonstrated by interphase
FISH but the most common EWS-WT1 7/8 fusion transcript was not detected by
RT-PCR. A variant EWS-WT1 fusion transcript was subsequently detected using primers
for EWS exon 9 and WT1 exon 8. Primary desmoplastic small round cell tumour of bone
is extremely rare with only three previously reported cases. Molecular confirmation of the
histological diagnosis is particularly important in cases arising in unusual sites. However,
it should be noted that variant fusion transcripts represent a potential pitfall in diagnosis.
P83
Diagnostic and Prognostic Role of Galectin 3 Expression in
Cutaneous Melanoma
P AG Abdou 1 ; MA Hammam 1 ; S El Farargy 1 ; AG Farag 1 ;
IN El Shafey 1 ; S Farouk 2 ; NF Elnaidany 3
1 Faculty of Medicine, Menofiya University, Shebein Elkom, Egypt;
2 Ahmed Maher Educational Hospital, Cairo, Egypt;
3 Faculty of Pharmacy, MSA University, October City, Egypt
Many of the histopathological criteria used to diagnose melanoma overlap with atypical
but otherwise benign naevi such as dysplastic or Spitz naevi. Galectin-3 is a member
of the galectin gene family and is expressed at elevated levels in a variety of neoplastic
cell types. The aim of the present study was to investigate the diagnostic value of
galectin-3 expression compared to HMB-45 (one of the established and widely used
immunohistochemical melanocytic markers) together with assessment of its prognostic
value in melanoma lesions. This study was carried out on 21 cases of melanoma and
20 benign pigmented naevi. Galectin-3 was expressed in all the examined benign and
malignant melanocytic lesions. The nucleocytoplasmic pattern of galectin-3 appeared
in malignant cases only with 42.86% sensitivity, 100% specificity and 70.73 % accuracy.
This pattern tended to be associated with thick melanoma (p=0.08) and reduced survival
(p=0.22). The intensity of galectin-3 assessed by H score was significantly of higher values
in malignant lesions compared to benign lesions (P