Article Text

Download PDFPDF
Friend leukaemia integration-1 expression in malignant and benign tumours: a multiple tumour tissue microarray analysis using polyclonal antibody


Background: Friend leukaemia integration-1 (FLI-1) antibody is a useful marker for Ewing’s sarcoma/primitive neuroectodermal tumour (EWS/PNET) and vascular tumours. However, it is also expressed in subsets of lymphoblastic lymphoma, Merkel cell carcinoma (MCC) and desmoplastic small round cell tumour (DSRCT).

Aim: To determine expression of FLI-1 in various benign and malignant neoplasms, by immunohistochemical analysis on 4323 tumours using multiple tumour microarrays, as well as on whole sections.

Results: FLI-1 was expressed in 46/62 EWS/PNETs, 2/3 olfactory neuroblastomas, 7/102 small cell carcinomas of the lung, 10/34 MCCs, 1/14 rhabdomyosarcoma, 19/132 non-Hodgkin’s lymphomas, 2/3 DSRCTs, and in 53/74 benign and malignant vascular tumours. In addition, 27/508 squamous cell carcinomas, 19/837 adenocarcinomas, 10/400 urothelial bladder cancers, 1/40 basal cell carcinomas, 3/29 liposarcomas, 1/40 glioblastoma multiforme and 9/29 medullar carcinomas of the breast expressed FLI-1. The sensitivity and specificity of FLI-1 to distinguish EWS/PNET from all types of malignancies were 74.2% and 96.0%, respectively. Finally, the sensitivity and specificity of FLI-1 to distinguish EWS/PNET from other small round cell tumours (SRCTs) were 74.2% and 91.6%, respectively.

Conclusion: This study was the first to show that FLI-1 can be seen in a variety of solid tumours, some of which had never been explored before. This finding should be kept in mind, especially when using FLI-1 as a marker for finding the primary origin of poorly differentiated metastatic tumour. Finally, despite the expression of FLI-1 in numerous malignancies, it is still considered to be highly sensitive and specific in distinguishing EWS/PNET from other tumour types in general and from other SRCTs in particular.

  • DSRCT, desmoplastic small round cell tumour
  • EWS/PNET, Ewing’s sarcoma/primitive neuroectodermal tumour
  • FLI-1, friend leukaemia integration-1
  • MCC, Merkel cell carcinoma
  • NHL, non-Hodgkin’s lymphoma
  • ONB, olfactory neuroblastoma
  • RMS, rhabdomyosarcoma
  • SRCT, small round cell tumour

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.