Solitary fibrous tumour (SFT) is a fibrotic neoplasm, also previously designated as hemangiopericytoma. STAT6 is a protein for signal tranducers and activators of transcription (STAT) family which is involved in immune function and early cell growth. Oncogenic alteration of STAT6 plays an important role for specific driver for tumour genesis of solitary fibrous tumour via NAB2-STAT6 fusion gene. The aim of the study was to compare and evaluate STAT6 expression between SFT and other soft tissue histological mimics. We evaluated a total of 30 cases material formalin fixed paraffin embedded tissue block previously diagnosed SFT cases (n=14) and soft tissue tumours mimic cases (n=16) over period of 15 years. Fourteen SFT cases (100%) showed nuclear expression of STAT6, which was diffuse and intense. All other tumour types were negative for STAT6, except for one case of dedifferentiated liposarcoma, one gastrointestinal stromal tumour and one spindle cell lipoma, which showed weak non-specific cytoplasmic staining. Nuclear STAT6 expression is useful and reliable as adjunctive marker for solitary fibrous tumour when the diagnosis is inconclusive by conventional methods.
Estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) immunohistochemistry are important markers in the management of patient with breast carcinoma. In this study, we determine the concordance rate of ER, PR and HER2 immunohistochemistry markers between core needle biopsy (CNB) and excisional biopsy (EB) of breast carcinoma in patients of Universiti Kebangsaan Malaysia Medical Centre (UKMMC) from January 2002 until December 2012. A total of 93 female patients with CNB and subsequent EB were included in this retrospective descriptive study. Immunohistochemistry is used to determine ER, PR and HER2. ER and PR was graded using Allred score (0 to 8) while HER2 was scored from 0 to 3+. The markers between these two biopsies were compared to determine the concordance rate. In ER and PR, 93 samples were compared. ER was concordant in 80 cases (86.0%) and 13 cases (14.0%) was discordant. PR was concordant in 82 cases (88.2%) and discordant in 11 cases (11.8%). In HER2, 87 samples were compared and 62 cases (71.3%) were concordant while 25 cases (28.7%) were discordant. Concordance between CNB and EB was high for ER and PR. However, concordance rate for HER2 immunohistochemistry was less consistent. Overall, immunohistochemical analyses of CNB reflect the tumour marker status of the excised specimen.
Keywords: breast carcinoma, core needle biopsy, estrogen receptor, progesterone receptor, HER2
Gastrointestinal stromal tumour (GIST) is extremely rare with reported incidence of 20 per million per year. It is the most common mesenchymal tumour of the gastrointestinal tract. When it occurs at the pelvis in a female patient, it can be misleading to a gynaecological diagnosis. Non gynaecological diagnosis such as GIST must be considered in patients with pelvic mass presenting with atypical symptoms.