Aims

Myxofibrosarcomas (MFSs) are malignant soft-tissue sarcomas characteristically presenting as painless slowly growing masses in the extremities. Locally infiltrative growth means that the risk of local recurrence is high. We reviewed our experience to make recommendations about resection strategies and the role of the multidisciplinary team in the management of these tumours.

Introduction: The Literature is divisive in regards to the superiority of Core versus Incision biopsy in the diagnosis of Soft Tissue Tumour. The Aim of the study is to compare the accuracy of Trucut biopsy and open Incision Biopsy.

Methods: This was a retrospective review of case notes and pathology records. Between January 2006 and June 2007, 34 Trucut biopsies were performed without imaging guidance in an outpatient setting and 57 incision biopsies were performed as an inpatient on patients referred with a soft tissue mass to our service. In each case the accuracy of biopsy in providing a diagnostic sample, in determining the tumour type and the histological grade of tumour were calculated. For each biopsy method we compared the diagnosis after biopsy with the final diagnosis after excision. The proportion of diagnostic biopsies was calculated, as were the sensitivity and specificity of each technique in providing a diagnosis. Fisher’s exact test was used to test for differences in the techniques.

Results: In this series there were 41 soft tissue sarcomas, 8 metastatic adenocarcinoma soft tissue deposits, 7 lymphomas, 1 non soft tissue sarcoma, 32 benign soft tissue tumours and 1 infection. 33/34 Trucut biopsies and 55/57 open biopsies provided the final histological diagnosis (p=1). There was no statistical difference between the techniques in the accuracy of identifying the type and grade of soft tissue sarcoma

Discussion: Trucut biopsy is equivalent to incision biopsy in its accuracy of diagnosing soft tissue tumours. Biopsy in an outpatient setting for appropriate tumours is cost effective and likely shortens the time to diagnosis. Our results are comparable to published data from other centres.

The soft tissue sarcomas (STS) are a diverse collection of malignant tumours of the connective tissues arising from the primitive mesoderm and ectoderm. While the primary treatment of most is surgery, chemotherapy can be offered to patients presenting with locally advanced or metastatic disease although sarcomas are resistant to the majority of anticancer drugs. The reasons for this are not fully understood but it is thought that p53 abnormalities and mdm2 overexpression may be involved. Samples from twenty eight adult patients with soft tissue sarcomas have been analysed for p53 mutations in exons 4 to 9 both by denaturing high performance liquid chromatography (dHPLC) and by direct automated sequencing. By sequencing we found mutations in 7/28 patients, giving a mutation rate of 25%. 4/6 were point mutations in exons 5, 7 and 8 and the remaining three were deletions in exons 4, 7 and 8. Six of these samples gave abnormalities in dHPLC analysis with a concordance rate of 97.5% between the sequencing and dHPLC data. Thirty nine and forty samples have been assessed by immunohistochemistry for p53 and mdm2 expression respectively. Do7 antibody which recognises the N terminus of p53 and F4-14 which recognises the carboxy-terminus of mdm2 were used. Immunohistochemistry was scored semiquantitatively by two independent observers and the results scored accordingly: low (< 20%), intermediate (20–80%) and high (> 80%). The initial results showed that 23/40 (58%) of patients were high staining for mdm2 in contrast to only 15/39 (38%) of patients for p53. All patients with deletions in p53 had intermediate staining for mdm2. 2/3 of these had intermediate staining for p53 and 1/3 had high staining for p53. One patient with a point mutation had high staining for both p53 and mdm2 but the other two have yet to be analysed by immunohistochemistry. These results confirm the overexpression of mdm2 in STS. Future experiments are planned using fluorescent in situ hydridisation (FISH) to determine whether MDM2 amplification is one of the mechanisms involved in mdm2 overexpression.