Willemina M. Molenaar

Soft tissue leiomyosarcomas and malignant gastrointestinal stromal tumors: Differences in clinical outcome and expression of multidrug resistance proteins

PURPOSE Several studies have reported clinical behavior and chemotherapy resistance in leiomyosarcomas, but these studies did not differentiate between soft tissue leiomyosarcomas (LMS) and malignant gastrointestinal stromal tumors (GIST). Multidrug resistance (MDR) has been associated with the expression of P-glycoprotein (P-gp), multidrug resistance protein (MRP(1)), and lung resistance protein (LRP). The aim of the present study was to compare LMS and GIST with respect to clinical outcome and MDR parameters. PATIENTS AND METHODS Clinical outcome was evaluated in 29 patients with a primary deep-seated LMS and 26 patients with a primary malignant GIST. Paraffin-embedded material, available for 26 patients with LMS and 25 with GIST, was used for immunohistochemical detection of P-gp, MRP(1), LRP, and c-kit. RESULTS Mean overall survival (OS) was 72 months for LMS patients and 31 months for GIST patients (P: <.05). Metastases occurred in 16 (59%) of 27 assessable LMS patients and in 10 (56%) of 18 assessable GIST patients. LMS predominantly metastasized to the lungs (14 of 16 patients), whereas GIST tended to spread to the liver (five of 10 patients) and the abdominal cavity (three of 10 patients; P: <.001). P-gp and MRP(1) expression was more pronounced in GIST than in LMS (P: <.05): the mean percentage of P-gp expressing cells was 13.4% in patients with LMS and 38.4% in patients with GIST, and the mean percentage MRP(1) expressing cells was 13.3% in patients with LMS and 35.4% in patients with GIST. LRP expression did not differ between LMS and GIST. c-kit was expressed in 5% of the LMS patients and in 68% of the GIST patients. CONCLUSION LMS patients have a better survival than GIST patients, and the metastatic pattern is different. Expression of MDR proteins in LMS is less pronounced than in GIST.

Malignant peripheral nerve sheath tumors in patients with and without neurofibromatosis.

Malignant peripheral nerve sheath tumors (MPNST) are rare. They account for 10% of all soft tissue sarcomas. The incidence of MPNST in patients with neurofibromatosis type 1 (NF-1) is 4%. A retrospective study was undertaken to evaluate the prognosis of patients with MPNST and NF-1 vs patients with MPNST alone. Twenty-two patients with MPNST were diagnosed. The MPNST was diagnosed with NF-1 in 11 patients (50%). Treatment was defined as curative in 20 patients (90%), non-curative in one patient (5%), and one patient received no treatment. The median disease-free survival (DFS) was 14 months (range 0-153 months). The median overall survival 24 months (range 1-153 months). There were three patients with isolated local failures (14%), four patients with local and distant failures (18%), and seven patients with isolated distant failures (32%). There was no statistical difference between patients with and without NF-1. Five patients with NF-1 developed a second MPNST (45%), none of the patients without NF-1 did (P = 0.018). A statistically worse survival was found when the duration of the first symptoms had been longer than six months. Patients with MPNST have a poor prognosis with a high risk for local and distant failures (> 50%). There is no statistical difference in the final outcome for MPNST with or without NF-1, but patients with NF-1 have a high risk for developing a second MPNST.

Results of isolated regional perfusion in the treatment of malignant soft tissue tumors of the extremities

High‐grade soft tissue sarcomas of the extremities continue to pose problems of local disease control and deaths from distant metastases. Between 1969 and 1976, eight patients with primary and six with recurrent high‐grade soft tissue sarcomas of the extremities were treated by isolated regional perfusion with cytostatics and local excision. None received systemic adjuvant chemotherapy or external‐beam radiotherapy. During the follow‐up (median, 13 years) five patients (36%) developed distant metastases. One was cured after resection of a pulmonary metastasis. In one other patient (7%) recurrent local disease was diagnosed after 48 months; he was cured after resection of the local lesion followed by postoperative external beam radiotherapy. The actuarial 5‐year and 10‐year survival was 69%. Treatment caused no cardiovascular complications and there was no postoperative mortality.

Analysis of proliferation and apoptosis in brain gliomas : Prognostic and clinical value

With the introduction of new (immuno-)histochemical techniques it is now possible to assess rates of proliferation and apoptosis in brain gliomas using archival paraffin embedded material. As proliferation and apoptosis are related to tumour growth rate quantification of these processes has prognostic value and is related to tumour grading. In this study we assessed the proliferation rate by measuring the Ki-67 labelling index using the MIB-1 antibody (MIB-LI) and the apoptotic rate using the in situ labelling of DNA strand breaks with TUNEL (TUNEL-LI) in 315 supratentorial gliomas. MIB-LI and TUNEL-LI in astrocytomas (A) where significantly lower compared to anaplastic astrocytomas (AA), glioblastomas (GBM) and oligodendroglial tumours [oligodendrogliomas (O) and anaplastic oligodendrogliomas (AO)]. MIB-LI and TUNEL-LI were significantly lower in AA compared to GBM. In astrocytic tumours MIB-LI and TUNEL-LI appeared to be correlated.As the distinction between A and AA is of clinical value but can be difficult histomorphologically we analysed the prognostic value of MIB-LI and TUNEL-LI in gliomas with particular emphasis on A and AA. MIB-LI below 10% was of prognostic value in A and AA, O and AO but not in GBM on univariate survival analysis. TUNEL-LI was of no prognostic value. With multivariate survival analysis MIB-LI lost prognostic significance in O and AO. Astrocytomas with a gemistocytic component (AG) are similar to A with respect to survival and MIB-LI and TUNEL-LI. MIB-LI is of independent prognostic value in A and AA. Assessment of MIB-LI in A and AA can be used as an aid in distinguishing A and AA.

Distinct Xp11.2 breakpoint regions in synovial sarcoma revealed by metaphase and interphase FISH: relationship to histologic subtypes.

Fluorescence in situ hybridization (FISH) and molecular analyses of synovial sarcomas with cytogenetically similar (X;18)(p11.2;q11.2) translocations have revealed two alternative breakpoint regions in Xp11.2, one residing in the ornithine aminotransferase-like 1 (OATL1) region and the other one in the related but distinct OATL2 region. As these results were obtained by different groups, we set out to evaluate an extended series of tumors with special emphasis on the two possible X-related breakpoint regions. Together, seven synovial sarcomas were identified with a break in the OATL1 region and six with a break near OATL2, thereby confirming the actual existence of the two alternative Xp breakpoint regions. We speculate that there seems to be a relationship between the occurrence of these breakpoint regions and the histologic phenotype of the tumors, with a predominance of OATL1-related breakpoints in the classical biphasic tumors and of OATL2-related breakpoints in the monophasic fibrous tumors.

Feasibility and Efficacy of External Beam Radiotherapy after Hyperthermic Isolated Limb Perfusion with TNF-α and Melphalan for Limb-saving Treatment in Locally Advanced Extremity Soft-tissue Sarcoma

Abstract Purpose: Hyperthermic isolated limb perfusion (HILP) with tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), and melphalan is associated with a dramatic antitumor effect in locally advanced extremity soft-tissue sarcomas (STS). The aim of this study was to demonstrate the feasibility and efficacy of adjuvant radiotherapy after HILP with TNF-α, IFN-γ, and melphalan and delayed surgical resection. Methods and Materials: Between 1991 and 1995, 34 patients—16 males and 18 females, median age 50 (range 18–80) years—underwent HILP for locally advanced extremity STS. Resection of the residual tumor mass was performed in most patients after 6–8 weeks. Fifteen patients with histopathological viable tumor after resection received adjuvent 60–70 Gy external beam radiotherapy (EBRT) (44%, HILP + EBRT group). Nineteen patients received HILP without adjuvent EBRT (56%, HILP-only group). Five patients in the HILP-only group had also distant metastases (15%) and received HILP as a palliative treatment. Treatment morbidity, local recurrences, and regional and distant metastases were scored. Results: During a median follow-up of 34 months (range 8–54), limb salvage was achieved in 29 patients (85%): 14 patients after HILP + EBRT and 15 patients after HILP only. None of the patients from the HILP + EBRT group developed local recurrences; however, five patients from the HILP-only did (26%) ( p Conclusion: Adjuvent EBRT after HILP with TNF-α, IFN-γ, and melphalan and delayed tumor resection of locally advanced extremity STS is feasible and may increase local tumor control without increasing treatment morbidity.

Mature teratoma identified after postchemotherapy surgery in patients with disseminated nonseminomatous testicular germ cell tumors

Mature teratoma is often found in resected retroperitoneal residual tumor masses (RRTM) after chemotherapy for disseminated nonseminomatous testicular germ cell tumors (NSTGCT). The aim of this report is to describe the clinical course of patients after resection of residual teratoma, with particular emphasis on relapse with either growing mature teratoma or secondary non‐germ cell malignancy.

Computer-assisted cytogenetic analysis of 51 malignant peripheral-nerve-sheath tumors: Sporadic Vs. neurofibromatosis-type-1-associated malignant schwannomas

Cytogenetic studies in small groups of patients with malignant peripheral‐nerve‐sheath tumors (MPNST) revealed complex karyotypes with no consistent changes. A computer‐assisted cytogenetic analysis using a cytogenetic database was performed to determine recurrent cytogenetic alterations in 51 MPNSTs (44 from the literature and 7 new cases) and to allow direct cytogenetic comparison between NF‐1‐associated and sporadic MPNSTs. Significant loss (p < 0.05) was observed in the chromosomal regions 9p2, 11p1, 11q2 and 18p1. Also, loss in 1p3, 9p1, 11q1, 12q2, 17p1, 18q1‐q2, 19p1, 22q1, X and Y was detected. Gain of chromosomal material was found in chromosome 7, especially 7q1 (p < 0.05). Most involved breakpoints were: 1p13, 1q21, 7p22, 9p11, 17p11, 17q11, 22q11. Cytogenetic differences between NF‐1‐associated and sporadic MPNSTs included a relative loss of chromosomal material in NF‐1‐associated MPNSTs in 1p3, 4p1 and 21p1‐q2 and a relative gain in 15p1‐q1. Differences in breakpoints between the NF‐1 associated and the sporadic MPNST group were observed in 1p21‐22 (28% of NF‐1 vs. 0% of sporadic MPNSTs), 1p32‐34 (17% vs. 0%), 8p11‐12 (7% vs. 27%) and 17q10‐12 (24% vs. 7%). This approach, in which the cytogenetic results of various reports are combined, shows that losses in 9p2 and gains in 7q1 could be of oncogenetic importance in MPNSTs. Loss of 17q1, on which the NF‐1 gene has been located (17q11.2), is not a common cytogenetic finding in NF‐1‐associated MPNSTs. The observed differences between NF‐1‐associated and sporadic MPNSTs might reflect different oncogenetic pathways. Int. J. Cancer 83:171–178, 1999.

High frequency of TP53 mutations in juvenile pilocytic astrocytomas indicates role of TP53 in the development of these tumors.

In adults, the TP53 tumor suppressor gene is frequently mutated in astrocytic brain tumors which is supposed to represent an early event in their development. In juvenile pilocytic and low‐grade astrocytomas, however, TP53 mutations have until now been reported as rare, which has led to the suggestion that these tumors may follow a different molecular pathogenesis with an involvement of genes other than TP53. Our analysis of 20 pilocytic and two lowgrade astrocytomas of childhood, based on a comprehensive denaturing gradient gel electrophoresis (DGGE) mutation detection assay of the entire coding region, including all splice site junctions of TP53, showed mutations considered as causative in 7 of the 20 (35%) pilocytic astrocytomas and in one of the two low‐grade astrocytomas. Our finding is significantly different from the mutation frequency of 1.3% (2/155) previously reported for these tumor types. This may be attributed to the mutation detection system used, which also detects mutations occurring outside the evolutionary conserved region of TP53. Our results suggest that, contrary to the present notion, TP53 mutations may well play a role in the development of juvenile astrocytomas. Furthermore, no mutations were found in tumors of patients with progression of residual tumor after postoperative follow‐up. This suggests that TP53 mutations may be associated with less aggressive forms of juvenile astrocytomas, analogous to the situation in adult astrocytomas.

The proliferative potential of the pilocytic astrocytoma : The relation between MIB-1 labeling and clinical and neuro-radiological follow-up

The proliferative potential of 39 pilocytic and 5 low grade astrocytomas was studied in relation to the Ki-67 activity as measured by the MIB-1 Labelings Index. The results were correlated to the biological behaviour of the tumor as measured by clinical and neuro-radiological (CT- or MRI-scans) follow-up of the patient. This study was undertaken to answer the question whether MIB-1 expression reflects differences in biological behaviour of these tumors, such as rapid progression of residual tumor or stable remaining tumor. MIB-1 LI values ranged from 0 to 19% in the group of pilocytic astrocytomas (mean 4,2%) and from 0 to 15% in the 5 low grade astrocytomas (mean 4,2%). All patients were operated and 23 of them had incomplete tumor resection as proven on postoperative neuro-imaging studies. Those 23 patients could be subdivided into two groups; one without progression of residual tumor during follow-up (n=12) and the other with tumor progression (n=11). mean MIB-1 LI in the group with ‘quiescent’ tumor tended to be lower than in the group with progressive tumor: 3,3% vs. 6,6%. Residual tumors which were negative for MIB-1 staining showed fewer progressions of residual tumor compared to those being positive for MIB-1 staining, however this difference was not significant (p=0, 15, Fisher exact test). Tumor samples of a second operation of the same patient had lower MIB-1 LI values than those of the samples taken at first operation. The proliferating potential seemed to be decreased after part of the tumor was resected. Pilocytic astrocytomas with a negative MIB-1 LI are unlikely to show progression of residual tumor after partial resection. MIB-1 staining might be an additional tool in determining the frequency and duration of follow-up and in making decisions regarding further treatment of a patient operated for a pilocytic astrocytoma with residual tumor.