Chemotherapy in soft tissue sarcoma. The Scandinavian Sarcoma Group experience

SARC006: Phase II Trial of Chemotherapy in Sporadic and Neurofibromatosis Type 1 Associated Chemotherapy-Naive Malignant Peripheral Nerve Sheath Tumors

Background

Worse chemotherapy response for neurofibromatosis type 1- (NF1-) associated compared to sporadic malignant peripheral nerve sheath tumors (MPNST) has been reported.

Methods

We evaluated the objective response (OR) rate of patients with AJCC Stage III/IV chemotherapy-naive NF1 MPNST versus sporadic MPNST after 4 cycles of neoadjuvant chemotherapy, 2 cycles of ifosfamide/doxorubicin, and 2 cycles of ifosfamide/etoposide. A Simon optimal two-stage design was used (target response rate 40%).

Results

34 NF1 (median age 33 years) and 14 sporadic (median age 40 years) MPNST patients enrolled. Five of 28 (17.9%) evaluable NF1 MPNST patients had a partial response (PR), as did 4 of 9 (44.4%) patients with sporadic MPNST. Stable disease (SD) was achieved in 22 NF1 and 4 sporadic MPNST patients. In both strata, results in the initial stages met criteria for expansion of enrollment. Only 1 additional PR was observed in the expanded NF1 stratum. Enrollment was slower than expected and the trial closed before full accrual.

Conclusions

This trial was not powered to detect differences in response rates between NF1 and sporadic MPNST. While the OR rate was lower in NF1 compared to sporadic MPNST, qualitative responses were similar, and disease stabilization was achieved in most patients.

Expression of HER1/EGFR protein in human soft tissue sarcomas

AIM

To measure epidermal growth factor receptor (HER1/EGFR) expression in a range of soft tissue sarcoma (STS) patient samples.

METHOD

HER1/EGFR expression was examined by immunohistochemistry in archival tissues of 46 STS patients.

RESULTS

HER1/EGFR was positively expressed in 36/46 of STS samples distributed among different histological types. The levels of HER1/EGFR in STS tumour tissues in positive samples were higher compared to those in nearby normal tissues.

CONCLUSION

HER1/EGFR is significantly expressed in soft tissue sarcomas, which is a finding reflected in other series. The significance of this finding for targeted therapy is as yet unknown.

Human DNA topoisomerase I: An anticancer drug target present in human sarcomas

New anticancer drugs targeting DNA topoisomerase I (topo I) are showing activity against human sarcomas. Laboratory studies have indicated that cells responsive to topo I-targeted drugs have elevated levels of topo I, require active DNA replication, and may require a functional apoptotic pathway. In this study, we evaluated these potential markers of topo I-targeted drug sensitivity in 55 cases of human sarcoma (42 high grade, 4 intermediate grade, and 9 low grade). By immunohistochemical staining, we observed elevated topo I expression in 20 of 55 neoplasms (36%). Immunohistochemical staining for the proliferation marker DNA topoisomerase II-alpha (topo II-alpha), showed that 15 of 55 neoplasms (27%) had topo II-alpha indices >50, indicating a large number of actively cycling tumor cells. Abnormal p53 expression was observed in 19 of the 55 cases (35%). None of the cases were interpreted as positive for ALK-1. To complement our immunohistochemical staining of topo I, we isolated functionally active topo I from extracts of a human sarcoma. These isolates demonstrated that sarcoma topo I is sensitive to topo I-targeted anticancer drugs. Of the 55 cases of human sarcoma, 7 (13%) had high levels of topo I, a large number of cycling tumor cells, and normal p53 expression. These are the molecular parameters that might suggest responsiveness to drugs targeting topo I.

Monitoring referral and treatment in soft tissue sarcoma: study based on 1,851 patients from the Scandinavian Sarcoma Group Register

This report is based on 1.851 adult patients with soft tissue sarcoma (STS) of the extremities or trunk wall diagnosed between 1986 and 1997 and reported from all tertiary referral centers in Norway and Sweden. The median age at diagnosis was 65 years and the male-to-female ratio was 1.1:1. One third of the tumors were subcutaneous, one third deep, intramuscular and one third deep, extramuscular. The median size was 7 (1-35) cm and 75% were high grade (III-IV). Metastases at presentation were diagnosed in 8% of the patients. Two thirds of STS patients were referred before surgery and the referral practices have improved during the study. The preoperative morphologic diagnosis was made with fine-needle aspiration cytology in 81%, core-needle biopsy in 9% and incisional biopsy in 10%. The frequency of amputations has decreased from 15% in 198688 to 9% in 1995-1997. A wide surgical margin was achieved in 77% of subcutaneous and 60% of deep-seated lesions. Overall, 24% of operated STS patients had adjuvant radiotherapy. The use of such therapy at sarcoma centers increased from 20% 1986-88 to 30% in 1995-97. Follow-up has been reported in 96% of the patients. The cumulative local recurrence rate was 0.20 at 5 years and 0.24 at 10 years. The 5-year metastasis-free survival rate was 0.70.