Israel Medical Association Journal

Background: Trabectedin is a marine-derived chemotherapy, which has received U.S. Food and Drug Administration approval for use in anthracycline-resistant advanced soft tissue sarcoma (STS), especially liposarcoma and leiomyosarcoma (L-sarcomas).

Objectives: To describe our 10 year real-life experience with trabectedin regarding safety and efficacy in a cohort of 86 patients.

Methods: In our study cohort, 46.51% were diagnosed with liposarcoma and 43.02% with leiomyosarcoma. A total of 703 cycles of trabectedin were given, with a median of five cycles per patient (range 1–59). Median overall survival was 13.5 months for the whole cohort, 11 months for liposarcoma patients (range 1–63), and 15 months for leiomyosarcoma patients (range 1–35).

Results: There was no statistically significant difference in progression free survival when stratified according to previous treatment lines given. Trabectedin exhibited a favorable safety profile, with only 22% requiring dose reductions. Grade 3 and higher toxicity was noted in 25% of the patients, mostly due to myelosuppression. There were no treatment-related deaths.

Conclusions: Trabectedin is a safe and effective drug for treating advanced STS. Our results reflect real-life data with patients receiving the drug as a third and even fourth line of treatment, or with a suboptimal performance status, yet achieving impressive clinical benefit rates and survival.

Background: The diagnosis of gastrointestinal stromal tumors is based on documentation of c-KIT and platelet-derived growth factor-alpha receptors or specific c-KIT mutations. Before the diagnosis of GIST[1] was possible, all cases had been classified as sarcomas or benign tumors.

Objectives: To identify cases of GIST formerly diagnosed as abdominal or retroperitoneal mesenchymal tumors.

Methods: We reviewed the archive material on all surgical cases diagnosed as gastrointestinal related malignant mesenchymal tumors or GIST in our medical center during the last decade (1995–2004).

Results: Sixty-eight cases of retroperitoneal soft tissue sarcoma were identified. Thirty-eight were reconfirmed to be GIST, 19 were newly diagnosed as GIST (the hidden cases), 8 cases were re-diagnosed as mesenchymal tumors, and 3 cases of sarcoma remained sarcomas. Of all the GIST tumors, c-KIT-positive and PDGFRα[2]-positive tumors were more characteristic of primary gastric tumors, while c-KIT-positive and PDGFRα-negative tumors were found in the colorectal area. The c-KIT-negative and PDGFRα-positive cases were of gastric origin.

Conclusions: Any c-KIT-negative malignant mesenchymal mass located near the proximal gastrointestinal tract should also be stained for PDGFRα to differentiate between GIST and other soft tissue sarcomas. Practically, formerly diagnosed abdominal or retroperitoneal soft tissue sarcomas should be reviewed to identify patients with misdiagnosed GIST and thereby avoid future unnecessary and ineffective chemotherapy.

Background: There are radiobiologic and technical advantages to the use of interstitial brachytherapy alone or as an adjunct to external beam radiotherapy in the postoperative treatment of soft tissue sarcomas.

Objectives: To review the experience of the Rambam Medical Center in implementing interstitial brachytherapy in the treatment of 32 patients with soft tissue sarcomas.

Methods: Thirty-two patients with variously located soft tissue sarcomas were managed with a combination of surgery and brachytherapy of the tumor bed, with or without EBRT[1]. In 27 of 32 patients, brachytherapy catheters were placed intraoperatively, while in 5 patients the implant was performed as a separate postoperative procedure. Twenty-seven patients received low dose-rate brachytherapy with iridium-192 seeds. Five patients received fractionated high dose-rate brachytherapy using the microSelectron machine.

Results: With a median follow-up of 36 months, the overall local control rate was 87.5%. Four of 32 patients (13%) failed locally at the implant site, and 6 (19%) developed lung metastasis. Two of the five patients with lung metastasis had a local recurrence as well. At the time of analysis, eight patients had died of sarcoma (disease-specific mortality rate was 25%), while three had died of intercurrent causes. The 5 year actuarial disease-free survival rate was 56%, and the 5 year actuarial overall survival was 70%. Five patients (16%) developed severe wound complications following surgery/brachytherapy, and six patients (19%) developed late local toxicity (fibrosis and telangiectasia).

Conclusions: Wide local excision followed by interstitial brachytherapy has resulted in an 87.5% local control rate with a 17% local complication rate.

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