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Liposarcoma: outcome based on the Scandinavian Sarcoma Group register.

BACKGROUND
The aim was to study the clinicopathological characteristics, treatment, and outcome of liposarcoma in an unselected, population-based patient sample, and to establish whether treatment was according to the Scandinavian Sarcoma Group (SSG) treatment guidelines.


METHODS
The SSG Pathology Board reviewed 319 liposarcoma cases reported between 1986 and 1998. After the review, 237 patients without metastasis were analyzed for local recurrence rate in relation to surgical margins, radiotherapy, occurrence of metastasis, and survival.


RESULTS
Seventy-eight percent of the patients were primarily operated on at a sarcoma center, 45% with wide margins. All patients operated on outside the center had nonwide margins. Low-grade lesions constituted 67% of cases. Despite nonwide surgery, only 58% of high-grade lesions were treated with postoperative radiotherapy. The risk of local recurrence after nonwide surgery, without irradiation, was 47% for high-grade lesions. The estimated 10-year, local recurrence-free and metastasis-free survival in the low-grade group was 87% and 95%, respectively. In the high-grade group, it was 75% and 61%, respectively. Independent adverse prognostic factors for local recurrence were surgery outside a sarcoma center and histological type dedifferentiated liposarcoma. For metastases, they were old age, large tumor size, high grade, and histological type myxoid liposarcoma with a round cell component. Radiotherapy showed significant effect on local recurrence rate for the same grade and margin.


CONCLUSIONS
Patients with liposarcoma should be treated at specialized centers. Postoperative radiotherapy decreases the local recurrence rate. To maintain quality and provide support for further trials, reporting to quality registers is crucial.