Aug 20, 2008 - 4 Consulting Statistician, Romelanda, Sweden. 5 Department of Orthopedics, .... Surgical margin, defined as ''intralesional'' if mac- roscopic or ...
1649
Liposarcoma Outcome Based on the Scandinavian Sarcoma Group Register
Katarina Engstr€om, MD, PhD1 Peter Bergh, MD, PhD2 Pelle Gustafson, MD, PhD3 Ragnar Hultborn, MD, PhD1 Helena Johansson4 Rickard L€ofvenberg, MD, PhD5 Olga Zaikova, MD6 Clement Trovik, MD, PhD7 Ola Wahlstr€om, MD, PhD8 Henrik C.F. Bauer, MD, PhD9
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
1
Department of Oncology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden. 2
Department of Orthopedics, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden. 3
Department of Orthopedics, Lund University Hospital, Lund, Sweden. 4
Consulting Statistician, Romelanda, Sweden.
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 liposar-
5
Department of Orthopedics, Norrland University ˚ , Sweden. Hospital, Umea
coma with a round cell component. Radiotherapy showed significant effect on
6
CONCLUSIONS. Patients with liposarcoma should be treated at specialized centers.
local recurrence rate for the same grade and margin.
Department of Orthopedics, The Norwegian Radium Hospital, Montebello, Oslo, Norway.
Postoperative radiotherapy decreases the local recurrence rate. To maintain qual-
7
ity and provide support for further trials, reporting to quality registers is crucial.
Department of Orthopedics, Haukeland Hospital, Bergen, Norway.
Cancer 2008;113:1649-56. 2008 American Cancer Society.
8
Department of Orthopedics, Linköping University Hospital, Linköping, Sweden. 9
Department of Orthopedics, Karolinska Hospital, Stockholm, Sweden. This work was supported by The King Gustaf V Jubilee Clinic Cancer Research Foundation, the Johan Jansson Foundation for Cancer Research, and the Scandinavian Sarcoma Group (SSG). We thank Professor Anders Oden, Professor in Biostatistics. Address for reprints: Katarina Engstr€om, MD, PhD, Department of Oncology, Sahlgrenska Academy, University of Gothenburg, SE-413 45 Gothenburg, Sweden; E-mail: katarina.engstrom@ oncology.gu.se Received December 20, 2007; revision received April 24, 2008; accepted May 15, 2008.
ª 2008 American Cancer Society
KEYWORDS: liposarcoma, Scandinavian Sarcoma Group, radiotherapy, local recurrence, metastasis.
L
iposarcoma is 1 of the most common soft tissue sarcomas and accounts for approximately 20% of these malignancies. The World Health Organization classification recognizes 5 subgroups of liposarcoma,1 all with different biological behavior. Most larger series are based on reviews of the experience of a single institution.2-9 The current study is based on patients with liposarcoma of the extremities or trunk wall, reported to the Scandinavian Sarcoma Group (SSG) Register by sarcoma centers in Norway and Sweden between 1986 and 1998. Approximately 90% of soft tissue sarcoma patients in Norway and Sweden are treated at specialized centers and, consequently, the SSG Register is considered population-based in these 2 countries.10
DOI 10.1002/cncr.23784 Published online 20 August 2008 in Wiley InterScience (www.interscience.wiley.com).
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CANCER
October 1, 2008 / Volume 113 / Number 7
The aim of this study was to investigate the occurrence of local recurrences, metastases, and survival data in relation to clinicopathological and treatment characteristics in a large group of liposarcoma patients meant to be treated according to the guidelines of the SSG.10
MATERIALS AND METHODS Patients All patients (N 5 319) reported by sarcoma centers in Norway and Sweden to the SSG Register between March 1, 1986, and December 31, 1998, and diagnosed as having liposarcoma of the superficial trunk and extremities were reviewed. The SSG Pathology Board11 reviewed histopathology, subtypes, and grade, without knowledge of clinical course. Seventyseven patients were excluded; 26 were reclassified as other type of sarcomas, 4 as other malignancies, 18 as benign lesions, and 29 were excluded for other reasons. Furthermore, 4 patients with metastases and 1 with gross tumor in whom complete local excision was not feasible and who refused amputation were excluded, leaving 237 patients for analysis. All patients were initially or subsequently referred to specialized sarcoma centers (5 in Sweden and 3 in Norway). The following factors with potential for prognostic importance regarding local recurrence and metastases were analyzed: Patient-related: Sex and age. Tumor-related: Size, site, lesion depth, grades I to IV according to Broders et al12 and Angervall et al,13 based on cellularity, pleomorphism, nuclear atypia, mitotic activity, and necrosis, as reviewed by Meis-Kindblom et al,11 and histological type. In the analyses, myxoid liposarcomas (MLSs) and round cell liposarcomas (RCLSs) were merged into 1 group and analyzed as RCLSs. The histological subtype MLS/RCLS was based on a subjective assessment of the percentage of round cells (>5% and .30 .034 .0033 .0058 .029 >.30 >.30 .11 >.30 .30 >.30 >.30 .24 >.30 >.30 >.30 >.30 .0092
Multivariate Analysis P
.018
.30 .30 >.30 .041
6.87 (2.31-20.44)
.0029y .0026 .0047 .0067 .080 >.30 >.30 >.30 .15 .15 0.053
