TREATMENT AND OUTCOME OF SOFT TISSUE LIPOSARCOMA

Abstract

Liposarcomas (LPS) are the most common soft tissue malignant tumor with a reported annual incidence of 2.5 per million people. The latest histopathologic classification of liposarcomas identifies three main groups: well-differentiated LPS; myxoid-round cell LPS; pleomorphic LPS. Dedifferentiated LPS is considered as a subgroup of well-differentiated LPS where there is an area of transition from a low grade to a high grade non lipogenic lesion (typically MFH or fibrosarcoma). The purpose of the present study was a retrospective review of the data of 146 consecutive patients affected by liposarcoma, with the aim to correlate the outcome of patients with treatment modalities and prognostic factors.

There were 89 males and 57 females with an average age of 54 years (range 16–92). The tumor grading following Broders criteria showed a low grade lesion in 48% of cases and a high grade lesion in 52% of cases. The histologic pattern showed a well differentiated liposarcoma in 25 patients (17%). The most frequent histologic finding was a myxoid liposarcoma in 55 cases (38%) while a round cell component of variable rate was seen in 22 cases (15%). A pleomorphic LPS was observed in 32 cases (22%). Dedifferentiated liposarcoma occurred only in 3 cases (2%). Surgery alone was performed in 31% of cases while chemotherapy (adriamycin and ifosfamide) and/or radiationtherapy were associated in 69% of cases. Brachytherapy was performed in 50 cases. Surgical margins resulted radical in 4 (2.5%) of cases, wide in 89 (61%), marginal in 45 (31%) and intralesional in 8 (5.5%) of cases.

In 10 cases (6.8%) a local recurrence occurred and in 33 cases (22.6%) a metastatic lesion was observed. Local recurrence were treated with surgical excision in 7 cases and with amputation in 3 cases. At an average follow up of 55 months, 68.5% of patients were continuosly disease free, 6.8% were disease free after local recurrence or metastasis excision or both, 4.8% were alive with disease, 14.4% were dead of the disease, 5.5% were dead of other cause. Eleven patients (7%) underwent an amputation, in 5 cases as first surgical procedure, in 3 cases after a local recurrence and in 3 cases for complications of the radiationtherapy. Local control was significantly correlated with the type of surgery at presentation and with surgical margins. Overall survival was significantly correlated with surgical margins, with grading and with the histotype of the tumor.

In the present series of soft tissue liposarcoma the combined treatment allowed limb salvage in 93% of cases (7% of amputations). Virgin lesions at presentation and free surgical margins resulted positive prognostic factors for local control. The histotype of the tumor, grading, and surgical margins resulted significative prognostic factors in survival, with round-cell and pleomorphic and high grade lesions showing the worse prognosis.