高分化型脂肪肉腫の治療成績と治療戦略

Clinical Outcomes and Surgical Strategy for Well-differentiated Liposarcoma

　背景：高分化型脂肪肉腫に対する切除縁には施設ごとにばらつきがあり，いまだ一定した見解は得られていない．

　対象と方法：手術的加療を行った高分化型脂肪肉腫45症例(初回手術41例，再手術4例)を検討した．

　結果：初回手術例のうち再発したものは，後腹膜腔内発生の1例のみであった．再手術症例では，再発までの期間は平均16.5年であった．45症例すべてで遠隔転移を生じた症例はなかった．

　まとめ：四肢発生例に限れば，筋力を大きく低下させないよう，腫瘍と正常組織との境界不明瞭な部位では，一部筋組織などの周囲軟部組織を含めた準広範切除を行い，神経・血管束に近接した部位や，周囲との境界が明瞭な部位では，辺縁切除を行う準広範切除術を施行することが妥当であると考えた．

　Background：The optimal surgical margin for well-differentiated liposarcoma remains controversial.

　Method：We reviewed the clinical outcomes of 45 patients with well-differentiated liposarcoma who underwent surgery at our institution during the past 2 decades.

　Outcome：In this series well-differentiated liposarcoma tended to arise in the lower extremity of elderly persons.　In many cases wide surgical excision caused muscle weakness because of the size of the tumor or tumor tissue infiltration of surrounding muscles.　The well-differentiated liposarcomas in our series grew slowly, even when they recurred, and no metastases were detected.

　Conclusions：Preservation of both neurovascular bundles and muscles is particularly important in elderly patients in order to maintain their ability to walk.　In view of the above factors, marginal excision accompanied by partial muscle resection (to prevent residual tumor masses) appears to be the most suitable surgical strategy for patients with well-differentiated liposarcoma, except in retroperitoneal cases.