肉腫様腎細胞癌 Sarcomatoid renal cell carcinoma の4例

Abstract

We herein report four cases of sarcomatoid renal cell carcinoma. These cases comprised 4.1% of the 98 patients with renal cell carcinoma treated in our department during the past 13 years. It is confirmed that renal cell carcinoma with a sarcomatoid component often shows local invasion, distant metastasis, rapid growth and poor prognosis. In Mian's series, the percentage of sarcomatoid component ( or = 25%) was associated with decreased survival time, but was independent of stage. The pathological stage was pT3b N0 M0 in case 1, pT1b N0 M1 in case 2, pT3b N0 M1 in case 3 and pT1a N0 M1 in case 4. The pT1 sarcomatoid renal cell carcinoma in case 2 and case 4, who developed poor prognosis, was composed of 60 and 80% sarcomatoid change, respectively. However in case 3 with a pathological stage of pT3, the patient is alive 35 months after resection, because the extent of sarcomatoid component was 25%. The prognosis of patients with sarcomatoid renal cell carcinoma depends on not only disease stage and tumor grade but also the pathological extent of sarcomatoid component.

患者は全例男で、肉腫様腎細胞癌であった。症例1:65歳はINF療法を拒否し肺転移による右背部痛増強で緩和療法を行ったが2ヵ月後癌死した。病理組織学的肉腫様成分(占拠率)は98%以上であった。症例2:44歳は骨転移に伴う疼痛に対しIFN-αbased therapy と緩和療法を先行し、腎摘出後骨転移に放射線外照射したが脳転移が出現した。γナイフ放射線を追加し、肋骨転移、胸壁皮膚転移で術後21ヵ月に癌死に至った。占拠率は60%であった。症例3:55歳は術後のIFN-αbased therapyを、肺転移の増大でIL-2 based therapyに変更したがさらに増大し、sorafenib tosilate投与で縮小して術後35ヵ月現在、生存中であった。腎腫瘍径9.0cm、pT3bの肉腫様成分25%の低占拠率であった。症例4:59歳は術後IFN-αbase therapy 継続後に肺転移が増大しIL-2 based therapy へ変更するも増大し、IFN-αbased therapy に変更したが胸水を伴う肺転移で術後19ヵ月に癌死に至った。腎腫瘍径2.5cm、pT1a、占拠率は80%であった。