異時性多発肺癌に対する縮小手術の治療成績

Outcomes of Sublobar Resection for the Patients with a Metachronous Multiple Lung Cancer

肺癌切除例の予後の向上に伴い，多発肺癌の発生頻度は増加傾向にあると報告されている1）．多発肺癌は発見時期により同時性または異時性に分けられるが，診断と治療法に明確な指針がなく，治療戦略の決定に苦慮することがある．このうち診断については，肺癌術後の異時性多発肺癌（第2癌）の場合，肺転移との鑑別診断は病理学的検討を行っても困難な場合が少なくない．一方で治療に関しては，患者の高齢化や肺切除後のために呼吸機能が低下している症例も多く，機能温存の目的で縮小手術を選択せざるをえない場合にも直面する．より適切な異時性多発肺癌の診療を行うためには，異時性多発肺癌に対する現状把握と治療成績の検証が必要である．

Objectives：In order to perform appropriate treatment for metachronous multiple lung cancer, it is important to verify the surgical treatment outcome. We evaluated the surgical outcome of metachronous multiple lung cancer focused on the sublobar resection of metachronous second lung cancer.

Methods：The subjects of this study were 1,513 cases that underwent radical resection for primary lung cancer in our institution from January 2004 to April 2020. We selected 23 （1.5％） patients who underwent lobectomy for initial primary lung cancer and underwent sublobar resection for metachronous second lung cancer.

Results：The median follow-up period from resection for initial primary lung cancer to resection for metachronous second lung cancer was 49 months. Regarding the analyses for survival, the median follow-up period after resection for initial primary lung cancer was 79 months with a five-year overall survival rate of 80.4％ and a five-year relapse-free survival rate of 75.6％. Whereas the median follow-up period after resection for metachronous second lung cancer was 27 months with a five-year overall survival rate of 55.8％ and a five-year relapse-free survival rate was 48.4％.

Conclusions：The long-term outcome for sublobar resection for metachronous second lung cancer was similar to previous reports and the rate of complications tended to be low.