岡本 翔一^{1, 2}, 濃沼 淑芳¹, 葛 航晨¹, 相馬 聡一郎¹, 十合 晋作¹, 家永 浩樹³, 高橋 和久¹

Shouichi OKAMOTO^{1, 2}, Yoshika KOINUMA¹, Koushin KATSU¹, Soichiro SOMA¹, Shinsaku TOGO¹, Hiroki IENAGA³, Kazuhisa TAKAHASHI¹

¹順天堂大学大学院医学研究科呼吸器内科学, ²大阪府済生会茨木病院呼吸器内科, ³越谷市立病院呼吸器科

¹Division of Respiratory Medicine, Faculty of Medicine and Graduate School of Medicine, ²Department of Respiratory Medicine, Saiseikai Ibaraki Hospital, ³Department of Respiratory Medicine, Koshigaya Municipal Hospital

キーワード : chest ultrasound, interstitial lung diseases, plural line, pleural invasion, primary lung cancer

目的：超音波断層法は原発性肺癌における胸膜浸潤の検出に有効であるが，超音波診断所見と肉眼的胸膜浸潤所見（PL）および組織学的胸膜浸潤所見（pl）の不一致の要因については十分な検討はされていない．本研究の目的はこれらの所見を比較検討し，不一致に影響を及ぼした因子を明らかにすることである．対象と方法：対象は2014年から2017年までに超音波ガイド下穿刺術後に手術が行われた原発性肺癌の患者35例．穿刺術前に胸部超音波による胸膜浸潤の程度を評価して超音波断層法による肺癌胸膜浸潤所見（uP）を決定し，PLおよびplと比較検討した．所見一致群，過大評価群，過小評価群に分けて各種要因を検討した．結果と考察：uPとPL，uPとpl，PLとplの一致率はそれぞれ34.3％，28.6％，54.3％だった．PLに対するuPの過大評価群では所見一致群と比較して間質性変化が多く（P＝0.006），気腫性変化は少なかった（P＝0.023）．間質性変化を有する過大評価群では胸部CTにおける腫瘍周辺の胸膜不整が多く認められる傾向にあった（P＝0.066）．plに対するuPの過小評価群では肺尖部の腫瘍が多く（P＝0.022），uP2の過大評価群では横隔膜面の腫瘍が多く認められた（P＝0.024）．結語：間質性変化や肺尖部，横隔膜面の腫瘍の存在は超音波断層法による胸膜浸潤の評価に影響しうることが明らかになった．

Purpose: Ultrasonography is effective at detecting pleural invasion in primary lung cancer, but the factors underlying discordance between findings of pleural invasion according to ultrasonography, gross assessment (PL), and pathological assessment (pl) have not been fully investigated. The aims of the present study were to compare findings from these approaches and identify factors underlying discordant findings. Subjects and Methods: Subjects were 35 patients with primary lung cancer who underwent an ultrasound-guided puncture followed by surgery between 2014 and 2017. We assessed the extent of ultrasonographic pleural invasion prior to the puncture and then evaluated ultrasonographic grading of pleural invasion (uP) by lung cancer. We compared uP, PL, and pl, and examined various factors in patients with concordant findings, overestimated pleural invasion, and underestimated pleural invasion. Results: The rates of agreement between uP and PL, uP and pl, and PL and pl were 34.3%, 28.6%, and 54.3%, respectively. In the uP and PL group, the percentage of interstitial changes significantly increased (P=0.006) and that of emphysematous changes significantly decreased (P=0.023) in patients with overestimated pleural invasion. The percentage of pleural irregularities around the tumor on chest CT scan tended to increase in patients with overestimated pleural invasion and interstitial changes (P=0.066) compared to that in patients with concordant findings and interstitial changes. In the uP and pl group, the percentage of tumors in the apex of the lung significantly increased (P=0.022) in patients with underestimated pleural invasion. In the uP2 and pl group, the percentage of tumors located near the diaphragm significantly increased (P=0.024) in patients with overestimated pleural invasion.Conclusion: Interstitial changes, tumors in the apex of the lung, and those located near the diaphragm can affect the assessment of pleural invasion using chest ultrasound.