Cavity of Primary Lung Cancer

過去10年間に経験した空洞を有する原発性肺癌23例を,扁平上皮癌の15例,腺癌の5例,未分化癌の3例に分けて,臨床像とレントゲン像の特徴につき検討を加えた.扁平上皮癌の2/3と未分化癌の全例は,空洞が大きく,その大部分に炎症の合併が考えられた.すなわちこれらの組織型の肺癌では長径4cm以上の空洞が多く,乏血性壊死に感染も加わって空洞が形成される可能性が考えられた.これに対し,腺癌は大きさが4cm以下でも空洞を形成することが多く,乏血性壊死による因子が主因と考えられた.Characteristics of clinical and radiological findings of primary lung cancer with cavity were studied on 23 cases admitted to our clinic in the past 10 years. Incidence was higher in the fifth and sixth decades and more common in male than female (2.3 : I ). Histological types of these 23 cases were squamous cell carcinoma ( 1 5 cases), adenocarcinoma (5 cases) and undifferentiated carcinoma (3 cases). The mechanism of cavity formation seemed to be different among these histological types of lung cancer. The size of cavity was over 4 cm in diameter in 10 out of 1 5 cases of squamous cell carcinoma and one half of the cases had distinct clinical and laboratorical evidences of concomitant infection. Contrarily, no such inflammatory findings were seen in the other 5 cases of squamous cell carcinoma where tumor was under 4 cm in diameter. A11 of the 3 cases of undifferentiated carcinoma (tumor was over 8 cm in 2 cases and 4 cm in I case in diameter) showed definite evidence of inflammation. These findings indicated a possible mechanism of cavity formation in these two histological types of lung cancer, that necrosis would occur in consequence of ischemic changes which would appear when the size of tumor became larger than 4 cm in diameter, and in addition to this, infection of the part would accelerate the formation of the cavity. On the other hand, the cavity was observed in all cases of adenocarcinoma in spite of the size of tumor being about 4 cm in diameter or less: From these histological findings, it was thought that the main factor of cavity formation in this type of lung cancer would be the ischemic necrosis in the tumor