PRIMARY PERIPHERAL LUNG-CARCINOMA SMALLER THAN 1 CM IN DIAMETER

Background: Several investigators have reported on the risk of limited resection in patients with small peripheral lung cancer. Primary peri pheral lung carcinomas 1 cm or less in maximum dimension were reviewed to study the feasibility of limited surgery, Methods: Among 1,051 lun g cancer patients who underwent surgical resection of the lung in the National Cancer Center Hospital East, Kashiwa, Chiba, Japan, from Janu ary 1986 through March 1997, there were 13 patients who had untreated peripheral cN0M0 tumors 1 cm or less in maximum dimension on the resec ted specimens who underwent systematic mediastinal dissection. Their s pecimens were histopathologically reviewed. Results: There were ten ad enocarcinomas, one small cell carcinoma, one poorly differentiated squ amous cell carcinoma, and one typical carcinoid tumor. One adenocarcin oma showed lymphatic vessel invasion, venous invasion, and a subcarina l node metastasis. The small cell carcinoma was accompanied by a lymph node metastasis in a segmental node, The small cell carcinoma and ano ther adenocarcinoma showed lymphatic vessel invasion, Of the ten adeno carcinomas, six were Noguchi's type B and four were type C. Conclusion : Even among the pulmonary peripheral cancers smaller than 1 cm in dia meter, more than one third showed an invasive nature, This fact must b e considered in selecting limited resection in these patients. It is e vident that tumor size alone cannot be an indicator for limited resect ion in lung cancer patients.