Hirozo Sakaguchi

Micrometastasis to lymph nodes in stage I left lung cancer patients

BACKGROUND To evaluate the frequency and clinicopathological characteristics of lymph node micrometastasis in left lung cancer patients diagnosed to be stage IA and IB based on routine histopathologic examinations, we examined the lymph nodes in patients who had undergone an extended mediastinal lymphadenectomy, using immunohistochemical methods. METHODS Paraffin-embedded tissue sections from the lymph nodes in 49 patients with stage I left lung cancers were studied. We used AE1/AE3 as the anticytokeratin and Ber-EP4 as the antiepithelial cell antibodies when performing immunohistochemical staining. RESULTS We identified micrometastasis of the lymph nodes in 13 (26.5%) of 49 patients with stage I left lung cancer. NO disease was reclassified as N1 disease in 5 cases, N2 disease in 6 cases, and N3 disease in 2 cases. The location of the micrometastatic lymph nodes proved to be wide regions including the contralateral and highest mediastinal nodes, and 6 (46.2%) out of the 13 patients with micrometastasis were thus presumed not to be completely eliminated by a standard lymphadenectomy through an ipsilateral thoracotomy. The five year survival rate of patients with reclassified N1 to N3 disease was 74%, and the presence of micrometastasis was found to have no significant effect on the outcomes. CONCLUSIONS The micrometastatic involvement of the lymph nodes was both more frequent and extensive than expected even in stage I left lung cancer. These results suggest that an extended mediastinal lymphadenectomy may therefore be required for the locoregional control of stage I left lung cancer patients.

Postoperative empyema following lung cancer surgery

Postoperative empyema following lung cancer surgery is a serious complication. Occurrence rate of postoperative empyema following lung cancer surgery, patient background, surgical procedures, date of empyema onset, treatment, and prognosis of 4772 patients who underwent lung cancer surgery between 2008 and 2012 were investigated. Postoperative empyema following lung cancer surgery was found in 43 patients (0.9%). The occurrence rate of postoperative empyema was significantly higher in patients with the following factors: male gender, extended surgery such as pneumonectomy, bi-lobectomy and thoracotomy, squamous cell carcinoma, and an advanced pathologic stage of II and above. Chest drainage, video-assisted thoracic surgery debridement, fenestration, and thoracoplasy were performed, where 29 patients were cured (67.5%) and 5 patients (11.6%) died from thoracic empyema-related complications. Nine patients were not cured and died due to cancer or other diseases during treatment. When comparing cured and non-cured patients, it is indicated that squamous cell carcinoma, administration of steroids, history of interstitial pneumonia, presence of bronchial stump fistula, exacerbation of interstitial pneumonia and presence of non-fermenting Gram-negative bacilli led to a significantly low prognosis. The five-year overall survival rate was 34.9%.