Resistance to Cisplatin Renders High Metastatic Potential in Human Non-Small Cell Lung Cancer Cell Line / 대한흉부외과학회지

BACKGROUND: Resistance to cytotoxic drugs such as cisplatin is an important cause of treatment failure in lung cancer. The mechanisms are omplex and have yet to be clearly elucidated, but the acquisition of drug resistance possibly has resulted in poor survival. The purpose of the study is to evaluate whether the resistant tumor cells would gain more potential for metastasis. MATERIAL AND METHOD: we examined the metastatic potential of a cisplatin-reisistant cell line, H460/CIS, which was established from the human lung cancer cell line H460 by in vitro selection with gradually increased concentration of cisplatin. The parental cisplatin-sensitive cell line(H460) was used as the control and analysis on the expression of angiogenesis or growth-related factors, gelatin zymographic analysis and in vivo spontaneous metastatic experiment in nude mice were done. RESULT: Increased levels of vascular endothelial growth factor(VEGF) and basic fibroblast growth factor (bFGF) were found in H460/CIS. Gelatin zymographic analyses showed that proteinase A in the culture medium of H460/CIS was processed from latent to activated form. The in vivo experiment showed that H460/CIS cells spontaneously metastasized to the lungs but parental cells did not. CONCLUSION: resistance to the chemotherapeutic agents may render the tumor aggressi-veness and metastatic potential. Therefore, the risk, rather than benefit, from inadvertent application of adj uvant or neoadj uvant chemotherapy to early-staged lung cancer should be considered.

transprosthetic Pressure Gradient after aortic Valve Replacement with Small Sized Prostheses / 대한흉부외과학회지

BACKGROUND: The prognosis after an aortic valve replacment can be affected significantly by the transprosthetic pressure gradient which is determined mainly by the size of the patients body and the prosthesis used. We analyzed the hemodynamic feature of two relatively new prosthese the ATS and the evensized Medtronic-Hall(M-H) valves by measuring the transprosthetic pressure gradient in the cases where small sizes (23mm or smaller) were used. MATERIAL AND METHOD: There were 94 patients who received whom aortic valve replacement with prosthesis smaller than 23 mm from October 1994 to June 1998. In these patients the transprosthetic pressure gradient clalculated from the pressure half time during postoperative Dopper echocardiographic examination was compared between the prostheses of different sizes. The body surface area of each patient was also taken into consideration. RESULT: The mean pressure gradient and body surface area in each group were 21.7+/-10.2 mmHg and 1.52+/-0.14m2 in ATS 19mm 11.4+/-6.5 mmHg and 1,57+/-0.20m2 in M-H 20mm 15.2+/-6.3 mmHg and 1.54+/-0.13m2 in ATS 21mm 9.3+/-2.5 mmHg and 1.63 +/-0.14m2 in M-H 22 mm and 12.9+/-5.3 mmHg and 1.69+/-0.13m2 in ATS 23mm. CONCLUSIONS: The 19mm ATS prosthesis showed significant trasprosthetic pressure gradient which is similar to the values previously reported with other bileaflet prosthesesm Close follow-up was needed in terms of exercise capacity and change in left ventiricular geometry. In patients with small aortic valve annulus the 20mm M-H valve is recomendable as an alternative to 19mm bileaflet valves because it has less pressure gradient with similar outer diameter.

Early Result of Surgical Resection after Pre-Operative Concurrent chemoradiotherapy for N2-Positive Stage IIIA NSCLC / 대한흉부외과학회지

BACKGROUND: Many recent results of clinical trials show that pre-operative concurrent chemoradiotherapy and surgical resection could increase the survival of N2 positive stage IIIA non-small cell lung cancer. This study was performed to assess the feasibility, toxicity, and affect rates of concurrent chemoradiotherapy and surgical resection in N2 positive stage IIIA non-small cell lung cancer. MATERIAL AND METHOD: Thirty-one patients who underwent preoperative concurrent chemoradiotherapy for N2 positive stage IIIA non-small-cell lung cancer from May 1997 to April 1999 were entered into the study. Mean age was 61 yrs (43-70 yrs), There were 24 men and 7 women. The confirmation of N2 disease were achieved through mediastinoscopic biopsy (24) and CT scans (7). Induction was achieved by two cycles of cisplatin and etoposide(EP) plus concurrent chest radiotherapy to 45 Gy. Resections were done at 3 weeks after the complection of preoperative concurrent chemoradiotherapy. Resections were performed in 23 patients, excluding 5 refusals and 3 distant metastasis. All patients were compled the thoracic radiotherapy except one who had distant metastasis. Twenty three patients were completed the planned 2 cycles of EP chemotherapy, and 8 patients were received only 1 cycle for severe side effects (6), refusal (1), and distant metastasis(1). There was one postoperative mortality, and the cause of death was ARDS. Three patients who had neutropenic fever and one patient who had radiation pneumonitis were required admission and treatment. Esophagitis was the most common acute side effect, but relatively well-tolerated in most patients. The complection rate of concurrent chemoradiotherapy was 74%, resection rate was 71%, pathologic complete remission rate was 13.6%, and pathologic down-staging rate was 68%. CONCLUSION: Morbidity related to each treatment was acceptable and many of the patients have benefited down staging of its disease. Further prospective, preferably randomized, clinical trials of larger scale may be warranted to confirm the actual benefit of preoperative concurrent chemoradiotherapy and surgical resection in N2-positive stage IIIA non-small cell lung cancer.

The Clamshell Incision for the Complete Repair in Pulmonary Atresia with Ventricular Septal Defect , and Major Aortopulmonary Collaterals / 대한흉부외과학회지

A 6-month old girl who had pulmonary atresia with ventricular septal defect and major aortopulmonary collaterals underwent one-stage complete repair with unifocalization through a bilateral thoracosternotomy(clamshell incision). There were no serious postoperative compli cations, and the postoperative echocardio-graphy showed no residual ventricular septal defect or significant pulmonary artery stenosis. In this condition, great surgical variability exists regarding the sources of pulmonary blood flow. Recent clinical work has focused on a one-stage complete repair. The potential advantages of the clamshell incision are apparent in terms of mediastinal approach, postoperative results, and safety.