Clinical Study Of Pneumonitis After Combined Therapy Of Chemotherapy And 3D-CRT For Lung Cancer

Lung cancer is one of the most common tumor .It is serious threaten the health of human being with high incidence and mortality rate. In the dead cases of patient with cancer, the percentage of lung cancer is 17.8%, it is the first cause of dead cancer patients. Operation is the best choose of most lung cancer. But the patients who are suitable for operation only count for 20-30%. The percentage between 70-80% of the patients with lung cancer is unsuitable for operation due to advanced stage, who have to choose the non-operation treatment. The radiotherapy and chemotherapy is the main methods of non-operation treatment. Whatever the non-small cell lung cancer (NSCLC) or small cell lung cancer (SCLC), it has get certain progress with combine the radiotherapy and chemotherapy. Meantime, it also piles up the side effects. Radiation pneumonitis is a serious and common syndrome in patients with the radiotherapy and chemotherapy. Radiation pneumonitis is a kind of radiation-induced lung injury which cause the normal lung tissue injury by the certain radiation dose. In the compositive theatment of lungcancer .the side effects of the radiotherapy and chemotherapy will complex and enlarge the radiation-induced lung injury. Radiation pneumonitis limits the dose of the radiotherapy. It not only affect the effects of radiotherapy also the life quality of patient. The 3-dimension conformal radiotherapy (3D-CRT) is a breakthrough of radiotherapy technology. It's accurate physical dose distribution and the sharp decline of dose of the outside target volume which can effective reduce the radiation dose of the normal lung tissues of the outside target volume, and reduce the incidence rate of radiation pneumonitis. It has a lot of factors of radiation pneumonitis. The past studies are mainly limited to common radiotherapy technology and the results are different. We try to analyze the factor and the effects of radiation pneumonitis and the combination of chemotherapy and 3D-CRT. Objects: To analyze the factors, diagnoses and the treatments of radiation pneumonitis in lung cancer treatments with chemotherapy and 3D-CRT. Materials and Methods: the 81 patients of lung cancer who had accepted treatments in Feb. 2002 to Oct. 2004, were chosen to review analysis .All 81 cases had accepted the chemotherapy and 3D-CRT.Try to analyze the factors, diagnoses and the treatments of radiation pneumonitis. The factors were observed include sex, age, KPS, weigh lost, history of smoking, pathology and stages. The radiation factors includes radiation volumes, radiation dose, average radiation dose, radiation part of tumor. The chemotherapy factors includes concurrent or non concurrent chemotherapy, if or not has TAXOL. To evaluate the distribution differences of all factors of 2 termsby x1 test- To evaluate the risk ratio of all causes which can lead to radiation pneumonitis by logistic regression. All data processed by SAS 8.2. Study the efficient rate and prognosis, The diagnosis methods are the combination of symptoms and radiographic evidences. To stages by "RTOG acute radiation pneumonitis and lung injury stage standards ". Results: there are 32 cases suffered the radiation pneumonitis in 81 cases with chemotherapy and 3D-CRT. The incidence rate is 39.5% (32/81). it often occurred 1-4 months after radiotherapy. The 1,2,3,4,5 stages of radiation pneumonitis are 53%(17/32), 15.6%(5/32), 12.5%(4/32), 9%(3/32), 9%(3/32) respectively. The factors analyzed by one-way analysis, sex: OR 1.74 (P=0.06), age: ^50 years old OR 1.0, 51-59OR 2.11 (p-0.66), ^60 OR 3.12 (P=0.034) KPS: ^60 OR 0.69(p=0.032) , weight loss: OR 2.25 (p=0.056). smoker: OR 1.25 (p=0.506) NSCLC: OR 0.36 (p=0.048). IV stage: OR 1.125 (p=0.088). PTV(cm3):^300 OR 1.95 (p=0.015). tumor dose(Gy): ^65 OR 1.89 (p=0.02); V20(%): >32 OR 1.33 (p=0.43) Lung average dose (Gy): <20 OR 1.0, 21-25 OR 0.88 (p=0.81); >25 OR 1.667 (p=0.162). tumor position: middle lung,OR 1.75 (p=0.12); lower lung OR 1.30 (p=0.533). concurrent chemotherapy: OR 1.91 (p=0.04); TAXOL: OR 2.25 (p=0.056). Multi-ways analysis: SCLC OR 37.32 (p=0.002). non smoking OR 7.76 (p<0.001 non-concurrent chemotherapy: OR 0.12 (p=0.002). There are 24 cases with pneumonitis had accepted the treatment. 16 of them became better, 3 of them had no change, 5 of them had dead.Conclusion: one-way analysis suggests that the age, KPS , pathology, radiotherapy volume, tumor dose and concurrent chemotherapy have related to radiation pneumonitis. The statistic shows significant difference. Multi-ways analysis suggests that SCLC, history of non-smoking, non-concurrent chemotherapy are the independent factors to the occur of radiation pneumonitis. The risk of pneumonitis for lung cancer patients of small cell or non smoking history is high; The risk of pneumonitis for lung cancer patients of non concurrent chemotherapy is low. 3 >. In the diagnosis of pneumonitis, both of the symptom and radiographic evidence should be taken into account. 4^ Most of the pneumonitis patients get better with syptom after treatment in this group.