Three dimensional conformal radiotherapy for non-small cell lung carcinoma based on CT simulation in different respiratory phases in patients aged 70 years and over / 中华老年医学杂志

ABSTRACT

Objective To evaluate the application of three dimensional conformal radiotherapy (3D-CRT) for non-small cell lung carcinoma (NSCLC) based on CT simulation in different respiratory phases in patients gaed≥70 years. Methods A total of 51 patients gaed≥70 years (range 70-88 years, mean age 73.5 years) with NSCLC were treated by 3D-CRT alone, using CT images of different respiratory phases. The case numbers at Ⅰb, Ⅱb, Ⅲa, Ⅲb and Ⅳstage were 3, 7, 19, 17 and 5, respectively. Both gross tumor volumes (GTV) at the end of inspiration and expiration were fused to a total GTV which was close to motorial range of tumor in respiration, and the expansion of clinical target volume/ planning target volume (CTV/PTV) need not include respiratory motion moreover. Compared with plans of classic 3D-CRT, the efficacy, prognostic factors and side effect of this treatment were evaluated. Results Compared with the traditional expansion of CTV/PTV, the volumes of PTV in this scheme were averagely 19.3% lower (median, 17.5%),and the volumes of lung that received equal dose to tumor were averagely 21.8% lower (median, 19.9%). The 1-, 2-and 3-years total survival rates were 70. 6%, 54.9% and 29.4% with a overall tumor response rate of 78.4%. KPS scores and node stages were independent prognostic factors, age was not. Conclusions CT simulations in different respiratory phases can effectively reduce PTV and improve the life quality without affecting the therapeutic effect in senile patients with NSCLC, and can be well tolerated.