Application of simplified intensity modulated radiation therapy in gastric cancer after operation / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To elucidate the application and the dosimetry characteristic of the simplified intensity modulated radiation therapy (sIMRT) for gastric cancer after operation, and to compare the dose distribution with intensity modulated radiation therapy (IMRT) and three-dimension conformal radiation therapy (3D-CRT).</p><p><b>METHODS</b>Twelve patients with gastric cancer after operation were enrolled in this study. 3D-CRT plan, 5-field IMRT plans (20 degree, 80 degree, 180 degree, 280 degree, 340 degree) and 5-field sIMRT plans (20 degree, 80 degree, 180 degree, 280 degree, 340 degree) were performed for each patient. The conformal index (CI), heterogeneity index (HI) of the planning target volume (PTV) and the dose of normal organs were analyzed with the dose volume histogram (DVH). The total MU and treatment time were also compared.</p><p><b>RESULTS</b>The sIMRT and IMRT plans had comparable CI (sIMRT>IMRT>3D-CRT), and showed better dose conformity but worse homogeneity than 3D-CRT. The percentage of volume receiving 20 Gy, 25 Gy, 30 Gy and 40 Gy by liver were significantly lower in sIMRT than that in 3D-CRT, and comparable to IMRT. All the dose volumes to kidneys with sIMRT were still significantly lower as compared to 3D-CRT, and comparable to IMRT. The sIMRT plan was better than IMRT plan in total MU and treatment time.</p><p><b>CONCLUSIONS</b>sIMRT has comparable dose distribution in patients with gastric cancer to IMRT, but is significantly better than 3D-CRT. Treatment time of sIMRT is the shortest. So sIMRT technique can be applied more simply.</p>

A randomized controlled trial of intensity-modulated radiation therapy plus docetaxel and cisplatin versus simple intensity-modulated radiation therapy in II-III stage esophageal carcinoma / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To compare the efficacy and toxicity of intensity- modulated radiation therapy plus chemotherapy (IMRT-TP) with simple intensity-modulated radiation therapy (IMRT) in the treatment of locally advanced esophageal carcinoma.</p><p><b>METHODS</b>A total of 170 eligible patients with locally advanced esophageal carcinoma were recruited prospectively from September 2004 to April 2008 and randomly divided into IMRT-TP group and IMRT group. Two groups were treated with IMRT of 6MV-X. The radiation dose was 60 Gy in 30 fractions in IMRT-TP group and 66 Gy in 30 fractions in IMRT group. The regimen of chemotherapy consisted of docetaxel and cisplatin in IMRT-TP group for 2 cycles.</p><p><b>RESULTS</b>Of 170 patients, 160 completed the trial, including 75 patients of IMRT-TP group and 85 of IMRT group. As compared to IMRT group, total recurrence rate [69.3% (52/75) vs. 84.7% (72/85), P=0.020] and local recurrence rate [50.7% (38/75) vs. 67.1% (57/85), P=0.035] decreased in IMRT-TP group, the 5-year overall survival (29.3% vs. 15.3%, P=0.031) and 5-year recurrence free survival (24.0% vs. 10.6%, P=0.015) increased in IMRT-TP group. While severe side effect ratio increased obviously in IMRT-TP group [54.7% (41/75) vs. 4.7% (4/85), P=0.000].</p><p><b>CONCLUSION</b>As compare to simple IMRT, IMRT plus docetaxel and cisplatin can decrease the local recurrence rate, prolong the overall survival and regression-free survival, but bring more side effects.</p>