Comparison of intensity‐modulated radiotherapy and 3‐dimensional conformal radiotherapy as adjuvant therapy for gastric cancer

Abstract

BACKGROUND:The current study was performed to compare the clinical outcomes and toxicity in patients treated with postoperative chemoradiotherapy for gastric cancer using intensity-modulated radiotherapy (IMRT) versus 3-dimensional conformal radiotherapy (3D CRT). METHODS: Fifty-seven patients with gastric or gastroesophageal junction cancer were treated postoperatively: 26 with 3D CRT and 31 with IMRT. Concurrent chemotherapy was capecitabine (n ¼ 31), 5-fluorouracil (5-FU) (n ¼ 25), or none (n ¼ 1). The median radiation dose was 45 Gy. Dose volume histogram parameters for kidney and liver were compared between treatment groups. RESULTS: The 2-year overall survival rates for 3D CRT versus IMRT were 51% and 65%, respectively (P ¼ .5). Four locoregional failures occurred each in the 3D CRT (15%) and the IMRT (13%) patients. Grade 2 acute gastrointestinal toxicity was found to be similar between the 3D CRT and IMRT patients (61.5% vs 61.2%, respectively) but more treatment breaks were needed (3 vs 0, respectively). The median serum creatinine from before radiotherapy to most recent creatinine was unchanged in the IMRT group (0.80 mg/dL) but increased in the 3D CRT group from 0.80 mg/dL to 1.0 mg/dL (P ¼ .02). The median kidney mean dose was higher in the IMRT versus the 3D CRT group (13.9 Gy vs 11.1 Gy; P ¼ .05). The median kidney V20 was lower for the IMRT versus the 3D CRT group (17.5% vs 22%; P ¼ .17). The median liver mean dose for IMRT and 3D CRT was 13.6 Gy and 18.6 Gy, respectively (P ¼ .19). The median liver V30 was 16.1% and 28%, respectively (P < .001). CONCLUSIONS: Adjuvant chemoradiotherapy was well tolerated. IMRT was found to provide sparing to the liver and possibly renal function. Cancer 2010;116:3943-52.

Image-guided intensity-modulated radiotherapy for patients with locally advanced gastric cancer: a clinical feasibility study

“…Although IMRT does not provide a significant reduction in acute toxicity compared to con RT, it does spare the kidneys and liver, as demonstrated in this study as well as previous studies [11][12][13]. The sparing of critical organs is clinically very important because concurrent chemotherapy also affects the kidneys, liver, and parts of the spinal cord and because it reduces potential long-term toxicity, especially for patients undergoing major abdominal surgery and for those who may subsequently need further chemotherapy.…”

“…A previous comparison of patients treated with con RT or IMRT indicated that IMRT reduces the dose to the liver but does not reduce acute gastrointestinal toxicity [11]. This finding was supported by another study in which IMRT was also shown to provide better protection of the liver and kidneys compared with 3D CRT [12], although this conflicts with a study that showed only marginal sparing of the kidneys [13].…”

Adjuvant Treatment for Gastric Cancer: Chemotherapy Versus Radiation

“…Subsequently, consensus guidelines were published to review important anatomic issues to be considered to ensure that radiation oncologists understood the location of the intended targets [45,46]. Current studies are exploring the benefits of transcending the two-dimensional techniques used in the INT-0116 study in favor of three-dimensional conformal and intensity-modulated radiation therapy [47,48]. These techniques rely on computed tomography (CT)-based treatment planning to maximize dose to the intended regions and minimize dose to the surrounding normal tissues.…”

Phase I study of docetaxel, cisplatin and concurrent radiotherapy for locally advanced gastric adenocarcinoma

“…All patients received effective supportive care, especially nutritional support, which was very important to maintain the tolerability of the patients for the combined treatments. In the setting of definitive chemoradiotherapy, image guided 3D-CRT and IMRT are warranted to appropriately protect the critical organs around the tumor, including small intestines, kidneys, liver and the spinal cord [20]. Typically the target volumes include gross tumor, nodal regions and structures at risk of involvement.…”