Carbon Ion Radiotherapy for Lymph Node Recurrence

Purpose/Objective(s): To evaluate the effectiveness and usefulness ofcarbon ion radiation therapy (CIRT) in patients with lymph node recur-rence, we analyzed our treatment results with various primary sites. \nMaterials/Methods: Patient's eligibility of CIRT for lymph node recur-rence in principle were, 1) lymph node recurrence after primary treatment,2) no other metastasis has been observed, 3) ECOG PS 0-2, 4) at least 5-mm gap between the recurrent lesion and radiosensitive organs, includinggastrointestinal tract and bladder, and 5) Irradiated field not exceeding 15cm. In some cases, Gore-Tex made spacer had been inserted surgicallybefore CIRT to make a gap between surrounding radiosensitive tissue. AsCIRT technique, all sites were irradiated using 3-D conformal planningsystem with 2 to 4 portals, with respiratory gating if necessary. In targetdelineation, involved node was defined as GTV, prophylactic lymph nodearea was defined as CTV, and CTV + 5 mm (excluding GI) was defined as PTV. Treatment was performed 4 times a week, up to a total dose of 48GyE / 12 fractions / 3 weeks in principle. \nResults: From December 1996 to February 2012, 189 cases with 233 siteswere treated. Patient' age ranged from 32 to 87 with a median of 65, with141 males and 92 females. The primary sites were lung in 68, rectum in 44,pancreas in 12, uterine cervix and body in 11, colon in 8, stomach and esophagus in 5, renal pelvis in 4 and others in 21. The tumors were histologically classified as follows: 160 with adenocarcinoma, 37 squa-mous cell carcinoma, 12 with transitional cell carcinoma, and 24 with others. The sites of recurrent lymph nodes were 92 in chest, 69 in abdomen, 59 in pelvis and 13 in neck. The radiation doses were 30-38.4GyE in 10, 40-45.6GyE in 18, 48GyE in 106, 50.2-57.6GyE in 84, 60- 64GyE in 9 and 70.4-73.6GyE in 6 cases. Among them, 23 sites were previously irradiated. The follow up period ranged from 1 month to 9 years7 months with a median of 1 year 6 months. No acute grade 3 or higheradverse toxicities have been observed. Late adverse events were observed in 1 case, who developed duodenum bleeding at re-irradiate site. Tumorprogressions were recognized at irradiated sites in 18 (8%), regional in 34(15%), whereas distant sites in 128 (55%). At the time of analysis. 115 patients had died, including 99 of the malignancies and 16 of intercurrent diseases. Survival rates were calculated at 204 sites followed for more than6 months from the completion of the treatment or followed to the death. The overall survival rates of entire group were 77.3% in 1 year, 52.8% in 2year, 42.5% in 3 year and 29.0% in 4 year, respectively (median survivaltime: 2 year and 2 months). The overall 2 year survival rates of lung and rectal cancer were 45.4% and 42.6%, respectively. \nConclusions: CIRT for lymph node recurrence from various malignanciesmight be promising to have favorable local control with acceptable toxicities, although not affecting to reduce distant metastases.
ASTRO's 54th Annual Meeting