目的：本研究在報告6位B型肝炎帶原者及同時罹患胃癌病人在接受術後輔助或全程合併放射化學治療後產生第三或四級肝臟毒性的臨床及劑量學數據。材料與方法：1993年12月至2001年7月間，82位經切片證實為胃腺癌病人接受手術後輔助或全程合併放射化學治療，其中10位病人經血清學檢查為B型肝炎帶原者，10位中的6位病人在接受手術後輔助或全程合併放射化學治療後產生第三或四級肝臟毒性，為本研究的主要對象。5位病人接受45Gy／1.8Gy／25次，1位病人接受50.4Gy／1.8Gy／28次的18 MV光子射束體外放射治療於腫瘤切除區域及附近淋巴區域。同步合併化學治療使用每週1次靜脈連續注射24小時的5-fluorouracil 2 gm/m2及leucovorin 300 mg/m2，共接受3-6療程（中位數：5療程），3位病人另接受1次放射治療療程開始前3週的etoposide，5-fluorouracil，leucovorin前導化學治療。第三或第四級肝臟毒性根據美國國家癌症中心之常見毒性標準定義為非惡性腹水形成及鹼性磷酸鋂上昇2倍以上，或肝指數（GOT/GPT）上升至正常值上限或治療前的5倍以上。病人完成治療接受每月1次的身體檢查及血液血球計數與生化檢查。劑量體積圖使用於正常器官劑量參數的分析工具。結果：6位病人放射治療後中位數38天發生第三或第四級肝臟毒性，5位病人完全康復，1位病人死於此併發症。5位病人病發時有血清學或病理學的慢性肝炎急性發作證據。合併放射化學治療療程中的最大血液系統毒性為第1級1位，第2級4位，第3級l位病人。6位病人的平均肝臟劑量範圍為10.4Gy到22.9Gy（平均數17.2Gy），肝臟接受超過30Gy劑量的體積比例範圍為7%到37%（平均數24%），平均的正常組織併發症機率為3.3%，範圍為0.03%到6.8%，這三項參數的平均數顯著低於另外12位肝癌病人接受三度空間順形放射治療後發生放射線引起之肝臟病變的劑量參數平均數。結論： B型肝炎帶原者罹患胃癌接受合併放射化學治療後發生肝臟毒性的現象，是文獻上少見且值得特別注意的。在給予化學治療的同時，肝臟對放射線的忍受度更形下降。進一步對肝臟傷害形成機轉的研究是急切需要的。

Purpose: This study is to report the clinical and dosimetric parameters of six patients who were carriers of type B chronic hepatitis and developed grade 3 or 4 hepatic toxicity after adjuvant or definitive concurrent chemoirradiation for gastric cancer. Materials and Methods: From December 1993 through July 2001, 82 patients with gastric adenocarcinoma underwent radiotherapy as adjuvant or definitive treatment. Ten patients were carriers of type B chronic hepatitis on serology test. Six of 10 patients who developed grade 3 or 4 hepatic toxicity within 4 months after radiotherapy, formed the basis of this study. Five patients underwent external-beam radiotherapy with 45 Gy/1.8 Gy/25 fractions and 18 MV photons delivered to the tumor bed and regional lymphatics Over 5 weeks. One patient had the radiotherapy with 50.4 Gy/28 fractions. Concurrent chemotherapy consisted of 3-6 (median: 5) weekly cycles of intravenous infusion with 5fluorouracil 2 gm/m2 and leucovorin 300mg/m2 for 24 hours. Dose-volume histograms of the critical organs were used for the dosimetric factors in these patients. Results: Six patients developed grade 3 or 4 hepatic toxicity, with a median interval of 38 days from completion of radiotherapy. One patient died of this complication and five patients recovered. All but one patient had either serologic or histological evidence of reactivation of chronic viral hepatitis. Mean dose of liver of the 6 patients ranged from 10.4 Gy to 22.9 Gy (mean: 17.2 Gy), while the percent volume receiving more than 30 Gy of radiation (V3o Gy) ranged from 7% to 37% (mean: 24%). Mean normal tissue complication probability (NTCP) was 3.3%, ranging from 0.03% to 6.8%. Mean hepatic dose, V30GY, and NTCP were all significantly lower than those of the 12 patients with hepatocelular carcinoma and radiation-induced liver disease after three-dimensional conformal radiotherapy. Conclusion: Hepatic toxicity after concurrent chemoirradiation, in patients who were carriers of type B chronic hepatitis and underwent treatment for gastric cancer, deserves special attention and was rarely reported in the literature. The tolerance of liver to radiation was even lower than expected in the presence of concurrent chemotherapy.