BETA CAROTENE CHEMOPREVENTION OF HEAD AND NECK CANCER

已接受早期癌症治愈性治疗的患者， 口腔、咽和喉有极高的风险， 发展第二种癌症。 这些第二种癌症包括新的原发性癌症， 肿瘤，发生率约为4%，每年，以及复发 肿瘤的 新的原发性肿瘤通常发生在口腔，咽， 喉、食管或肺，并且是现场癌变的结果 上呼吸消化道的整个粘膜表面。 总体而言， 由于第二原发肿瘤和局部复发导致治疗失败 大约35%的I/II期患者在随访5年后发生- 起来 这种特殊的风险是一个重要的癌症控制问题， 可以通过适当的干预来改变。 证据 流行病学研究、临床研究和动物肿瘤模型表明， 补充β-胡萝卜素可能会抑制第二个 癌症在这个患者群体中。 因此，我们建议继续 招募患者参加随机、双盲、安慰剂对照试验 为了检验主要假设，每日给予50 mg β- 胡萝卜素会降低第二种癌症的发病率。 这场审判开始于 1991年入组患者，共入组168例，随机分组149例 1993年9月，患者。 我们建议共招聘480名 在两个研究中心额外招募两年的患者，然后 至少再追踪三年 研究 人群由最近诊断为鳞状细胞癌的患者组成 整个康涅狄格州的口腔、咽或喉癌， 南佛罗里达。 在治愈性治疗后，符合条件的阶段患者 I/II类疾病患者被邀请参加研究。 经过短暂的 在安慰剂导入期，受试者随机接受β-胡萝卜素或 安慰剂作为每日补充剂。 患者通过他们的 常规医生，终点为局部复发或 在口腔、咽、喉中发生第二原发癌， 食道或肺。 该项目还有以下次要目标： (a)来检测这些病人是否会服用并耐受 （B）在一段时间内每天补充β-胡萝卜素; 更正式地在参与者分组中遵守， 微电子监测，其中标准药瓶配有 一种瓶盖，包含一个微处理器，记录每个瓶子的打开， 关闭作为一个假定的剂量，和（c）获得前瞻性的数据， 确定第二原发性肿瘤的风险是否取决于年龄， 性别、初始癌症部位、治疗（放疗与手术） 最初的癌症，饮食，以及是否存在持续的 烟草和酒精暴露。

Patients who have been curatively treated for early stage cancers of the oral cavity, pharynx, and larynx have an exceptionally high risk for developing second cancers. These second cancers include new primary tumors, which occur at a rate of about 4% per year, as well as recurrent tumors. New primary tumors generally occur in the oral cavity, pharynx, larynx, esophagus, or lung, and are a consequence of field cancerization of the entire mucosal surface of the upper aerodigestive tract. Overall, treatment failure due to second primary tumors and local recurrences occurs in approximately 35% of Stage I/II patients five years of follow- up. This exceptional risk is a significant cancer control problem which potentially could be modified by appropriate interventions. Evidence from epidemiologic studies, clinical studies and animal tumor models suggests that supplemental beta-carotene may inhibit the development of second cancers in this patient population. Consequently, we propose to continue to recruit patients to a randomized, double-blind placebo-controlled trial to test the primary hypothesis that daily administration of 50 mg beta- carotene will lower the incidence of second cancers. This trial began enrolling patients in 1991, and has enrolled 168 and randomized 149 patients as of September 1993. We propose to recruit a total of 480 patients with two additional years of recruitment at two sites, and then follow the subjects for at least an additional three years. The study population consists of patients with recently diagnosed squamous cell carcinoma of the oral cavity, pharynx or larynx throughout Connecticut and South Florida. Following curative treatment, eligible patients with Stage I/II disease are invited to participate in the study. After a brief placebo run-in period, subjects are randomized to receive beta-carotene or placebo as a daily supplement. Patients are followed for disease by their regular physician with the endpoint being local recurrence or the occurrence of a second primary cancer in the oral cavity, pharynx, larynx, esophagus or lung. This project also has the following secondary aims: (a) to examine whether this patient population will take and tolerate daily supplements of beta-carotene over a period of years; (b) to assess compliance more formally in a sub-group of participants by using microelectronic monitoring, where standard pill bottles are fitted with a cap that contains a microprocessor that records each bottle opening and closing as a presumptive dose, and (c) to obtain prospective data to determine whether the risk for second primary tumors depends upon age or gender, site of the initial cancer, treatment (irradiation versus surgery) of the initial cancer, diet, and the presence or absence of continuing tobacco and alcohol exposures.