BETA CAROTENE CHEMOPREVENTION OF HEAD AND NECK CANCER

曾接受根治性治疗的早期癌症患者 口腔、咽部和喉部有极高的患病风险。 患上第二种癌症。这些第二种癌症包括新的原发癌症 肿瘤，以每年约4%的速度发生，以及复发 肿瘤。新的原发肿瘤通常发生在口腔、咽部、 喉、食道或肺，是野生性癌变的结果 上呼吸道的整个粘膜表面。总的来说， 第二原发癌和局部复发导致的治疗失败 大约35%的I/II期患者经过5年的随访- 向上。这种异常的风险是一个重大的癌症控制问题， 可能会通过适当的干预措施加以改变。证据来自 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次 这一患者群体中的癌症。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 为了检验每天服用50毫克的β- 胡萝卜素将降低第二次癌症的发生率。审判开始了 1991年招募患者，并已招募168人和随机调查149人 截至1993年9月的病人数目。我们建议总共招聘480人 患者在两个地点额外招募两年，然后 至少再跟随受试者三年。这项研究 人群由最近诊断为鳞状细胞的患者组成 遍及康涅狄格州的口腔、咽或喉癌 佛罗里达州南部。经过根治治疗，符合条件的患者分期 I/II疾病被邀请参加这项研究。在简短的发言后 在安慰剂磨合期，受试者被随机接受β-胡萝卜素或 安慰剂作为每日补充剂。病人患了病之后，他们的 终点为局部复发或 第二原发癌发生在口腔、咽、喉、 食道或肺。该项目还有以下次要目标： (A)检查这一患者群体是否能够承受和耐受 在一段时间内每日补充β-胡萝卜素；(B)评估 在参与者的子组中更正式地通过使用 微电子监测，其中标准的药瓶安装有一个 一个包含微处理器的盖子，该处理器记录每个瓶子的打开和 作为推定剂量关闭，以及(C)获得预期数据 确定第二原发癌的风险是否取决于年龄或 性别、最初癌症的部位、治疗(放疗与手术) 最初的癌症，饮食，以及是否有持续的 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.