TUMOR KINETICS IN HEAD AND NECK CANCER

有新的临床和实验室证据，其中大部分是在 头颈部癌，即肿瘤克隆性增殖 放射治疗过程中的细胞损害了局部控制，是一个重要的 肿瘤治疗耐药的机制。最近的研究表明 用这些药物治疗前肿瘤潜能倍增时间 治疗中的增殖率。因此，有可能一个 对潜在倍增时间的前处理测定可以预测 给定的肿瘤在治疗期间重新繁殖的能力。这个，那么， 将允许为此选择加速放射治疗 具有高增殖潜力的肿瘤亚群，留下更好的 耐受性较低的肿瘤的常规分割方案 核扩散速度。这项研究的主要目的是确定 是否了解治疗前肿瘤潜能倍增时间 将允许选择最有可能受益的患者子集 从改变的分馏时间表。 对溴脱氧尿苷/延迟活组织检查技术的改进将 用于测定人头肿瘤的前处理动力学 还有脖子。细胞动力学参数将包括DNA标记 DNA合成期的指数、长度和潜在倍增 时间到了。次要参数将包括DNA指数和S阶段 分数。研究的患者群体将来自RTOG方案 90-03，一项随机试验，总应计目标为648名患者 相比之下，两个加速的，一个是常规的，一个是 Ⅲ、Ⅲ期患者超分割放射治疗方案探讨 头颈部的IV级鳞状细胞癌。两者之间的相关性 前处理动力学和局部区域控制和存活率 调查过了。分馏计划对这些指标的影响 相关性也将被研究。

There is emerging clinical and laboratory evidence, much of it in cancers of the head and neck, that proliferation of tumor clonogenic cells during radiotherapy impairs local control and is an important mechanism of tumor therapeutic resistance. Recent studies have linked the pretreatment tumor potential doubling time with these intra-treatment proliferation rates. Thus, it is possible that a pretreatment determination of the potential doubling time might predict a given tumor's ability to repopulate during treatment. This, then, would allow selection of an accelerated course of radiotherapy for that subset of tumors with a high proliferative potential, leaving better tolerated, conventional fractionation schemes for tumors with lower proliferation rates. This study's primary purpose is to determine whether knowledge of the pretreatment tumor potential doubling time will allow selection of a subset of patients most likely to benefit from altered fractionation schedules. Modifications of the bromodeoxyuridine/delayed-biopsy technique will be used to determine pretreatment kinetics in human tumors of the head and neck. Cell kinetic parameters will include the DNA labelling index, length of the DNA synthetic phase and the potential doubling time. Secondary parameters will include the DNA index and S phase fraction. The patient population studied will be from RTOG protocol 90-03, a randomized trial with a total accrual goal of 648 patients that compares two accelerated, one conventional and one hyperfractionated radiotherapy schedule in patients with stage Ill and IV squamous cell carcinoma of the head and neck. Correlations between pretreatment kinetics and localregional control and survival will be investigated. The impact of fractionation schedule upon these correlations will also be studied.