University of Adelaide, School of Chemistry and Physics, Australia.
Phys Med. 2010 Oct;26(4):177-83. doi: 10.1016/j.ejmp.2009.11.004. Epub 2010 Jan 14.
Advanced head and neck cancers are one of the most challenging cancers facing the oncologists due to their aggressiveness attributable to the high hypoxic content and the tumour's ability to repopulate during radiotherapy. Alterations of radiotherapy fractionation schedules are possible ways to improve tumour control. Clinical trials have shown that both hyperfractionated radiotherapy (multiple fractions a day, over the same treatment time), and accelerated radiotherapy (higher doses per fraction, six days a week, over 5 weeks or less) are more effective than conventional radiotherapy in the management of head and neck cancer. However, the treatment choice between hyperfractionated and accelerated radiotherapy is still debated, due to very similar results obtained regarding tumour control. Furthermore, while radiotherapy alone has an impact on the short-term prognosis of advanced head and neck cancer, the long-term benefits have been moderate. Cisplatin is a chemotherapeutic agent which combined with conventional radiotherapy has shown to improve patient survival. The present paper employs a Monte Carlo modelling approach in assessing the effect of combined cisplatin-altered fractionation schedule on tumour response. The growth of a head and neck carcinoma has been modelled using probabilistic functions sampled by computer generated random number sequences, maintaining the biological constitution of a tumour. The tumour growth model has been built to simulate the in vivo processes taking place before and after radiotherapy/chemotherapy. The model has shown that adding cisplatin to radiotherapy improves tumour control in both hyperfractionated and accelerated radiotherapy.
晚期头颈部癌症是肿瘤学家面临的最具挑战性的癌症之一，由于其侵袭性归因于高缺氧含量和肿瘤在放疗期间重新增殖的能力。改变放疗分割方案是提高肿瘤控制的可能方法。临床试验表明，超分割放疗（每天多次分割，在相同的治疗时间内）和加速放疗（每周 6 天，每天更高剂量，5 周或更短时间内）在头颈部癌症的治疗中比常规放疗更有效。然而，由于在肿瘤控制方面取得了非常相似的结果，超分割和加速放疗之间的治疗选择仍存在争议。此外，虽然单独放疗对头颈部晚期癌症的短期预后有影响，但长期获益适中。顺铂是一种化疗药物，与常规放疗联合使用已显示可提高患者生存率。本文采用蒙特卡罗建模方法评估联合顺铂改变分割方案对肿瘤反应的影响。头颈部癌的生长采用通过计算机生成的随机数序列采样的概率函数进行建模，保持肿瘤的生物学构成。肿瘤生长模型被构建为模拟放疗/化疗前后发生的体内过程。该模型表明，在超分割和加速放疗中，顺铂联合放疗可改善肿瘤控制。
