The application of breathing control for treatment of lung cancer with CHARTWEL

It is hypothesized that the poor results of treating non-small cell lung cancer with radiation therapy using conventional fractionation scheme of 1.8 2.0 Gy per fraction, 5 daily fractions per week is due, in part, to tumor progression and/or repair outpacing the injury inflicted by radiation. It has been observed that, even at the escalated dose levels of 84, 92, and 100 Gy, local failures still occur. Departing from conventional fractionation, the regime of Continuous Accelerated Hyperfractionated Radiation Therapy (CHART) was proposed by investigators at the Mount Vernon Hospital Gray Laboratory (UK), to deliver as much dose, and as quickly as possible to treat non-small cell lung cancer. The need to improve local tumor control and to reduce the incidence of distant metastasis using CHART may be achieved by dose escalation and addition of chemotherapy. In addition, to make the procedure more palatable for centers that found treatment on weekends prohibitive, the CHARTWEL (CHART Week End Less) regime was developed. Total dose was escalated to 60 Gy delivered over 18 days, allowing breaks for weekends. A two-phase technique was again used. Phase 1 was treated to 37.5 Gy and Phase 2 to 22.5 Gy. Normal tissue tolerances were the same as for CHART. For 64 patients with locally advanced non-small cell lung cancer treated with CHARTWEL, acute dysphagia was more severe but there was no late damage. After 6 months there was a higher incidence of mild pulmonary toxicity