Intercalated radio-chemotherapy in small cell lung cancer: toxicity and implications for future regimens.

Thirty-six patients with small cell lung cancer have been treated using chemotherapy comprising carboplatin, ifosphamide and etoposide. A total of six cycles of chemotherapy were given. In 15 patients with limited disease intercalated radio-chemotherapy was used in which two 5-day courses of hyperfractionated radiotherapy were given to the thorax after the first and second cycles of chemotherapy. Each course of thoracic radiotherapy delivered 15 Gy in 15 fractions over 5 days. Oesophagitis occurred in 7 patients (40%), in 5 of whom this was severe (WHO grade 3). Radiological pneumonitis developed in 6 patients (40%) with subsequent fibrosis in 2 patients. These effects are greater than would be expected with this dose of radiation alone and reflect marked enhancement of normal tissue toxicity.