ULTRARAPID HIGH-DOSE COURSE OF PROPHYLACTIC CRANIAL IRRADIATION IN SMALL-CELL LUNG-CANCER - EVALUATION OF LATE NEUROLOGIC MORBIDITY IN 16 LONG-TERM SURVIVORS

Despite the reduction in the incidence of brain metastases following p rophylactic cranial irradiation (PCI) in patients with small-cell lung cancer (SCLC), the use of this modality is still controversial due to the lack of improvement in survival and the appearance of neurotoxici ty in long-term survivors. Moreover, the optimum dose, fraction size, and timing are not known. From 1980 to 1988, 70 patients with limited stage SCLC underwent PCI after or during multimodality treatment of th eir primary tumor. Most of these patients (75.7%) received an unconven tional ultrarapid high-dose course of 17 Gy in two fractions over 3 da ys. Long-term (range 60-138 months) survivors (n = 16) were invited to have a complete neurological evaluation including computed cranial to mography (CCT), 99mTc-HMPAO single photon emission computerized tomogr aphy (SPECT) scan, electroencephalography (EEG), magnetic resonance im aging (MRI), and neuropsychometry. Delayed neurologic compli cations o r psychometric impairment was observed in 46% of patients. One or more abnormalities were detected by CCT in all patients, and the presence of neurologic complications seemed to correlate with periventricular a nd subcortical white matter changes. A strong correlation was found be tween CCT and SPECT periventricular white matter changes. Although the incidence of late neurologic toxicity following this rapid course of irradiation was high, clinical findings were less severe than expected , and all the patients were capable of self-care.