Cerebral toxicity in patients treated for small cell carcinoma of the lung

Objective: To present the clinical characteristics of patients enrolled in a trial of treatment of small cell carcinoma (SCC) of the lung and to descr ibe the central nervous system toxicity associated with the chemotherapy an d prophylactic cranial irradiation (PCI), Material and Methods: We performed a retrospective analysis of 60 patients with SCC who received chemotherapy and thoracic radiation therapy. PCI was administered to patients who had limited disease or who had extensive disea se that was subsequently down-staged to only residual chest disease after i nitial treatment. The total PCI dose was 3,200 cGy administered in 16 fract ions of 200 cGy, given concurrently with systemic chemotherapy, Diagnostic criteria for leukoencephalopathy were based on previously published guideli nes. Results: Of the 60 eligible and enrolled patients, 35 received PCI and 25 d id not. Leukoencephalopathy developed in 5 of the 35 patients (14%) who rec eived PCI, The median age of the patients in whom leukoencephalopathy devel oped was 64 years (range, 57 to 69), and the median follow-up time was 59 m onths. The most common signs and symptoms of leukoencephalopathy were intel lectual changes, memory alterations, and motor abnormalities. The mean time to onset of symptoms after termination of irradiation was 357 days (range, 30 to 524), Of all 60 patients, 6 were still alive 4 years after enrollmen t, and 3 of them (50%) already had leukoencephalopathy, Conclusion: Small dosage fractions of PCI may still result in leukoencephal opathy. The routine use of PCI in the management of SCC should be reassesse d because of increasing evidence of the toxicity associated with it.