Purpose: To examine the effects of lomustine (CCNU), a commonly used nitrosourea, and craniospinal radiation therapy on the subsequent development of restrictive lung disease (RLD) following treatment for malignant brain tumors.
Patients and methods: Pulmonary function testing with measurement of lung volume, spirometry, and diffusion capacity was performed in 28 patients who had received CCNU and/or radiation therapy as treatment for a malignant brain tumor. The median age at the time of treatment was 11.4 years (range, 3.9 to 36.7) and radiation therapy was completed 6 months to 11.6 years (median, 2.6 years) before testing. Patients were divided into four groups based on prior therapy. Group 1 received involved-field irradiation and a CCNU-containing chemotherapy regimen (n = 7); group 2, craniospinal irradiation with a boost to the primary tumor site and a CCNU-containing chemotherapy regimen (n = 6); group 3, craniospinal irradiation with a boost to the primary tumor site and a non-CCNU-containing chemotherapy regimen (n = 7); and group 4, craniospinal irradiation with a boost to the primary tumor site without chemotherapy (n = 8).
Results: Fourteen patients (50%) had findings consistent with RLD. One of seven patients (14.3%) who received CCNU without spinal irradiation had RLD, whereas 13 of 21 (61.9%) who received spinal irradiation with or without CCNU had RLD (P = .038), including four of eight patients treated with craniospinal irradiation alone. Logistic regression analysis showed that only spinal irradiation was a significant predictor for RLD. Patients who received spinal irradiation were 4.3 times more likely to have RLD than those who did not receive spinal irradiation.
Conclusion: Spinal irradiation may be a risk factor for the development of RLD.