Case records of the Massachusetts General Hospital. Weekly clinicopathological exercises. Case 41-1980

Late BCNU lung: a light and ultrastructural study on the delayed effect of BCNU on the lung parenchyma

We describe eight patients who developed interstitial pulmonary fibrosis following BCNU (carmustine) therapy for cerebral tumours. The fibrosis presented 12-17 (mean 14) years after exposure to the drug. A distinctive pattern of pulmonary fibrosis with involvement of the apices and subpleural areas was seen in one patient dying of the disease. Light microscopy showed interstitial elastosis and intra-alveolar fibrosis which was often focal with an associated mild lymphoplasmacytic infiltrate, intra-alveolar oedema, macrophages, and some neutrophils. Ultrastructural studies showed electron lucency of type I pneumocytes, with breaks in the cytoplasmic membranes leaving a bare basement membrane. Degenerative change was also seen in endothelial cell cytoplasm along with lipofuscin deposition. While BCNU pulmonary fibrosis has been described up to 2 years after treatment, this complication so late after therapy, though rare, has important implications for the follow-up of patients receiving this drug.

BCNU (1,3-bis-(2-chloroethyl)-1-nitrosurea) lung. Drug-induced pulmonary changes

The occurrence of pulmonary disease associated with long-term BCNU therapy is reported in two patients treated for astrocytoma grade II whose clinical presentations of pulmonary complications and corresponding tissue alterations showed striking differences. One patient presented with a dramatic, fulminating, and rapidly fatal pulmonary disease. His lungs revealed atypical proliferation of pneumocytes, moderate interstitial inflammation, fibrosis and intra-alveolar hyalin membranes. The second patient presented with slowly progressive dyspnea, ultimately leading to death secondary to severe diffuse alveolar septal fibrosis. Individual differences in response to toxicity are suggested and discussed.

Fatal pulmonary toxic effects of lomustine

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D-Penicillamine-induced severe pneumonitis

We report the first histologically described case of severe D-penicillamine-induced pneumonitis. It occurred in a 73-year-old woman who suffered from rheumatoid arthritis and had previously demonstrated gold intolerance. Pathologic study disclosed marked interstitial and alveolar damage resembling that described with certain chemotherapeutic agents. We assess the drug's responsibility, discuss possible pathogenetic pathways, and provide suggestions regarding the patient on a D-penicillamine schedule.

Tumor cell anti-oxidant defenses. Inhibition of the glutathione redox cycle enhances macrophage-mediated cytolysis

The basis of resistance to oxidative injury was studied in six murine tumor cell lines that differed 54-fold in their resistance to enzymatically generated H(2)0(2). The tumors varied 56.7-fold in their specific activity of catalase, 5.3-fold in glutathione peroxidase (GPO), 3.3-fold in glutathione reductase (GR), and 2.7-fold in glutathione. There was no correlation among the levels of the three enzymes, and tumor cell resistance to lysis by H(2)0(2). However, the logarithm of the flux of H(2)0(2) necessary to cause 50 percent lysis of the tumor cells correlated with their content of glutathione (r = 0.91). The protective role of glutathione was analyzed by blocking GR and GPO, the catalysts of the glutathione redox cycle. This was facilitated by the demonstration that the anti-neoplastic agent 1,3-bis-(2- chloroethyl)-l-nitrosourea (BCNU) was a potent inhibitor of GR in intact tumor cells. BCNU inactivated tumor cell GR with a 50 percent inhibitory dose of 11 muM and a t(l/2) of inhibition of 30 s. Complete inhibition of GR was attained with no effect on GPO or catalase. Tumor cells whose GR was inactivated by BCNU could be lysed by fluxes of H(2)0(2) to which they were otherwise completely resistant. They could be killed by phorbol myristate acetate (PMA)-stimulated, bacilli Calmette-Guerin-activated macrophages in numbers which were otherwise insufficient, and by nonactivated macrophages, which otherwise were ineffective. BCNU-treated target cells were also much more sensitive to antibody-dependent, macrophage-mediated cytolysis. However, such tumor cells were no more sensitive than controls to lysis by alloreactive T cells or by antibody plus complement. Next, we deprived tumor cells of selenium by passage in selenium-deficient mice. GPO was inhibited 85 percent in such cells, with no effect on GR or catalase. Tumor cells with reduced GPO activity were markedly sensitized to lysis by small fluxes of H(2)0(2) or by PMA-stimulated macrophages or granulocytes. In contrast, inhibition of catalase with aminotriazole had no effect on the sensitivity of three tumors to peroxide-mediated lysis, and had modest effects with two others. Thus, the oxidation-reduction cycle of glutathione serves as one of the major defense mechanisms of tumor cells against three related forms of oxidant injury: lysis by fluxes of H(2)0(2), by PMA-triggered macrophages, and by macrophages in the presence of anti-tumor antibody.