Palma L, Vagnozzi R, Annino L, Ciapetta P, Maleci A, Cantore G
Cattedra di Neurochirurgia, Istituto di Scienze Neurologiche, Policlinico Le Scotte, Siena, Italy.
Childs Nerv Syst. 1988 Oct;4(5):296-301.
A case of primary brain neoplasm is reported that developed 11 years after prophylactic brain irradiation and intrathecal methotrexate (MTX) given for acute lymphocytic leukemia (ALL) at the age of 3 years. Cases of supposed postirradiation gliomas in children seem to have increased in recent years, particularly following apparently successful treatment for ALL or medulloblastoma. This increase might reflect the increased number of long-surviving cancer children and thus suggest that brain irradiation may be a potential risk factor in this population. After reviewing some general data on neurooncogenesis, two points are stressed: (1) the child's brain is particularly susceptible to the mutagenic effects of ionizing radiation owing to physiologically active postnatal glial cell proliferation, which takes place in the cerebral hemispheres, especially during myelinogenesis; (2) MTX could promote glial neoplasm by enhancing reparative glial cell proliferation. Prospective studies seem necessary to show whether or not prophylactic brain radiation in ALL plays an oncogenetic role. Nevertheless, besides recurrent leukemia, leukoencephalopathy, and radionecrosis, the remote possibility of radiation-induced glial neoplasms should always be considered in cases of children treated for leukemia who present with neurological complications.
报告了一例原发性脑肿瘤病例，该病例发生在3岁时因急性淋巴细胞白血病（ALL）接受预防性脑部放疗和鞘内注射甲氨蝶呤（MTX）11年后。近年来，儿童中疑似放疗后胶质瘤的病例似乎有所增加，尤其是在ALL或髓母细胞瘤的治疗明显成功之后。这种增加可能反映了长期存活的癌症儿童数量的增加，因此表明脑部放疗可能是这一人群的潜在危险因素。在回顾了一些关于神经肿瘤发生的一般数据后，强调了两点：（1）由于出生后神经胶质细胞的生理性活跃增殖，儿童大脑对电离辐射的诱变作用特别敏感，这种增殖发生在大脑半球，尤其是在髓鞘形成期间；（2）MTX可通过增强修复性神经胶质细胞增殖来促进神经胶质瘤的发生。前瞻性研究似乎有必要表明ALL中的预防性脑部放疗是否起致癌作用。然而，除了复发性白血病、白质脑病和放射性坏死外，对于出现神经并发症的白血病患儿，应始终考虑放疗诱发神经胶质瘤的可能性。
