[Multiple primary neoplasm--glioblastoma combined with cancer of other organs]

A combination of multiple primary neoplasm (MPN) with glioblastoma and cancer of other organs is extremely rare but might be spurred up in the field of neurosurgery because of increasing number of cured patients from cancer or malignant brain tumor. Four such cases are presented. Two of them are of heterochronous occurrence of tumors. One has survived for 17 years after treating four malignancies: uterus, stomach, breast cancer and glioblastoma multiforme in this order and free of brain tumor for 4 years. The other has survived 18 years after three malignancies: uterus, stomach cancer and glioblastoma but is in morbid neurological state for a year. A case of synchronous primary tumors is a combination with glioblastoma and maxillary cancer and the patient died of brain tumor after 4 years and two months. The other case is an old man with glioblastoma and stomach cancer but died of severe general and neurological condition for three months before treatment was started. The pathogenesis of MPN is unknown. Regarding intrinsic factors, heredity, age, genetic or immunological state have been proposed for possible mechanism of the synchronous occurrence of MPN. While extrinsic factors such as environmental changes due to irradiation or chemical exposure to host might also be important for heterochronous MPN. Discussions based on these cases and literature were also made on the biological nature and clinical characteristics of MPN malignant brain tumor combined with cancer of other organs.