The significance of morphologically viable glioma cells found at the time of operation after interstitial brachytherapy.
The significance of finding morphologically intact viable glioma cells in tumors treated with high-dose irradiation delivered by interstitial brachytherapy was examined. Freshly resected tissue was taken from 12 patients after (n = 8) or both before and after (n = 4) interstitial brachytherapy. All posttreatment tissue was taken from regions within a radius of 2.0 to 4.0 cm of the radioactive source. From each sample, monolayer cell culture was established. All untreated samples from primary tumors grew well and became established as cell lines within 1 to 3 weeks. In contrast, cells from treated tumors only formed small colonies of 50 to 100 cells each. These cells grew slowly and, within 14 to 21 days, degenerated. Neither the use of conditioned medium or cell extract from established glioma cell lines nor the application of growth factors (platelet-derived growth factor and/or epidermal growth factor) stimulated growth or lengthened survival. The only exception was tumor resected from approximately 4 cm from the nearest radioactive source and from which a viable cell line could be established (IRR). Cytogenetic analysis of tissue from one sample (IR) before source implantation and from another (IRR) after source implantation, both from the same patient, showed that cells IR and IRR were derived from the same stem cell. To establish the reason why cell IRR remained clonogenic despite high-dose irradiation, IRR cells were irradiated with gamma irradiation with a dose rate of approximately 1 Gy/min for 24 hours. This colony-forming assay showed that IRR cells were radiosensitive.(ABSTRACT TRUNCATED AT 250 WORDS)
Arbit
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Neurosurgery Service, Memorial Sloan-Kettering Cancer Center, New York, New York.
Shapiro
J R
JR
Fiola
M
M
Malkin
M G
MG
Galicich
J H
JH
D001254:Astrocytoma / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D001918:Brachytherapy; D001932:Brain Neoplasms / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D002455:Cell Division / Q000528:radiation effects; D002470:Cell Survival / Q000528:radiation effects*; D003131:Combined Modality Therapy; D016371:Cranial Irradiation; D005500:Follow-Up Studies; D005909:Glioblastoma / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D006801:Humans; D015996:Survival Rate; D014407:Tumor Cells, Cultured / Q000528:radiation effects*; D014410:Tumor Stem Cell Assay