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Methods and Materials: Inclusion criteria included the following: biopsy-proven supratentorial malignant astrocytoma of brain ≤6 cm in size, not crossing midline or involving corpus callosum, age 18–70, Karnofsky Performance Status (KPS) ≥70. Patients were randomized to external radiation therapy only delivering 50 Gray (Gy) in 25 fractions over 5 weeks or external radiation therapy plus a temporary stereotactic iodine-125 implants delivering a minimum peripheral tumor dose of 60 Gy. Patients were stratified to age ≤50 or >50, and KPS ≥90 or ≤80.
Results: There were 140 patients randomized between 1986 and 1996, 71 to the implant arm and 69 to external irradiation only. Pathologically 125 patients had necrosis noted in their tumor specimen. Factors associated with improved survival in univariate analysis were age ≤50, KPS ≥90, chemotherapy at recurrence, and reoperation at the original tumor site. The Cox proportional hazards model revealed the following significant factors: treatment at recurrence (chemotherapy or reoperation) with a relative risk (RR) of 0.6 (p = 0.004) and KPS ≥90 with a RR 0.6 (p = 0.007). Randomization to the implant arm was associated with a RR of 0.7 (p = 0.07). Median survival for patients randomized to brachytherapy or not were 13.8 vs. 13.2 months, respectively, p = 0.49.
Conclusions: We conclude that stereotactic radiation implants have not demonstrated a statistically significant improvement in survival in the initial management of patients with malignant astrocytoma. 相似文献
Methods: A prospective cohort study was conducted with 500 pregnant women with severe preeclampsia. The mode of delivery, vaginal or caesarean section, was considered the exposure, while the postpartum maternal complications and severe maternal morbidity were the outcomes. Logistic regression analysis was performed to determine the adjusted risk and 95% confidence intervals (95% CI) of maternal morbidity.
Results: Labour was spontaneous in 22.0% and induced in 28.2%, while 49.8% had an elective caesarean section. Ninety-five (67.4%) of the patients in whom labour was induced delivered vaginally. Total Caesarean rate was 68.2%. The risk of severe maternal morbidity was significantly greater in patients submitted to Caesarean section (54.0% versus 32.7%) irrespective of the presence of labour. Factors that remained associated with severe maternal morbidity following multivariate analysis were a diagnosis of HELLP syndrome after delivery (OR?=?3.73; 95% CI: 1.55–9.88) and having a caesarean (OR?=?1.91; 95% CI: 1.52–4.57).
Conclusions: Caesareans are often performed in patients with severe preeclampsia and are associated with significant postpartum maternal morbidity. Induction of labour should be considered a feasible option in these patients. 相似文献