What progress has been made in surgical management of patients with astrocytoma and oligodendroglioma in Australia over the last two decades?

BACKGROUND: Most primary brain cancers are associated with a dismal prognosis because of their aggressive behaviour and high mortality. Surgical resection with adjuvant radiotherapy is a major treatment for these cancers but little has been published about their surgical management in Australia. OBJECTIVE: To determine changes since 1977 in demographic characteristics, tumour frequencies, surgical management, morbidity and survival for 1,339 patients discharged with astrocytoma (A) and oligodendroglioma (O), which comprise the majority of primary brain cancers, recorded prospectively in northern Sydney neurosurgery databases. Discharges were grouped into eras reflecting changes in diagnostic and surgical technology. RESULTS: Between eras 1977-79 and 1999-2002, mean age increased by 9.5 years, and inpatient stay fell from 21 to 9 days. The proportion of O rose as A fell. Of 144 re-biopsies, 16% had less anaplastic pathology, 54% the same and 30% more anaplastic pathology than the first biopsy. Stereotactically assisted surgery increased, with overall rates of burr hole for biopsy decreasing and of craniotomy rising. Between 1980-86 and 1999-2002, inpatient mortality declined from 7.3 to 2.3% of discharges, reopening of craniotomy and wound complication rates fell, while postoperative neurological deficit rose. Deep vein thrombosis and pulmonary embolism rates for discharges increased significantly. Age and histopathologic grade were predictors of survival from 1980. Sex and era of diagnosis did not influence survival. After adjustment for age using proportional hazards regression, survival improved only for anaplastic A, with a 60% improvement for patients diagnosed in era 3, and a 50% improvement for patients diagnosed in era 4 relative to those in era 1. CONCLUSIONS: Although markers of inpatient care have improved since the 1980s, age-adjusted survival has not increased except for patients with anaplastic A.