Adult patients with supratentorial pilocytic astrocytoma: long-term follow-up of prospective multicenter clinical trial NCCTG-867251 (Alliance)

Abstract

Background Pilocytic astrocytoma is a rare tumor in adults. This report is of a prospective clinical trial with long-term follow-up. Methods Between 1986 and 1994, 20 eligible adults with supratentorial pilocytic astrocytomas were enrolled in a prospective intergroup trial of radiotherapy (RT) after biopsy (3 patients) or observation after gross (11 patients) or subtotal (6 patients) resection. Results At the time of analysis (median follow-up, 20.8 years), 2 patients (10%) have died and 18 patients (90%) are alive. Neurologic and cognitive function were stable or improved over time for the majority of patients. No toxic effects of treatment or malignant transformations have been recorded at last follow-up. For the entire cohort the 20-year time to progression and overall survival rates are 95% and 90% respectively. The cause of death (2.2 and 16.1 years after enrollment) in both patients was unrelated to tumor although both were biopsy-only patients. One subtotally resected tumor progressed 1 month after enrollment requiring P32 injection into an enlarging cyst. Because of further progression this patient required RT 18 months later. This patient is alive without evidence of progression 18 years after RT. Conclusion The long-term follow-up results of this prospective trial confirm that adults with pilocytic astrocytomas have a favorable prognosis with regard to survival and neurologic function. Close observation is recommended for adults with pilocytic astrocytomas, reserving RT for salvage, as the majority remain stable after gross or subtotal resection and no adjuvant therapy.

Short-term outcome following surgery for rare brain tumor entities in adults: a Swedish nation-wide registry-based study and comparison with SEER database

“…Of note, earlier series by Ye et al [15] reported up to 20% morbidity, 35% complication frequency and a 10% mortality, which are all higher than numbers reported in our cohort and a possible indication of improvement in surgical care over time. Finally, varying degree of adjuvant treatment has been reported, from 6-22% [14,15,17] with our frequency being 9.3%, which is more in line with overall recommendations from recent literature only to use radiotherapy as salvage [19], further substantiated by the demonstration of prolonged PFS but equal OS between adult patients with pilocytic astrocytoma that underwent GTR with-or without adjuvant radiotherapy [20].…”

Clinical characteristics and prognostic factors of adult patients with pilocytic astrocytoma

“…Adjuvant radiation after subtotal resection remains controversial, as the only so far conducted clinical trial did not include patients over 50 years and concentrated on patients with very favorable prognostic factors [25]. Other retrospective series indicate an added clinical benefit of radiation in case of unfavorable prognosis, however based on the limited available data, treatment decisions have to be made on an individual basis and should include tumor-and patient-specific parameters for prognostic assessment [17].…”

Heterogeneity of histopathological presentation of pilocytic astrocytoma – diagnostic pitfalls. A review

“…In adult patients, the majority of PAs are located supratentorially [14,18], less commonly in the cerebellum [96,100], cervicomedullary region [103] or other parts of the spinal cord [37,74,86]. Occasionally, PA in adult patients are associated with haemorrhages and manifest as spontaneous intracranial haemorrhage [57,59].…”