Recurrence and progression of elderly-onset pilocytic astrocytoma spontaneously regressed at first presentation

Abstract

Pilocytic astrocytoma is a benign World Health Organization grade 1 tumor and usually occurs in young patients. This tumor can occur in adults, yet relatively few arise in those who are older than 50 years. The tumor histology is characterized by a biphasic pattern with compacted bipolar cells associated with Rosenthal fibers and loose-textured multipolar cells associated with microcysts and eosinophilic granular bodies/hyaline droplets. Tumor-growth is always slow, and occasionally regressive changes are observed mainly for tumors in children and associated with neurofibromatosis type 1.

We previously reported a unique case of pilocytic astrocytoma diagnosed for 64-year-old woman. This case was noteworthy in two points: the patient was an elderly adult without clear comorbidity; the patient’s tumor spontaneously regressed in short term before surgery. Here we report the follow-up clinical course.

She was uneventfully followed up without additional therapy after complete lesionectomy, but the tumor recurred at the 45-month after surgery. While the histological pattern of recurred tumor imitated that of diffuse astrocytoma, the immunohistochemical profiles did not changed from the first presentation.

Several reports provided the information about non-indolent clinical courses of adult-onset pilocytic astrocytoma. We should be cautious about this entity and the subtyping of IDH wild type tumor group to which pilocytic astrocytoma belongs.