Cytological features in pilomyxoid astrocytoma: A case report with summary of prior published cases

Abstract

Pilomyxoid astrocytoma is a subtype of pilocytic astrocytoma that is described as a grade 1 tumour in the 2022 WHO classification of central nervous system tumours. It occurs predominantly in the hypothalamic region in infants. Although the histological features of pilomyxoid astrocytomas are well documented, few reports are available in the literature regarding cytological findings. Here we describe the squash cytological features of a case of pilomyxoid astrocytoma along with a summary of prior published cases. Smears for this type of tumour tend to be more cellular, with piloid cells arranged in an angiocentric pattern without Rosenthal fibres or eosinophilic granular bodies. A blue myxoid substance may be present in the background.

Cytological features of chordoid glioma: A case report with summary of prior published cases

“…The pilomyxoid astrocytoma, though has a myxoid background is seen mainly in very young children and occurs near the optic chiasma. Cytologically long elongated piloid processes are there along with perivascular distribution and there is no lymhocytic infiltration 7 …”

“…Cytologically long elongated piloid processes are there along with perivascular distribution and there is no lymhocytic infiltration. 7 Chordoma can be seen in children and young adults and involve the third ventricle. It is composed of physaliferous cells which are vacuolated cells arranged in chords in a myxoid background, Lymphocytes are lacking in this tumour.…”

Cytological features of diffuse and circumscribed gliomas

“…It is composed of piloid cells in a myxoid background and exhibits an angiocentric arrangement of tumoral cells. 21,22 PA with histological features of anaplasia occurs predominantly in adults. Despite showing necrosis and having a high mitotic index it is a WHO grade 1 tumour.…”

“…Despite showing necrosis and having a high mitotic index it is a WHO grade 1 tumour. [4][5][6][7][8]16,17,[20][21][22] • Moderately cellular smears with a fibrillar and myxoid background • Loosely arranged aggregates and single cells with an evident fibrillary aspect (Figure 6A,B) • Pilocytic cells: bipolar elongated cell with an oval nucleus and two slender, hair-like cytoplasmic processes (Figure 6A,B) • Rosenthal fibres and eosinophilic granular bodies (Figure 6C,D) • Uniform round to oval nuclei with no atypia. Degenerative hyperchromatic nuclei and giant cells are occasionally present (Figure 6F)…”

Optic nerve pilomyxoid astrocytoma: Intraoperative squash smear cytology of a rare entity

“…Although histopathological features of PMA are well described, but the cytomorphological features are rarely described. [6][7][8] Here, we describe the cytological features of PMA and discuss its differential diagnosis.…”