Hemangioblastoma histopathology

(A1 and A2) Hemangioblastomas have abundant reticulin and often smear poorly. However, some intraoperative smears show cells with significant cytoplasm and pleomorphic, hyperchromatic nuclei (A1). If not destroyed in the smear preparation, an occasional classic stroma cell with its many vacuoles may survive (A2).

(B) The tumor has two main components: a fine vascular network and intermixed stromal cells (thick arrows).

(C) Tumor cells sometimes have a clear cell morphology or can have more pink cytoplasm (thick arrows). These cells are embedded among numerous vessels.

(D) The stromal cells range from moderate-sized cells with eosinophilic cytoplasm to large cells having abundant vacuoles that impinge on the nucleus, forming scalloped nuclear borders (thin arrows). The anaplastic nuclei are histologically worrisome but portend no aggressive behavior.