What's new in the AFIP fascicle on salivary gland tumors: a few highlights from the 4th Series Atlas

Abstract

After a 12 year interval from the previous fascicle, a new fascicle on Tumors of the Salivary Glands in the new fourth series of the AFIP Atlas of Tumor Pathology was published in 2008. The data, presentation, illustrations, tables, and physical characteristics of the newest fascicle have been updated and improved. There have only been a few alterations and additions to the classification of tumors and tumor-like non-neoplastic conditions of salivary gland. Three of the most significant are discussed in this paper. Sialoblastoma has been reclassified as malignant; inflammatory pseudotumor has been reclassified as neoplastic and re-identified as inflammatory myofibroblastic tumor; and sclerosing polycystic adenosis is a new entity among tumor-like conditions.

Fig. 1

Sialoblastoma. Nests of basaloid cells have round, vesicular nuclei and poorly demarcated eosinophilic cytoplasm. Collagenous tissue of varying thickness separates tumor aggregates. There are foci of necrosis (top center) with dystrophic calcification

Fig. 2

Inflammatory myofibroblastic tumor. There are numerous inflammatory cells scattered among a nodular mass of spindled cells, which have a haphazard arrangement. Inset: The inflammatory cell infiltrate is composed of plasma cells, lymphocytes, histiocytes, and eosinophils

Fig. 3

Inflammatory myofibroblastic tumor. An immunostain for smooth muscle actin reacts with many of the spindled cells

Fig. 4

Sclerosing polycystic adenosis. There are many cystically dilated ducts as well as enlarged ducts with intraluminal epithelial hyperplasia (adenosis) within a sclerotic collagenous stroma. Note the area of nodular sclerosis on the right and the cystic duct with degenerating enlarged ductal cells with foamy cytoplasm on the left. Inset: acinar-like cells have enlarged eosinophilic cytoplasmic granules