Image 31 of 95



Image Description

Gross Pathology: Botryoid rhabdomyosarcoma (RMS) has a characteristic polypoid, grape-like gross appearance (botryoid = Greek for bunch of grapes). It is usually found in mucosa-lined hollow viscera such as urinary bladder, vagina, nasal cavity, nasopharynx, and the common bile duct. The specimen shown here involved the nasopharynx.

In these locations, the tumor encounters little or no resistance in its outward growth and projects into the lumen as a polypoid, multinodular, edematous mass resembling a bunch of grapes. In rare instances, RMS arising in locations such as eyelid or the anal region reaches the body surface and can acquire polypoid/grape-like appearance.

Note: Despite earlier definitions, the International Classification of Rhabdomyosarcoma does not required grape-like gross appearance for the diagnosis of botryoid RMS. However, a cambium layer must be present. It is a subepithelial condensed layer of tumor cells that is separated from the overlying epithelium by loose myxoid stroma.

Image courtesy of Dr. Jean-Christophe Fournet, Paris, France; humpath.com; Used with permission

Image 31 of 95