2020-39 / September 28
Contributors: Kelly Guggisberg, Connie Liao, Asli Yilmaz

A man in his late 30s presented with a 1.5 cm solid nodule at the head of the left epididymis.


1. What is the diagnosis?

a) Papillary cystadenoma

b) Adenomatoid tumor

c) Metastatic clear cell renal cell carcinoma

d) Well-differentiated papillary mesothelioma

e) Serous borderline tumor


2. What is the syndrome associated with this lesion?

a) MEN1

b) von Hippel Lindau

c) Birt-Hogg Dube

d) Neurofibromatosis I

e) Lynch Syndrome

1. a
2. b

1. Papillary cystadenoma
2. von Hippel Lindau

Papillary cystadenoma is a rare benign epithelial tumor of the epididymis. It usually occurs in young adults. There is a strong association with von Hippel Lindau syndrome, especially in patients presenting with bilateral papillary cystadenoma. The immunohistochemical staining pattern and morphology of papillary cystadenoma is similar to that of clear cell (tubulo)papillary renal cell carcinoma (CK7, CAIX, PAX8 positive, AMACR negative). The absence of a renal mass and non-metastatic clinical behavior of clear cell (tubulo)papillary RCC is helpful to establish the correct diagnosis.

Toutziaris C, Kampantais S, Perdikis I, Gourvas V, Laskaridis L, Gkagkalidis K, Lakis S and Ioannidis S. Papillary cystadenoma of epididymis: Is there a need for further investigation in unilateral cases. Int J. Surg Case Rep. 2013; 4(7): 616-618.

Cox, R, Vang R, Epstein J. Papillary cystadenoma of the epididymis and broad ligament: morphologic and immunohistochemiccal overlap with clear cell papillary renal cell carcinoma. Am. J. Surg Pathology. 2014; 38(5): 713-8.

Kelly Guggisberg
Connie Liao
Asli Yilmaz

University of Calgary
Calgary, Alberta, Canada


epididymis, paratesticular, papillary cystadenoma