Sex-dependent expression of prostatic markers and hormone receptors in cystic tumor of the atrioventricular node: A histopathological study of three cases

We pathologically investigated three autopsy cases of cystic tumor of the atrioventricular node (CTAVN) with sudden death. Case 1 was a 36-year-old woman without any clinical history. Case 2 was a 76-year-old man with an implanted pacemaker for complete atrioventricular block. Case 3 was a 45-year-old man with a history of first-degree AV block and sinus bradycardia. Microscopically, all three cases showed the bilayered structure of tumor glands and corpora amylacea in the glandular lumens. Immunohistochemically, the inner cells of the tumor glands were positive for cytokeratin CAM5.2, CEA, EMA, olfactomedin-4 and alpha-methylacyl-coenzyme A racemase; the outer cells were positive for p63 and cytokeratin high molecular weight. In Case 1, androgen receptor and estrogen receptor were negative; progesterone receptor was focally positive in both the inner and outer cells. In Case 2, androgen receptor showed intermediate positivity in the inner cells; estrogen receptor and progesterone receptor were positive in the outer cells. Positive expression of both prostate-specific antigen and prostate-specific acid phosphate were found in the inner cells of both male cases. Because CTAVN cells exhibit different degrees of the prostatic phenotype depending on the patient's sex, we believe that CTAVN may originate from urogenital sinus tissue in some cases.

Cystic tumor of the atrioventricular node: a review of the literature

Primary cardiac tumors are uncommon clinical entities with an incidence of 0.0017% to 0.03% of all autopsies. Cystic tumor of the atrioventricular (AV) node, also known as mesothelioma of the AV node, is a benign congenital tumor that is located in the triangle of Koch in the AV nodal region of the atrial septum of the heart. It comprises of 2.7% of cardiac tumors and is the most common primary cardiac tumor causing sudden death. We herein review the etiology, presentation, differential diagnosis, diagnosis, management, surgical approaches and outcomes of this rare tumor.

Cardiac Tumors

Cardiac neoplasms and other mass-forming lesions are not commonly encountered in surgical pathology practice. Fortunately, for the most part, these fall into a small group of well characterized and readily-recognized entities, although they are not without diagnostic dilemmas. A brief and practical synopsis of cardiac tumors is presented in this section with attention to more frequently encountered and clinically significant diagnostic challenges as well as pertinent clinical associations and prognostic information.