Objective: It was the aim of this study to determine the utility of PAX2 and PAX8 in cytology effusions with metastatic tumor. Study Design: PAX2 and PAX8 immunohistochemical staining was performed on cell blocks of 89 pleural, pericardial and peritoneal effusions with benign diagnoses (18 cases), or secondary to renal cell carcinoma (RCC; 9 cases), müllerian carcinoma (21 cases) or non-müllerian carcinoma (41 cases). Results: PAX2 stained 0% (0/18) of controls, 100% (8/8) of RCCs, 35% (7/20) of müllerian carcinomas, and 2% (1/41) of non-müllerian carcinomas. PAX8 stained 6% (1/18) of control cases, 100% (9/9) of RCC cases, 100% (20/20) of müllerian carcinomas, and 5% (2/41) of non-müllerian carcinomas. PAX2 was 35% sensitive and 95% specific for müllerian carcinoma and 100% sensitive and 95% specific for RCC. PAX8 was 100% sensitive and 95% specific for müllerian carcinoma and 100% sensitive and 95% specific for RCC. Conclusions: PAX8 is more sensitive than PAX2 for metastatic effusions from müllerian carcinomas (100 vs. 35%), while also having a higher intensity of staining than PAX2. However, PAX2 and PAX8 are both highly sensitive and specific for RCCs. PAX2 and PAX8 are valuable diagnostic markers for metastatic müllerian carcinomas and RCCs in effusion cytology. PAX8 is superior for carcinomas of müllerian origin.

1.
Wiseman W, Michael CW, Roh MH: Diagnostic utility of PAX8 and PAX2 immunohistochemistry in the identification of metastatic Müllerian carcinoma in effusions. Diagn Cytopathol 2011;39:651-656.
2.
Gokden N, Kemp SA, Gokden M: The utility of PAX-2 as an immunohistochemical marker for renal cell carcinoma in cytopathology. Diagn Cytopathol 2008;36:473-477.
3.
Skoog L, Tani E: Immunocytochemistry: an indispensable technique in routine cytology. Cytopathology 2011;22:215-229.
4.
Zhu W, Michael CW: WT1, monoclonal CEA, TTF1, and CA125 antibodies in the differential diagnosis of lung, breast, and ovarian adenocarcinomas in serous effusions. Diagn Cytopathol 2007;35:370-375.
5.
Lee BH, Hecht JL, Pinkus JL, Pinkus GS: WT1, estrogen receptor, and progesterone receptor as markers for breast or ovarian primary sites in metastatic adenocarcinoma to body fluids. Am J Clin Pathol 2002;117:745-750.
6.
Sangoi AR, Karamchandani J, Kim J, Pai RK, McKenney JK: The use of immunohistochemistry in the diagnosis of metastatic clear cell renal cell carcinoma: a review of PAX-8, PAX-2, HKIM-1, RCCma, and CD10. Adv Anat Pathol 2010;17:377.
7.
Ozcan A, de la Roza G, Ro JY, Shen SS, Truong LD: PAX2 and PAX8 expression in primary and metastatic renal tumors: a comprehensive comparison. Arch Pathol Lab Med 2012;136:1541-1551.
8.
Pan CC, Chen PCH, Ho DMT: The diagnostic utility of MOC31, BEREP4, RCC marker and CD10 in the classification of renal cell carcinoma and renal oncocytoma: an immunohistochemical analysis of 328 cases. Histopathology 2004;45:452-459.
9.
Bowen NJ, Logani S, Dickerson EB, Kapa LB, Akhtar M, Benigno BB, McDonald JF: Emerging roles for PAX8 in ovarian cancer and endosalpingeal development. Gynecol Oncol 2007;104:331-337.
10.
Rabban JT, McAlhany S, Lerwill MF, Grenert JP, Zaloudek CJ: PAX2 distinguishes benign mesonephric and mullerian glandular lesions of the cervix from endocervical adenocarcinoma, including minimal deviation adenocarcinoma. Am J Surg Pathol 2010;34:137.
11.
Tong GX, Chiriboga L, Hamele-Bena D, Borczuk AC: Expression of PAX2 in papillary serous carcinoma of the ovary: immunohistochemical evidence of fallopian tube or secondary Müllerian system origin? Mod Pathol 2007;20:856-863.
12.
Tong GX, Woojin MY, Beaubier NT, Weeden EM, Hamele-Bena D, Mansukhani MM, O'Toole KM: Expression of PAX8 in normal and neoplastic renal tissues: an immunohistochemical study. Mod Pathol 2009;22:1218-1227.
13.
Truong LD, Shen SS: Immunohistochemical diagnosis of renal neoplasms. Arch Pathol Lab Med 2011;135:92-109.
14.
Daniel L, Lechevallier E, Giorgi R, Sichez H, Zattara-Cannoni H, Figarella-Branger D, Coulange C: Pax-2 expression in adult renal tumors. Hum Pathol 2001;32:282-287.
15.
Ozcan A, Shen SS, Hamilton C, Anjana K, Coffey D, Krishnan B, Truong LD: PAX8 expression in non-neoplastic tissues, primary tumors, and metastatic tumors: a comprehensive immunohistochemical study. Mod Pathol 2010;24:751-764.
16.
Ozcan A, Liles N, Coffey D, Shen SS, Truong LD: PAX2 and PAX8 expression in primary and metastatic müllerian epithelial tumors: a comprehensive comparison. Am J Surg Pathol 2011;35:1837.
17.
Mazal PR, Stichenwirth M, Koller A, Blach S, Haitel A, Susani M: Expression of aquaporins and PAX-2 compared to CD10 and cytokeratin 7 in renal neoplasms: a tissue microarray study. Mod Pathol 2004;18:535-540.
18.
Wasco MJ, Pu RT: Comparison of PAX-2, RCC antigen, and antiphosphorylated H2AX antibody (gamma-H2AX) in diagnosing metastatic renal cell carcinoma by fine-needle aspiration. Diagn Cytopathol 2008;36:568-573.
19.
Knoepp SM, Kunju LP, Roh MH: Utility of PAX8 and PAX2 immunohistochemistry in the identification of renal cell carcinoma in diagnostic cytology. Diagn Cytopathol 2012;40:667-672.
20.
Roh MH, Kindelberger D, Crum CP: Serous tubal intraepithelial carcinoma and the dominant ovarian mass: clues to serous tumor origin? Am J Surg Pathol 2009;33:376-383.
21.
Chivukula M, Dabbs DJ, O'Connor S, Bhargava R: PAX2: a novel Müllerian marker for serous papillary carcinomas to differentiate from micropapillary breast carcinoma. Am J Gynecol Pathol 2009;28:570.
22.
Nonaka D, Chiriboga L, Soslow RA: Expression of PAX8 as a useful marker in distinguishing ovarian carcinomas from mammary carcinomas. Am J Surg Pathol 2008;32:1566.
23.
Tung CS, Mok SC, Tsang YTM, Zu Z, Song H, Liu J, Deavers MT, Malpica A, Wolf JK, Lu KH: PAX2 expression in low malignant potential ovarian tumors and low-grade ovarian serous carcinomas. Mod Pathol 2009;22:1243-1250.
24.
Gokden N, Gokden M, Phan DC, McKenney JK: The utility of PAX-2 in distinguishing metastatic clear cell renal cell carcinoma from its morphologic mimics: an immunohistochemical study with comparison to renal cell carcinoma marker. Am J Surg Pathol 2008;32:1462-1467.
25.
Laury AR, Hornick JL, Perets R, Krane JF, Corson J, Drapkin R, Hirsch MS: PAX8 reliably distinguishes ovarian serous tumors from malignant mesothelioma. Am J Surg Pathol 2010;34:627.
26.
McKnight R, Cohen C, Siddiqui MT: Utility of paired box gene 8 (PAX8) expression in fluid and fine-needle aspiration cytology. Cancer Cytopathol 2010;118:298-302.
27.
Tong GX, Devaraj K, Hamele-Bena D, Yu WM, Turk A, Chen X, Wright JD, Greenebaum E: PAX8: a marker for carcinoma of Müllerian origin in serous effusions. Diagn Cytopathol 2010;39:562-566.
28.
Schmitt AC, Cohen C, Siddiqui MT: Paired box gene 8, HBME-1, and cytokeratin 19 expression in preoperative fine-needle aspiration of papillary thyroid carcinoma: diagnostic utility. Cancer Cytopathol 2010;118:196-202.
29.
Olson MT, Nuransoy A, Ali SZ: Malignant pleural effusion resulting from metastasis of thyroid primaries: a cytomorphological analysis. Acta Cytol 2013;57:177-183.
30.
Ko EC, Jhala NC, Shultz JJ, Chhieng DC: Use of a panel of markers in the differential diagnosis of adenocarcinoma and reactive mesothelial cells in fluid cytology. Am J Clin Pathol 2001;116:709-715.
31.
Zhao L, Guo M, Sneige N, Gong Y: Value of PAX8 and WT1 immunostaining in confirming the ovarian origin of metastatic carcinoma in serous effusion specimens. Am J Clin Pathol 2012;137:304-309.
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