[1242] Transitional Cell Tumors of Ovary: Immunohistochemical Profile with Reference to Markers for Transitional Cell Carcinoma

John Schwartz, Mitual Amin. William Beaumont Hospital, Royal Oak, MI

Background: Transitional cell tumors of ovary are a set of tumors that resemble tumors of the urothelium. They are relatively uncommon and comprise approx. 1-2% of all ovarian tumors. In rare instances one may have to differentiate these tumors from metastatic transitional cell carcinomas (TCC) to ovary. There has been recent interest in numerous markers, especially PAX8 and PAX2. The immunohistochemical profile of these tumors is not well studied.
Design: Paraffin blocks from 15 cases of benign Brenner tumor were selected for staining. In addition, we studied 4 cases that were diagnosed in our institution as being transitional cell carcinomas (TCC) of ovary and one case that was a metastatic TCC from the bladder. Six immunostains were performed on these cases - PAX2, PAX8, CK7, CK20, p-63 and uroplakin. Immunostains were graded visually for extent of staining 0 (0%), 1+ (1-33%), 2+ (34-66%) and 3+ (>67%); and for intensity of staining as 1+ (weak), 2+ (moderate) and 3+ (strong).
Results: Benign Brenner tumors showed positive staining with CK7 in 92% (12/13), p63 in 92% (11/12) and PAX8 in 7% (1/14). These tumors showed no staining with CK20 (0/12), uroplakin (0/8) and PAX2 (0/12). Cases of ovarian TCC showed positivity for CK7 and PAX8 in 4/4 cases; and p-63 in 1/4 cases. None of these cases stained with CK20, uroplakin and PAX2. One case of metastatic TCC from bladder showed positivity for CK7, PAX2, PAX8 and p63, with negative staining for uroplakin and CK20.
Conclusions: Transitional cell tumors of ovary appear immunophenotypically different from transitional cell tumors of the urinary tract. Brenner tumors are CK7+/CK20-/p63-/uroplakin-/PAX2-/PAX8- and do not share immunophenotype of urinary tract TCCs. PAX8 is known to be strongly positive in thyroid tissues and our one case of Brenner tumor that showed PAX8 positivity had concomitant struma ovarii. TCCs of ovary similarly are CK7+/PAX8+/CK20-/p63-/uroplakin-/PAX2-. The positivity noted with PAX8 stain likely reflects the mullerian origin of tumor. These tumors were high grade and the possibility of admixed serous carcinoma is not excluded. The metastatic TCC showed an immunophenotype of its parent tumor and this is distinct from the staining pattern of all the other tumors. We did not have any cases of borderline and malignant Brenner tumors. Additional immunostains (ER and WT-1) are in process for further immunophenotypic characterization of these tumors.
Category: Gynecologic & Obstetrics

Wednesday, March 21, 2012 9:30 AM

Poster Session V # 155, Wednesday Morning

 

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