[1082] Pap Cytology and Hybrid Capture 2 HPV DNA Testing in 234 Patients with Cervical Squamous Cell Carcinoma.

Zaibo Li, Marshall R Austin, Ming Guo, Chengquan Zhao. Magee Women's Hospital of UPMC, Pittsburgh, PA; The University of Texas MD Anderson Cancer Center, Houston

Background: Cervical cancer screening with Pap cytology and HPV DNA testing is highly sensitive in predicting cervical precancerous lesions (CIN2/3). However, patients with CIN2/3 or even carcinoma can be missed during the screening. To evaluate the factors that resulted in the screening failure, we compared history of Pap cytology and HPV DNA testing results in patients with cervical squamous cell carcinoma (SQC).
Design: We conducted a computer-based search for a 5-year period and collected the results of surgical pathology, ThinPrep Pap, and Hybrid Capture 2 (HC2) HPV DNA testing from patients with cervical SQC. HPV DNA testing using PCR was performed on the surgical specimens from the cases with negative HC2 test.
Results: 234 patients with SQC were identified, including 35 cases of microinvasive SQC. The average age was 48 years (22 to 84 years). The clinical or Pap findings leading to the diagnostic biopsies are detailed in table 1.

Findings Leading to Histopathologic Diagnoses of SQC

		No. of Patients (% of subcategory)	%
Unknown		50	21.4%
Clinical Findings		57	24.4%
	Bleeding	13 (22.8%)
	cervical lesions	44 (77.2%)
Pap Findings		127	54.3%
	ASCUS	8 (6.3%)
	ASC-H	6 (4.7%)
	LSIL	3 (2.4%)
	HSIL	80 (63.0%)
	SCC/suspicious	27 (21.3%)
	AGC	3 (2.4%)
Total		234	100%

34 patients had prior Pap and the results were listed in table 2.

Pap Histories Over 3 Years Preceding Histopathologic Diagnoses of SQC

Pap Test	Case No.	%
At least one prior abnormal Pap	22	64.7%
At least one prior normal Pap	15	44.1%
Both prior normal and abnormal Pap	3	8.8%

Abnormal Pap tests triggering the biopsy for diagnosis of SQCs were not included.

28 patients had HC2 HPV DNA tests within 5 months before the histologic diagnosis. HC2 HPV DNA was tested positive in 24 patients (86%), while negative in 4 patients (14%). However, HPV DNA was detected by PCR in the surgical specimens from the 4 patients with a negative HC2 test.
Conclusions: HSIL was the most frequent abnormal cytology to trigger the histologic diagnosis of SQCs. 44% of cases had at least one negative Pap test within 3 years prior to the histologic diagnosis. We found a fractional (14%) false negative HC2 HPV rate in patients with cervical SQC, which is similar to the false negative HC2 HPV rate (11%) recently reported in the Kaiser Permanente system after cytology and HPV co-testing. False negative HC2 HPV results argue against the proposed cervical cancer screening with primary HPV screening and secondary Pap cytology.
Category: Gynecologic & Obstetrics

Tuesday, March 1, 2011 9:30 AM

Poster Session III # 211, Tuesday Morning