Evaluation of lymph nodes in squamous cell carcinoma of the cervix: touch imprint cytology versus frozen section histology

Metastatic involvement of pelvic lymph nodes (LNs) is the most important negative predictor of survival in early stage cervical cancer. Because the presence of nodal metastases precludes the continuance of any radical surgical procedure, an extraperitoneal LN dissection is performed and LNs are sent for frozen section (FS). As the time for routine FS is about 15 minutes per LN, the use of a faster method, cytology by touch imprint (TI), was investigated. A prospective study was performed to determine the feasibility of TI technique vs. FS. Three hundred eighteen pelvic and para-aortic LNs from 32 patients with cervical cancer of stage I-IV were bisected and submitted for FS after TI had been prepared. Twenty-nine nodes (9.1%) revealed metastatic squamous cell carcinoma (SCC) by frozen section histology. Twenty-six of these were diagnosed by TI and confirmed histologically. Reasons for the 3 false negatives included inadequate preparation or misinterpretation of the TI. Permanent histology always agreed with the frozen section result. Cytologic evaluation of pelvic LNs for SCC at the time of intraoperative consultation had a sensitivity and specificity of 90% and 100%, respectively. Touch imprints may provide a sensitive, specific, and time-efficient method to diagnose nodal metastases in cervical SCC.