Telomerase activity predicts malignancy in percutaneous image-guided needle biopsy specimens of the abdomen and pelvis

PURPOSE: To determine prospectively if assessment of telomerase activity in percutaneous needle biopsy specimens improves sensitivity and specificity in the diagnosis of abdominal and pelvic malignancy. MATERIALS AND METHODS: The study was approved by the institutional review board, and written informed consent was obtained from all patients. A prospective double-blinded design was used to assess telomerase activity in abdominal and pelvic biopsy specimens from 99 patients (64 men, 35 women; age range, 22-87 years). After the clinical sample was retrieved, a study specimen from an extra needle pass was divided and independently analyzed for cytologic characteristics and telomerase activity. The final diagnosis was based on chart review at a minimum 1-year follow-up. Statistical analyses included sensitivity, specificity, and accuracy of cytologic examination and/or telomerase activity in predicting malignancy. RESULTS: Data from study specimens indicated that the sensitivity, specificity, and accuracy of telomerase activity (n = 99) in predicting malignancy were 55%, 79%, and 60%, respectively. For cytologic examination (n = 86), the sensitivity, specificity, and accuracy in predicting malignancy were 74%, 94%, and 78%, respectively. Combining the two tests (n = 86) and classifying a positive reading with either test as malignant improved sensitivity (83%) (P < .05) without altering specificity (76%). In 20 patients who had clinical sample reports that were classified as indeterminate, telomerase activity (n = 20) yielded a higher sensitivity (62%) (P < .05) and similar specificity (86%) compared with cytologic examination (n = 15), which yielded a sensitivity of 11% and a specificity of 83%. CONCLUSION: In percutaneous biopsy specimens of the abdomen and pelvis, the combination of cytologic examination and telomerase activity yielded an increased sensitivity in predicting malignancy. In addition, assessing telomerase activity can help identify cancer even when cytologic results are indeterminate. (C) RSNA, 2005.