Computerized Tomography: How Accurate for Abdominal Staging of Testis Tumors?

Abstract

To assess the ability of computerized tomography [CT] to predict correctly the presence of retroperitoneal lymphadenopathy, a prospective study was performed on 39 patients with all stages of testis tumor. All patients underwent a CT scan within 1 wk before retroperitoneal lymphadenectomy and the results then were correlated with gross and histologic findings. The CT scan suggested retroperitoneal lymphadenopathy in 14 patients, in 1 of whom no retroperitoneal lymphadenopathy was found at exploration (false positive, 7%). The sensitivity (CT positive divided by true positive) was 65% and the specificity (CT negative divided by true negative) was 90%, for an over-all accuracy of 73%. Most importantly, however, 7 of the 16 CT scans (44%) interpreted as normal proved to be false negative. Of these 7 scans 5 were in patients with tumors classified as stage B2 or greater. The CT scan, when positive, is highly likely to detect metastatic nodal involvement. The false negative rate, even in patients with tumor-filled lymph nodes 2-3 cm. in diameter, limits the reliability of a negative CT scan to exclude metastases. Technological improvements are needed to refine the technique and, thus, to reduce the false negative rate.