Staging and Surveillance of Testicular Cancer CT Abdomen and Pelvis CT is the reference standard imaging test used for assessing the retroperitoneum for the presence of metastatic lymphadenopathy. CT is rapid, reproducible, and provides excellent imaging assessment of the para-aortic and paracaval regions [13-15]. Challenges related to CT are that many young men have little retroperitoneal fat, which may be an impediment for readers interpreting the study, and that CT cannot detect metastatic disease in lymph nodes of normal size. Additionally, inflammatory lymph nodes cannot be differentiated from those that are enlarged from metastases [16]. Lymph nodes >1 cm in short axis are highly suspicious for metastatic disease, particularly if they are located in the hilar regions of the kidney or in the para-aortic or caval areas (eg, testicular cancer landing zones). Various studies have established the accuracy of CT in detecting metastatic retroperitoneal lymph nodes from testicular cancer, which ranges from 73% to 97%, sensitivity ranges from 65% to 96%, and specificity from 81% to 100% [7,17-22]. Data also indicate that the accuracy of CT declines in patients with limited disease (eg, stage N1 and stage N2) and also if the upper limit of normal lymph node size is lowered [15,17,21]. Of note, most of these studies are relatively old and were performed using single-slice CT; however, limited newer data suggest similar accuracy using multi- slice CT compared with single-slice CT [23]. It is important to recognize that a significant percentage of metastatic lymph nodes will be <1 cm, up to 60% in one series [24]. For this reason, some authors suggest using a cut-off value of 0.7 cm to 0.8 cm in testicular cancer at the expense of reduced specificity [24,25].
Staging and Surveillance of Testicular Cancer. Staging and Surveillance of Testicular Cancer CT Abdomen and Pelvis CT is the reference standard imaging test used for assessing the retroperitoneum for the presence of metastatic lymphadenopathy. CT is rapid, reproducible, and provides excellent imaging assessment of the para-aortic and paracaval regions [13-15]. Challenges related to CT are that many young men have little retroperitoneal fat, which may be an impediment for readers interpreting the study, and that CT cannot detect metastatic disease in lymph nodes of normal size. Additionally, inflammatory lymph nodes cannot be differentiated from those that are enlarged from metastases [16]. Lymph nodes >1 cm in short axis are highly suspicious for metastatic disease, particularly if they are located in the hilar regions of the kidney or in the para-aortic or caval areas (eg, testicular cancer landing zones). Various studies have established the accuracy of CT in detecting metastatic retroperitoneal lymph nodes from testicular cancer, which ranges from 73% to 97%, sensitivity ranges from 65% to 96%, and specificity from 81% to 100% [7,17-22]. Data also indicate that the accuracy of CT declines in patients with limited disease (eg, stage N1 and stage N2) and also if the upper limit of normal lymph node size is lowered [15,17,21]. Of note, most of these studies are relatively old and were performed using single-slice CT; however, limited newer data suggest similar accuracy using multi- slice CT compared with single-slice CT [23]. It is important to recognize that a significant percentage of metastatic lymph nodes will be <1 cm, up to 60% in one series [24]. For this reason, some authors suggest using a cut-off value of 0.7 cm to 0.8 cm in testicular cancer at the expense of reduced specificity [24,25].