The clinical implications of hydronephrosis and the level of ureteral obstruction in stage IIIB cervical cancer.

PURPOSE: There are two criteria for the diagnosis of Stage IIIB cervical cancer in the FIGO staging system: tumor fixation to the pelvic side wall and/or the presence of hydronephrosis due to tumor. However, we often encounter hydronephrosis without tumor fixed to the pelvic side wall or the level of ureteral obstruction not corresponding to the main tumor mass in the pelvis. The clinical implication of these phenomena remains unclear. We investigated the Stage IIIB population treated at the Mallinckrodt Institute of Radiology and hypothesized that, if hydronephrosis presents without tumor fixation to the pelvic side wall or if the level of ureteral obstruction is above the main pelvic tumor mass, it most likely resulted from external compression of ureter(s) by enlarged lymph nodes and, consequently, a worse outcome is expected. METHODS AND MATERIALS: From 1959 to 1989, there were 297 patients with Stage IIIB cervical cancer who received definitive radiation therapy at the Mallinckrodt Institute of Radiology and were assessable for the presence of hydronephrosis and the level of ureteral obstruction. There were 281 patients who presented with tumor fixed to the pelvic side wall, and 62 of them were associated with concurrent hydronephrosis. An additional 16 patients presented with hydronephrosis without tumor fixation to the pelvic side wall. Among these 78 documented cases of hydronephrosis, the level of ureteral obstruction was above the true pelvis in 39 patients, and below the true pelvis in the other 39. Radiation therapy was individualized according to tumor extension and configuration; para-aortic lymph nodes were not routinely treated except in patients with clinical evidence of nodal metastasis.
RESULTS: The progression-free survival (PFS) at 5 years was 35% in 62 patients with hydronephrosis and tumor fixed to the pelvic side wall vs. 43% in 213 patients with tumor fixed to the pelvic side wall only (p=0.12). However, PFS at 5 years decreased to 23% in 16 patients who presented with hydronephrosis without tumor fixation to the pelvic side wall (p < 0.001). When the level of ureteral obstruction was investigated, 5-year PFS was 39% vs. 22%, respectively, for the obstruction below vs. above the true pelvis (p=0.02). The majority of patients with ureteral obstruction above the true pelvis died of distant metastasis.
CONCLUSIONS: The additional presence of hydronephrosis did not significantly worsen the PFS among Stage IIIB patients with tumor fixation to the pelvic side wall. However, hydronephrosis without tumor extending to the pelvic side wall or the level of ureteral obstruction above the true pelvis was associated with poor outcome due to a significant increase in distant failure. We propose that this population be separated from current Stage IIIB classification.