Baseline characteristics. Between 2011 and 2020, 173 patients with distal ureteral urothelial carcinoma (UC) were enrolled. Among them, 127 patients underwent RNU and 46 patients underwent elective DU for UTUC in the distal ureter. As shown in Table 1, more patients who underwent RNU had diabetes mellitus as the underlying disease (p = 0.042). There were differences in the year of surgery (p < 0.001) and surgical approach (p < 0.001), but there were no differences in other baseline characteristics between the two groups (p > 0.05). The tumor size in the DU group was smaller than that in RNU group (3.1 ± 1.8 vs. 1.7 ± 1.0 cm, p < 0.001). Pathological characteristics, including T stage, tumor grade, concomitant lymphovascular invasion (LVI), lymph node (LN) stage, and margin status, were not significantly different between the groups (p > 0.05).
Table 1
Baseline characteristics between the RNU and DU groups.
| RNU group (n = 127) | DU group (n = 46) | p-value |
No. of patients | 127 | 46 | |
Age, year | 66.8 ± 9.6 | 64.8 ± 9.9 | 0.226 |
Sex, male, % | 98 (77.2) | 39 (84.8) | 0.276 |
Body mass index | 24.0 ± 2.9 | 24.5 ± 3.2 | 0.372 |
DM, % | 39 (30.7) | 7 (15.2) | 0.042 |
HTN, % | 59 (46.5) | 22 (47.8) | 0.873 |
Year of surgery, % | | | < 0.001 |
2011–2014 | 49 (38.6) | 11 (23.9) | |
2015–2017 | 29 (22.8) | 25(54.3) | |
2018–2020 | 49 (38.6) | 10 (21.7) | |
History of previous bladder cancer, % | 34 (26.8) | 14 (30.4) | 0.637 |
Approach type of surgery, % | | | < 0.001 |
Open | 32 (25.2) | 27 (58.7) | |
Laparoscopic | 81 (63.8) | 0 (0) | |
Robot-assisted | 14 (11.0) | 19 (41.3) | |
Pathologic data | | | |
Pathological T stage, % | | | 0.480 |
Tis | 2 (1.6) | 3 (6.5) | |
Ta | 15 (11.8) | 11 (23.9) | |
T1 | 33 (26.0) | 9 (19.6) | |
T2 | 32 (25.2) | 12 (26.1) | |
T3 | 45 (35.4) | 11 (23.9) | |
Tumor grade | | | 0.100 |
I, II | 55 (43.3) | 25 (54.3) | |
III | 71 (55.9) | 18 (39.1) | |
Concomitant LVI | 20 (15.7) | 5 (10.9) | 0.420 |
Pathological N stage, % | | | 0.186 |
Nx/N0 | 116 (91.3) | 45 (97.8) | |
≥N1 | 11 (8.7) | 1 (2.2) | |
Margin positive, % | 5 (3.9) | 0 (0) | 0.326 |
Tumor size, cm | 3.1 ± 1.8 | 1.7 ± 1.0 | < 0.001 |
Follow-up duration, months | 53.3 ± 34.8 | 39.8 ± 21.4 | 0.003 |
Progression patterns between RNU and DU. There was no significant difference in progression patterns between the two groups (p = 0.441). Progression occurred in 35 patients (27.6%) in the RNU group and in 10 patients (21.7%) in the DU group. The most common site of progression was the lymph nodes in both groups (77.1% of the RNU group vs. 50% of the DU group). The pelvic cavity (31.4%), lung (20%), bone (11.4%), and liver (5.78%) followed in the RNU group. The lungs (20%), pelvic cavity (10%), and liver (10%) followed in the DU group (Table 2).
Table 2
Progression pattern between the RNU and DU groups.
| RNU group (n = 127) | DU group (n = 46) | p-value |
Progression | 35 (27.6) | 10 (21.7) | 0.441 |
Lymph node | 27 (77.1) | 5 (50) | |
Pelvic cavity | 11 (31.4) | 1 (10) | |
Lung | 7 (20.0) | 2 (20) | |
Bone | 4 (11.4) | 0 (0) | |
Liver | 2 (5.7) | 1 (10) | |
Kidney | 0 (0) | 1 (10) | |
Adrenal gland | 1 (2.9) | 0 (0) | |
Pancreas | 1 (2.9) | 0 (0) | |
Colon | 1 (2.9) | 0 (0) | |
Penis | 0 (0) | 1 (10) | |
Vagina | 1 (2.9) | 0 (0) | |
Multiple metastasis | 13 (37.1) | 1 (10) | |
Oncological outcomes including PFS, OS, CSS, and IVRFS between RNU and DU. The 3-year PFS rates in the RNU and DU groups were 73.5% and 79.8%, respectively (p = 0.736; Fig. 1A). There were also no statistically significant differences in the 3-year OS and CSS rates between patients treated with RNU and DU (83.1% vs. 88.8%, p = 0.457, Fig. 1B; 93.6% vs. 91.2%, p = 0.169, Fig. 1C; respectively). There were no statistically significant differences in the 3-year IVRFS between patients treated with RNU and DU (54.5% vs. 50.4%, p = 0.921, Fig. 1D).
Progression factors following surgery. Univariate analysis showed that the risk factors for progression after surgery included ≥ pT2, tumor grade III, concomitant LVI, and lymph node involvement (Hazard ratio (HR) 9.067, p < 0.001; HR 3.339, p = 0.002; HR 11.524, p < 0.001; and HR 41.088, p < 0.001, respectively). Independent predictors of progression in multivariate analysis were ≥ pT2, concomitant LVI, and LN involvement (HR 5.350, p = 0.005; HR 4.793, p = 0.006; and HR 23.454, p = 0.006, respectively). The surgical approach was not associated with progression (Table 3).
Table 3
Variables associated with risk of progression following surgery for distal ureter UC.
| Univariate | Multivariate |
| HR | 95% CI | p-value | HR | 95% CI | p-value |
Age at surgery | 0.971 | 0.938–1.006 | 0.102 | | | |
HTN | 0.778 | 0.392–1.544 | 0.473 | | | |
DM | 1.220 | 0.571–2.606 | 0.608 | | | |
BMI | 0.994 | 0.885–1.116 | 0.916 | | | |
Prev. Bladder Ca | 0.571 | 0.251–1.298 | 0.181 | | | |
T stage | | | | | | |
<pT2 | Ref | | | Ref | | |
≥pT2 | 9.067 | 3.361–24.459 | < 0.001 | 5.350 | 1.644–17.416 | 0.005 |
Tumor grade | | | | | | |
I, II | Ref | | | Ref | | |
III | 3.339 | 1.578–7.065 | 0.002 | 0.907 | 0.336–2.445 | 0.847 |
Concomitant LVI | 11.524 | 4.379–30.326 | < 0.001 | 4.793 | 1.585–14.493 | 0.006 |
N+ | 41.088 | 5.124–329.484 | < 0.001 | 23.454 | 2.504–219.701 | 0.006 |
Margin | 1.922 | 0.311–11.895 | 0.482 | | | |
Tumor size | 1.091 | 0.906–1.312 | 0.358 | | | |
Surgical approach | | | | | | |
RNU | Ref | | | Ref | | |
DU | 0.730 | 0.328–1.627 | 0.442 | 1.060 | 0.410–2.741 | 0.905 |
Upper tract recurrence pattern in patients with DU. Among 46 patients treated with DU, nine (19.6%) had recurred ipsilateral ureter or renal pelvis tumor during F/U duration of mean 18.3 ± 12.7 months. Of the nine patients, six (66.7%) had a prior history of bladder tumor. All patients underwent salvage RNU. Individual information regarding upper tract recurrence and management in the DU group is shown in Supplementary Table 1. In the univariate analysis, histories of bladder cancer history (HR 5.4, p = 0.035) and CIS (HR 18.000, p = 0.019) were significant predictors of upper tract recurrence following DU for distal ureteral cancer. However, in the multivariate analysis, there were no significant predictors of upper tract recurrence.
Oncological outcomes including PFS, OS, CSS, and IVRFS between RNU, DU and DU with upper tract recurrence followed by salvage RNU. The 3-year PFS rates were 73.5%, 76.8%, and 90.0% in the RNU, DU without upper tract recurrence, and DU with upper tract recurrence followed by salvage RNU groups, respectively, which were not significantly different (p = 0.936, Fig. 2A). There were also no statistically significant differences in the 3-year OS and CSS rates among the three groups (83.1% vs. 88.6% vs. 88.9%, p = 0.673, Fig. 2B; 93.6% vs. 91.9% vs. 88.9%, p = 0.223, Fig. 2C; respectively). There were no statistically significant differences in 3-year IVRFS among patients treated with RNU, DU, or DU with upper tract recurrence, followed by salvage RNU (54.5% vs. 50.9% vs. 50.0%, p = 0.829, Fig. 2D).
Functional outcomes between RNU and DU. Supplementary Table 2 shows the changes in eGFR in the RNU and DU groups. As expected, patients treated with elective DU had significantly better eGFR preservation than those treated with RNU at 1, 3, and 6 months, and 1 year postoperatively (all p < 0.001).