Pulmonary lesion after surgery for renal cancer: progression or new primary?

PURPOSE: To investigate clinical and radiological differences between kidney metastases to the lung (RCCM +) and metachronous lung cancer (LC) detected during follow-up in patients surgically treated for Renal Cell Carcinoma (RCC). METHODS: cM0 surgically-treated RCC who harbored a pulmonary mass during follow-up were retrospectively scrutinized. Univariate logistic regression assessed predictive features for differentiating between LC and RCCM + . Multivariable analyses (MVA) were fitted to predict factors that could influence time between detection and histological diagnosis of the pulmonary mass, and how this interval could impact on survivals. RESULTS: 87% had RCCM + and 13% had LC. LC were more likely to have smoking history (75% vs. 29%, p < 0.001) and less aggressive RCC features (cT1-2: 94% vs. 65%, p = 0.01; pT1-2: 88% vs. 41%, p = 0.02; G1-2: 88% vs. 37%, p < 0.001). The median interval between RCC surgery and lung mass detection was longer between LC (55 months [32.8-107.2] vs. 20 months [9.0-45.0], p = 0.01). RCCM + had a higher likelihood of multiple (3[1-4] vs. 1[1-1], p < 0.001) and bilateral (51% vs. 6%, p = 0.002) pulmonary nodules, whereas LC usually presented with a solitary pulmonary nodule, less than 20 mm. Univariate analyses revealed that smoking history (OR:0.79; 95% CI 0.70-0.89; p < 0.001) and interval between RCC surgery and lung mass detection (OR:0.99; 95% CI 0.97-1.00; p = 0.002) predicted a higher risk of LC. Conversely, size (OR:1.02; 95% CI 1.01-1.04; p = 0.003), clinical stage (OR:1.14; 95% CI 1.06-1.23; p < 0.001), pathological stage (OR:1.14; 95% CI 1.07-1.22; p < 0.001), grade (OR:1.15; 95% CI 1.07-1.23; p < 0.001), presence of necrosis (OR:1.17; 95% CI 1.04-1.32; p = 0.01), and lymphovascular invasion (OR:1.18; 95% CI 1.01-1.37; p = 0.03) of primary RCC predicted a higher risk of RCCM + . Furthermore, number (OR:1.08; 95% CI 1.04-1.12; p < 0.001) and bilaterality (OR:1.23; 95% CI 1.09-1.38; p < 0.001) of pulmonary lesions predicted a higher risk of RCCM + . Survival analysis showed a median second PFS of 10.9 years (95% CI 3.3-not reached) for LC and a 3.8 years (95% CI 3.2-8.4) for RCCM + . The median OS time was 6.5 years (95% CI 4.4-not reached) for LC and 6 years (95% CI 4.3-11.6) for RCCM + . CONCLUSIONS: Smoking history, primary grade and stage of RCC, interval between RCC surgery and lung mass detection, and number of pulmonary lesions appear to be the most valuable predictors for differentiating new primary lung cancer from RCC progression.

Long-term functional outcomes in patients undergoing radical nephrectomy for renal cell carcinoma and tumor thrombus.

BACKGROUND: Up to 15% of patients with locally advanced renal cell carcinoma (RCC) harbors tumor thrombus (TT). In those cases, radical nephrectomy (RN) and thrombectomy represents the standard of care. We assessed the impact of TT on long-term functional and oncological outcomes in a large contemporary cohort. METHODS: Within a prospective maintained database, 1207 patients undergoing RN for non-metastatic RCC between 2000 and 2021 at a single tertiary centre were identified. Of these, 172 (14%) harbored TT. Multivariable logistic regression analyses evaluated the impact of TT on the risk of postoperative acute kidney injury (AKI). Multivariable Poisson regression analyses estimated the risk of long-term chronic kidney disease (CKD). Kaplan Meier plots estimated disease-free survival and cancer specific survival. Multivariable Cox regression models assessed the main predictors of clinical progression (CP) and cancer specific mortality (CSM). RESULTS: Patients with TT showed lower BMI (24 vs. 26 kg/m2) and preoperative Hb (11 vs. 14 g/mL; all-p < 0.05). Clinical tumor size was higher in patients with TT (9.6 vs. 6.5 cm; p < 0.001). After adjusting for potential confounders, the presence of TT was significantly associated with a higher risk of postoperative AKI (OR 2.03, 95% CI 1.49-3.6; p < 0.001) and long-term CKD (OR: 1.32, 95% CI 1.10-1.58; p < 0.01). Notably, patients with TT showed worse long-term oncological outcomes and TT was a predictor for CP (2.02, CI 95% 1.49-2.73, p < 0.001) and CSM (HR 1.61, CI 95% 1.04-2.49, p < 0.03). CONCLUSIONS: The presence of TT in RCC patients represents a key risk factor for worse perioperative, as well as long-term renal function. Specifically, patients with TT harbor a significant and early estimated glomerular filtration rate (eGFR) decrease. However, despite TT patients show a greater eGFR decline after surgery, they retain acceptable renal function, which remains stable over time.