Impact of body composition on outcomes of immune checkpoint inhibitor combination therapy in patients with previously untreated advanced renal cell carcinoma.

BACKGROUND: Data on the association between body composition and outcomes in patients with advanced renal cell carcinoma (RCC) treated with immune checkpoint inhibitor (ICI) combination therapy are limited. METHODS: We retrospectively evaluated the clinical and radiographic data of 159 patients with advanced RCC, including 84 receiving ICI dual combination therapy (immunotherapy [IO]-IO group) and 75 receiving combinations of ICIs with tyrosine kinase inhibitors (TKIs) (IO-TKI group). Pretreatment computed tomography images were used to calculate body composition, including skeletal muscle mass and fat tissue area. Sarcopenia was defined based on skeletal muscle and psoas muscle indexes. The total fat index, subcutaneous fat index (SFI), and visceral fat index were also calculated. RESULTS: In the IO-IO treatment group, there was no significant association between body composition and survival or tumor response (P > 0.05). In the IO-TKI treatment group, the high SFI was associated with longer progression-free survival (hazard ratio, 2.70; P = 0.0091) and overall survival (hazard ratio, 26.0; P = 0.0246) than the low SFI, which remained significant after adjusting for covariates. Furthermore, in the high-SFI population, patients treated with IO-TKI therapy had longer progression-free survival (P = 0.0019) and overall survival (P = 0.0287) than those treated with IO-IO therapy, while there was no significant survival difference between the 2 treatment groups in the low-SFI population (P > 0.05). CONCLUSION: The SFI can be potentially utilized as an effective predictive and prognostic biomarker for first-line ICI combination therapy for advanced RCC.

Renal outcome of living kidney donors aged more than 70 years.

BACKGROUND: The number of marginal living kidney donors has increased. Medically complex donors who have hypertension, older age, or low estimated glomerular filtration rate (eGFR) have been more likely to be used. METHODS: We conducted a retrospective cohort study of living kidney donors at a single center. We analyzed 309 living donors and divided them into three groups: group with older donors (aged ≥70 years) (n = 41), middle-aged (aged 46-69 years) (n = 239), and young donors (aged <46 years) (N = 29). Donor factors associated with chronic kidney disease (CKD) stage 3b or worse within 5 years post-donation were investigated. RESULTS: Of the 309 live donors, 86 (27.8%) developed CKD stage3b or worse within 5 years post-donation. The incidence of CKD stage3b or worse within 5 years post-donation was significantly higher in older donor (p < 0.01). Cox regression models revealed that older donor ages and lower eGFR were significantly related to the development of CKD stage3b or worse, independent of comorbidities such as obesity and hypertension [hazard ratio (95% CI); 4.59 (1.02-20.6), p = 047, 0.95 (0.94-0.96), p ≤ 0.01, respectively]. However, recovery of eGFR 4-5 years after donation was noted in the middle-aged and older donor groups, whereas the level of eGFR remained unchanged in the young group. CONCLUSIONS: Older donors tend to develop CKD stage3b within 5 years post-donation but with the potential of recovery. Healthy older people (aged ≥70 years) could be candidates for living donors under careful monitoring of kidney function after donation.

Safety of Docetaxel in a Patient with Metastatic Castration-Resistant Prostate Cancer After Kidney Transplantation: A Case Report.

BACKGROUND: There are limitations in treating advanced prostate cancer (PC), especially castration-resistant (CR) cases, in renal transplant recipients (RTRs). We describe the case of RTR with metastatic CRPC (mCRPC) treated with docetaxel. CASE REPORT: A 60-year-old man with end-stage renal disease due to autosomal-dominant polycystic kidney disease (ADPKD) underwent living-related kidney transplantation. A year later, he was diagnosed with PC (prostate-specific antigen level: 998 ng/mL). Prostate biopsy revealed prostatic adenocarcinoma with a Gleason score of 4 + 4 = 8. Radiographic examination revealed seminal vesicle invasion and multiple bone and lymph node metastases. Combined androgen blockade therapy was initiated; however, the patient was diagnosed with CRPC 6 months later. Triweekly docetaxel therapy was administered 28 months after diagnosis. The patient successfully completed 7 cycles of this therapy without major adverse events. However, after the 7th cycle, he developed a high fever caused by an infection of ADPKD-associated renal cysts. Therefore, docetaxel was discontinued, and enzalutamide was started, followed by abiraterone, but without any effect. We then introduced cabazitaxel but discontinued it because of hepatic dysfunction. Hence, the patient underwent a docetaxel rechallenge. He was administered the PEGylated form of the recombinant human granulocyte colony-stimulating factor for neutropenia prophylaxis. After 6 cycles of rechallenge docetaxel therapy, the patient accidentally fell, resulting in a cervical spine fracture and subsequent death due to respiratory failure. CONCLUSIONS: Docetaxel can be safely delivered to patients with CRPC after renal transplantation who are taking oral immunosuppressants. It can be a good treatment option for them.

En bloc kidney transplantation from pediatric donors to teenage recipients: Two case reports.

Introduction: Since the implementation of the new selection criteria in 2018, kidney donations from pediatric patients have been prioritized for pediatric recipients and kidney donations from pediatric donors have increased in Japan. Herein, we present two cases of en bloc kidney transplantation. Case presentation: Case 1: A 19-year-old male patient who had been on hemodialysis for 5 years due to end-stage renal disease. After brain death, a graft from a 5-year-old boy was transplanted into the right iliac fossa. Case 2: A 19-year-old male patient, who had previously undergone a living kidney transplantation at the age of 3, received a secondary cadaveric kidney transplantation in the left iliac fossa. The graft was procured from a 17-month-old girl following cardiac death. Conclusion: This report will help surgeons perform en bloc kidney transplantation in the growing number of pediatric kidney donations, such as those in Japan.

First-line dual immune checkpoint inhibitor therapies versus combination therapies comprising immune checkpoint inhibitors and tyrosine kinase inhibitors for advanced renal cell carcinoma: a comparative analysis of the effectiveness using real-world data.

BACKGROUND: There are few comparative studies on dual immune checkpoint inhibitors (ICIs) (i.e., IO-IO) and combination therapies comprising ICIs plus tyrosine kinase inhibitors (TKIs) (i.e., IO-TKI) for advanced renal cell carcinoma (RCC), especially in real-world settings. METHODS: We retrospectively evaluated data of 175 patients with IMDC intermediate-risk or poor-risk RCC; as first-line therapy, 103 received IO-IO, and 72 received IO-TKI. An inverse probability of treatment weighting (IPTW) analysis was conducted to balance patients' backgrounds in the IO-IO and IO-TKI groups. RESULTS: Based on the IPTW analysis, progression-free survival (PFS) was longer in the IO-TKI group than in the IO-IO group (median: 15.6 vs. 8.3 months; p = 0.0386). In contrast, overall survival was not different between groups (median: 46.7 vs. 49.0 months; p = 0.465). Although the IPTW-adjusted objective response rate was not significantly different (51.2% vs. 43.9%; p = 0.359), the progressive disease rate as the best overall response was lower in the IO-TKI group than in the IO-IO group (3.3% vs. 27.4%; p < 0.0001). Regarding the safety profile, the treatment interruption rate was higher in the IO-TKI group than in the IO-IO group (70.3% vs. 49.2%; p = 0.005). In contrast, the IO-IO group had a higher corticosteroid administration rate (43.3% vs. 20.3%; p = 0.001). CONCLUSION: IO-TKI therapy exhibited superior effectiveness over IO-IO therapy in terms of PFS improvement and immediate disease progression prevention and was associated with a higher risk of treatment interruption and a lower risk of needing corticosteroids.

Advanced Renal Cell Carcinoma With Inferior Vena Cava Thrombus Treated With a Combination of Preoperative Lenvatinib and Pembrolizumab.

BACKGROUND/AIM: Lenvatinib plus pembrolizumab combination therapy is a safe and effective treatment for patients with advanced renal cell carcinoma (RCC). However, there are no reports of the use of lenvatinib and pembrolizumab combination therapy for RCC with an inferior vena cava (IVC) tumor thrombus. Herein, we describe a case in which pembrolizumab and lenvatinib combination therapy was effectively used to treat RCC with the IVC tumor thrombus extending to the right atrium. CASE REPORT: A 73-year-old man was diagnosed with a right renal tumor with the IVC tumor thrombus extending to the right atrium and multiple pulmonary metastases (cT3cN0M1). Using a computed tomography-guided renal tumor biopsy, the tumor was diagnosed as clear cell RCC. The International Metastatic RCC Database Consortium risk classification was poor according to three risk factors, and lenvatinib and pembrolizumab combination therapy was initiated. The primary renal tumor shrunk, the IVC tumor thrombus that reached the right atrium was reduced from level 4 to level 2, and the lung metastases disappeared 4 months after treatment initiation. Thereafter, a robot-assisted deferred cytoreductive nephrectomy was successfully performed. Pathologically, owing to the preoperative combination therapy, most of the tumor tissue was necrotic; however, some viable cells were present in the primary tumor and IVC tumor thrombus. Eight months following the operation, the patient remains recurrence-free. CONCLUSION: Treatment with lenvatinib and pembrolizumab combination therapy led to tumor shrinkage and allowed robot-assisted nephrectomy in a patient with advanced RCC with the IVC tumor thrombus extending to the right atrium, corroborating the efficacy of the treatment.

Higher Donor Age and Severe Microvascular Inflammation Are Risk Factors for Chronic Rejection After Treatment of Active Antibody-Mediated Rejection.

Recent developments in intensive desensitization protocols have enabled kidney transplantation in human leukocyte antigen (HLA)-sensitized recipients. However, cases of active antibody-mediated rejection (AABMR), when they occur, are difficult to manage, graft failure being the worst-case scenario. We aimed to assess the impact of our desensitization and AABMR treatment regimen and identify risk factors for disease progression. Among 849 patients who underwent living-donor kidney transplantation between 2014 and 2021 at our institution, 59 were diagnosed with AABMR within 1 year after transplantation. All patients received combination therapy consisting of steroid pulse therapy, intravenous immunoglobulin, rituximab, and plasmapheresis. Multivariable analysis revealed unrelated donors and preformed donor-specific antibodies as independent risk factors for AABMR. Five-year death-censored graft survival rate was not significantly different between patients with and without AABMR although 27 of 59 patients with AABMR developed chronic AABMR (CABMR) during the study period. Multivariate Cox proportional hazard regression analysis revealed that a donor age greater than 59 years and microvascular inflammation (MVI) score (g + ptc) ≥4 at AABMR diagnosis were independent risk factors for CABMR. Our combination therapy ameliorated AABMR; however, further treatment options should be considered to prevent CABMR, especially in patients with old donors and severe MVI.

Metabolic and Epigenetic Reprogramming in a Case of Nuclear Protein in Testis (NUT) Carcinoma of the Retroperitoneum.

Nuclear protein in testis (NUT) carcinoma is a rare but highly aggressive carcinoma, driven by genetic rearrangement of the NUT midline carcinoma family member 1 (NUTM1) gene on chromosome 15q14. Recently, a tight link has been suggested between genetic abnormalities and subsequent metabolic and epigenetic dysregulation to drive the progression of malignant tumors. However, it remains elusive whether such reprogramming could contribute to the pathogenesis of NUT carcinoma. We herein report an autopsy case of NUT carcinoma arising in the retroperitoneum of a 31-year-old male. Notably, reprogramming of glycolytic metabolism and epigenetic histone modifications was observed in this unusual NUT carcinoma case, and this phenomenon was further confirmed by an in vitro cell culture model with bromodomain containing 4 (BRD4)-NUT overexpression. The rationale for documenting the case is based on our findings to reveal that metabolic and epigenetic reprogramming could be one of the contributing factors to the pathogenesis of NUT carcinoma, which could be exploitable as a novel therapeutic target for this rare and aggressive cancer type.

Prognostic Value of the Lung Immune Prognostic Index on Recurrence after Radical Surgery for High-Risk Renal Cell Carcinoma.

With emerging options in immediate postoperative settings for high-risk renal cell carcinoma (hrRCC), further risk stratification may be relevant for informed decision making. Balancing the benefits and drawbacks of adjuvant immunotherapy is recommended. We aimed to evaluate the effects of the lung immune prognostic index (LIPI) in this setting. This bi-institutional retrospective study recruited 235 patients who underwent radical surgery for hrRCC between 2004 and 2021. LIPI scores were calculated based on the derived neutrophil-to-lymphocyte ratio and lactate dehydrogenase levels. The association between LIPI scores and local or distant recurrence was analyzed, along with other possible clinical factors. The median recurrence-free survival (RFS) period was 36.4 months. Based on the LIPI scores, 119, 91, and 25 patients were allocated to the good, intermediate, and poor groups, respectively. The RFS was significantly correlated with the LIPI scores, and the 36 month survival rates were 67.3, 36.2, and 11.0% in the good, intermediate, and poor groups, respectively. In the multivariate model, the LIPI independently predicted the RFS, along with symptoms at diagnosis, Eastern Cooperative Oncology Group performance status, pT status, pN status, and tumor grade. The C-index of the LIPI in predicting RFS was 0.63, and prediction accuracy improved with the addition of the LIPI to both GRade, Age, Nodes, Tumor, and the UCLA Integrated Staging System. Conclusively, the LIPI can be a significant prognostic biomarker for predicting hrRCC recurrence, particularly for identifying the highest-risk cohort.

Lenvatinib Plus Pembrolizumab Versus Sunitinib in First-Line Treatment of Advanced Renal Cell Carcinoma: Final Prespecified Overall Survival Analysis of CLEAR, a Phase III Study.

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical trial updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported.We present the final prespecified overall survival (OS) analysis of the open-label, phase III CLEAR study in treatment-naïve patients with advanced renal cell carcinoma (aRCC). With an additional follow-up of 23 months from the primary analysis, we report results from the lenvatinib plus pembrolizumab versus sunitinib comparison of CLEAR. Treatment-naïve patients with aRCC were randomly assigned to receive lenvatinib (20 mg orally once daily in 21-day cycles) plus pembrolizumab (200 mg intravenously once every 3 weeks) or sunitinib (50 mg orally once daily [4 weeks on/2 weeks off]). At this data cutoff date (July 31, 2022), the OS hazard ratio (HR) was 0.79 (95% CI, 0.63 to 0.99). The median OS (95% CI) was 53.7 months (95% CI, 48.7 to not estimable [NE]) with lenvatinib plus pembrolizumab versus 54.3 months (95% CI, 40.9 to NE) with sunitinib; 36-month OS rates (95% CI) were 66.4% (95% CI, 61.1 to 71.2) and 60.2% (95% CI, 54.6 to 65.2), respectively. The median progression-free survival (95% CI) was 23.9 months (95% CI, 20.8 to 27.7) with lenvatinib plus pembrolizumab and 9.2 months (95% CI, 6.0 to 11.0) with sunitinib (HR, 0.47 [95% CI, 0.38 to 0.57]). Objective response rate also favored the combination over sunitinib (71.3% v 36.7%; relative risk 1.94 [95% CI, 1.67 to 2.26]). Treatment-emergent adverse events occurred in >90% of patients who received either treatment. In conclusion, lenvatinib plus pembrolizumab achieved consistent, durable benefit with a manageable safety profile in treatment-naïve patients with aRCC.

The medical cost and outcome of desensitization protocol in kidney transplantation recipients with high immunological risks.

BACKGROUND: Kidney transplantation is a well-established alternative in renal replacement therapy. Compared with hemodialysis, low-immunological-risk kidney transplantation can reduce the medical treatment costs associated with end-stage renal disease. However, there are few reports on whether high-immunological-risk kidney transplantation reduces the financial burden on governments. We investigated the medical costs of high-immunological-risk kidney transplantation in comparison with the cost of hemodialysis in Japan. METHODS: We compared the medical costs of high-immunological-risk kidney transplantation with those of hemodialysis. 15 patients who underwent crossmatch-positive and/or donor-specific antibody-positive kidney transplantations between 2020 and 2021 were enrolled in this study. The patients received intravenous immunoglobulin, plasmapheresis, and rituximab as desensitizing therapy. RESULTS: Acute antibody-mediated rejection was detected in nine (60%) recipients, while there were no indications of graft function deterioration during the follow-up. For each patient, the transplant hospitalization cost was 38 428 ± 8789 USD. However, the cumulative costs were 59 758 ± 10 006 USD and 79 781 ± 16 366 USD, at 12 and 24 months, respectively. Compared with hemodialysis (34 286 USD per year), high-immunological-risk kidney transplantation tends to be expensive in the first year, but the cost is likely to be lower than that of hemodialysis after 3 years. CONCLUSIONS: Although kidney transplantation is initially expensive compared with hemodialysis, the medical cost becomes advantageous after 3 years even in kidney transplant recipients with high immunological risk.

Comparisons of survival and surgical outcomes between minimally invasive partial nephrectomy and radical nephrectomy in elderly patients with stage 1 renal cell carcinoma.

AIM: We compared survival and perioperative outcomes of robot-assisted laparoscopic partial nephrectomy (RAPN) and laparoscopic radical nephrectomy (LRN) for older patients (age 70 years or older) with stage 1 renal cell carcinoma (RCC). METHODS: This retrospective, single-center study included 260 patients who underwent RAPN and 44 patients who underwent LRN. The overall survival (OS) and perioperative outcomes were compared between these two groups using an inverse probability of treatment weighting (IPTW) analysis. RESULTS: Compared with the LRN group, a trend of more complications was observed in the RAPN group, including a higher body mass index (24 vs. 22 kg/m2 ; P = 0.0002) and higher rates of hypertension (77% vs. 55%; P = 0.0029) and chronic kidney disease (62% vs. 36%; P = 0.0027). After adjustment by the IPTW analysis, the RAPN group had a shorter operative time (143 vs. 282 min; P = 0.033), shorter postoperative length of hospital stay (PLOS) (4.1 vs. 7.9 days; P = 0.004), and less change in the estimated glomerular filtration rate during surgery (-8.4% vs. -32%; P < 0.0001) than the LRN group; however, the perioperative complication rates were similar. Patients who underwent RAPN had better 5-year OS than those who underwent LRN (95% vs. 90%; log-rank, P = 0.017). CONCLUSION: RAPN resulted in better OS and surgical outcomes, with shorter operative time, shorter PLOS, and better renal function preservation, than LRN for older patients with stage 1 RCC. Therefore, RAPN may be the primary option for patients indicated for surgical intervention. Geriatr Gerontol Int 2024; 24: 269-274.

Association Between Kidney Function and Outcomes Following Immune Checkpoint Inhibitor-Based Combination Therapy in Patients With Advanced Renal Cell Carcinoma.

BACKGROUND: It remains unclear whether kidney function affects outcomes following immune checkpoint inhibitor (ICI)-based combination therapy for advanced renal cell carcinoma (RCC). METHODS: We retrospectively evaluated data of 167 patients with advanced RCC, including 98 who received ICI dual combination therapy (ie, immunotherapy [IO]-IO) and 69 who received ICI combined with tyrosine kinase inhibitor (TKI) (ie, IO-TKI). In each regimen, treatment profiles were assessed according to the grade of chronic kidney disease (CKD) as defined by the KDIGO 2012 criteria. RESULTS: Of the 98 patients who received IO-IO, 31 (32%), 30 (31%), 15 (15%), and 22 (22%) had CKD G1/2, G3a, G3b, and G4/5, respectively. Of the 69 patients who received IO-TKI, 18 (26%), 25 (36%), and 26 (38%) had G1/2, G3a, and G3b/4/5, respectively. Regarding efficacy, progression-free survival, overall survival, or objective response rate was not different according to the CKD grade in both treatment groups (P > .05). Regarding safety, the rate of adverse events, treatment interruption, or corticosteroid administration was not different according to the CKD grade in the IO-IO group (P > .05), whereas in the IO-TKI group, the incidence of grade ≥ 3 adverse events were significantly higher (P = .0292), and the rates of ICI interruption (P = .0353) and corticosteroid administration (P = .0685) increased, according to the CKD grade. CONCLUSION: There is a differential safety but comparable efficacy profile between the IO-IO and IO-TKI regimens in patients with CKD. Further prospective studies are required to confirm these findings.

Predicting Recurrence After Radical Surgery for High-Risk Renal Cell Carcinoma: Development and Internal Validation of the "TOWARDS" Score.

BACKGROUND: Considering the reported greater benefits of immunotherapy and its unignorable adverse events in adjuvant therapy for high-risk renal cell carcinoma (hrRCC), accurate prediction may optimize drug use. METHODS: The primary objective of this study was to generate a score-based prognostic model of recurrence-free survival in hrRCC. The study retrospectively evaluated 456 patients at two institutions who underwent radical surgery for nonmetastatic pT3-4 and/or N1-2 or pT2 and G4 disease. Clinical variables deemed universally available were selected through backward stepwise analysis and fitted by a multivariable Cox proportional hazards regression model. A point-based score was derived from regression coefficients. Discrimination, calibration, and decision curve analyses were conducted to evaluate predictive performance. Internal validation with bootstrapping was performed to correct for optimism. RESULTS: The mean follow-up period was 55.3 months, and the median follow-up period was 28.0 months. During the follow-up period, the recurrence rate was 48.2% (n = 220) during a median of 75.7 months. Stepwise variable selection retained age, Eastern Cooperative Oncology Group (ECOG) performance status, presence or absence of symptoms, size of the primary tumor, pathologic T stage, pathologic N stage, tumor grade, and histology. Subsequently, the TOWARDS score (range 0-53) was developed from these variables. Internal validation showed an optimism-corrected C-index of 0.723 and a calibration slope of 0.834. The decision curve analysis showed the superiority of this score over the University of California, Los Angeles (UCLA) Integrated Staging System and GRade, Age, Nodes, and Tumor score. CONCLUSIONS: The authors' novel TOWARDS scoring model had good accuracy for predicting disease recurrence in patients with hrRCC, and the clinical practicability was superior to that of the existing models.

Real-world outcomes of nivolumab plus ipilimumab combination therapy for advanced renal cell carcinoma in Japanese patients: data with a minimum of 3 years of follow-up.

BACKGROUND: Long-term follow-up data regarding treatment outcomes of nivolumab plus ipilimumab combination therapy for advanced renal cell carcinoma as a first-line therapy are limited in real-world Japanese populations. METHODS: We retrospectively evaluated data of 56 advanced renal cell carcinoma patients treated with nivolumab plus ipilimumab, with a follow-up of at least 3 years. Survival, tumour response and adverse event profiles were assessed. RESULTS: A total of 41 patients (73%) were histopathologically diagnosed with clear-cell renal cell carcinoma, and 34 (61%) were categorized into the International Metastatic renal cell carcinoma Database Consortium intermediate-risk group. The median follow-up period was 34.4 months. Regarding an effectiveness profile, median progression-free survival, time to treatment failure and overall survival were 9.01, 12.5 and 49.0 months, respectively. Objective response was observed in 27 patients (48%), including eight patients with complete response (14%), and the median duration of response was 30.8 months. Multivariate analyses showed that clear-cell histology was an independent factor of longer overall survival (hazard ratio: 0.23, P = 0.0013). Regarding safety profiles, adverse events of any grade and those with grade ≥3 developed in 40 (71%) and 25 patients (45%), respectively. Median time to adverse event development was 1.68 months. Treatment was interrupted in 28 patients (50%), and corticosteroid administration was needed in 25 (45%). CONCLUSION: The 3-year follow-up data showed that nivolumab plus ipilimumab combination therapy exhibited a feasible effectiveness in real-world Japanese patients with advanced renal cell carcinoma. Accordingly, the high risk of adverse event development, which often requires treatment withdrawal and corticosteroid administration, should be considered.

Predictive factors and oncological outcomes of pathological T3a upstaging in patients with clinical T1 renal cell carcinoma undergoing partial nephrectomy.

OBJECTIVES: To investigate predictive factors and oncological outcomes of pathological T3a upstaging in renal cell carcinoma patients who were initially diagnosed as clinical T1 and treated with partial nephrectomy. METHODS AND MATERIALS: The clinical records and survival data of 1617 patients, who had undergone partial nephrectomy for clinical T1 renal cell carcinoma at Tokyo Women's Medical University, Tokyo, Japan between January 2011 and December 2020, were analyzed retrospectively. RESULTS: Of 1617 clinical T1 renal cell carcinoma patients who underwent partial nephrectomy, 28 (1.73%) had pathological T3a upstaging. In the multivariable analysis for pathological T3a upstaging using logistic regression models, male sex and clinical T1b were significant factors associated with pathological T3a upstaging (male sex: odds ratio = 5.07, 95% confidence interval: 1.18-21.8, clinical T1b: odds ratio = 8.36, 95% confidence interval: 3.56-19.6). The Kaplan-Meier method of the recurrence-free survival showed shorter recurrence-free survival in patients with pathological T3a upstaging than in those with pathological T1 (P < 0.0001). In the multivariable analysis using Cox proportional hazards regression models, pathological T3a upstaging was no longer significantly associated with recurrence-free survival after adjustment for other pathological factors (hazard ratio = 1.59, 95% confidence interval: 0.58-4.36). In a sensitivity analysis that analyzed its components individually instead of whole pathological T3a, neither perinephric fat invasion, sinus fat invasion, nor renal vein invasion was associated with recurrence-free survival. CONCLUSIONS: Male sex and clinical T1b were significant predictors for pathological T3a upstaging after partial nephrectomy in clinical T1 renal cell carcinoma patients. Although patients with pathological T3a upstaging had worse recurrence-free survival compared with those without upstaging, multivariable analyses revealed that pathological T3a upstaging was not an independent predictor for poor recurrence-free survival.