Long-term outcomes of the first prospective study of active surveillance for prostate cancer in Japan.

BACKGROUND: Active surveillance for prostate cancer was initiated in the early 2000s. We assessed the long-term outcomes of active surveillance in Japan. METHODS: This multicenter prospective observational cohort study enrolled men aged 50-80 years with stage cT1cN0M0 prostate cancer in 2002 and 2003. The eligibility criteria included serum prostate-specific antigen level ≤ 20 ng/mL, ≤ 2 positive cores per 6-12 biopsy samples, Gleason score ≤ 6, and cancer involvement < 50% in the positive core. Patients were encouraged to undergo active surveillance. Prostate-specific antigen levels were measured bimonthly for 6 months and every 3 months thereafter. Triggers for recommending treatment were prostate-specific antigen doubling time of < 2 years and pathological progression on repeat biopsy. RESULTS: Among 134 patients, 118 underwent active surveillance. The median age, prostate-specific antigen level at diagnosis, and maximum cancer occupancy were 70 years, 6.5 ng/mL, and 11.2%, respectively. Ninety-one patients had only one positive cancer core. The median observation period was 10.7 years. At 1 year, 65.7% underwent a repeat biopsy, and 37% of patients experienced pathological progression. The active surveillance continuation rates at 5, 10, and 15 years were 28%, 9%, and 4%, respectively. One prostate cancer-related death occurred in a patient who refused treatment despite pathological progression at the one-year repeat biopsy. CONCLUSION: Active surveillance according to this study protocol was associated with conversion to the next treatment without delay, when indicated, despite the selection criteria and follow-up protocols being less rigorous than those recommended in current international guidelines.

Japanese clinical practice guidelines for prostate cancer 2023.

This fourth edition of the Japanese Clinical Practice Guidelines for Prostate Cancer 2023 is compiled. It was revised under the leadership of the Japanese Urological Association, with members selected from multiple academic societies and related organizations (Japan Radiological Society, Japanese Society for Radiation Oncology, the Department of EBM and guidelines, Japan Council for Quality Health Care (Minds), Japanese Society of Pathology, and the patient group (NPO Prostate Cancer Patients Association)), in accordance with the Minds Manual for Guideline Development (2020 ver. 3.0). The most important feature of this revision is the adoption of systematic reviews (SRs) in determining recommendations for 14 clinical questions (CQs). Qualitative SRs for these questions were conducted, and the final recommendations were made based on the results through the votes of 24 members of the guideline development group. Five algorithms based on these results were also created. Contents not covered by the SRs, which are considered textbook material, have been described in the general statement. In the general statement, a literature search for 14 areas was conducted; then, based on the general statement and CQs of the Japanese Clinical Practice Guidelines for Prostate Cancer 2016, the findings revealed after the 2016 guidelines were mainly described. This article provides an overview of these guidelines.

Arterio-ureteral fistula from a pseudoaneurysm of the right common iliac artery after robot-assisted laparoscopic radical cystectomy: A case report.

Arterio-ureteral fistulas (AUFs), which are relatively rare but potentially life-threatening, require prompt diagnosis and treatment. We reported a case of AUFs following robot-assisted laparoscopic radical cystectomy (RARC) with extended pelvic lymph node dissection and ileal conduit urinary diversion for muscle-invasive bladder cancer, which resulted in massive hemorrhage. Urine leaked from the anastomosis between the ureter, and the end of the ileal conduit was infected, which resulted in an AUF between the pseudoaneurysm of the right common iliac artery and the ureter. The AUF was managed successfully by vascular intervention with an arterial stent graft.

Effect of HLA Genotype on Anti-PD-1 Antibody Treatment for Advanced Renal Cell Carcinoma in the SNiP-RCC Study.

Immune checkpoint blockade therapies are widely used for cancer treatment, including advanced renal cell carcinoma (RCC). This study aimed to investigate the impact of zygosity in HLA genes and individual HLA genotypes on the efficacy of an anti-PD-1 Ab, nivolumab, in treating advanced RCC. Patient enrollment was conducted across 23 institutions in Japan from August 19, 2019, to September 30, 2020, with follow-up concluding on March 31, 2021. HLA genotype imputation of HLA-A, B, and C, DQB1, and DRB1 loci was performed. Among 222 patients, the presence of at least one homozygosity of the HLA-II allele significantly improved the best objective response (hazard ratio, 0.34; 95% confidence interval, 0.21-0.96; p = 0.042). The HLA evolutionary divergence (HED) of the HLA-A and HLA-B loci was higher than the HLA-C (p < 0.0001 and p < 0.0001, respectively), with high HED of the HLA-B locus correlating to clinical benefits in nivolumab treatment (hazard ratio, 0.44; 95% confidence interval, 0.21-0.90; p = 0.024) and improving cancer-specific survival compared with the low group (p = 0.0202). Additionally, high HED of the HLA-B locus was correlated with the number of infiltrated CD8+ cells in the tumor microenvironment (correlation coefficient, 0.4042). These findings indicate that the diversity of the HLA-B locus plays a significant role in the anti-tumor effect of nivolumab treatment in advanced RCC, potentially offering insights for improved risk stratification in nivolumab treatment and leading to better medical management of advanced RCC.

The lymphocyte-to-monocyte ratio as a significant inflammatory marker associated with survival of patients with metastatic renal cell carcinoma treated using nivolumab plus ipilimumab therapy.

BACKGROUND: Nivolumab plus ipilimumab (NIVO + IPI) is the first-line treatment for patients with metastatic renal cell carcinoma (mRCC). While approximately 40% of patients treated with NIVO + IPI achieve a durable response, 20% develop primary resistance with severe consequences. Therefore, there is a clinical need for criteria to select patients suitable for NIVO + IPI therapy to optimize its therapeutic efficacy. Accordingly, our aim was to evaluate the association between candidate biomarkers measured before treatment initiation and survival. METHODS: This was a multi-institutional, retrospective, cohort study of 183 patients with mRCC treated with systematic therapies between August 2015 and July 2023. Of these, 112 received NIVO + IPI as first-line therapy: mean age, 68 years; men, 83.0% (n = 93), and clear cell histology, 80.4% (n = 90). Univariable and multivariable analyses were used to evaluate associations between biomarkers and survival. RESULTS: On univariate analysis, high C-reactive protein and systemic index, a high neutrophil-to-lymphocyte and platelet-to-lymphocyte ratio, and a low lymphocyte-to-monocyte ratio (LMR) were associated with shorter overall survival (OS). On multivariable analysis, a LMR ≤ 3 was retained as an independent factor associated to shorter OS with the highest accuracy (C-index, 0.656; hazard ratio, 7.042; 95% confidence interval, 2.0-25.0; p = 0.002). CONCLUSION: A low LMR may identify patients who would be candidate for NIVO + IPI therapy for mRCC.

Predictive factors of renal function after robot-assisted partial nephrectomy in clinical T1b tumors.

Robot-assisted partial nephrectomy (RAPN) has been shown to be a safe and effective method for treatment of small renal tumors, including clinical T1b renal cell carcinoma (RCC); however, the impact of RAPN for cT1b renal tumors on renal function is not well understood. In this retrospective study, 50 patients who underwent RAPN for cT1b renal tumors were evaluated for pre- and post-operative renal function and perioperative clinical factors. Renal function was assessed using the estimated glomerular filtration rate (eGFR) at baseline and on postoperative days (POD) 1, 7, 30, and 180.A significant renal functional decline was defined as ≥ 15% reduction in eGFR at POD180 compared with eGFR at baseline. Logistic regression analyses were used to identify risk factors for renal function decline, including age, sex, RENAL nephrometry score, operative time, and estimated blood loss. The median patient age was 62 years, and the median tumor diameter and RENAL nephrometry score were 44 mm (IQR 43-50) and 8 (IQR 7-9), respectively. Of these patients, 16 (36%) showed a significant renal functional decline at POD 180. In the multivariate analysis, the L component of the RENAL nephrometry score and an estimated blood loss of 200 mL or more were identified as significant risk factors for renal functional decline. These findings suggest that the preoperatively definable L component of the RENAL nephrometry score and intraoperative blood loss, which may be modifiable factors, play significant roles in post-RAPN renal function decline.

Influence of genetic polymorphisms in vascular endothelial-related genes on the clinical outcome of axitinib in patients with metastatic renal cell carcinoma.

OBJECTIVE: Axitinib is an oral multi-target tyrosine kinase inhibitor used for the treatment of renal cell carcinoma (RCC). Because of the severe adverse events (AEs) associated with axitinib, patients often need dose reductions or discontinue its use, highlighting the need for effective biomarkers to assess efficacy and/or AEs. The aim of this study was to investigate the relationship between single nucleotide polymorphisms (SNPs) in genes involved in the pharmacodynamic action of axitinib and clinical prognosis and AEs in metastatic RCC (mRCC) patients. METHODS: This study included 80 mRCC patients treated with first-, second-, or third-line axitinib (5 mg orally twice daily). Clinical parameters and genetic polymorphisms were examined in 75 cases (53 males and 22 females). We assessed three SNPs in each of three candidate genes namely, angiotensin-converting enzyme (ACE), nitric oxide synthase 3 (NOS3), and angiotensin II receptor type 1 (AT1R), all of which are involved in axitinib effects on vascular endothelial function. RESULTS: Axitinib-treated patients carrying the ACE deletion allele suffered more frequently from hand-foot syndrome and a deterioration in kidney function (p = .045 and p = 0.005, respectively) whereas those carrying the NOS3 G allele suffered more frequently from proteinuria and multiple AEs (p = .025 and p = 0.036, respectively). CONCLUSIONS: Our study found that the ACE deletion allele and the NOS3 G allele are associated with increased AEs.

Incidence of postoperative cytomegalovirus and BK-polyoma virus infections and graft loss in ABO-incompatible renal transplant recipients: a multicenter retrospective study.

OBJECTIVES: The current study aimed to examine the incidence of perioperative infections and graft viability in ABO-compatible and ABO-incompatible renal transplant recipients. METHODS: We included 643 living donor renal transplant recipients registered in the Michinoku Renal Transplant Network from 1998 to 2021. Patients were divided into the ABO-compatible and ABO-incompatible kidney transplantation groups. We compared the characteristics of the two groups and evaluated the incidence of postoperative viral infections (cytomegalovirus and BK virus), graft loss-free survival, and overall survival between the two groups. RESULTS: Of 643 patients, 485 (75%) and 158 (25%) were ABO-compatible and ABO-incompatible renal transplant recipients, respectively. Postoperative viral infections, rituximab use, and plasma exchange were significantly more common in ABO-incompatible than in ABO-compatible transplant recipients. However, there were no significant differences in terms of other background characteristics. The ABO-incompatible group was more likely to develop viral infections than the ABO-compatible group. Graft loss-free survival and overall survival did not significantly differ between the two groups. According to the multivariate Cox regression analysis, ABO compatibility was not significantly associated with graft loss-free survival and overall survival. CONCLUSION: Although the incidence of postoperative viral infections in ABO-incompatible renal transplant recipients increased, there was no significant difference in terms of rejection events, graft loss-free survival, and overall survival.

Comparison of perioperative outcomes and complications between intracorporeal, extracorporeal, and hybrid ileal conduit urinary diversion during robot-assisted radical cystectomy: a comparative propensity score-matched analysis from nationwide multi-institutional study in Japan.

BACKGROUND: To investigate the impact of different urinary diversion (UD) techniques on the peri- and postoperative complications of robot-assisted radical cystectomy (RARC) with ileal conduit. METHODS: We retrospectively analyzed 373 patients undergoing RARC with ileal conduit at 11 institutions in Japan between April 2018 and December 2021. Propensity score weighting was performed to adjust for confounding factors such as age, sex, body mass index, performance status, American Society of Anesthesiologists score, previous abdominal surgery, neoadjuvant chemotherapy, and preoperative high T stage (≥ cT3) and high N stage (≥ cN1). Perioperative complications were then compared among three groups: extracorporeal, intracorporeal, and hybrid urinary diversion (ECUD, ICUD, and HUD, respectively). RESULTS: A total of 150, 68, and 155 patients received ECUD, HUD, and ICUD, respectively. Bowel reconstruction time and UD time were significantly shorter in the ECUD group (p < 0.001), and console time was significantly longer and blood loss was significantly higher in the ICUD group (p < 0.001). For postoperative complications (Clavien-Dindo Classification grade ≥ 3), surgical site infection (p = 0.004), pelvic abscess (p = 0.013), anastomotic urine leak (p = 0.007), and pelvic organ prolapse (p = 0.011) significantly occurred in the ECUD group. For all grades, ileus was more common in the HUD group, whereas anastomotic stricture was more common in the ECUD group compared with the other groups (p < 0.05). CONCLUSIONS: Severe complications did not increase after HUD and ICUD compared with ECUD; however, console time tended to be longer and blood loss was slightly higher during RARC.

Impact of timing of rejection episode on cardiovascular events in living donor kidney transplantation: a multicenter retrospective study.

BACKGROUND: Cardiovascular diseases are still highly prevalent after kidney transplantation. However, little is known about the impact of the timing of rejection episodes on cardiovascular disease. The study aimed to analyze the influence of the timing of rejection episodes on cardiovascular events in recipients of living donor kidney transplantation. METHODS: We studied 572 living donor kidney transplant recipients from the Michinoku Renal Transplant Network (MRTN), which includes 6 centers in the Tohoku region of Japan. Fine-Gray proportional hazards regression analysis with time-dependent variables was used to assess the effect of rejection episode on cardiovascular events. Recipients were divided into three groups: those without rejection (non-rejection, 370 patients), rejection within 6 months after transplantation (early rejection, 99 patients), and rejection after 6 months (late rejection, 103 patients). The effect of timing on cardiovascular events was evaluated using Fine-Gray proportional hazards regression analysis. RESULTS: During a median follow-up of 77 months, 70 patients experienced cardiovascular events. Rejection episodes were significantly associated with cardiovascular events (hazard ratio [HR]: 2.08, 95% confidence interval [CI]: 1.26-3.43, P = 0.004), along with age and dialysis vintage. The 5-year cumulative incidence of cardiovascular events was significantly higher in the late rejection group than in the early rejection group (15% vs. 3.3%, P = 0.021). However, no significant difference in 5-year cumulative cardiovascular event incidence was observed between the early rejection and non-rejection groups. Late rejection was significantly associated with cardiovascular events (HR: 2.40, 95% CI: 1.38-4.18, P = 0.002), whereas early rejection was not significantly correlated with cardiovascular event risk (HR: 1.18, P = 0.670). CONCLUSIONS: Rejections occurring more than 6 months after transplantation is significantly associated with risk of cardiovascular events. TRIAL REGISTRATION NUMBER: 2019-099-1, date of registration; 3 Dec. 2019, retrospectively registered.

BRCA2 Frameshift Mutation in de novo Small-Cell Neuroendocrine Carcinoma of the Prostate: A Case Report.

A 66-year-old male was diagnosed with cT4N0M1b small-cell neuroendocrine carcinoma of the prostate. Four months after the administration of combined androgen blockade, multiple novel metastatic regions in the lung and liver and progression of bone metastasis were observed. The patient was referred to our hospital because of biochemical and radiographic progression after four cycles of docetaxel as a first-line therapy for castration-resistant prostate cancer. Transurethral resection of the prostate and hepatic biopsy revealed small-cell carcinoma with positive expression of neuroendocrine markers. The FoundationOne CDx next-generation sequencing test revealed several pathogenic variants, including BRCA2 (W1692fs*3), KEAP1 (R320W), and TP53 (C2385) mutation. After four cycles of chemotherapy with carboplatin plus etoposide (CE), the metastatic regions regressed markedly. The prostate-specific antigen (PSA) and neuron-specific enolase (NSE) level decreased by 96.9% and 91.6%, respectively. However, 2 months after the completion of four cycles of CE, elevation of tumor marker levels, and re-growth of the metastatic regions were observed. Although olaparib, a poly (ADP-ribose) polymerase inhibitor (PARPi), achieved a 45.2% decrease in NSE, the patient rejected to continue therapy because of G2 adverse events. After receiving an additional two cycles of CE and one cycle of cabazitaxel, the patient died because of cancer progression 24 months after the initial treatment for prostate cancer. Here, we present a case of BRCA2-altered small-cell neuroendocrine prostate cancer treated with both platinum-containing chemotherapy and PARPi. Both therapies achieved an initial response; however, durable responses were not obtained. Additional discussion regarding the optimal treatment strategy for BRCA-altered small-cell/neuroendocrine prostate cancer is required.

The efficacy of molecular targeted therapy and nivolumab therapy for metastatic non-clear cell renal cell carcinoma: A retrospective analysis using the Michinoku Japan urological cancer study group database.

OBJECTIVES: To investigate the efficacy of pharmacotherapy for metastatic non-clear cell renal cell carcinoma (nccRCC) in Japanese population. METHODS: In this retrospective analysis, we compared the time to treatment failure (TTF) for molecular-targeted agents as first-line therapy, or nivolumab therapy as sequential therapy between ccRCC and nccRCC using the data of Japanese metastatic RCC patients registered in the Michinoku Japan Urological Cancer Study Group database. RESULTS: In total, 511 cases of ccRCC and 77 cases of nccRCC were treated with pharmacotherapy. After excluding the patients who received cytokine therapy, chemotherapy, or others, there were 391 ccRCC patients and 60 nccRCC patients who were treated with tyrosine kinase inhibitors (TKIs), and 7 ccRCC patients and 7 nccRCC patients who were treated with mammalian-target of rapamycin inhibitors (mTORIs). In addition, 132 ccRCC patients and 16 nccRCC patients received nivolumab. There was no significant difference in IMDC risk classification before first-line therapy between ccRCC and nccRCC groups, or in each subgroup within the nccRCC group. TTF for TKIs (161 days, 95% CI: 75-212 days) and mTORIs (21 days, 95% CI: 9-31 days) didn't differ significantly between nccRCC and ccRCC groups (205 days, 95% CI: 174-243 days and 33 days, 95% CI: 8-113 days, respectively). TTF for TKIs was significantly longer than that for mTORIs in nccRCC group (p<0.01). There was no significant difference in TTF between the different TKIs in nccRCC group. In addition, no significant difference in TTF for nivolumab was seen between ccRCC and nccRCC groups. CONCLUSIONS: The results showed that the efficacy of molecular-targeted agents as first-line therapy was similar oncological outcomes between metastatic nccRCC and ccRCC in Japanese patients. TKIs may be more effective than mTORIs in metastatic nccRCC patients. Nivolumab administration might also be as effective in nccRCC patients as in ccRCC patients in Japanese population.

Androgen deprivation therapy caused a drastic proliferation of B-cell lymphoma with IgG4-related disease in patients with prostate cancer: a case report.

BACKGROUND: We report a case of diffuse large B-cell lymphoma that progressed rapidly after androgen deprivation therapy for prostate cancer in a patient with a history of IgG4-related disease. Estrogen has been reported to be a possible cause of acute exacerbations of malignant lymphoma only in mouse models. Therefore, its clinical significance has not been clarified. CASE PRESENTATION: This case report describes a 75-year-old man with prostate cancer who had IgG4-related disease. Hormone therapy was initiated to treat prostate cancer, but he developed dyspnea and back pain. A diagnosis was made of diffuse large B-cell lymphoma. Immunohistochemistry was positive for estrogen receptor ß, which led us to suspect rapid progression of diffuse large B-cell lymphoma due to estrogen suppression by gonadotropin-releasing hormone antagonists. Hormone therapy was discontinued, and the patient received R-CHOP therapy. Subsequently, the lymphoma masses shrunk, and the patient obtained remission. CONCLUSION: This case is the first report of clinical significance regarding the crucial role of estrogen and estrogen receptor ß in malignant lymphoma in a patient with IgG4-related disease. Our report aims to raise awareness of the need to carefully select treatment options for prostate cancer patients with IgG4-related disease or lymphoma.

Preoperative prognostic model for localized and locally advanced renal cell carcinoma: Michinoku Japan Urological Cancer Study Group.

BACKGROUND: The Modified International Metastatic Renal Cell Carcinoma Dataset Consortium model (mIMDC) is a preoperative prognostic model for pT3cN0M0 renal cell carcinoma (RCC). This study aimed to validate the mIMDC and to construct a new model in a localized and locally advanced RCC (LLRCC). METHODS: A database was established (the Michinoku Japan Urological Cancer Study Group database) consisting of 79 patients who were clinically diagnosed with LLRCC (cT3b/c/4NanyM0) and underwent radical nephrectomy from December 2007 to May 2018. Using univariable and multivariable analyses, we retrospectively analyzed disease-free survival (DFS) and overall survival (OS) in this database, constructed a new prognostic model according to these results, and estimated the model fit using c-index on the new and mIMDC models. RESULTS: Independent poorer prognostic factors for both DFS and OS include the following: ≥ 1 Eastern Cooperative Oncology Group performance status, 2.0 mg/dL C-reactive protein, and > upper normal limit of white blood cell count. The median DFS in the favorable (no factor), intermediate (one factor), and poor-risk group (two or three factors) was 76.1, 14.3, and 4.0 months, respectively (P < 0.001). The 3-year OS in the favorable, intermediate, and poor-risk group were 92%, 44%, and 0%, respectively (P < 0.001). The c-indices of the new and mIMDC models were 0.67 and 0.60 for DFS (P = 0.060) and 0.74 and 0.63 for OS (P = 0.012), respectively. CONCLUSION: The new preoperative prognostic model in LLRCC can be used in patient care and clinical trials.

The Current Trend of Radiation Therapy for Patients with Localized Prostate Cancer.

A recent approach to radiotherapy for prostate cancer is the administration of high doses of radiation to the prostate while minimizing the risk of side effects. Thus, image-guided radiotherapy utilizes advanced imaging techniques and is a feasible strategy for increasing the radiation dose. New radioactive particles are another approach to achieving high doses and safe procedures. Prostate brachytherapy is currently considered as a combination therapy. Spacers are useful to protect adjacent organs, specifically the rectum, from excessive radiation exposure.

Immunological risk and complement genetic evaluations in early onset de novo thrombotic microangiopathy after living donor kidney transplantation: A Japanese multicenter registry.

BACKGROUND: Thrombotic microangiopathy (TMA) after kidney transplantation (KTx), particularly early onset de novo (dn) TMA, requires immediate interventions to prevent irreversible organ damage. This multicenter study was performed to investigate the allogeneic clinical factors and complement genetic background of dnTMA after KTx. METHODS: Perioperative dnTMA after KTx within 1 week after KTx were diagnosed based on pathological or/and hematological criteria at each center, and their immunological backgrounds were researched. Twelve aHUS-related gene variants were examined in dnTMA cases. RESULTS: Seventeen recipients (15 donors) were enrolled, and all dnTMA cases were onset within 72-h of KTx, and 16 of 17 cases were ABO incompatible. The implementation rate of pre-transplant plasmaphereses therapies were low, including cases with high titers of anti-A/anti-B antibodies. Examination of aHUS-related gene variants revealed some deletions and variants with minor allele frequency (MAF) in Japan or East Asian genome databases in genes encoding alternative pathways and complement regulatory factors. These variants was positive in 8 cases, 6 of which were positive in both recipient and donor, but only in one graft loss case. CONCLUSIONS: Although some immunological risks were found for dnTMA after KTx, only a few cases developed into TMA. The characteristic variations revealed in the present study may be novel candidates related to dnTMA in Japanese or Asian patients, but not pathogenic variants of aHUS. Future studies on genetic and antigenic factors are needed to identify factors contributing to dnTMA after KTx.

Real clinical outcomes of nivolumab plus ipilimumab for renal cell carcinoma in patients over 75 years old.

BACKGROUND: Although nivolumab plus ipilimumab is the standard treatment for metastatic renal cell carcinoma (RCC), its efficacy and safety in older patients remain unclear. Therefore, this study aimed to assess the clinical outcomes of nivolumab plus ipilimumab for metastatic RCC in patients aged ≥ 75 years. METHODS: We enrolled 120 patients with metastatic RCC treated with nivolumab plus ipilimumab from August 2015 to January 2023. Objective response rates (ORRs) were compared between patients aged < 75 and ≥ 75 years. Progression-free survival (PFS), overall survival (OS), and adverse events were compared between the groups. Adverse events were evaluated according to the Response Evaluation Criteria in Solid Tumors 1.1. RESULTS: Among the patients, 57 and 63 were classified as intermediate and poor risk, respectively, and one could not be classified. The median follow-up duration after the initiation of treatment was 16 months. The patient characteristics between the groups, except for age, were not significantly different. Intergroup differences in ORR (42% vs. 40%; p = 0.818), PFS (HR: 0.820, 95% CI 0.455-1.479; p = 0.510), and median OS (HR: 1.492, 95% CI 0.737-3.020; p = 0.267) were not significant. The incidence of adverse events (50% vs. 67%; p = 0.111) and nivolumab plus ipilimumab discontinuation due to adverse events was not significantly different between the groups (14% vs. 13%; p = 0.877). CONCLUSIONS: The effectiveness of nivolumab plus ipilimumab was comparable between patients with metastatic RCC aged < 75 and those ≥ 75 years with respect to their ORRs, PFS, OS, and adverse event rates.

Primary resistance to nivolumab plus ipilimumab therapy in patients with metastatic renal cell carcinoma.

BACKGROUND: Nivolumab plus ipilimumab (NIVO+IPI) is the first-line treatment for patients with metastatic renal cell carcinoma (mRCC). Approximately 40% of patients achieve a durable response; however, 20% develop primary resistant disease (PRD) to NIVO+IPI, about which little is known in patients with mRCC. Therefore, this investigation aimed to evaluate the clinical implication of PRD in patients with mRCC to select better candidates in whom NIVO+IPI can be initiated as first-line therapy. METHODS: This multi-institutional retrospective cohort study used data collected between August 2015 and January 2023. In total, 120 patients with mRCC treated with NIVO+IPI were eligible. Associations between immune-related adverse events and progression-free survival, overall survival (OS), and objective response rate were analyzed. The relationship between other clinical factors and outcomes was also evaluated. RESULTS: The median observation period was 16 months (interquartile range, 5-27). The median age at NIVO+IPI initiation was 68 years in the male-dominant population (n = 86, 71.7%), and most patients had clear cell histology (n = 104, 86.7%). PRD was recorded in 26 (23.4%) of 111 investigated patients during NIVO+IPI therapy. Patients who experienced PRD showed worse OS (hazard ratio: 4.525, 95% confidence interval [CI]: 2.315-8.850, p < 0.001). Multivariable analysis showed that lymph node metastasis (LNM) (odds ratio: 4.274, 95% CI: 1.075-16.949, p = 0.039) was an independent risk factor for PRD. CONCLUSIONS: PRD was strongly correlated with worse survival rates. LNM was independently associated with PRD in patients with mRCC receiving NIVO+IPI as first-line therapy and might indicate that a candidate will not benefit from NIVO+IPI.