Objectives We evaluated whether the treatment history of low‐dose rituximab affected safety profiles, and humoral and cellular responses induced by severe acute respiratory syndrome coronavirus 2 messenger ribonucleic acid vaccine in healthy controls and kidney transplant recipients. Methods We enrolled 10 healthcare workers as controls, 22 kidney transplant recipients with rituximab, and 36 kidney transplant recipients without rituximab without history of coronavirus disease 2019 who received two doses of vaccine. We assessed anti‐severe acute respiratory syndrome coronavirus 2 spike antibody and the antigen‐specific T cells using enzyme‐linked immunospot against spike protein at baseline and after two doses of vaccine. Results All controls showed anti‐severe acute respiratory syndrome coronavirus 2 antibody seroconversion and enzyme‐linked immunospot positivity. Only 19/58 (33%) kidney transplant recipients experienced anti‐severe acute respiratory syndrome coronavirus 2 antibody seroconversion and 31/58 (53%) kidney transplant recipients developed enzyme‐linked immunospot assay positivity after vaccination. The anti‐severe acute respiratory syndrome coronavirus 2 antibody seroconversion rate and enzyme‐linked immunospot assay positivity rate after vaccination were not significantly different between kidney transplant recipients with or without rituximab. Multivariate regression analysis demonstrated rituximab was not associated with a lack of humoral and cellular responses to the vaccine. Conclusions Low‐dose rituximab in kidney transplant recipients did not affect humoral or cellular responses to the severe acute respiratory syndrome coronavirus 2 messenger ribonucleic acid vaccine without severe systemic adverse events including the deterioration of kidney function.

Data on the outcomes of third- or fourth-line therapy for metastatic renal cell carcinoma (mRCC) are limited. The aim of our study was to evaluate the efficacy of therapy beyond the second line. We retrospectively analysed data of mRCC patients who underwent systemic therapy at Yamagata University Hospital. The best objective response (BOR), response rate (RR), and progression-free survival (PFS) were assessed for each line of treatment. To investigate the correlation between overall survival (OS) and the number of treatment lines during a patient’s lifetime, the median OS was assessed using univariate and multivariate analyses. In the first-, second-, and third-line therapies, approximately 20% of patients had long PFS of >15 months. In targeted treatments beyond the third line, only one treatment suppressed disease progression for >10 months. Among patients who died during the follow-up period, those treated with triple and quadruple lines had similar OS (42.5 months vs. 48.4 months, respectively). Multivariate analysis showed that patients with triple or more lines of therapy had better OS; however, quadruple or more lines of therapy was not an independent prognostic factor. We concluded that third-line systemic therapy could improve OS; however, fourth-line therapy could not.

We evaluated the humoral and cellular immune responses and safety of the third severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA vaccine with a longer interval after the second vaccination in kidney transplant recipients (KTRs). We enrolled 54 kidney transplant recipients without a history of coronavirus disease 2019 (COVID-19), who received a third dose of the vaccine. We assessed anti-SARS-CoV-2 spike antibody and antigen-specific T cells using enzyme-linked immunospot (ELISpot) against the spike protein at baseline, after the second vaccination, and after the third vaccination. We also evaluated the adverse events related to each dose of the vaccine. The duration between the second and third vaccinations was 7 ± 1 month. All 17 (100%) KTRs with anti-SARS-CoV-2 antibody positivity after the second vaccination and 27 of 37 (73%) KTRs without anti-SARS-CoV-2 antibody positivity after the second vaccination were positive for anti-SARS-CoV-2 antibodies (p=0.022). Anti-SARS-CoV-2 antibody titers were significantly higher than those after the second vaccination (p<0.001). Age ≥ 60 years and lymphocyte count < 1150/mm3 were confirmed as risk factors for anti-SARS-CoV-2 antibody negativity after the third vaccination in multivariate regression analysis. ELISpot cytokine activities were positive after the third vaccination in 26 of 29 (90%) KTRs with ELISpot cytokine activity positivity after the second vaccination and 12 of 24 (50%) KTRs without ELISpot cytokine activity after the second vaccination. The rate of change in cytokine activity after the third vaccination was significantly higher than that after the second vaccination (p<0.001). Only lymphocyte counts less than 1150/mm3 were confirmed as risk factors for ELISpot cytokine activity negativity in the multivariate regression analysis. Systemic adverse events classified as greater than moderate did not differ for each vaccine dose. None of the patients showed clinical symptoms of acute rejection. The third SARS-CoV-2 mRNA vaccine administration, with a longer interval after the second vaccination, improved humoral and cellular immune responses to SARS-CoV-2 mRNA vaccines without severe adverse effects in the KTRs.

Abbreviations & Acronyms CI = confidence interval CNS = central nervous system CRP = C-reactive protein ECOG PS = Eastern Cooperative Oncology Group Performance Status HR = hazard ratio IMDC = International Metastatic Renal Cell Carcinoma Database Consortium LDH = lactate dehydrogenase LNL = lower normal limit mRCC = metastatic renal cell carcinoma MSKCC = Memorial Sloan Kettering Cancer Center NA = not available NLR = neutrophil-tolymphocyte ratio OS = overall survival RCC = renal cell carcinoma TKI = tyrosine kinase inhibitor UNL = upper normal limit Objectives: To create a new model for the prediction of overall survival in synchronous metastatic renal cell carcinoma. Methods: Medical records of 158 patients with metastatic renal cell carcinoma diagnosed at the Yamagata University Hospital from August 2007 to February 2018 were reviewed. Among them, 77 with synchronous metastatic renal cell carcinoma were retrospectively analyzed using the univariate and multivariate analyses. A new prognostic model was constructed, followed by a bootstrap validation to estimate the model fitting. In addition, these prognostic factors were estimated in 67 metachronous metastatic renal cell carcinoma patients. Results: Five independent prognostic factors were identified in synchronous metastatic renal cell carcinoma: cT3/4, cN1, high corrected calcium, >3.6 neutrophil-to-lymphocyte ratio and central nerve system metastasis. The number (%) and overall survival (95% confidence interval) in the favorable-(0 or 1 risk factor), intermediate-(2 risk factors) and poor-risk (≥3 risk factors) groups were 29 (45.3%) and 67.4 (31.8-NA), 21 (32.8%) and 16.8 (10.0-27.6), and 14 (21.9%) and 9.1 (7.3-13.7) months, respectively. The C-index was 0.72. Patients in the favorable-risk group had better overall survival with nephrectomy than without nephrectomy (hazard ratio 0.29, 95% confidence interval 0.09-0.91 with nephrectomy). In metachronous metastatic renal cell carcinoma, these prognostic factors showed no statistical differences in the overall survival. Conclusions: Prognostic factors are completely different between synchronous and metachronous metastatic renal cell carcinoma. The new model for synchronous metastatic renal cell carcinoma can predict a good candidate for cytoreductive nephrectomy.

Eukaryotic translation initiation factor 4E-binding protein 1 (4EBP1) is phosphorylated and activated by mammalian target of rapamycin complex 1, which serves as a regulator of cell growth, cell survival, metastasis and angiogenesis in many types of cancer. The aim of this study was to evaluate the role of phosphorylated 4EBP1 (p4EBP1) in primary renal cell carcinoma (RCC) as a biomarker in metastatic RCC (mRCC) and non-mRCC cohorts. Primary tumor tissue from 254 non-mRCC and 60 mRCC patients were immunohistochemically stained for t4EBP1 and p4EBP1. The disease-free interval (DFI) categorized by the expressions and clinical parameters were assessed by univariate and multivariate analysis in the non-mRCC cohort. Then, the cause-specific survival (CSS) was assessed in the mRCC cohort by the same methods as used in the non-mRCC cohort. In the non-mRCC cohort, patients with t4EBP1 expression had no RCC recurrence. Patients with p4EBP1 expression had the shorter DFI in univariate analysis (P=0.037). p4EBP1 and pT1b-4 expression levels were independent predictors for de novo metastasis. In the mRCC cohort, intermediate/poor MSKCC risk, non-clear cell RCC, and no p4EBP1 expression were correlated with poor CSS on multivariate analysis. Expression of p4EBP1 could be a predictive biomarker for de novo metastasis in non-mRCC patient cohort. By contrast, mRCC patients showing no p4EBP1 expression had shorter CSS than patients with p4EBP1 expression.