[A Retrospective Study on the Malignancies after Renal Transplantation].

Detection of post-transplant malignant tumors and the analysis of the associated risk factors is important for monitoring the progress after renal transplantation. In this study, we retrospectively examined the medical records of 298 patients who underwent renal transplantation at two facilities in Nagasaki Prefecture (Nagasaki University Hospital and National Hospital Organization Nagasaki Medical Center). Of the 298 patients, 45 (15.1%) patients had developed malignant tumors with 50 lesions. The most common type of malignant tumor was skin cancer (eight patients; 17.8%), followed by renal cancer (six patients; 13.3%), and pancreatic cancer and colorectal cancer, (four patients; 9.0% each). Five patients (11.1%) had multiple cancers, four of whom had skin cancer. The cumulative incidence within 10 and 20 years after renal transplantation was 6.0 and 17.9%, respectively. Univariate analysis identified age at transplantation and administration of cyclosporine and rituximab as risk factors, while multivariate analysis identified age at transplantation and administration of rituximab as independent factors. The administration of rituximab was associated with the development of malignant tumors. However, further investigation is required to establish the association with post-transplant malignant neoplasms.

Intravesical mitomycin C (MMC) and MMC + cytosine arabinoside for non-muscle-invasive bladder cancer: a randomised clinical trial.

OBJECTIVES: To compare the urinary pH, recurrence-free survival (RFS), and safety of adjuvant intravesical therapy in patients with non-muscle-invasive bladder cancer (NMIBC) receiving mitomycin C (MMC) therapy and MMC + cytosine arabinoside (Ara-C) therapy. PATIENTS AND METHODS: A total of 165 patients with NMIBC from six hospitals were randomly allocated to two groups: weekly instillation of MMC + Ara-C (30 mg/30 mL + 200 mg/10 mL) for 6 weeks and the same instillation schedule of MMC (30 mg/40 mL). The primary outcome was RFS, and secondary outcomes were urinary pH and toxicity in the two groups. RESULTS: A total of 81 and 87 patients were randomised into the MMC and MMC + Ara-C groups, respectively. Overall, the RFS in the MMC + Ara-C group was significantly longer (P = 0.018) than that in the MMC group. A similar significant difference was detected in patients with intermediate-risk NMIBC, but not in those with high-risk NMIBC. The mean (SD) urinary pH was significantly higher in the MMC + Ara-C group than in the MMC group, at 6.56 (0.61) vs 5.78 (0.64) (P < 0.001), and the frequency of a urinary pH of >7.0 in the MMC and MMC + Ara-C groups was 6.3% and 26.7%, respectively (P < 0.001). Multivariate analysis models including clinicopathological features and second transurethral resection demonstrated that increased urinary pH was associated with better outcomes (hazard ratio 0.18, 95% confidential interval 0.18-0.038; P < 0.001). In all, there were 14 and 10 adverse events in the MMC and MMC + Ara-C groups, respectively, without a significant difference (P = 0.113). CONCLUSIONS: Our randomised clinical trial suggested that intravesical therapy with MMC and Ara-C is useful and safe for patients with intermediate-risk NMIBC. Increase in urinary pH with Ara-C is speculated as a mechanism for increased anti-cancer effects.

Association between serum calcium levels and prognosis, hematoma volume, and onset of cerebral hemorrhage in patients undergoing hemodialysis.

BACKGROUND: High serum calcium levels should be avoided in patients on hemodialysis (HD) because they can induce cardiovascular diseases and worsen the patient's prognosis. In contrast, low serum calcium levels worsen the prognosis of patients with cerebral hemorrhage in the general population. So far, whether serum calcium levels in patients on HD are associated with cerebral hemorrhage remains unknown. This study aimed to reveal the association between serum calcium and cerebral hemorrhage in patients on HD, including in-hospital death, volume of hematoma, and onset of cerebral hemorrhage. METHODS: This cross-sectional case-control study included 99 patients on HD with cerebral hemorrhage at a single center between July 1, 2007 and December 31, 2017. Controls included 339 patients on HD at a single HD center between July 1, 2011 and June 30, 2012. Data on serum calcium level, patient demographics, and comorbid conditions were collected, and associations between cerebral hemorrhage and subsequent death were evaluated by multivariate logistic regression analysis. Further, the association of these backgrounds and hematoma volume was evaluated by multiple regression analysis. RESULTS: Of the 99 patients, 32 (32%) died from cerebral hemorrhage. The corrected serum calcium level (odds ratio [OR], 2.49; 95% confidence interval [CI], 1.43-4.35; P < 0.001) and antiplatelet drug use (OR, 3.95; 95% CI, 1.50-10.4; P = 0.005) had significant effects on the prognosis. Moreover, the corrected serum calcium (P = 0.003) and antiplatelet drug use (P = 0.01) were significantly correlated with hematoma volume. In the patients, the corrected serum calcium level (OR, 1.54; 95% CI, 1.07-2.22; P = 0.02) was associated with the onset of cerebral hemorrhage, as was pre-hemodialysis systolic blood pressure (per 10 mmHg) (OR, 1.40; 95% CI, 1.23-1.59; P < 0.001). CONCLUSIONS: Although the precise mechanisms remain unknown, a high serum calcium level is associated with cerebral hemorrhage in patients on HD. Thus, we should pay attentions to a patient's calcium level.

Intestinal fatty acid-binding protein levels in patients with chronic renal failure.

BACKGROUND: Intestinal fatty acid-binding protein (I-FABP), a biomarker of enterocyte injury, has been reported to be a diagnostic marker of intestinal ischemia and a prognostic marker in critically ill patients. However, the kinetics of I-FABP in renal failure patients is unknown. We sought to identify I-FABP levels in patients with chronic kidney disease (CKD) and end-stage kidney disease (ESKD) on hemodialysis (HD) and to identify the manner in which the I-FABP levels change. MATERIALS AND METHODS: Adult patients who were admitted for elective cardiac surgery with either normal renal function (NRF), CKD, or ESKD on HD were enrolled. Serum I-FABP levels in NRF and CKD patients and in ESKD patients before and after HD were determined. RESULTS: A total of 124 patients were evaluated: 47 NRF, 53 CKD, and 24 ESKD. The I-FABP levels of the CKD patients and pre-HD ESKD patients were significantly higher than those of the NRF patients (P = 0.018 and P <0.001, respectively). I-FABP levels were significantly negatively correlated with the estimated glomerular filtration rate in NRF and CKD patients (Spearman's ρ = -0.313, P = 0.002). In addition, I-FABP levels in ESKD patients were significantly lower after HD than those before HD (P <0.001). CONCLUSIONS: I-FABP levels in CKD and pre-HD ESKD patients were significantly higher than those in NRF patients. In addition, I-FABP was significantly eliminated by HD in patients with ESKD. Clinicians and researchers should consider this aspect of I-FABP when using it as a diagnostic and prognostic marker in patients with renal insufficiency.

Outcome From a Randomized Controlled Clinical Trial　- Improvement of Peripheral Arterial Disease by Granulocyte Colony-Stimulating Factor-Mobilized Autologous Peripheral-Blood-Mononuclear Cell Transplantation (IMPACT).

BACKGROUND: The clinical usefulness of peripheral blood (PB) mononuclear cell (MNC) transplantation in patients with peripheral arterial disease (PAD), especially in those with mild-to-moderate severity, has not been fully clarified.Methods and Results:A randomized clinical trial was conducted to evaluate the efficacy and safety of granulocyte colony-stimulating factor (G-CSF)-mobilized PBMNC transplantation in patients with PAD (Fontaine stage II-IV and Rutherford category 1-5) caused by arteriosclerosis obliterans or Buerger's disease. The primary endpoint was progression-free survival (PFS). In total, 107 subjects were enrolled. At baseline, Fontaine stage was II/III in 82 patients and IV in 21, and 54 patients were on hemodialysis. A total of 50 patients had intramuscular transplantation of PBMNC combined with standard of care (SOC) (cell therapy group), and 53 received SOC only (control group). PFS tended to be improved in the cell therapy group than in the control group (P=0.07). PFS in Fontaine stage II/III subgroup was significantly better in the cell therapy group than in the control group. Cell therapy-related adverse events were transient and not serious. CONCLUSIONS: In this first randomized, large-scale clinical trial of G-CSF-mobilized PBMNC transplantation, the cell therapy was tolerated by a variety of PAD patients. The PBMNC therapy was significantly effective for inhibiting disease progression in mild-to-moderate PAD.

Final results of a phase II study of S-1 in patients with cytokine-refractory metastatic renal cell carcinoma.

OBJECTIVE: A planned primary analysis of a Phase II study of S-1 demonstrated that the drug was active and tolerable in Japanese patients with cytokine-refractory metastatic renal cell carcinoma. Furthermore, pharmacogenomic analysis suggested that low expression of thymidylate synthase mRNA may have been associated with clinical outcome in terms of overall response rate and progression-free survival. Here, we report the results of the final analysis assessing the efficacy and safety of S-1 including overall survival. METHODS: Patients with renal cell carcinoma were eligible if they had had at least one regimen of cytokine for metastatic disease. S-1 was orally administered on Days 1-28 of a 42-day cycle until disease progression. The primary endpoint was the overall response rate, and the secondary endpoint included progression-free survival, overall survival and safety. RESULTS: A total of 45 patients were treated with S-1 and were fully assessable for efficacy and safety. At the final analysis, a response was seen in 11 patients (overall response rate, 24.4%; 95% confidence interval: 12.9-39.5%), including two patients who achieved a complete response. The final median progression-free and overall survival were 9.2 and 42.8 months, respectively. The safety profile of S-1 was favorable. It was suggested that there was no relation between overall survival and the expression level of thymidylate synthase. CONCLUSION: This final analysis confirms that S-1 treatment is effective and safe in patients with cytokine-refractory renal cell carcinoma.

Impacts of clinicopathologic and operative factors on short-term and long-term survival in renal cell carcinoma with venous tumor thrombus extension: a multi-institutional retrospective study in Japan.

BACKGROUND: Although the percentage of patients with renal cell carcinoma (RCC) extending into venous systems is unexpectedly high, the prognostic impact and independency of venous tumor thrombus-related factors on overall survival (OS) remain controversial. Furthermore, the prognostic impact of various clinicopathologic factors including tumor thrombus-related factors on OS may change with elapsed years after the intervention and also with follow-up duration of participants. The aim of the study is to explore independent and universal predictive preoperative and intraoperative clinicopathologic factors on OS in patients with RCC extending into venous systems using subgroup analysis in terms of restricted follow-up duration and yearly-based survivors. METHODS: Between 1980 and 2009, 292 patients diagnosed with RCC with venous tumor thrombus were retrospectively registered for this study. The prognostic impacts of various clinicopathologic and surgical treatment factors including levels of venous thrombus, venous wall invasion status and likelihood of aggressive cytoreductive operation, were investigated using Kaplan-Meier method and following multivariate Cox proportional hazards model for all patients and those still alive at 1, 2, and 3 years of follow-up. To investigate the impact of follow-up duration on the statistical analyses, multivariate logistic regression analyses were used to explore prognostic factors using restricted data until 1, 2, and 3 years of follow-up. RESULTS: The median follow-up duration was 40.4 months. The 5-year OS was 47.6%. Several independent predictive factors were identified in each subgroup analysis in terms of yearly-based survival and restricted follow-up duration. The presence of tumor thrombus invading to venous wall was independently related to OS in the full-range follow-up data and in survivors at 2 and 3 years of follow-up. Using restricted follow-up data until 1, 2, and 3 years of follow-up, many independent predictive factors changed with follow-up duration, but surgical category could be universal and independent predictive factors. CONCLUSION: The most universal factors affecting improvement both in short-term and long-term survivals could be cytoreductive surgery and absence of venous wall invasion. It may mean that feasible aggressive cytoreductive operation following more reliable preoperative imaging for predicting venous wall invasion status would improve OS for patients with RCC extending into venous systems.

De novo minimal change disease after ABO-incompatible kidney transplantation.

We report the clinical and pathological findings of a case of de novo minimal change disease (MCD) after ABO-incompatible living kidney transplantation. A 62-yr-old man with end-stage renal disease associated with type I diabetes received ABO-incompatible kidney transplantation from his 58-yr-old wife. Although allograft function was excellent immediately after surgery, massive proteinuria (35 g/d) appeared on post-transplantation day 5. After the allograft biopsy taken on post-transplantation day 6, he was treated with 12 cycles of plasma exchange, but the nephrotic-range proteinuria showed no remission. The biopsy specimen showed no significant pathological findings on light microscopy, but electron microscopy showed diffuse effacement of podocyte foot processes. Based on the diagnosis of de novo MCD, the patient received intravenous methylprednisolone pulse therapy, followed by high-dose steroid maintenance therapy. The steroid therapy induced complete remission of nephrotic syndrome and stable allograft function immediately, which was also maintained at one yr after the transplantation.

A case of early recurrent immunoglobulin A nephropathy and T-cell-mediated rejection in a transplant patient with Wiskott-Aldrich syndrome.

Wiskott-Aldrich syndrome (WAS) is an X-chromosome recessive immunodeficiency disease characterized by the triad of thrombocytopenia, eczema, and susceptibility to infection owing to WAS protein gene abnormalities. Kidney transplantation is rarely offered to WAS patients with end-stage renal disease because of concerns that thrombocytopenia and immune disorders may affect the clinical outcome. Here, we report the case of a 20-year-old kidney transplant patient who developed end-stage renal disease owing to immunoglobulin (Ig)A nephropathy caused by WAS. Despite recurrent IgA nephropathy and T-cell-mediated rejection 7 months after transplantation, two rounds of steroid pulse therapy attenuated his renal function and urinary abnormality. His serum creatinine level was maintained at approximately 1.5 mg/dL 1 year after transplantation. No other WAS-related complications were observed throughout the clinical course. Although WAS can cause poor prognosis in kidney transplant patients, careful follow-up may allow kidney transplantation to be performed.

Prediction of Nonadherence and Renal Prognosis by Pre-Transplantation Serum Phosphate Levels.

BACKGROUND Identifying characteristics of patients at high risk of poor adherence before transplantation would be advantageous. However, the optimal approach for characterizing such patients remains unknown. We aimed to evaluate the association between factors for hemodialysis nonadherence and post-transplant renal prognosis. We hypothesized that these factors would influence post-transplantation adherence and worsen renal prognosis. MATERIAL AND METHODS We reviewed patients on hemodialysis who underwent kidney transplantation at our hospital between 2000 and 2017 to identify risk factors associated with poor prognosis. The patients' background and pre-transplantation data, known hemodialysis nonadherence factors, serum phosphate and potassium levels, and interdialytic weight gains were evaluated. The primary endpoint was renal death. We also evaluated the fluctuation of calcineurin inhibitor concentration and weight gain after transplantation. RESULTS Seventy-seven patients were eligible, and the mean observational period was 83.2 months (standard deviation, 50.5). Thirteen patients reached the endpoint. Cox proportional hazards regression analysis showed that pre-transplantation serum phosphate level was a risk factor for renal death (p<0.05), while serum potassium levels and weight gain were not. In addition, fluctuation of calcineurin inhibitor concentration was observed in patients with higher phosphate levels before transplantation (p=0.03). Weight gain after transplantation was not associated with the hemodialysis nonadherence factors. CONCLUSIONS High pre-transplantation serum phosphate levels are considered to represent poor drug adherence and/or an unhealthy lifestyle. Patient education that conveys the importance of adhering to medications and provides nutritional guidance is crucial for improving post-transplantation renal prognosis.

Simultaneous determination of mycophenolic acid and its acyl and phenol glucuronide metabolites in human serum by capillary zone electrophoresis.

A simple capillary electrophoretic method was developed for simultaneous determination of mycophenolic acid (MPA) and its metabolites, acyl glucuronide (AcMPAG) and phenol glucuronide (MPAG), in human serum. The method utilized only running buffer in the separation, prior acidification of serum, and extraction with ethyl acetate. Separation was performed by capillary zone electrophoresis using 20 mM sodium acetate-acetic acid (pH 4.9) as running buffer, applied voltage of 15 kV, and UV detection at 217 nm. Each electrophoretic run was completed within 14 min. The optimized method demonstrated good performance concerning specificity, linearity (r>0.998), sensitivity (limit of detection: for MPA, 0.10 microg/ml; for AcMPAG, 0.10 microg/ml; MPAG, 0.42 microg/ml), accuracy (87-108%) and precision (<9.3%). This method was successfully applied to measurements of MPA, AcMPAG, and MPAG in renal transplant patient samples and could be a useful alternative to HPLC-based methods.

Expression of matrix metalloproteinase-7 on cancer cells and tissue endothelial cells in renal cell carcinoma: prognostic implications and clinical significance for invasion and metastasis.

PURPOSE: The expression of matrix metalloproteinase-7 (MMP-7) correlates with the malignant potential of various tumors and patient survival. We investigated the clinical and prognostic significance of MMP-7 expression in cancer cells and endothelial cells in human renal cell carcinoma (RCC). EXPERIMENTAL DESIGN: We reviewed tissue samples of 156 patients with RCC who had undergone radical operation. MMP-7 expression was examined by immunohistochemistry. Sections containing MMP-7-positive vessels were also stained for CD34. The density of MMP-7-positive vessels was determined by a computer-aided image analysis system. Multivariate analysis was done to assess relevant variables for invasion, metastasis, and cause-specific survival. RESULTS: The proportion of MMP-7-expressing tumor cells were significantly higher (P < 0.001) than that of normal cells. MMP-7-positive vessels were considered blood vessels based on staining for CD34, and their density was increased in tumor areas. The proportion of MMP-7-expressing cancer cells and density of MMP-7-positive vessels correlated with grade, pathologic tumor stage, and metastasis. Multivariate analysis showed that MMP-7 expression on cancer cells correlated with pathologic tumor stage only, whereas MMP-7-positive vessel density correlated with metastasis only. The elevated status of MMP-7 in cancer tissues was an independent predictor for cause-specific survival (odds ratio, 8.61; P = 0.040) by multivariate analysis. CONCLUSIONS: Our results showed that MMP-7 influences tumor progression by regulating invasion and angiogenesis. Multivariate analysis showed that MMP-7 status of cancer tissues was strong predictor of poor prognosis. Our results suggest that MMP-7 targeting treatment may be a potential target against RCC.

Expression of cyclooxygenase-2 in renal cell carcinoma: correlation with tumor cell proliferation, apoptosis, angiogenesis, expression of matrix metalloproteinase-2, and survival.

PURPOSE: Cyclooxygenase (COX)-2 plays an important role in tumor cell proliferation, resistance to apoptosis, angiogenesis, and invasion in various malignant tumors. However, the relationships between COX-2 expression and these biological processes, clinicopathological features, and survival rate in patients with renal cell carcinoma are not clear. EXPERIMENTAL DESIGN: Tumor sections surgically removed from 131 patients were examined for COX-2 expression by immunohistochemistry. We also examined Ki-67 labeling index, apoptotic index, microvessel density, and matrix metalloproteinase (MMP)-2 expression, and correlated COX-2 expression with various clinicopathological features and survival. RESULTS: Of 131 sections, 70 (53.4%) were positive for COX-2 expression. COX-2 expression was associated significantly with various clinicopathological features, and correlated with the Ki-67 labeling index, microvessel density, and MMP-2 expression (P < 0.01), but not with the apoptotic index (P = 0.054). COX-2 expression was also identified as an independent risk factor for large tumor size (>7 cm) in multivariate logistic regression model. COX proportional hazards analysis showed that distant metastasis and high T stage were independent prognostic factors [odds ratio (OR), 9.41; 95% confidence interval (CI), 2.16-41.11; P < 0.01 and OR, 5.19; 95% CI, 1.02-26.54; P = 0.048, respectively), whereas COX-2 expression was not (OR, 1.46; 95% CI, 0.24-9.00; P = 0.68). CONCLUSION: COX-2 expression in patients with renal cell carcinoma is associated with several clinicopathological factors, and appeared to play an important role in tumor cell proliferation and MMP-2 expression, but is not a significant prognostic factor.

Donor-specific blood transfusion prolongs cardiac allograft survival in rats by low nitric oxide production and elevated serum levels of prostaglandin E(2).

Donor-specific blood transfusion (DST) improves allograft survival, although the exact mechanism(s) is not completely understood. The purpose of this study was to determine the role of nitric oxide (NO) and prostaglandin E(2) (PGE(2)) in DST-protective effects, using a rat cardiac transplantation model. Lewis rats (RT-1(1)) were transfused with fully allogeneic ACI rats (RT-l(a)) blood (DST group) or Lewis syngeneic blood (ST) through the portal vein 7 days prior to allogeneic cardiac transplantation. Posttransplantation, aminoguanidine (AG)-treated rat received continuous intravenous infusion of AG, an inhibitor of inducible nitric oxide synthase (iNOS). The survival times of grafted hearts were 5.7+/-0.5, 6.8+/-0.8 and 9.2+/-1.2 days in ST, ST/AG, and DST groups (n=6 for each group), respectively. Inhibition of iNOS in ST/AG group prolonged allograft survival, but it was shorter than that in DST rats. Serum nitrite/nitrate levels on postgrafting day 5 were significantly higher in ST than in ST/AG and DST groups, but were similar in ST/AG and DST groups. These results were confirmed by immunohistochemical staining with anti-iNOS antibody. Serum PGE(2) concentrations in DST rats were significantly higher than in ST and ST/AG groups. Our results suggest that DST prolongs graft survival by enhanced production of PGE(2) with a resultant suppression of immune activation. In addition, DST-induced prolongation of graft survival may be partially mediated by NO suppression.

The effectors of killer activity induced by interferon-alpha and gamma in peripheral blood mononuclear cells.

The nature of effectors of interferon (IFN)-alpha or IFN-gamma-induced killer cell activity remains unclear. The aim of this study was to examine killer cell activity induced by IFN-alpha alone, IFN-gamma alone or a combination of both in patients with renal cell carcinoma (RCC) and to determine the phenotypic patterns of these effectors. The study group included 14 patients (12 men and 2 women, median age 64 years, range 36-77) with confirmed RCC. Peripheral blood mononuclear cells (PBMC) from RCC patients or normal volunteers were cultured with IFN-alpha alone, IFN-gamma alone or a combination of both. Cytotoxic activity was assayed against ACHN cells. Subpopulations of effector cells in IFN-induced killer cell activity were characterized by cell sorting. The most effective type of IFN and the optimal concentration of IFN necessary to induce the maximal killer cell activity varied among RCC patients. The killer activity induced by a combination of IFN-alpha and IFN-gamma was significantly greater than that induced by IFN-alpha or IFN-gamma alone. The greatly increased killer activity induced by IFN-alpha and IFN-gamma was seen in the subpopulations CD3(-) CD16(+), CD3(-) CD56(+) and subpopulation CD3(+)CD4(-), CD3(-)CD16(+), CD3(-)CD56(+), CD57(+)CD16(-), respectively. An optimal type of IFN and optimal concentration of IFN seem to increase the effective rate of treatment of RCC. In addition, the role of IFN-alpha seems to be different from that of IFN-gamma in host defense against RCC. A combination treatment with IFN-alpha and IFN-gamma seems to be suitable to increase the effective rate if we could reduce the side effects of IFNs.

[Clinical study of sarcomatoid renal cell carcinoma].

Patients with sarcomatoid renal cell carcinoma are rare and have poor survival. We evaluated 14 patients who had renal cell carcinoma with a sarcomatoid component between 1982 and 2000. There were 9 men and 5 women with a median age of 59.5 years (range 32 to 77). Seven patients had a tumor on the right side and 7 on the left side. Thirteen patients had some symptoms and 11 had metastases at the initial visit. Most of them were stage T4 and high nuclear grade cancer and showed elevated acute phase reactants. There were 7 patients followed by interferon therapy, and the cause-specific 5-year survival rate was less than 10%. We confirmed that renal cell carcinoma with a sarcomatoid component often showed local invasion, distant metastasis and poor prognosis.

Continuous inflammation and ascites 10 months after the initiation of peritoneal dialysis.

A 38-year-old man underwent peritoneal dialysis (PD) in May 2011 due to chronic renal failure with chronic glomerulonephritis. In early February 2012, he underwent laparoscopy to salvage and correct a malpositioned PD catheter. The laparoscopic intra-abdominal findings revealed turbid ascites and multiple fibrin lumps, despite the patient's lack of history of peritonitis. Based on these findings, in addition to the presence of continuous inflammation and ascites, a diagnosis of pre-encapsulating peritoneal sclerosis was suspected, and the treatment was switched from PD to hemodialysis. The administration of prednisolone at a dose of 20 mg/day and peritoneal lavage resulted in a decrease in the ascites and fibrin lumps.

High density of tryptase-positive mast cells in patients with renal cell carcinoma on hemodialysis: correlation with expression of stem cell factor and protease activated receptor-2.

Patients on hemodialysis are at higher risk of renal cell carcinoma probably because of inflammatory and immune system disorders. The aim of this study was to clarify the pathologic roles of 2 phenotypes of mast cells, mast cell tryptase and mast cell chymase, and their correlation with stem cell factor and protease-activated receptor 2 in patients with renal cell carcinoma on hemodialysis. The densities of mast cell tryptase and mast cell chymase and expressions of stem cell factor and protease-activated receptor 2 were examined in 35 patients with hemodialysis-renal cell carcinoma and 39 with non-hemodialysis-renal cell carcinoma who were diagnosed and treated in our hospital. Protein expression was examined by immunohistochemistry. The proliferation index represented the number of Ki-67-positive cells. There were no significant differences in clinicopathologic features between the 2 groups. Mast cell tryptase densities in intratumoral (8.3 per high-power field) and peritumoral areas (8.7 per high-power field) were higher in hemodialysis-renal cell carcinoma than non-hemodialysis-renal cell carcinoma (2.7 and 5.3 per high-power field). No such significant correlations were detected in mast cell chymase. In hemodialysis-renal cell carcinoma, intratumoral mast cell tryptase density correlated with the proliferation index (P = .039 and P = .008, respectively) and also with stem cell factor and protease-activated receptor 2 expression. Our results emphasize the important roles of mast cell tryptase in cancer cell proliferation and recurrence in hemodialysis-renal cell carcinoma. Stem cell factor and protease-activated receptor 2 seem to up-regulate mast cell tryptase functions in these patients. The results suggest collaborative effects of stem cell factor, mast cell tryptase, and protease-activated receptor 2 on the malignant potential of hemodialysis-renal cell carcinoma.

Lingual metastasis as an initial presentation of renal cell carcinoma.

Distant metastasis of malignant neoplasm to the oral soft tissue is extremely rare. We report a case of renal cell carcinoma (RCC) metastasizing to the tongue. A 47-year-old man visited our hospital with chief complaint of a lump on the middle third of the dorsum of his tongue and the lesion fell off from the tongue. Although histopathological diagnosis of the mass was granuloma teleangiectaticum, similar nodule reappeared in the same area 2 weeks later. The second lesion was composed of granuloma teleangiectaticum and aggregation of neoplastic clear cells in ductal arrangement. The clear cells were immunohistochemically positive for EMA and CD10. The abdominal CT scan revealed a 5.5 cm mass in the left kidney, suggesting RCC. Thus, the lingual lesion was consistent with metastatic RCC. There has been no recurrence for 2 years after the radical nephrectomy and local excision of the tongue.