High aldehyde dehydrogenase 1 activity is related to radiation resistance due to activation of AKT signaling after insulin stimulation in prostate cancer.

The association between type 2 diabetes mellitus and prostate cancer is still under investigation, and the relationship between hyperinsulinemia and prostate cancer stem-like cells (CSCs) is elusive. Here, we investigated the function of insulin/AKT signaling in prostate CSCs. We isolated prostate CSCs as aldehyde dehydrogenase 1-high (ALDH1high) cells from the human prostate cancer 22Rv1 cell line using an ALDEFLUOR assay and established several ALDH1high and ALDH1low clones. ALDH1high clones showed high ALDH1 expression which is a putative CSC marker; however, they showed heterogeneity regarding tumorigenicity and resistance to radiation and chemotherapy. Interestingly, all ALDH1high clones showed lower phosphorylated AKT (Ser473) (pAKT) levels than the ALDH1low clones. PI3K/AKT signaling is a key cell survival pathway and we analyzed radiation resistance under AKT signaling activation by insulin. Insulin increased pAKT levels in ALDH1high and ALDH1low cells; the fold increase rate of pAKT was higher in ALDH1high cells than in ALDH1low cells. Insulin induced resistance to radiation and chemotherapy in ALDH1high cells, and the increased levels of pAKT induced by insulin were significantly related to radiation resistance. These results suggest that ALDH1 suppresses baseline pAKT levels, but AKT can be activated by insulin, leading to treatment resistance.

Tumor-infiltrating CD8+ T cells recognize a heterogeneously expressed functional neoantigen in clear cell renal cell carcinoma.

Immune checkpoint inhibitors (ICIs) are used in cancer immunotherapy to block programmed death-1 and cytotoxic T-lymphocyte antigen 4, but the response rate for ICIs is still low and tumor cell heterogeneity is considered to be responsible for resistance to immunotherapy. Tumor-infiltrating lymphocytes (TILs) have an essential role in the anti-tumor effect of cancer immunotherapy; however, the specificity of TILs in renal cell carcinoma (RCC) is elusive. In this study, we analyzed a 58-year-old case with clear cell RCC (ccRCC) with the tumor showing macroscopic and microscopic heterogeneity. The tumor was composed of low-grade and high-grade ccRCC. A tumor cell line (1226 RCC cells) and TILs were isolated from the high-grade ccRCC lesion, and a TIL clone recognized a novel neoantigen peptide (YVVPGSPCL) encoded by a missense mutation of the tensin 1 (TNS1) gene in a human leukocyte antigen-C*03:03-restricted fashion. The TNS1 gene mutation was not detected in the low-grade ccRCC lesion and the TIL clone did not recognized low-grade ccRCC cells. The missense mutation of TNS1 encoding the S1309Y mutation was found to be related to cell migration by gene over-expression. These findings suggest that macroscopically and microscopically heterogenous tumors might show heterogenous gene mutations and reactivity to TILs.

Neuregulin-1-ß1 and γ-secretase play a critical role in sphere-formation and cell survival of urothelial carcinoma cancer stem-like cells.

Previously, we investigated gene expression in a high aldehyde dehydrogenase 1 expression (ALDH1high) population of urothelial carcinoma (UC) cells as UC cancer stem-like cells (CSCs)/cancer-initiating cells (CICs) and found that NRG1 expression was upregulated in ALDH1high cells. NRG1 is a trophic factor that contains an epidermal growth factor (EGF)-like domain that signals by stimulating ERBB receptor tyrosine kinases and the cytoplasmic domain. NRG1 has been determined to be involved in frequent gene fusions with other partners in several malignancies and has a role in carcinogenesis through the NRG1 EGF-like domain and its cognitive receptor ERBBs. We thus aimed to elucidate the function of NRG1 in UC CSCs/CICs in this study. Both NRG1α and NRG1-ß1 were preferentially expressed in ALDH1high cells compared with ALDH1low cells; however, siRNA experiments revealed that NRG1-ß1 but not NRG1-α has a role in sphere formation. The EGF-like domain of NRG1 had a role in sphere formation of UC cells to some extent but was not essential. The intracellular domain of NRG1 did not have a role in sphere-formation. Inhibition of γ-secretase suppressed sphere formation. These findings indicate that cleavage of NRG1-ß1 by γ-secretase plays an important role in UC CSC/CIC proliferation; however, the downstream targets of NRG1-ß1 remain elusive.

[A Case of Prostate Cancer with Multiple Bone Metastasis with High FGF23 Value Indicated by Intractable Hypocalcemia and Hypophosphatemia].

A 53-year-old man was diagnosed with prostate cancer with multiple bone metastasis. Therefore androgen deprivation therapy was initiated. After treatment with denosumab injection for bone metastasis, hypocalcemia and hypophosphatemia occurred. Despite treatment for hypocalcemia with vitamin D and calcium lactate,his serum calcium and phosphate levels were refractory to treatment. The etiology of hypophosphatemia was investigated,and the level of serum fibroblast growth factor 23 (FGF23) was abnormally elevated. Three months after the first measurement of FGF23,the patient died of prostate cancer. Severe hypophosphatemia is a typical manifestation of tumor-induced hypophosphatemic osteomalacia (TIO),which is a paraneoplastic condition, mediated by FGF23 overexpression in most cases. His osteoblastic metastasis,however,did not meet the disease criteria of osteomalacia. Several reports have suggested that excessive FGF23 may mediate both severe hypophosphatemia and aggressive castrationresistant prostate cancer characteristics. Management of serum FGF23 may be a novel therapeutic strategy for castration-resistant prostate cancer with hypophosphatemia.

[Promotion of Diversity in the Academic Field of Urology : Analysis of 10,000 Articles Published in Acta Urologica Japonica during a 65-Year Period].

Gender equality is one of the most important issues in the promotion of diversity. The participation status of female urologists in academic activities has not been clarified. In the present study, we analyzed a total of 10,288 articles published by 58,914 authors in Acta Urologica Japonica since the first issue in 1955 to the present. The author's gender was determined by an application program interface for gender estimation in combination with independent manual confirmation by two researchers. The increasing rate (⊿person/⊿year) of female authors was as low as 0.067 in 1955-79, but increased to 0.400 in 1980-2000 and 0.814 in 2001-20. Over the time periods, the annual total numbers of female authors (person/year) showed an increasing trend from 3.2 in 1955-79 to 16.3 in 1980-2000 and 26.0 in 2001-20. The numbers of female author individuals, the ratio of female authors to all authors and the ratio of publications by female first author to all publications also showed similar trends. These results suggest that gender equality is becoming more prevalent in the academic field of urology. The methods and data of this study are considered to be useful for the promotion of gender equality in the academic field of urology for the future.

Clinical significance of adding 3 Tesla MRI to the algorithm for decision making on neurovascular bundle preservation in radical prostatectomy.

OBJECTIVES: The aim of this study was to evaluate the additional benefit of 3 Tesla magnetic resonance imaging for neurovascular bundle preservation in radical prostatectomy. METHODS: We retrospectively evaluated patients who underwent 3 T magnetic resonance imaging followed by radical prostatectomy from April 2010 through February 2014 in our university. A total of 50 patients (100 prostate sides) were included in the study. The algorithm previously we described and magnetic resonance imaging findings were considered for the decision on neurovascular bundle preservation. A tumor adjacent to the neurovascular bundle or with extracapsular extension of a posterolateral lesion of the prostate on magnetic resonance imaging was considered a contraindication for nerve-sparing radical prostatectomy. Two experienced radiologists evaluated the magnetic resonance imaging findings. Patients who received neoadjuvant hormonal therapy were excluded. All patients underwent ultrasound-guided prostate biopsy with at least 10 cores. RESULTS: Overall, 60 of the 100 neurovascular bundles were preserved according to an algorithm that consisted of the clinical stage, prostate specific antigen, Gleason score and a positive biopsy core in the apex of the prostate. Considering magnetic resonance imaging findings together with the algorithm, six neurovascular bundles were not preserved. The accuracy of predicting a positive surgical margin only by the algorithm was 56 of 60 neurovascular bundle (93.3%). When adding magnetic resonance imaging, the accuracy was 50 of 54 neurovascular bundle (92.3%). CONCLUSIONS: 3 T magnetic resonance imaging provided no additional benefit to our algorithm for neurovascular bundle preservation.

[Cancer stem cells in prostate cancer].

The cancer stem cell (CSC) hypothesis shows that tumors contain a reservoir of self-renewing cells that maintain the tumor. Such cancer cells were first identified in leukemia in the 1990s. These cells appear to be resistant to various therapies and can survive to repopulate the tumor. Therefore, this concept has important therapeutic implications for recurrence and metastasis. In this review, we introduce the CSC hypothesis and the origin, method of identification and functions of prostate CSCs. In addition, we review the therapeutic challenges of targeting prostate CSCs.

Prostate cancer stem-like cells/cancer-initiating cells have an autocrine system of hepatocyte growth factor.

Prostate cancer cells include a small population of cancer stem-like cells (CSCs)/cancer-initiating cells (CICs) that have roles in initiation and progression of the cancer. Recently, we isolated prostate CSCs/CICs as aldehyde dehydrogenase 1-highh (ALDH1(high) ) cells using the ALDEFLUOR assay; however, the molecular mechanisms of prostate CSCs/CICs are still elusive. Prostate CSCs/CICs were isolated as ALDH1(high) cells using the ALDEFLUOR assay, and the gene expression profiles were analyzed using a cDNA microarray and RT-PCR. We found that prostate CSCs/CICs expressed higher levels of growth factors including hepatocyte growth factor (HGF). Hepatocyte growth factor protein expression was confirmed by enzyme linked immunosorbent assay and Western blotting. On the other hand, c-MET HGF receptor was expressed in both CSCs/CICs and non-CSCs/CICs at similar levels. Hepatocyte growth factor and the supernatant of myofibloblasts derived from the prostate augmented prostasphere formation in vitro, and prostasphere formation was inhibited by an anti-HGF antibody. Furthermore, c-MET gene knockdown by siRNA inhibited the prostasphere-forming ability in vitro and tumor-initiating ability in vivo. Taken together, the results indicate that HGF secreted by prostate CSCs/CICs and prostate myofibroblasts has a role in the maintenance of prostate CSCs/CICs in an autocrine and paracrine fashion.

Prognostic impact of the expression of ALDH1 and SOX2 in urothelial cancer of the upper urinary tract.

Aldehyde dehydrogenase 1 (ALDH1) and sex determining region-Y-related high mobility group box 2 (SOX2) have been identified as putative cancer stem-like cell/tumor-initiating cell markers in various cancer tissues. The aim of this study was to elucidate the prognostic impact of these putative cancer stem-like cell/tumor-initiating cell markers in upper urinary tract urothelial cell carcinoma. Immunohistochemical staining for ALDH1 and SOX2 was carried out on archival specimens from 125 patients with upper urinary tract urothelial cell carcinoma who underwent radical nephroureterectomy. The prognostic value of ALDH1 and SOX2 expression and other clinicopathological features was evaluated. On univariate analysis, tumor grade, pathological T stage, pathological N stage, lymphovascular invasion, ALDH1 expression and SOX2 expression were associated with a poor prognosis. On multivariate analysis, the independent factors of prognosis were tumor grade (P=0.014), pathological N stage (P=0.005) and ALDH1 expression (P=0.002). In subgroup analysis, those subgroups with no positive, one positive or two positive results in immunohistochemistry for ALDH1 and SOX2 expression had estimated 5-year cancer-specific survival rates of 80%, 49% and 22%, respectively (P<0.001). Neither ALDH1 nor SOX2 expression correlated with intravesical recurrence after radical nephroureterectomy. These findings suggest that cancer stem-like cells/tumor-initiating cells are linked to more aggressive behavior of upper urinary tract urothelial cell carcinoma, supporting the current cancer stem cell hypothesis. Thus, therapeutic targeting of cancer stem-like cells/tumor-initiating cells in upper urinary tract urothelial cell carcinoma is a future possibility.

Potential survival benefit of anti-apoptosis protein: survivin-derived peptide vaccine with and without interferon alpha therapy for patients with advanced or recurrent urothelial cancer--results from phase I clinical trials.

We previously identified a human leukocyte antigen (HLA)-A24-restricted antigenic peptide, survivin-2B80-88, a member of the inhibitor of apoptosis protein family, recognized by CD8+cytotoxic T lymphocytes (CTL). In a phase I clinical trial of survivin-2B80-88 vaccination for metastatic urothelial cancer (MUC), we achieved clinical and immunological responses with safety. Moreover, our previous study indicated that interferon alpha (IFN α ) enhanced the effects of the vaccine for colorectal cancer. Therefore, we started a new phase I clinical trial of survivin-2B80-88 vaccination with IFN α for MUC patients. Twenty-one patients were enrolled and no severe adverse event was observed. HLA-A24/survivin-2B80-88 tetramer analysis and ELISPOT assay revealed a significant increase in the frequency of the peptide-specific CTLs after vaccination in nine patients. Six patients had stable disease. The effects of IFN α on the vaccination were unclear for MUC. Throughout two trials, 30 MUO patients received survivin-2B80-88 vaccination. Patients receiving the vaccination had significantly better overall survival than a comparable control group of MUO patients without vaccination (P = 0.0009). Survivin-2B80-88 vaccination may be a promising therapy for selected patients with MUC refractory to standard chemotherapy. This trial was registered with UMIN00005859.

Gene expression profiles of prostate cancer stem cells isolated by aldehyde dehydrogenase activity assay.

PURPOSE: Prostate cancer cells include a small population of cancer stem-like/cancer initiating cells, which have roles in cancer initiation and progression. Recently aldehyde dehydrogenase activity was used to isolate stem cells of various cancer and normal cells. We evaluated the aldehyde dehydrogenase activity of the human prostate cancer cell line 22Rv1 (ATCC®) with the ALDEFLUOR® assay and determined its potency as prostate cancer stem-like/cancer initiating cells. MATERIALS AND METHODS: The human prostate cancer cell line 22Rv1 was labeled with ALDEFLUOR reagent and analyzed by flow cytometry. ALDH1(high) and ALDH1(low) cells were isolated and tumorigenicity was evaluated by xenograft transplantation into NOD/SCID mice. Tumor sphere forming ability was evaluated by culturing in a floating condition. Invasion capability was evaluated by the Matrigel™ invasion assay. Gene expression profiling was assessed by microarrays and reverse transcriptase-polymerase chain reaction. RESULTS: ALDH1(high) cells were detected in 6.8% of 22Rv1 cells, which showed significantly higher tumorigenicity than ALDH1(low) cells in NOD/SCID mice (p < 0.05). Gene expression profiling revealed higher expression of the stem cell related genes PROM1 and NKX3-1 in ALDH1(high) cells than in ALDH1(low) cells. ALDH1(high) cells also showed higher invasive capability and sphere forming capability than ALDH1(low) cells. CONCLUSIONS: Results indicate that cancer stem-like/cancer initiating cells are enriched in the ALDH1(high) population of the prostate cancer cell line 22Rv1. This approach may provide a breakthrough to further clarify prostate cancer stem-like/cancer initiating cells. To our knowledge this is the first report of cancer stem-like/cancer initiating cells of 22Rv1 using the aldehyde dehydrogenase activity assay.

Lymph node metastasis mapping in extended lymphadenectomy to the level of the inferior mesenteric artery for bladder cancer.

BACKGROUND: The aim of this study was to evaluate the distribution of lymph node metastasis in extended lymphadenectomy for patients with bladder cancer. METHODS: We analyzed 31 patients who underwent extended lymphadenectomy at radical cystectomy for bladder cancer between April 2008 and February 2010. Specimens were evaluated as 14 separate packages from predesignated anatomical locations. The lymph node mapping was prospectively registered. RESULTS: The median lymph node count was 37 (range 19-68). Ten (32%) patients had lymph node metastasis. The positive rates at each lymph node site were 0% at the left internal iliac, 13% at the left obturator, 3.2% at the left external iliac, 6.5% at the right internal iliac, 10% at the right obturator, 16% at the right external iliac, 3.2% at the left common iliac, 3.2% at the right common iliac and 6.5% at the presacral node. No lymph node metastasis was detected in the Cloquet, paracaval, aortocaval or paraaortic nodes. One (3.2%) patient had a skip metastasis from the left obturator to the presacral node. CONCLUSIONS: Extended lymphadenectomy provides more accurate lymph node staging. We suggest that it is better to perform lymphadenectomy at least below the aortic bifurcation including the presacral node.

New technique with combination of felt, Hem-o-lok and Lapra-Ty for suturing the renal parenchyma in laparoscopic partial nephrectomy.

We reported a new technique for closure of the renal parenchyma in laparoscopic partial nephrectomy, shortening the suturing time. Between 2009 and 2011, 41 patients with renal masses 4 cm or smaller in diameter underwent transabdominal laparoscopic partial nephrectomy by a single surgeon in a single institution. The sutures were carried out using 2-0 vicryl CT-1 with a 1.2 × 1.2 cm piece of felt, and both sutures were temporarily held using a Hem-o-lok. After all sutures (median 3) were completed, they were sequentially fixed by sliding the Hem-o-lok, and then locked using the Lapra-Ty. The median times for suturing the renal parenchyma and ischemic time were 13 min and 28 min, respectively. The arrangement of the wound and hemostasis were good. No patients developed urinoma or postoperative bleeding.

Prostate cancer detection by prebiopsy 3.0-Tesla magnetic resonance imaging.

OBJECTIVES: The diagnostic value of 3.0-Tesla magnetic resonance imaging (MRI) for prostate cancer remains to be determined. The aim of the present study was to assess the features of prostate cancer detectable by prebiopsy 3.0-Tesla MRI. METHODS: From January 2007 through to December 2008, 116 patients who were examined by prebiopsy 3.0-Tesla MRI underwent radical prostatectomy for localized prostate cancer. Prostate specimens were examined to see whether the largest cancer area was the same as the area indicated on the MRI. Univariate and multivariate logistic regression analyses were conducted to identify variables predictive of agreement between MRI and histopathological findings. RESULTS: Sixty-six (56.9%) patients were suspected of having prostate cancer on the basis of MRI findings. In 49 of these patients (74.2%), it was considered that there was agreement between the abnormal area on the MRI and the index tumor. Univariate analysis revealed that there were significant differences in abnormal digital rectal examination, capsular penetration, the diameter of the index tumor of the radical prostatectomy specimen, and the Gleason scores of the biopsy and radical prostatectomy specimens. Multivariate analysis revealed that the Gleason score of the radical prostatectomy specimen was associated with the accurate detection of the prostate cancer by MRI (P = 0.0177). CONCLUSIONS: In conclusion, 3.0-Tesla MRI tends to accurately diagnose prostate cancer with high tumor burden and aggressiveness. Multimodal examination (T2-weighted imaging, dynamic contrast-enhanced imaging, and diffusion-weighted imaging) is recommended for the diagnosis of prostate cancer using 3.0-Tesla MRI.

Dilemma of physician-mothers faced with an increased home burden and clinical duties in the hospital during the COVID-19 pandemic.

PURPOSE: Since December 2019, coronavirus disease 2019 (COVID-19) has spread rapidly across the world. During the pandemic, physicians in our hospital have had to respond both to the issue of treating the patients and the increasing domestic burden associated with social disruption. The purpose of this study was to assess how much the burden on our doctors, especially female doctors, was increasing. MATERIAL AND METHODS: The Physicians' Career Support Committee in Sapporo Medical University conducted a questionnaire survey. The questionnaire inquired about a wide range of subjects with regard to working style and family life during the first and second waves of the COVID-19 pandemic, and was sent to all medical/dental physicians working in Sapporo Medical University. RESULTS: A total of 266 (42.7%) physicians in our hospital responded to our questionnaire and the data for 264 data were analyzed. The total numbers of males, females, and others, including those who did not want to specify, were 178 (67.4%), 82 (31.0%), and 4 (1.5%), respectively. Among them, 62 (23.5%) and 23 (8.7%) answered that their domestic burden was slightly or markedly increased. The increase in the domestic burden showed a significant difference between genders (p = 0.04). Even after correction for background differences using multivariate analysis, being female (p<0.001), having child dependents (p<0.001), and treating COVID-19 patients (p = 0.03) were significantly related to an increased domestic burden. Regarding family style, 58.1% of the physician-fathers were from two-income families (i.e., families with both parents in employment), and they answered that their partner mainly cared for the children. In contrast, 97.3% of physician-mothers were from two-income families, and 94.6% of the physician-mothers had to take care of children by themselves. CONCLUSION: Physician-mothers are caught in a dilemma between an increased home burden and clinical duties in the hospital, with a significantly higher ratio than physician-fathers during the pandemic. As we showed, female doctors could have not continued their careers and take responsible positions in the same way as male doctors. This is a social risk in the timing of a crisis, such as a pandemic.

Rectal injury during laparoscopic radical prostatectomy: detection and management.

Among 294 patients who underwent laparoscopic radical prostatectomy (LRP), five (1.7%) developed complications such as rectal injury (RI) and rectourethral fistula (RUF). In four patients, the RI was immediately repaired by placing two layers of uninterrupted sutures without fecal diversion. The RI in two of these four patients were diagnosed using a transrectally inserted Hegar uterine dilator (26 mm). The remaining patients, who presented with RUF as the primary manifestation, were conservatively managed, and the fistulas closed spontaneously. Most of the RI detected during the operation were managed with primary fistula closure without fecal diversion. In some cases of postoperative RUF, spontaneous closure may occur while the patient is waiting for surgical repair.

Urethral mobility at catheter removal predicts early recovery of urinary continence after radical prostatectomy.

OBJECTIVES: To analyze the clinical parameters correlated with early recovery of urinary continence after radical prostatectomy, focusing especially on urethral mobility during voiding at catheter removal. METHODS: At the time of catheter removal, a voiding cystourethrography was performed in 58 men (median age 69 years, range 55-76) who had undergone radical prostatectomy. The vertical length of urethral movement between voiding and standstill was measured.The correlation between continence status and various clinical parameters, including age, prostate volume, International Prostate Symptom Score, quality of life score and the length of urethral movement was analyzed. RESULTS: An inverse correlation was observed between length of urethral movement and urinary incontinence volume rate (defined as [leakage volume/daily total urine volume] x 100%) on day 7 after catheter removal (r = -0.388, P < 0.05). Classifying patients into two groups according to the length of urethral movement of 2 mm gave the best accuracy for the prediction of postoperative recovery of urinary incontinence with receiver operating characteristic analysis. A statistically significant difference was observed between group 1 (length >or=2 mm) and group 2(<2 mm) for the leakage rate until day 7 after the catheter was removed (P < 0.01). Urethral movement at the time of catheter removal was significantly correlated with early recovery of continence in the two groups (P < 0.05). CONCLUSIONS: Urethral mobility after radical prostatectomy, which can be easily evaluated using voiding cystourethrography, may be a good predictor of early recovery of urinary continence.

Influence of body mass index and total testosterone level on biochemical recurrence following radical prostatectomy.

OBJECTIVE: A high body mass index (BMI) and a low testosterone level were recently reported to be prognostic factors for prostate-specific antigen (PSA) recurrence following radical prostatectomy (RP). The goal of this study was to clarify their relationship and influences on biochemical recurrence after RP. METHODS: We analysed 126 patients whose data, including the pre-operative BMI and pre-operative serum total testosterone level, were available. All patients underwent RP at our institution between March 1998 and April 2006 without any adjuvant therapy or pelvic lymph node metastasis. The Cox proportional hazards model was used for the multivariate analysis regarding PSA recurrence for the variables of age, operation period, BMI, clinical stage, PSA, Gleason's sum, pre-operative serum total testosterone level and margin status. RESULTS: There were no internal correlations among the parameters we used, even between BMI and the total testosterone level. The total testosterone level was not different between two BMI groups (BMI <26.4 and >/=26.4 kg/m(2): the cut-off is the mean + 1 SD). BMI, PSA and Gleason's sum were found to be independent predictors for PSA recurrence through the multivariate analysis. PSA recurrence-free survival rates at 2 years were 77% for BMI <26.4 kg/m(2), and 31% for BMI >/=26.4 kg/m(2) (P = 0.002, log-rank test, 95% CI: 1.489-7.726). CONCLUSIONS: The current study suggests that high BMI independently contributes to PSA recurrence but that the total testosterone level does not. Although the mechanism by which obesity promotes PSA recurrence in RP patients has not been established, careful observation is needed for patients with high BMI.

[Spontaneous renal artery dissection: a case report].

A 65-year-old female was admitted to our hospital complaining of left upper abdominal pain. Although the symptom improved with observation, serum creatinine rose to 2.0 mg/dl. Slight atrophy of the left kidney was seen on abdominal plain computed tomography. In order to examine the possibility of renal infarction from thrombosis with angiography, we consulted the department of cardiovascular medicine. Even though we did not detect thrombosis with left renal angiography or intravascular ultrasound, there was a dissection finding localized at the left renal artery. Based on this finding, we made a diagnosis of spontaneous renal artery dissection and performed stent placement. Spontaneous renal artery dissection is extremely rare and the frequency of occurrence is reported to be less than 0.05%. Recently, however the frequency of detection has risen with the development of clinical imaging. We must keep in mind that the condition has the possibility of leading to renal blood circulation disorders.