Adult genitourinary sarcoma: analysis using hospital-based cancer registry data in Japan.

BACKGROUND: Genitourinary sarcomas are rare in adults and few large-scale studies on adult genitourinary sarcoma are reported. We aimed to elucidate the clinical characteristics, survival outcomes, and prognostic factors for overall survival of adult genitourinary sarcoma in Japan. METHODS: A hospital-based cancer registry data in Japan was used to identify and enroll patients diagnosed with genitourinary sarcoma in 2013. The datasets were registered from 121 institutions. RESULTS: A total of 116 men and 39 women were included, with a median age of 66 years. The most common primary site was the kidney in 47 patients, followed by the paratestis in 36 patients. The most common histological type was liposarcoma in 54 patients, followed by leiomyosarcoma in 25 patients. The 5-year overall survival rates were 57.6%. On univariate analysis, male gender, paratestis as primary organ, and histological subtype of liposarcoma were predictive of favorable survival while primary kidney, bladder, or prostate gland location were predictive of unfavorable survival. On multivariate analysis, primary paratestis was an independent predictor of favorable survival while primary kidney, bladder, or prostate gland were independent predictors of unfavorable survival. CONCLUSIONS: This is the first report showing the clinical characteristics and survival outcomes of adult genitourinary sarcoma in Japan using a real-world large cohort database.

Retroperitoneal sarcoma: a 10-year follow-up analysis using hospital-based cancer registry data in Japan.

OBJECTIVES: We sought clinical characteristics, survival outcomes, and prognostic factors for overall survival of retroperitoneal sarcoma in Japan. METHODS: A Japanese hospital-based cancer registry database with a pivotal 10-year follow-up was used to identify and enroll patients, registered from 106 institutions, diagnosed with retroperitoneal sarcoma in 2008-2009. Treating hospitals were divided by hospital care volume; high-volume hospitals and low-volume hospitals were defined as ≥ 4 and < 4 cases/year, respectively. RESULTS: A total of 91 men and 97 women were included, with a median age of 64 years. The most common histological type was liposarcoma in 101 patients, followed by leiomyosarcoma in 38 patients. The 5-year and 10-year overall survival rates were 44.1 and 28.3%. The majority of patients (n = 152, 80.9%) were treated at low-volume hospitals. High-volume hospital patients had higher 10-year overall survival rates than low-volume hospital patients (51.2% vs 23.2%, P = 0.026). Multivariate analysis revealed age over 60 years, treatment in low-volume hospitals and chemotherapy were independent predictors of unfavorable survival while treatment with surgery was an independent predictor of favorable survival. CONCLUSIONS: The possibility of surgical removal was suggested to be the most important prognostic factor for retroperitoneal sarcoma. Better survival was shown in patients treated at high-volume hospitals in our series.

A new clustering model based on the seminal plasma/serum ratios of multiple trace element concentrations in male patients with subfertility.

Purpose: To investigate whether seminal plasma (SP)/serum ratios of multiple trace elements (TEs) can classify patients with male subfertility. Methods: SP/serum ratios of 20 TEs (lithium, sodium, magnesium, phosphorus, sulfur, potassium, calcium, manganese, iron, cobalt, copper, zinc, arsenic, selenium, rubidium, strontium, molybdenum, cesium, barium, and thallium) were calculated for healthy volunteers (n = 4) and those consulting for male subfertility (n = 245). Volunteer semen samples were collected by split ejaculation into early and subsequent fractions, and SP/serum ratio data were compared between fractions. The patients' SP/serum ratio data were used in an unsupervised clustering analysis and qualitatively compared with the data from the fractions of ejaculation from the volunteers. Semen quality parameters and pregnancy outcomes were compared between patient clusters. Results: The early fraction of volunteers was characterized by lower phosphorus and arsenic and 18 other higher TEs than the subsequent fraction. Cluster analysis classified patients into four distinct clusters, one sharing characteristics with the early fraction and another with the subsequent fraction. One cluster with the early fraction characteristics had significantly lower semen volume and higher pregnancy rates from spontaneous pregnancies or intrauterine insemination. Conclusions: Classification of patients based on SP/serum ratios of multiple TEs represents the dominance of fractions of ejaculation samples.

[A Case of Proliferative Cystitis Discovered as Protruding Lesion during Inspection of Secondary Infertility].

A 42-year-old man visited our hospital complaining of secondary infertility. An abdominal ultrasonography screening incidentally revealed a protruding lesion in the bladder. As the lesion extended from the prostatic urethra and bladder neck, there was a possibility of ejaculation dysfunction after resection of the lesion. Therefore, with the patient's informed consent, sperm cryopreservation was conducted for fertility preservation, and subsequently histological examination was performed by partial transurethral resection of bladder tumor. The pathological findings were proliferative cystitis including all three subtypes (glandularis, cystica, and papillary). Cyclooxygenase-2 immunostaining was positive in cytoplasm; weakly positive in cystic and papillary lesions, and strongly positive in glandular lesions. According to a literature review of massive proliferative cystitis, the patient was the 77th case in Japan. Novel postoperative immunological pharmacotherapies with cyclooxygenase-2 inhibitors have been introduced in recent years.

[Two Cases of Femoral Nerve Palsy after Pelvic Surgery].

Postoperative femoral nerve palsy (FNP) is a rare complication associated with urologic surgery. Inappropriate use of retractors, use of lithotomy position, and prolonged surgery that lead to the femoral nerve compression have been reported as risk factors for FNP. Here, we report two cases of FNP after pelvic surgery. Case 1: A 47-year-old woman underwent ureterocystoneostomy for a giant ureterocele. On the first postoperative day, she developed muscle weakness and paresthesia in the left lower leg. An orthopedic surgeon diagnosed her with FNP associated with the surgery. Case 2: An 82-year-old woman underwent radical cystectomy for invasive bladder cancer. On the second postoperative day, she developed extension deficit in the left lower leg and was diagnosed with an iatrogenic FNP. Although this complication is infrequent, at onset, it leads to difficulty in walking and gait disturbance in the patient. As a result, it greatly reduces the patient's postoperative quality of life. Therefore, preventive measures should be taken to reduce the risk of this postsurgical nerve injury, such as appropriate placement of retractors and proper patient positioning during the operation.

Clinicopathological features of adrenal malignancies: Analysis of hospital-based cancer registry data in Japan.

OBJECTIVE: To identify the clinicopathological features of adrenal malignancies and analyze the prognoses of patients with adrenal cortical carcinoma (ACC) and malignant pheochromocytoma (MPCC). PATIENTS AND METHODS: We used a hospital-based cancer registry data in Japan to extract cases of adrenal malignancies that were histologically confirmed, diagnosed, and initially treated from 2012-2015. For survival analysis, we used data from the 2008-2009 cohort to estimate 5-year overall survival (OS) by the Kaplan-Meier method. RESULTS: A total of 989 adrenal malignancies were identified in the 2012-2015 cohort. The most common histologies were ACC (26.4%), diffuse large B-cell lymphoma (DLBCL; 25.4%), neuroblastoma (22.2%), and MPCC (11.9%). While most ACC and MPCC patients were in their 60s, DLBCL patients accounted for 61.5% of adrenal malignancies in the over-70 cohort. Among ACC patients with clinical staging data, 46.3% of patients were stage IV. Although surgery was a chief strategy for all stages, younger patients tended to receive combination therapy, including surgery and chemotherapy or hormone therapy. In the 2008-2009 cohort, the 5-year OS rates of ACC (n = 49) and MPCC (n = 23) patients were 56.2% and 86.4% while ACC patients without surgery had 1- and 2-year OS rates of 25.0% and 12.5%. CONCLUSION: In Japan, DLBCL accounted for the majority of adrenal malignancies in older patients. Despite advanced staging, ACC patients were mainly treated with surgery and their prognosis was not satisfactory. Such epidemiological data may be useful in considering initial management strategies.

[Adrenocortical Oncocytic Tumor : A Report of Two Cases].

Adrenocortical oncocytic tumors are rare. As the Weiss criteria overestimate the malignancy of oncocytic tumor due to histological hallmarks, the Lin-Weiss-Bisceglia system (LWB system) is required for an accurate diagnosis of the malignant potential of an oncocytic tumor. We report two cases diagnosed as an oncocytic tumor with uncertain malignant potential (borderline) and an oncocytic tumor (benign) based on the LWB system, both of which were diagnosed as malignant based on the Weiss criteria. Case 1 : A man in his 20s was referred to our hospital for treatment of a left adrenal tumor. A non-functional pheochromocytoma or adrenal cancer was suspected. He underwent surgical resection of the left adrenal tumor and left kidney. The specimen was positive for 3 of the 9 Weiss criteria, but met one minor criterion in the LWB system. He was diagnosed with an oncocytic tumor with uncertain malignant potential (borderline). Case 2 : A woman in her 40s was referred to our hospital for treatment of a left adrenal tumor. Under the possibility of adrenal cancer, she underwent surgical resection of the left adrenal tumor. The specimen was positive for 3 of the 9 Weiss criteria, but the specimen met no criteria in the LWB system. She was diagnosed with an oncocytic tumor (benign). There has been no recurrence of the oncocytic tumor as of 2 years of follow-up in the two patients.

[Maturation and Development of the"All Japan E-Learning Cloud of the Training Program for Oncology Professionals].

This paper reports the 5-year operational status of the third phase of the"All Japan E-Learning Cloud of the Training Program for Oncology Professionals"by tabulating the viewing trends of available lecture contents. In this phase, the goal was to train cancer genome medical professionals in this new, advanced medical technology field as well as train personnel to treat rarely encountered pediatric, adolescent/young adult, and other life stage cancers. Additionally, new lecture items have been added to the e-learning cloud in collaboration with 7 oncology specialist centers, contributing to the development of human capital in cancer care(including graduate student education)and faculty development for local medical professionals.

Discrepancy between clinical and pathological T stages in upper urinary tract urothelial carcinoma: Analysis of the Hospital-Based Cancer Registry data in Japan.

OBJECTIVE: To examine the discrepancy between clinical and pathological T stages in patients with urothelial carcinoma of the upper urinary tract treated with radical surgery, and to compare them with the corresponding discrepancy in urothelial carcinoma of the bladder. METHODS: We used the Hospital-Based Cancer Registry data in Japan to extract urothelial carcinoma of the bladder cases (n = 3747) and urothelial carcinoma of the upper urinary tract cases (n = 6831), including urothelial carcinoma of the renal pelvis (n = 3295) and urothelial carcinoma of the ureter (n = 3536) with cT1-4N0M0 diagnosed in 2012-2015, histologically confirmed, and treated with radical surgery without chemotherapy or radiotherapy. We compared the T-stage discrepancy among different tumor locations. RESULTS: The proportions of overall T-stage discrepancy in the urothelial carcinoma of the renal pelvis (40.8%) and urothelial carcinoma of the ureter (42.9%) groups tended to be higher compared with that in the urothelial carcinoma of the bladder (38.8%) group. The upstaging rate from clinical non-muscle-invasive cancer (≤cT1) to pathological muscle-invasive cancer (≥pT2) was significantly higher in the urothelial carcinoma of the renal pelvis and urothelial carcinoma of the ureter groups compared with the urothelial carcinoma of the bladder group (P = 0.002, P < 0.0001, respectively). Upstaging from clinical organ-confined disease (≤cT2) to pathological non-organ-confined disease (≥pT3) was significantly more frequent in the urothelial carcinoma of the renal pelvis (27.8%, P < 0.0001) and urothelial carcinoma of the ureter (22.3%, P < 0.0001) groups compared with the urothelial carcinoma of the bladder (17.8%) group. CONCLUSION: Discrepancy in T staging is significantly higher in patients with urothelial carcinoma of the upper urinary tract compared with those with urothelial carcinoma of the bladder, especially in those with organ-confined disease. As T-stage discrepancy might lead to missed opportunities to carry out perioperative treatment, more accurate diagnostic techniques are required to identify the appropriate urothelial carcinoma candidates for preoperative treatment.

Prognostic impact of non-urothelial carcinoma of the upper urinary tract: Analysis of hospital-based cancer registry data in Japan.

OBJECTIVES: To identify the prognosis of patients with non-urothelial carcinoma of the upper urinary tract and compare it with that of patients with urothelial carcinoma. METHODS: We used hospital-based cancer registry data in Japan to extract histologically confirmed non-urothelial carcinoma and urothelial carcinoma cases of the upper urinary tract diagnosed in 2008-2009. We estimated the 5-year overall survival by a Kaplan-Meier analysis. The Cox proportional hazards regression analysis was used to evaluate prognostic factors. RESULTS: A total of 2567 upper urinary tract cancer patients with confirmed histological subtypes were identified. The most common histology of non-urothelial carcinoma was squamous cell carcinoma (n = 88, 3.4%) followed by adenocarcinoma (n = 33, 1.3%) and small cell carcinoma (n = 10, 0.4%). The proportion of advanced stage in the squamous cell carcinoma patients was significantly higher than that in the urothelial carcinoma patients (P = 0.003). In stage IV, the proportion of patients who received a combination of surgery + chemotherapy in the urothelial carcinoma group was higher than that in the non-urothelial carcinoma group (34% vs 16%, respectively). The 5-year overall survival rates of the non-urothelial carcinoma patients at stages I-III and stage IV were significantly worse than those of the urothelial carcinoma patients (P = 0.003, P < 0.001, respectively). In multivariate analyses, age ≥73 years, advanced stage (stage IV), tumor location (ureter) and the presence of non-urothelial carcinoma histology were independent poor prognosis factors. CONCLUSION: The prognosis of non-urothelial carcinoma patients is worse than that of urothelial carcinoma patients, especially for non-urothelial carcinoma patients at stage IV. More effective systemic therapies are required to improve these patients' oncological outcomes.

Fertility and reproductive technology use in testicular cancer survivors in Japan: A multi-institutional, cross-sectional study.

OBJECTIVE: To evaluate fertility and use of reproductive technology of testicular cancer survivors in a multi-institutional, cross-sectional study. METHODS: This study recruited testicular cancer survivors who were followed after treatment for testicular cancer at eight high-volume institutions between 2018 and 2019. The participants completed the questionnaires on marital status, fertility and use of reproductive technology. RESULTS: A total of 567 testicular cancer survivors, with a median age of 43 years, responded to the questionnaire. Chemotherapy was given to 398 survivors, including three cycles of cisplatin-based chemotherapy in 106 patients and four cycles in 147 patients. Among 153 survivors who attempted sperm cryopreservation, 133 (87%) could preserve sperm. Of the 28 survivors whose cryopreserved sperm was used, 17 (61%) fathered children. Of the 72 survivors who fathered children without the use of cryopreserved sperm, 59 (82%) fathered naturally. Whereas 33 (20%) of 169 survivors treated without chemotherapy fathered children without using cryopreserved sperm, 39 (10%) of 398 treated with chemotherapy fathered children (P < 0.05). Furthermore, the paternity rate was 12% and 5% in testicular cancer survivors with three and four cycles of cisplatin-based chemotherapy, respectively (P < 0.05). However, of 121 survivors who wanted to have children, 14 (12%) received counseling about infertility treatment. CONCLUSIONS: Testicular cancer survivors preserving their sperm have a higher paternity rate after chemotherapy, especially after four cycles, than those not using cryopreserved sperm. Physicians who give chemotherapy for testicular cancer need to take particular care not only with respect to recurrence of testicular cancer, but also to post-treatment fertility.

[A Case of Perfusion Failure of Peritoneal Dialysis Catheter Treated by Reduced Port Surgery].

A 17-year-old man received continuous ambulatory peritoneal dialysis (CAPD) catheter implantation and had started peritoneal dialysis. Perfusion failure of peritoneal dialysis catheter occurred one month after the catheter implantation. Transcatheter contrast examination revealed catheter obstruction about 4-5 cm from the catheter tip. We performed reduced port surgery to remove the obstruction. Laparoscopy revealed that the omentum was adhered to the abdominal wall and wrapped the catheter. We diagnosed the cause of catheter malfunction as omentum wrapping. We removed the omentum from the catheter, and repositioned the catheter into the Douglas fossa. Although CAPD worked successfully after the operation, perfusion failure recurred one month after the operation. The patient requested discontinuation of CAPD and change to hemodialysis. Therefore, we removed the CAPD catheter. The catheter was adhered to the omentum. Reduced port surgery for peritoneal dialysis catheter obstruction has the advantage of being minimally invasive and is a reliable procedure, but further studies are needed to reduce the recurrence rate of perfusion failure and to establish the procedure after perfusion failure.

Genome-wide association study of semen volume, sperm concentration, testis size, and plasma inhibin B levels.

Semen quality is affected by environmental factors, endocrine function abnormalities, and genetic factors. A GWAS recently identified ERBB4 at 2q34 as a genetic locus associated with sperm motility. However, GWASs for human semen volume and sperm concentration have not been conducted. In addition, testis size also reportedly correlates with semen quality, and it is important to identify genes that affect testis size. Reproductive hormones also play an important role in spermatogenesis. To date, genetic loci associated with plasma testosterone, sex hormone-binding globulin (SHBG), follicle-stimulating hormone (FSH), and luteinizing hormone (LH) levels have been identified using GWASs. However, GWASs have not identified any relevant loci for plasma inhibin B levels. We conducted a two-stage GWAS using 811 Japanese men in a discovery stage followed by a replication stage using an additional 721 Japanese men. The results of the discovery and replication stages were combined into a meta-analysis. After setting a suggestive significance threshold for P values < 5 × 10-6　in the discovery stage, we identified ten regions with SNPs (semen volume: one, sperm concentration: three, testes size: two, and inhibin B: four). We selected only the most significant SNP in each region for replication genotyping. Combined discovery and replication results in the meta-analysis showed that the locus 12q21.31 associated with plasma inhibin B levels (rs11116724) had the most significant association (P = 5.7 × 10-8). The LRRIQ1 and TSPAN19 genes are located in the 12q21.31 region. This study provides new susceptibility variants that contribute to plasma inhibin B levels.

Prognostic significance of non-urothelial carcinoma of bladder: analysis of nationwide hospital-based cancer registry data in Japan.

OBJECTIVES: To identify the prognosis of pure non-urothelial carcinoma (non-UC) of bladder and to compare them with those of pure urothelial carcinoma (UC). METHODS: We used Japan's nationwide hospital-based cancer registry data to extract histologically confirmed pure non-UC and UC cases of bladder diagnosed in 2008-2009. We estimated the 5-year overall survival (OS) by a Kaplan-Meier analysis. RESULTS: A total of 8094 patients with confirmed histological subtypes of bladder cancer were identified. The most common pure non-UC was squamous cell carcinoma (SQ, n = 192, 2.4%) followed by adenocarcinoma (AC, n = 138, 1.7%) and small cell neuroendocrine carcinoma (SmC, n = 54, 0.7%). The proportion of female patients (48%) was significantly higher in the SQ group compared with the pure UC group (P < 0.001). The 5-year OS rate of the non-UC patients was significantly worse than that of the UC patients (40 vs. 61%, P < 0.001). According to stages, the 5-year OS rates of the stage I and III non-UC patients were significantly worse than those of the UC patients (P = 0.001). Considering histologic subtypes and stages, the 5-year OS rates of the stage I SQ patients were worse than those of the AC and SmC patients (46, 68 and 64%, respectively). CONCLUSION: The prognosis of pure non-UC was worse than that of pure UC, especially in the stage I and III non-UC patients. To improve these patients' oncologic outcomes, a more aggressive surgical approach may be necessary in stage I patients with non-UC, especially in pure SQ.

Recent malignant testicular tumor trend in Japan, a country with an aging population: a large-scale study of 2012-2015 hospital-based cancer registry data.

OBJECTIVE: Japan's national database of hospital-based cancer registries is estimated to cover ~67% of all new cancer cases. Using this database, we analyzed the characteristics of the recently diagnosed testicular malignancy. METHODS: We obtained data for 6510 adult testicular malignancy patients diagnosed in 2012-2015. The distributions of patient ages, histological diagnoses and testicular germ cell tumor hospital care volumes were determined. RESULTS: The most common histology was seminoma (60.3% of all testicular malignancies), followed by non-seminoma (24.1%) and diffuse large B-cell lymphoma (13.1%). The median and mean ages of the testicular germ cell tumor patients were high at 38 and 39.8 years, respectively. The age distribution peaked at 30-40 years, followed by 40-50 years. Approximately 18% of testicular germ cell tumor patients were ≥50 years. The ages of the diffuse large B-cell lymphoma patients peaked at 70-80 years (mean 67.7 years). When the analysis was limited to the testicular germ cell tumor patients who received first-course cancer treatment at the participating hospitals, the number of high-volume hospitals with ≥20 testicular germ cell tumor care volume was limited to 61 (10.0% of the 605 hospitals that treated ≥1 testicular germ cell tumor patient). However, when the patients who changed hospitals during treatment or relapsed after treatment completion were analyzed together, the number of high-volume hospitals increased to 104 (17.0% of 612 hospitals). CONCLUSION: The testicular germ cell tumor patients' mean age was nearly 40 years. The proportions of older testicular germ cell tumor patients and diffuse large B-cell lymphoma patients were higher than previously thought. The reasons for this trend are unknown, but it is important to address the trend identified herein in a country with a super-aging population.

Impact of centralization in primary retroperitoneal sarcoma treatment: analysis using hospital-based cancer registry data in Japan.

BACKGROUND: To elucidate the clinicopathological features, hospital-based care volume and prognoses associated with primary retroperitoneal sarcoma (PRS). METHODS: Clinical data on PRS cases, diagnosed from 2008 to 2009 (cohort A) and from 2012 to 2015 (cohort B), were obtained from the national hospital-based cancer registry in Japan. Since data on survival, 5 years after PRS diagnosis, were available only for cohort A, patient prognoses were analyzed in this group alone. RESULTS: The numbers of participating hospitals were 154 in cohort A and 537 in cohort B. In total, 380 and 2011 patients with PRS were identified in cohorts A and B, respectively. The incidence of PRS among all the registered urogenital malignancies was 0.52% (2391/462,866). Liposarcoma was the most commonly observed PRS subtype (55.8%), followed by leiomyosarcoma (19.0%). In cohort A, the 5-year overall survival (OS) was 40.4%. The 5-year OS associated with stage I (n = 107), stages II and III (n = 61), and stage IV (n = 59) disease were 59%, 39%, and 6%, respectively. Only two institutions treated over ten patients per year in each cohort. When institutions were divided by hospital care volume (8 hospitals with ≥ = 3 cases and 149 with < 3 cases/year), there were any statistic differences in the OS. CONCLUSIONS: We presented the distribution and prognoses associated with PRS using a real-world large cohort database. Centralization for PRS management was not established in Japan, while the prognosis did not significantly depend on the treatment volume of hospitals.

Characteristics of penile cancer in Japan: An analysis of nationwide hospital-based cancer registry data.

OBJECTIVES: To investigate the clinical characteristics of patients with penile cancer in Japan using the nationwide hospital-based cancer registry database. METHODS: Using hospital-based cancer registry data, we described the distribution of age, pathology, tumor-node-metastases classification, and first-course treatment in patients treated between 2012 and 2015. We compared the patterns of first-line treatment between elderly and non-elderly patients. RESULTS: A total of 1012 patients were diagnosed with squamous cell carcinoma among 1773 patients with penile tumors who registered under topography code C60. The median age at diagnosis was 74 years, and 85.9% of patients were aged >60 years. The most common pathology was usual-type squamous cell carcinoma (91.9%), followed by verrucous carcinoma (5.0%), sarcomatoid carcinoma (1.1%), papillary carcinoma (0.7%), basaloid carcinoma (0.6%), adenosquamous carcinoma (0.4%), warty carcinoma (0.2%) and mixed carcinoma (0.1%). A total of 61.3% of patients were diagnosed with localized disease. In contrast, the proportions of patients with lymph node and distant metastases were 27.5% and 2.1% at diagnosis, respectively. The proportion of patients who were treated with chemotherapy as the first-course treatment was significantly lower among elderly patients (≥80 years) with clinical stage III (27.6% vs 7.1%, P = 0.0312) and clinical stage IV (53.2% vs 14.3%, P = 0.0086). CONCLUSIONS: Most penile cancer patients in Japan are diagnosed with usual-type squamous cell carcinoma, and those with human papilloma virus-related squamous cell carcinomas are <1%. Chemotherapy for advanced penile cancer is administered less in Japanese elderly (≥80 years) patients.

Clinicopathological features of malignant urachal tumor: A hospital-based cancer registry data in Japan.

OBJECTIVES: To identify the clinicopathological features of malignant urachal tumor in Japan, and analyze the 5-year overall survival of malignant urachal tumor patients. METHODS: We used the hospital-based cancer registry data to extract malignant urachal tumor cases that were diagnosed in 2008-2009 and 2012-2015, histologically confirmed, and received the first course of treatment. We analyzed the 5-year overall survival using the 2008-2009 cohort's data. RESULTS: We identified 456 patients, and malignant urachal tumor accounted for 0.4% of all malignant bladder cancers. The median age was 61 years (range 2-97), and 66% were men. The most common histology was adenocarcinoma (80%), followed by urothelial carcinoma (11%) and squamous cell carcinoma (3%). The proportions of patients were: 19% Ta/Tis/T1N0M0, 55% T2-3N0M0, 13% T4/N+ and 13% M+. Regarding the initial treatment, the proportions of surgery alone were 79% and 33% in cases of T3 or less N0M0 and T4/N+, respectively. The proportion of combination therapy including surgery and chemotherapy were 13% and 44% in T2-3N0M0 and T4/N+, respectively. Radiation therapy was not common at any stage. In the 2008-2009 cohort, the 5-year overall survival rate in Ta/Tis/T1N0M0, T2-3N0M0, T4/N+ and M+ were 60%, 64%, 63% and 12%, respectively. CONCLUSIONS: Malignant urachal tumors are quite rare in Japan, and most of those without metastasis are likely to be treated by surgery alone, even at advanced stages. A standard of care must be established for malignant urachal tumor patients at advanced stages or with metastasis, as the prognosis of these patients can be poor.

[A Case of Retroperitoneal Bronchogenic Cyst Successfully Resected with Retroperitoneoscopic Surgery].

A 32-year-old woman was referred to our hospital for consultation with a suspected left adrenal tumor detected by ultrasonography at a health check. Computed tomography and magnetic resonance imaging revealed a 3×1×4 cm multilocular cystic mass arising from the diaphragmatic crura, suggesting a retroperitoneal bronchogenic cyst. The patient underwent excision of the cyst and adjacent diaphragm using a retroperitoneoscopic approach. Retroperitoneal bronchogenic cysts are rare. We review the cases of 26 patients who underwent laparoscopic resection of a retroperitoneal bronchogenic cyst.

[A Case of Renal Angiomyolipoma with Tumor Thrombus Invading the Inferior Vena Cava].

A 64-year-old man with flank pain was diagnosed with right renal angiomyolipoma (AML) with tumor thrombus invading the inferior vena cava (IVC). Computed tomography showed a 55 mm IVC tumor thrombus with fat density. The patient underwent radical nephrectomy and IVC thrombcetomy with uneventful postoperative recovery. Pathological diagnosis was AML without malignancy. No recurrence has been observed for 18 months after surgery. We reviewed 60 case reports of AML with venous involvement. Furthermore, we discussed differential diagnosis between AML and other renal tumors mimicking AML with caval involvement.