Impact of prostate position-based image-guidance in intensity-modulated radiation therapy for localized prostate cancer.

BACKGROUND/PURPOSE: The long-term clinical impact of prostate position-based image-guided radiotherapy (IGRT) for localized prostate cancer remains unclear. MATERIALS AND METHODS: We retrospectively compared clinical outcomes following intensity-modulated radiation therapy (IMRT) with cone-beam computed tomography-based prostate position-based IGRT (P-IGRT) or without P-IGRT (non-P-IGRT). From June 2011, we applied P-IGRT in IMRT for intermediate-risk (IR) prostate cancer (PCa) (D'Amico risk classification) (76 Gy in 38 fractions, with smaller margins). Clinical outcomes of patients who received P-IGRT between June 2011 and June 2019 were retrospectively compared with those of patients with IR PCa who received IMRT without P-IGRT between October 2002 and May 2011 in our institution (74 Gy in 37 fractions). RESULTS: A total of 222 consecutive patients were analyzed: 114 in the P-IGRT cohort and 108 in the non-P-IGRT cohort. The median follow-up period after IMRT was 7.1 years for the P-IGRT cohort and 10.8 years for the non-P-IGRT cohort. The biochemical failure-free rate was significantly better in the P-IGRT cohort (94.9% for the P-IGRT cohort vs 82.7% for the non-P-IGRT cohort at 10 years, p = 0.041). The rate of rectal bleeding which needs intervention including the use of suppositories was significantly lower in the P-IGRT cohort (p < 0.001). CONCLUSIONS: The use of P-IGRT with higher doses and smaller margins was correlated with significantly better biochemical control, and a lower incidence of rectal bleeding in IMRT for intermediate-risk prostate cancer. The enhanced accuracy using P-IGRT has the potential to independently improve disease control and reduce late rectal bleeding.

Clinical factors predicting the outcome of salvage radiotherapy for patients with biochemical recurrence after radical prostatectomy.

BACKGROUND: It remains unclear which patients with biochemical recurrence after prostatectomy are most suitable for salvage radiotherapy. We evaluated the parameters related to outcomes. METHODS: We retrospectively evaluated patients who underwent salvage therapy for biochemical recurrence after prostatectomy between 2005 and 2019. This study aimed to evaluate biochemical recurrence-free survival (bRFS) after salvage radiotherapy and elucidate the parameters associated with bRFS. The bRFS rate was calculated using the Kaplan-Meier method, and the parameters associated with bRFS were evaluated using Cox regression analysis. RESULTS: This study included 67 patients treated with salvage radiotherapy with a median age of 67 years at salvage radiotherapy. The median follow-up period after salvage radiotherapy was 7.3 years. The 5-year bRFS rate following salvage radiotherapy was 47.1%. Univariate analysis showed that PSA doubling time < 6 months, positive surgical margin, and pathological Gleason score ≥ 8 were significantly associated with shorter bRFS (p < 0.001, p = 0.036, p = 0.047, respectively). Multivariable analysis showed that a PSA doubling time < 6 months and positive surgical margins were significantly associated with shorter bRFS (p = 0.001 and p = 0.018, respectively). No serious adverse events were observed. CONCLUSIONS: In our hospital, approximately half of the patients are under long-term control with salvage radiotherapy. A PSA doubling time of < 6 months and positive surgical margins were suggested to be associated with poor outcomes of salvage radiotherapy.

Real-world sequential treatment patterns and clinical outcomes among patients with advanced urothelial carcinoma in Japan.

OBJECTIVES: Immune checkpoint inhibitors and enfortumab vedotin have opened new avenues for sequential treatment strategies for locally advanced/metastatic urothelial carcinoma (la/mUC). In the pre-enfortumab vedotin era, many patients could not receive third-line treatment owing to rapid disease progression and poor general status. This study aimed to analyze real-world sequential treatment practices for la/mUC in Japan, with a focus on patients who do not receive third-line treatment. METHODS: We analyzed data for 1023 la/mUC patients diagnosed between January 2020 and December 2021 at 54 institutions from a Japanese nationwide cohort. RESULTS: At the median follow-up of 28.5 months, the median overall survival from first-line initiation for 905 patients who received systemic anticancer treatment was 19.1 months. Among them, 81% and 32% received second- and third-line treatment. Notably, 52% had their treatment terminated before the opportunity for third-line treatment. Multivariate logistic regression analysis revealed that low performance status (≥1), elevated neutrophil-to-lymphocyte ratio (≥3), and low body mass index (<21 kg/m2) at the start of first-line treatment were independent risk factors for not proceeding to third-line treatment (p = 0.0024, 0.0069, and 0.0058, respectively). In this cohort, 33% had one of these factors, 36% had two, and 15% had all three. CONCLUSIONS: This study highlights the high frequency of factors associated with poor tolerance to anticancer treatment in la/mUC patients. The findings suggest the need to establish optimal sequential treatment strategies, maximizing efficacy within time and tolerance constraints, while concurrently providing strong supportive care, considering immunological and nutritional aspects.

Current trends in the promising immune checkpoint inhibition and radiotherapy combination for locally advanced and metastatic urothelial carcinoma.

Locally advanced and metastatic urothelial carcinoma (UC) remains a challenging malignancy, though several novel therapeutic drugs have been developed in recent years. Over the past decade, immune checkpoint inhibitors (ICI) have shifted the paradigm of therapeutic strategies for UC; however, only a limited number of patients respond to ICI. Since radiotherapy (RT) is widely known to induce systemic immune activation, it may boost the efficacy of ICI. Conversely, RT also causes exhaustion of cytotoxic T cells, and the activation and recruitment of immunosuppressive cells; ICI may help overcome these immunosuppressive effects. Therefore, the combination of ICI and RT has attracted attention in recent years. The therapeutic benefits of this combination therapy and its optimal regimen have not yet been determined through prospective studies. Therefore, this review article aimed to provide an overview of the current preclinical and clinical studies that illustrate the underlying mechanisms and explore the optimization of the RT regimen along with the ICI and RT combination sequence. We also analyzed ongoing prospective studies on ICI and RT combination therapies for metastatic UC. We noted that the tumor response to ICI and RT combination seemingly differs among cancer types. Thus, our findings highlight the need for well-designed prospective trials to determine the optimal combination of ICI and RT for locally advanced and metastatic UC.

Real-world outcomes of pembrolizumab for platinum-refractory advanced urothelial carcinoma: Efficacy, safety, and evidence for trial-unfit patients.

Pembrolizumab, monoclonal antibody targeting programmed cell death 1, is widely used for platinum-refractory urothelial carcinoma (UC) patients. Although the survival benefit of pembrolizumab was proven in the well-designed phase III trial, these data represent only a part of patients due to strictly defined eligibility criteria. The patients' characteristics in the clinical practice are much more heterogenous than those of trial participants. The real-world experience is useful to validate the trial result and find suitable candidates for the treatment. Similarly, real-world data plays a significant role in addressing the efficacy and safety of special populations, such as poor performance status or older patients. This review summarizes the real-world evidence on pembrolizumab for platinum-refractory UCs and discusses the clinical risk factors and efficacy for trial-ineligible patients.

MRI/RNA-Seq-Based Radiogenomics and Artificial Intelligence for More Accurate Staging of Muscle-Invasive Bladder Cancer.

Accurate staging of bladder cancer assists in identifying optimal treatment (e.g., transurethral resection vs. radical cystectomy vs. bladder preservation). However, currently, about one-third of patients are over-staged and one-third are under-staged. There is a pressing need for a more accurate staging modality to evaluate patients with bladder cancer to assist clinical decision-making. We hypothesize that MRI/RNA-seq-based radiogenomics and artificial intelligence can more accurately stage bladder cancer. A total of 40 magnetic resonance imaging (MRI) and matched formalin-fixed paraffin-embedded (FFPE) tissues were available for analysis. Twenty-eight (28) MRI and their matched FFPE tissues were available for training analysis, and 12 matched MRI and FFPE tissues were used for validation. FFPE samples were subjected to bulk RNA-seq, followed by bioinformatics analysis. In the radiomics, several hundred image-based features from bladder tumors in MRI were extracted and analyzed. Overall, the model obtained mean sensitivity, specificity, and accuracy of 94%, 88%, and 92%, respectively, in differentiating intra- vs. extra-bladder cancer. The proposed model demonstrated improvement in the three matrices by 17%, 33%, and 25% and 17%, 16%, and 17% as compared to the genetic- and radiomic-based models alone, respectively. The radiogenomics of bladder cancer provides insight into discriminative features capable of more accurately staging bladder cancer. Additional studies are underway.

Morphological and molecular characterization of a new species of the genus Echinorhynchus Zoega in Müller, 1776 (Acanthocephala: Echinorhynchidae) parasitizing the rock greenling Hexagrammos lagocephalus (Pallas) (Scorpaeniformes: Hexagrammidae) from eastern Hokkaido, Japan.

A new species of marine-fish-parasitizing echinorhynchid palaeacanthocephalan, Echinorhynchus sasakiae sp. nov., is described based on material from the intestine of the rock greenling Hexagrammos lagocephalus (Pallas) obtained in two localities (Akkeshi and Nemuro) in Hokkaido, northern Japan. Echinorhynchus sasakiae sp. nov. can be distinguished from other congeners by having an oval-shaped proboscis covered with hooks arranged in 14-15 rows, each consisting of 7-10 hooks that are anteriorly short and curved, but posteriorly long and weakly curved. The phylogenetic position of Echinorhynchus sasakiae sp. nov. is inferred based on three gene markers (cytochrome c oxidase subunit I, 18S rRNA, and 28S rRNA) along with relevant sequences from ten congeners available in public databases. Echinorhynchus sasakiae sp. nov. represents the 54th member of the genus and the ninth marine congener known from Japan.

Immune-related adverse events in urothelial cancer patients: Adjustment for immortal time bias.

To investigate the association between the onset, severity, and type of immune-related adverse events (irAEs) and the efficacy of pembrolizumab in patients with platinum-pretreated advanced urothelial carcinoma (UC), we retrospectively collected clinical datasets of 755 patients and conducted landmark analysis. Patients who survived for fewer than 3 months were excluded from the evaluation to reduce the immortal time bias. In total, 620 patients were evaluated, of whom 220 patients (35.5%) experienced grade ≥2 irAEs, including 134 patients with grade 2 irAEs and 86 with grade ≥3 irAEs. Propensity score matching extracted 198 patients with and without grade ≥2 irAEs. The onset of grade ≥2 irAEs was associated with longer median progression-free survival (PFS) (8.3 months vs. 4.5 months, p = 0.003) and overall survival (OS) (20.4 months vs. 14.3 months, p = 0.031) and a higher objective response rate (ORR) (44.8% vs. 30.2%, p = 0.004). Patients with grade 2 irAEs had significantly better oncological outcomes (PFS, OS, and ORR) than grade ≤1 and ≥3 irAEs. Patients with grade ≥3 irAEs had worse outcomes than grade 2 irAEs. Endocrine and skin irAEs were related with better survival outcomes, and the rate of severities was lower in these categories. In conclusion, the occurrence of irAEs, particularly low-grade irAEs, was predictive of pembrolizumab efficacy in patients with platinum-pretreated advanced UC.

Clinical and molecular correlates of response to immune checkpoint blockade in urothelial carcinoma with liver metastasis.

Despite recent advancements in immunotherapy, urothelial carcinoma patients with liver metastasis have a poor response to immune checkpoint inhibitors (ICIs) and short survival durations. Here, we investigated the clinical activity and molecular correlates of resistance to ICI in patients with metastatic urothelial carcinoma (mUC), focusing on liver metastasis. In this study, 755 patients with mUC who received pembrolizumab (JUOG cohort), 144 mUC patients who were treated with atezolizumab (IMvigor210 cohort), and 59 mUC patients who had metastatic samples available were enrolled. The presence of liver metastasis was associated with increased peripheral monocytes and a reduction in lymphocytes when compared with other metastatic sites, and a poor prognosis for ICI therapy. The peripheral monocyte-to-lymphocyte ratio was significantly correlated with the CD163+M2-like tumor-associated macrophage (TAM)/CD8+ tumor-infiltrative lymphocyte (TIL) ratio in the primary and metastatic UC lesions. Exploratory molecular analyses indicated that ICI-resistant status, such as decreased tumor mutation burden, low CD8+ TILs and immune checkpoint signatures, and increased M2-like TAM markers, in primary tumors was correlated with the presence of liver metastasis. In metastatic lesions, the CD163+M2-like TAM/CD8+TIL ratio and expression of cancer-associated fibroblasts induced by the TGFß signaling pathway were higher in the liver versus the lung metastatic tumors. This study indicated that tumor-infiltrating lymphocyte and macrophage status in primary and metastatic lesions, which correlate with peripheral monocyte and lymphocyte status, may predict immunotherapy outcomes in UC patients with liver metastasis.

Clinical practice pattern in patients with advanced urothelial cancer who had progressed on pembrolizumab in the pre-enfortumab vedotin era.

OBJECTIVES: Pembrolizumab, an anti-PD-1 monoclonal antibody, revolutionized the treatment for advanced urothelial carcinoma. However, the standard treatment for patients after disease progression with pembrolizumab had not been established until the recent approval of enfortumab vedotin. We analyzed the treatment of these patients in the real world, and the patient background and outcomes. METHODS: We extracted data from 543 patients who experienced progressive disease after pembrolizumab initiation from a Japanese nation-wide cohort of platinum-refractory, metastatic urothelial carcinoma. RESULTS: The median overall survival of the 543 patients was 3.5 months (95% confidence interval 3.0-4.1). Of these, only 20.6% (n = 112) received chemotherapy as a subsequent systemic treatment after progressive disease. The regimen of chemotherapy was very diverse. The median overall survival was 11.9 months (95% confidence interval 9.2-14.7) for patients who received chemotherapy, compared to 2.4 months for those who did not receive chemotherapy (95% confidence interval 2.1-2.9; P < 0.0001). Patients who received subsequent chemotherapy were more likely to have better performance status, neutrophil-to-lymphocyte ratio <3, hemoglobin >11 mg/dL, and history of a single chemotherapeutic regimen at pembrolizumab initiation. CONCLUSIONS: This report highlights the real-world practice of the management after pembrolizumab treatment failure in the pre-enfortumab vedotin era, characterized by infrequent use of subsequent anticancer therapy comprising various regimens, reflecting the lack of a standard treatment. Clinical introduction of enfortumab vedotin is expected to improve treatment outcomes in this setting. The present study will provide important baseline data for evaluating the influence of enfortumab vedotin on clinical practices and outcomes.

Antitumor effect of WEE1 blockade as monotherapy or in combination with cisplatin in urothelial cancer.

Overcoming cisplatin (CDDP) resistance is a major issue in urothelial cancer (UC), in which CDDP-based chemotherapy is the first-line treatment. WEE1, a G2 /M checkpoint kinase, confers chemoresistance in response to genotoxic agents. However, the efficacy of WEE1 blockade in UC has not been reported. MK-1775, a WEE1 inhibitor also known as AZD-1775, blocked proliferation of UC cell lines in a dose-dependent manner irrespective of TP53 status. MK-1775 synergized with CDDP to block proliferation, inducing apoptosis and mitotic catastrophe in TP53-mutant UC cells but not in TP53-WT cells. Knocking down TP53 in TP53-WT cells induced synergism of MK-1775 and CDDP. In UMUC3 cell xenografts and two patient-derived xenograft lines with MDM2 overexpression, in which the p53/cell cycle pathway was inactivated, AZD-1775 combined with CDDP suppressed tumor growth inducing both M-phase entry and apoptosis, whereas AZD-1775 alone was as effective as the combination in RT4 cell xenografts. Drug susceptibility assay using an ex vivo cancer tissue-originated spheroid system showed correlations with the in vivo efficacy of AZD-1775 alone or combined with CDDP. We determined the feasibility of the drug susceptibility assay using spheroids established from UC surgical specimens obtained by transurethral resection. In conclusion, WEE1 is a promising therapeutic target in the treatment of UC, and a highly specific small molecule inhibitor is currently in early phase clinical trials for cancer. Differential antitumor efficacy of WEE1 blockade alone or combined with CDDP could exist according to p53/cell cycle pathway activity, which might be predictable using an ex vivo 3D primary culture system.

Trp53 Mutation in Keratin 5 (Krt5)-Expressing Basal Cells Facilitates the Development of Basal Squamous-Like Invasive Bladder Cancer in the Chemical Carcinogenesis of Mouse Bladder.

The biological processes of urothelial carcinogenesis are not fully understood, particularly regarding the relationship between specific genetic events, cell of origin, and molecular subtypes of subsequent tumors. N-butyl-N-(4-hydroxybutyl)-nitrosamine (BBN)-induced mouse bladder cancer is widely accepted as a useful model that recapitulates the pathway of human bladder tumorigenesis from dysplasia to invasive cancer via carcinoma in situ. However, the long and variable time of tumorigenesis often hinders efficient preclinical or translational research. We hypothesized that Trp53 mutation in specific types of urothelial cells facilitates efficient development of clinically relevant bladder cancer. Using lineage tracing, we showed that Trp53 mutation in Krt5-expressing cells resulted in more efficient tumorigenesis of mouse muscle-invasive bladder cancer (MIBC) with squamous differentiation compared with Trp53 mutation in Upk2-expressing cells, or wild-type or hemizygous Trp53 in the entire urothelium. Mouse MIBC that developed at 24 weeks of BBN treatment showed morphologic and genetic similarities to the basal squamous subtypes of human MIBC, irrespective of pre-induction of Trp53 mutation or whether the cell of origin was Krt5- or Upk2-expressing cells. Our findings suggest that intermediate cells as well as basal cells also can give rise to basal-like MIBC, with pre-induction of Trp53 mutation accelerating MIBC. Thus, in BBN chemical carcinogenesis, pre-induction of Trp53 mutation in basal cells facilitates efficient modeling of the basal squamous subtype of human MIBC.

Synthesis of six-membered carbocyclic ring α,α-disubstituted amino acids and arginine-rich peptides to investigate the effect of ring size on the properties of the peptide.

Cell-penetrating peptides (CPPs) have been attracting attention as tools for intracellular delivery of membrane-impermeant functional molecules. Among the variety of CPPs that have been developed, many are composed of both natural and unnatural amino acids. We previously synthesized α,α-disubstituted α-amino acids (dAAs) containing a five-membered carbocyclic ring in its side chain and revealed the utility of dAAs for the development of novel CPPs. In the present study, we designed a six-membered carbocyclic ring dAA with an amino group on the ring and introduced it into arginine (Arg)-rich peptides to further investigate the value of dAAs for developing CPPs. We also assessed the effects of the size of the dAA carbocyclic ring on cellular uptake of dAA-containing peptides. The stability of the peptide's secondary structure and its membrane permeability were both greater in dAA-containing peptides than in an Arg nonapeptide. However, the number of carbon atoms in the dAA side chain ring had little effect. Nevertheless, these results show the utility of cyclic dAAs in the design of novel CPPs containing unnatural amino acids.

[A Case of Pelvic Unicentric Castleman Disease Treated by Preoperative Transcatheter Arterial Embolization and Tumor Complete Resection with Combined Lower Abdominal and Posterior Approach].

A 22-year-old woman was referred to our hospital for further examination of an incidentally discovered hypervascular pelvic tumor with a maximum diameter of 10 cm. Although Castleman disease was suspected based on the imaging findings and pathologic findings of the needle biopsy, a definitive diagnosis was not made. Preoperative transcatheter arterial embolization was performed to decrease intraoperative bleeding, and tumor resection was performed on the following day. As for posterior approach prior to anterior approach, the patient was placed in a prone position, and the dorsal aspect of tumor was approached through the dissection of gluteal muscles. Then, dilated branches of the internal iliac vein was found on the tumor capsule, which were safely ligated under direct vision with favorable visual field. Then, the patient was placed in a supine position, the tumor was completely resected by anterior approach without transfusion. Histopathological diagnosis was Castleman disease hyaline vascular type. The patient was discharged without complication and has been free from recurrence for 6 months after surgery.

Downregulation of RalGTPase-activating protein promotes invasion of prostatic epithelial cells and progression from intraepithelial neoplasia to cancer during prostate carcinogenesis.

RalGTPase-activating protein (RalGAP) is an important negative regulator of small GTPases RalA/B that mediates various oncogenic signaling pathways in various cancers. Although the Ral pathway has been implicated in prostate cancer (PCa) development and progression, the significance of RalGAP in PCa has been largely unknown. We examined RalGAPα2 expression using immunohistochemistry on two independent tissue microarray sets. Both datasets demonstrated that the expression of RalGAPα2 was significantly downregulated in PCa tissues compared to adjacent benign prostatic epithelia. Silencing of RalGAPα2 by short hairpin RNA enhanced migration and invasion abilities of benign and malignant prostate epithelial cell lines without affecting cell proliferation. Exogenous expression of wild-type RalGAP, but not the GTPase-activating protein activity-deficient mutant of RalGAP, suppressed migration and invasion of multiple PCa cell lines and was phenocopied by pharmacological inhibition of RalA/B. Loss of Ralgapa2 promoted local microscopic invasion of prostatic intraepithelial neoplasia without affecting tumor growth in a Pten-deficient mouse model for prostate tumorigenesis. Our findings demonstrate the functional significance of RalGAP downregulation to promote invasion ability, which is a property necessary for prostate carcinogenesis. Thus, loss of RalGAP function has a distinct role in promoting progression from prostatic intraepithelial neoplasia to invasive adenocarcinoma.

Systematic chemical screening identifies disulfiram as a repurposed drug that enhances sensitivity to cisplatin in bladder cancer: a summary of preclinical studies.

BACKGROUND: Since the standard gemcitabine and cisplatin (GC) chemotherapy for advanced bladder cancer yields limited therapeutic effect due to chemoresistance, it is a clinical challenge to enhance sensitivity to GC. METHODS: We performed high-throughput screening by using a library of known chemicals and repositionable drugs. A total of 2098 compounds were administered alone or with GC to human bladder cancer cells, and chemicals that enhanced GC effects were screened. RESULTS: Disulfiram (DSF), an anti-alcoholism drug, was identified as a candidate showing synergistic effects with cisplatin but not with gemcitabine in multiple cell lines. Co-administration of DSF with GC affected cellular localisation of a cisplatin efflux transporter ATP7A, increased DNA-platinum adducts and promoted apoptosis. Micellar DSF nanoparticles (DSF-NP) that stabilised DSF in vivo, enhanced the inhibitory effect of cisplatin in patient-derived and cell-based xenograft models without severe adverse effects. A drug susceptibility evaluation system by using cancer tissue-originated spheroid culture showed promise in identifying cases who would benefit from DSF with cisplatin. CONCLUSIONS: The present study highlighted the advantage of drug repurposing to enhance the efficacy of anticancer chemotherapy. Repurposing of DSF to a chemotherapy sensitiser may provide additional efficacy with less expense by using an available drug with a well-characterised safety profile.

[A Case of Late Onset Nivolumab-Induced Interstitial Nephritis in a Patient with Metastatic Renal Cell Carcinoma].

A 43-year-old man underwent nephrectomy for right renal cell carcinoma (cT3aN0M1 (PUL), clear cell carcinoma). Thereafter, he was treated with sunitinib for lung metastases as the first-line therapy for three months. Because lung metastases progressed and new bone metastases appeared, nivolumab was started for the second-line treatment. Although the cancer progression was suppressed by multidisciplinary treatment combined with systemic immunotherapy and local radiation therapy, he developed severe acute kidney injury with cortical swelling after eighteen months of nivolumab treatment. A diagnosis of acute interstitial nephritis induced by nivolumab was made based on biopsy findings. Treatment with prednisolone (1.0 mg/kg daily) led to a rapid improvement in renal function. We must consider the possibility of immunerelated adverse events, especially nivolumab-induced acute kidney injury, even after long-term treatment.

[Clinical Effect of Nivolumab on Advanced Renal Cell Carcinoma with Peritoneal Metastasis].

Peritoneal dissemination or metastasis is a relatively rare presentation of renal cell carcinoma. We report four cases of advanced renal cell carcinoma with peritoneal metastases treated with nivolumab. Three cases showed an objective response in the metastatic lesions including peritoneal sites. After nivolumab administration, the computed tomography scan showed a transient enlargement of peritoneal lesions in two cases, which could be considered as pseudoprogression. Temporal changes of neutrophil-tolymphocyte ratio, C-reactive protein, and eosinophil ratio during the clinical course reflected the treatment effect of nivolumab in these patients, indicating that these could be potential biomarkers of the response. To our knowledge, this is the first case series showing therapeutic activity of nivolumab against peritoneal metastases in patients with renal cell carcinoma.

A novel case presenting with an unusual ureteral diverticular lesion similar to adenomyomatous hyperplasia of the gallbladder.

We present the first case of an unusual ureteral diverticular lesion demonstrating similarities to adenomyomatous hyperplasia of the gallbladder. A 68-year-old asymptomatic Japanese man with high prostate-specific antigen levels was clinically evaluated. Left hydronephrosis and benign prostatic hyperplasia were detected. A bilateral retrograde pyelogram revealed that the upper and middle portions of the left ureter exhibited an irregular narrow lumen and some pooling of contrast material, which was compatible with ureteral pseudodiverticulosis. Although no malignant cells were seen on cytology, computed tomography detected a fusiform shaped lesion with a circumferential thick wall including multiple diverticulae. Left nephroureterectomy was performed because malignancy could not be ruled out. Pathology demonstrated that the ureteral lesion showed a localized thick wall consisting of multilocules and/or multicysts and a hyperplastic muscularis propria. The cysts were mostly seen in the muscularis propria or a deeper site. The inner layers of the cysts were lined with normal urothelium, and some cysts opened onto the mucosal surface, indicating that they were derived from invaginated mucosal epithelium. We believe that this lesion may be a novel form of diverticular disorder demonstrating similarities to adenomyomatous hyperplasia of the gallbladder.

Development of a Sol Particle Homogeneous Immunoassay for Measuring Full-Length Selenoprotein P in Human Serum.

BACKGROUND: Selenoprotein P (SeP), a selenium-rich extracellular glycoprotein, is the primary selenoprotein in the plasma. SeP plays an important role in the maintenance of selenium levels in the peripheral tissues. We developed a new sol particle homogeneous immunoassay (SPIA) for measuring full-length SeP (FL-SeP) levels in the human serum. METHODS: We used colloidal gold particles coated with two types of anti-SeP monoclonal antibodies, one recognizing the N-terminal side domain of SeP and the other recognizing the C-terminal side domain. RESULTS: The assay range was 0.2-9 mg/l, and the linearity was excellent. The within-day and between-day coefficients of variation ranged from 0.73% to 2.24% and 0.45% to 1.11%, respectively. Serum samples (n = 200) were examined using the newly developed assay system (employing a Model 7070 Hitachi automatic clinical analyzer) and the conventional enzyme-linked immunosorbent assay. These two methods were compared using the Passing-Bablok regression analysis; the resulting regression equation and correlation coefficient were y = 0.940x + 0.165 and r = 0.954, respectively. CONCLUSIONS: Our new SPIA assay is a fully automated homogeneous immunoassay that can be used in conjunction with various commercial analyzers. The assay was sensitive, precise, and suitable for clinical measurement of the FL-SeP in the human serum.