Pictorial review of multiparametric MRI in bladder urothelial carcinoma with variant histology: pearls and pitfalls.

Bladder cancer (BC), predominantly comprising urothelial carcinomas (UCs), ranks as the tenth most common cancer worldwide. UCs with variant histology (variant UC), including squamous differentiation, glandular differentiation, plasmacytoid variant, micropapillary variant, sarcomatoid variant, and nested variant, accounting for 5-10% of cases, exhibit more aggressive and advanced tumor characteristics compared to pure UC. The Vesical Imaging-Reporting and Data System (VI-RADS), established in 2018, provides guidelines for the preoperative evaluation of muscle-invasive bladder cancer (MIBC) using multiparametric magnetic resonance imaging (mpMRI). This technique integrates T2-weighted imaging (T2WI), dynamic contrast-enhanced (DCE)-MRI, and diffusion-weighted imaging (DWI) to distinguish MIBC from non-muscle-invasive bladder cancer (NMIBC). VI-RADS has demonstrated high diagnostic performance in differentiating these two categories for pure UC. However, its accuracy in detecting muscle invasion in variant UCs is currently under investigation. These variant UCs are associated with a higher likelihood of disease recurrence and require precise preoperative assessment and immediate surgical intervention. This review highlights the potential value of mpMRI for different variant UCs and explores the clinical implications and prospects of VI-RADS in managing these patients, emphasizing the need for careful interpretation of mpMRI examinations including DCE-MRI, particularly given the heterogeneity and aggressive nature of variant UCs. Additionally, the review addresses the fundamental MRI reading procedures, discusses potential causes of diagnostic errors, and considers future directions in the use of artificial intelligence and radiomics to further optimize the bladder MRI protocol.

Concurrent intestinal plasmablastic lymphoma and diffuse large B-cell lymphoma with a clonal relationship: a case report and literature review.

Herein, we report a case of plasmablastic lymphoma (PBL) and diffuse large B-cell lymphoma (DLBCL) that occurred concurrently in the large intestine. An 84-year-old female presented with a palpable rectal tumor and ileocecal tumor observed on imaging analyses. Endoscopic biopsy of both lesions revealed lymphomatous round cells. Hartmann's operation and ileocecal resection were performed for regional control. The ileocecal lesion consisted of a proliferation of CD20/CD79a-positive lymphoid cells, indicative of DLBCL. In contrast, the rectal tumor showed proliferation of atypical cells with pleomorphic nuclei and abundant amphophilic cytoplasm, with immunohistochemical findings of CD38/CD79a/MUM1/MYC (+) and CD20/CD3/CD138/PAX5 (-). Tumor cells were positive for Epstein-Barr virus- encoded RNA based on in situ hybridization and MYC rearrangement in fluorescence in situ hybridization analysis. These findings indicated the rectal tumor was most likely a PBL. Sequencing analysis for immunoglobulin heavy variable genes indicated a common B-cell origin of the two sets of lymphoma cells. This case report and literature review provide new insights into PBL tumorigenesis.

High frequency of concomitant squamous metaplasia in bulbar urethral stricture and its association with reconstructive delay and urethral rest.

PURPOSE: To determine the prevalence of concomitant squamous metaplasia (SM), the initial histological change from normal urethra to urethral stricture, in bulbar urethral strictures and to investigate the associated clinical factors. METHODS: A retrospective review was conducted on 165 male patients with bulbar urethral strictures who underwent excision and primary anastomosis (EPA) between 2010 and 2020, for whom complete clinical data and excised urethral specimens were available. An experienced pathologist histologically evaluated concomitant SM in paraffin sections of the proximal end of the excised urethra blinded to the clinical data. Disease duration was calculated as the period from the initial diagnosis of urethral stricture to the date of EPA. The association between concomitant SM and clinical background was investigated. RESULTS: SM was identified in 86 (52.1%) patients. The median disease duration in patients with SM (38 months) was significantly longer than that in patients without SM (9 months, p < 0.0001). In multivariate analysis, the longer disease duration, non-traumatic stricture etiology, and failure to maintain urethral rest with urinary diversion via a suprapubic tube for more than 90 days were independent factors predicting concomitant SM. No significant difference was observed in success rates of EPA between patients with SM (93.2%) and those without SM (97.5%, p = 0.18). CONCLUSIONS: Reconstructive urologists need to be aware that concomitant SM is frequent in patients with bulbar urethral stricture, especially in those with long disease duration and those who were voiding volitionally during the period of urethral rest.

Idiopathic myointimal hyperplasia of mesenteric veins: radiological evaluation using CT angiography.

A 44-year-old man presented with a chief complaint of constipation. Initial contrast-enhanced CT showed extensive bowel wall thickening, mainly in the left colon, with a thin cord-like inferior mesenteric vein (IMV), in contrast to ectatic mesenteric venous branches, suggesting bowel ischaemia owing to venous stasis. One month later, at the time of symptom exacerbation, CT angiography showed a cord-like IMV and ectatic mesenteric venous branches with early enhancement, suggesting the presence of an arteriovenous fistula (AVF). Owing to the progression of bowel ischaemia and necrosis with peritonitis, emergency surgery was performed. Surgical specimens showed focal myointimal hyperplasia of the proximal mesenteric veins in both ischaemic and non-ischaemic lesions of the resected colon, thus leading to the diagnosis of idiopathic myointimal hyperplasia of mesenteric veins (IMHMV) when combined with the clinical and imaging findings. IMHMV is a bowel ischaemic disease caused by non-thrombotic venous obstruction that requires bowel resection and has been suggested to be associated with AVF. Cord-like IMV and AVF in the mesentery are important CT findings that characterize IMHMV. CT angiography is useful in diagnosing IMHMV.

A case of low-grade endometrial stromal sarcoma presented as an intramyometrial mass mimicking uterine leiomyoma on MRI.

A low-grade endometrial stromal sarcoma (ESS) has a pattern of presenting as an intramyometrial mass and is often misdiagnosed as cellular leiomyoma or degenerative uterine leiomyoma. A low-grade ESS is a malignant tumour that requires total hysterectomy with bilateral salpingo-oophorectomy; while a leiomyoma is a benign tumour and could be acceptable for enucleation. As the treatment strategies differ between a low-grade ESS and leiomyoma, radiologists should be familiar with the characteristic MRI findings of a low-grade ESS. A 51-year-old woman with abnormal uterine bleeding had been observed for 2 years at a previous hospital for a uterine leiomyoma based on MRI findings. A contrast-enhanced MRI demonstrated an intramyometrial mass composed of three components with the hypointense rim on T2-weighted images (T2WI): the first component was a homogeneous solid structure with mild hyperintensity on T2WI with a low apparent diffusion coefficient value; the second component was cystic; the third component was a structure of low signal intensity on T2WI similar to the muscle. Although a degenerative uterine leiomyoma was a differential diagnosis, these MRI findings were suggestive of a low-grade ESS. A total abdominal hysterectomy, bilateral salpingo-oophorectomy, pelvic lymphadenectomy, and partial omentectomy were performed. The pathological diagnosis was a low-grade ESS. In a low-grade ESS, there are three major patterns of MRI findings: one of these patterns is the less popular but clinically important intramyometrial mass pattern, which can be misdiagnosed as a leiomyoma, and this case conformed to this pattern.

Histological parameters and stromal desmoplastic status affecting accurate diagnosis of extraprostatic extension of prostate cancer using multi-parametric magnetic resonance imaging.

OBJECTIVE: To investigate the clinicopathological factors affecting discrepancies between multi-parametric magnetic resonance imaging (mpMRI) and histopathological evaluation for diagnosis of extraprostatic extension (EPE) of prostate cancer. METHODS: One hundred-and-three lesions from 96 cases with suspected EPE on preoperative mpMRI, of which 60 and 43 showed bulging and frank capsular breach, respectively, were grouped according to pathological (p)EPE in radical prostatectomy specimens. Additionally, clinicopathological/immunohistochemical findings for periostin reflecting a desmoplastic stromal reaction were compared between these groups. RESULTS: pEPE was detected in 49 (48%) of the 103 lesions. Of these, 25 (42%) showed bulging and 24 (56%) showed frank capsular breach on MRI. In the total cohort, the absence of pEPE was significantly associated with a lower Gleason Grade Group (GG) (p < 0.0001), anterior location (p = 0.003), absence of intraductal carcinoma of the prostate (IDC-P) (p = 0.026), and high stromal periostin expression (p < 0.0001). These trends were preserved in subgroups defined by MRI findings, except for anterior location/IDC-P in the bulging subgroup. CONCLUSIONS: GG, anterior location, and periostin expression may cause mpMRI-pathological discrepancies regarding EPE. Periostin expression was a significant pEPE-negative factor in all subgroup analyses. Our results indicate that patients with suspected EPE on MRI, regardless of their pEPE results, should be followed as carefully as those with definite pEPE.

Implementation of The Paris System for Reporting Urine Cytology improves diagnostic accuracy of selective upper urinary tract cytology.

BACKGROUND: The Paris System for Reporting Urine Cytology (TPS) recommends diagnostic criteria for urinary tract cytology, focusing primarily on the detection of high-grade urothelial carcinoma (HGUC) in the lower urinary tract. The second edition of TPS (TPS 2.0), published in 2022, extends these recommendations to the upper urinary tract (UUT); however, there is a lack of comprehensive data on this subject. METHODS: In total, 223 consecutive UUT cytology specimens from 137 patients were retrieved and reclassified according to TPS 2.0 criteria and were compared with the original diagnosis based on the conventional system (CS). Histologic follow-up within a 3-month period was conducted for 43 patients. RESULTS: Histologic follow-up revealed 30 HGUCs, five low-grade urothelial carcinomas (LGUCs), and eight nonneoplastic fibrotic tissues. The risk of high-grade malignancy for each TPS diagnostic category was 16.7% for nondiagnostic/unsatisfactory, 2.3% for negative for HGUC (NHGUC), 42.1% for atypical urothelial cells, 50.0% for suspicious for HGUC (SHGUC), and 81.8% for HGUC. In all five cases of histologically diagnosed LGUC, the cytologic diagnosis was NHGUC. When SHGUC/HGUC was considered positive, the diagnostic accuracy of TPS had 63% sensitivity, 95% specificity, a 90% negative predictive value, and a 79% positive predictive value, which were better than those of CS. In addition, the TPS indices did not differ significantly between the specimens obtained before and after the application of contrast reagents. CONCLUSIONS: TPS implementation improved the accuracy of UUT cytology in predicting histologic HGUC, which was unaffected by the application of contrast reagents. These data indicate the usefulness of TPS for UUT cytology in routine clinical settings.

Copy number gain of ACTN4 is associated with poor prognosis in patients with upper urinary tract urothelial carcinoma.

α-Actinin4 (ACTN4), an isoform of non-muscular α-actinin, is involved in enhancing cell motility and promoting cancer infiltration and metastasis in various cancers. However, information remains limited regarding the pathological significance of ACTN4 expression in upper urinary tract urothelial carcinomas (UUTUCs). We obtained tumor samples from 168 consecutive patients with newly diagnosed UUTUCs (92 with renal pelvic cancers and 76 with ureteral cancers), who were treated with nephroureterectomy or partial ureterectomy, and analyzed the expression of the ACTN4 protein and the amplification of ACTN4 using immunohistochemistry and fluorescence in situ hybridization (FISH), respectively. The median follow-up duration was 65 months. Among 168 cases, 49 (29%) showed ACTN4 protein overexpression and 25 (15%) showed copy number gain (≥4 copies per cell) of ACTN4. The copy number gain of ACTN4 detected using FISH significantly correlated with ACTN4 protein overexpression and several adverse clinicopathological factors, including higher pathological T stage, lymphovascular invasion, lymph node metastasis, positive surgical margin, concomitant subtype histology, and non-papillary gross finding. Cox univariate regression analyses revealed that both copy number gain of ACTN4 and ACTN4 protein overexpression were significant risk factors for extraurothelial recurrence and death (each p < 0.0001), but multivariate analysis revealed that only copy number gain of ACTN4 was an independent risk factor for extraurothelial recurrence and death (p = 0.038 and 0.027, hazard ratio = 2.16 and 2.17, respectively). This is the first study demonstrating the aberrant expression status of ACTN4 in UUTUC and indicating its putative usefulness as a prognostic indicator in patients with UUTUC.

Polypoid-Type Adenomyomatous Lesion of the Cystic Duct: Report of a Case and Review of Literature.

Adenomyomatous hyperplasia, a common non-neoplastic lesion in the gallbladder, is rarely identified in the extrahepatic bile duct. Typically, these lesions appear as a nodule or mural thickening/elevation. However, in exceptional circumstances, pedunculated/polypoid adenomyomatous lesion occurs in the biliary tract; two cases in the gallbladder and only one case in the common bile duct have been reported. Despite their benign nature, adenomyomatous lesions, especially those with a polypoid appearance, are clinically difficult to exclude a possibility of malignant neoplasms. We describe a case of polypoid-type adenomyomatous lesion of the cystic duct in a 72-year-old man, which was considered as a cystic duct neoplasm preoperatively. Gross examination of the resected specimen revealed that the 9 mm-sized cystic duct polyp. Histologically, the polypoid lesion consisted of glands without atypia, fibrous stroma, smooth muscle bundles, and accompanying stromal inflammation, leading to the diagnosis of benign adenomyomatous lesion. The lesion might be considered as adenomyomatous hyperplasia arising in the valve of Heister, while true nature of the lesion is uncertain. Recognition and accumulating for this rare disease will contribute to better clinical management in the future.

Myofibroblast-dominant proliferation associated with severe fibrosis in bulbar urethral strictures.

OBJECTIVES: Myofibroblast-dominant proliferation (relative to fibroblast proliferation) is the key process in urethral fibrosis, but its association with clinical features is not understood. We conducted a histological analysis of urethral strictures and examined the association between myofibroblast proliferation and stricture characteristics. METHODS: Formalin-fixed, paraffin-embedded urethral sections sliced axially from 175 male patients with bulbar urethral strictures were retrospectively analyzed. All patients underwent excision and primary anastomosis between September 2008 and January 2021 by a surgeon (AH). Masson's trichrome stain was used to estimate the area of fibrosis. Corresponding unstained slides with the largest area of fibrosis were selected and double-immunostained with anti-smooth muscle actin (SMA) and anti-TE-7 mouse monoclonal antibodies for the assessment of myofibroblasts and fibroblasts, respectively. The ratio of the number of SMA-positive cells to the number of TE-7-positive cells (SMA/TE-7 ratio) was calculated. RESULTS: The area of fibrosis in strictures due to perineal trauma (n = 85, median 108.9 mm2 ) was significantly larger than that in non-traumatic strictures (n = 90, median 42.9 mm2 , p < 0.0001). The area of fibrosis positively correlated with SMA expression (r = 0.35, p < 0.0001) and the SMA/TE-7 ratio (r = 0.36, p < 0.0001), but not with TE-7 expression (r = -0.01, p = 0.75). In a multivariate linear regression model, traumatic etiology (standard coefficient 0.37, t value 3.9, p < 0.0001) and increased SMA expression (standard coefficient 0.17, t value 2.1, p = 0.03) were the predictors of wide fibrosis area. CONCLUSIONS: Myofibroblast-dominant proliferation may contribute to the pathogenesis of severe urethral fibrosis.

Prognostic impact of stromal periostin expression in upper urinary tract urothelial carcinoma.

BACKGROUND: Periostin is an extracellular matrix protein that has been known to be implicated in fibrillogenesis and cell migration, including cancer metastasis. Periostin overexpression in cancer cells and/or intervening stroma is usually related to tumor progression and poor patient outcomes in various human cancers; however, its role in urothelial carcinoma, especially upper urinary tract urothelial carcinomas (UTUCs), remains inconclusive. METHODS: Samples from 126 consecutive cases of invasive UTUC (69 renal pelvic cancers and 57 ureteral cancers) were histologically reviewed and analyzed for periostin expression using immunohistochemistry. The intensities of immunoreactivity and the fraction of positive cancer cells and stroma (i.e., epithelial and stromal expression, respectively) were classified into four categories each (intensity, 0-3; fraction, 0-25% = 1; 26-50% = 2; 51-75% = 3; and > 75% = 4). The overall score was determined by multiplying both scores, and overall scores ≥ 6 were considered to indicate high periostin expression. RESULTS: Among 126 UTUCs, 55 (44%; 27 renal pelvic and 28 ureteral cancers) showed high stromal periostin expression. None of the cases were considered to have high epithelial periostin expression. High stromal periostin expression was associated with non-papillary gross findings, higher pathological T category, lymphovascular invasion, concomitant carcinoma in situ, subtype histology, lymph node metastasis, positive surgical margins, high tumor budding, and high tumor-associated immune cell status. Multivariate analysis revealed that high stromal periostin expression was an independent predictor of overall survival (p = 0.00072, hazard ratio = 3.62), and lymphovascular invasion and high stromal periostin expression were independent predictors of cancer-specific survival (p = 0.032 and 0.020, hazard ratio = 2.61 and 3.07, respectively). CONCLUSIONS: Stromal periostin expression was often observed in invasive UTUCs with adverse clinicopathological factors and may be a useful predictor of patient outcomes.

Clinically undetected plasmacytoid urothelial carcinoma of the urinary bladder with non-mass-forming metastases in multiple organs: an autopsy case.

This case report outlines a clinically undetected urinary bladder plasmacytoid urothelial carcinoma (PUC) with multiple metastases detected at autopsy. An 89-year-old man presented with edema in the lower limbs. Pleural fluid cytology revealed discohesive carcinomatous cells, although imaging studies failed to identify the primary site of tumor. The patient died of respiratory failure. Autopsy disclosed a prostate tumor and diffusely thickened urinary bladder and rectum without distinct tumorous lesions. Histologically, the tumor consisted of acinar-type prostate adenocarcinoma with no signs of metastasis. Additionally, small, plasmacytoid tumor cells were observed in the urinary bladder/rectum as isolated or small clustering fashions. These metastasized to the lungs, intestine, generalized lymph nodes in a non-mass-forming manner. Combined with immunohistochemical studies, these tumor cells were diagnosed PUC derived from the urinary bladder. Both clinicians and pathologists should recognize PUC as an aggressive histological variant, which can represent a rapid systemic progression without mass-forming lesions.

Risk assessment of femoral pathological fracture in prostate cancer patients by computed tomography analysis.

INTRODUCTION: Prostate cancer often forms osteoblastic lesions that appear as a high-dense shadow upon X-ray. Although the lesions may seem to increase bone strength, pathological fracture occurs in one in four patients with prostate cancer. The aim of this study is to elucidate the factors that may increase the risk of pathological fracture in patients with prostate cancer metastases in the proximal femur by analyzing computed tomography data. MATERIALS AND METHODS: Computed tomography data of the femur of 62 prostate cancer patients were retrospectively analyzed. The patients were divided into three groups based on the presence or absence of femoral metastatic lesions and pathological fracture. Surgical specimens of the proximal femur collected from patients who had a pathological fracture were histologically analyzed. RESULTS: Bone density in the marrow area was increased in all cases with metastases compared with those with no metastases. Contrarily, the cortical bone density at the medial trochanter region was significantly lower in patients who had pathological fractures in the proximal femur than those who did not. Accordingly, histological analysis of the surgical specimens revealed that the affected cortical bone was osteopenic without any apparent new bone formation. CONCLUSION: These results indicate that prostate cancer is less effective in inducing bone formation in the cortex than in the marrow and that the decrease in the cortical bone density at the medial trochanter region leads to an increased risk of pathological fracture. Therefore, a previously undocumented risk factor for pathological fracture in prostate cancer patients is presented.

Intraepithelial lymphocytes are indicators of better prognosis in surgically resected endometrioid-type endometrial carcinomas at early and advanced stages.

BACKGROUND: Tumor-infiltrating lymphocytes (TILs) and tumor-associated macrophages (TAMs) may be useful prognostic indicators in endometrial cancer. However, standardized assessment methods and the prognostic roles of these cells in different stage groups are unclear. METHODS: Formalin-fixed paraffin-embedded tissue samples of 107 endometrioid-type endometrial carcinomas (EECs) comprising 60 stage IB and 47 stage IIIC or IVB cases were evaluated. CD3+ TILs, CD8+ TILs, CD68+ TAMs, and CD163+ TAMs were detected by immunohistochemistry, and their densities were evaluated by semiquantitative and quantitative methods. TILs within tumor epithelial cell nests (E-TILs) and those within the stroma at the invasive front (S-TILs) were evaluated separately for CD3+ and CD8+ cells. The "TIL score" was defined as the sum of semiquantitative scores of CD3+ E-TILs, CD3+ S-TILs, CD8+ E-TILs, and CD8+ S-TILs. For TAMs, the area of CD68+ and CD163+ cells in the invasive margin were semiquantitatively and quantitatively evaluated. Clinicopathological and prognostic implications of TILs and TAMs in stage IB and IIIC/IVB EECs were examined by Cox univariate and multivariate analyses. RESULTS: By Cox univariate analyses, semiquantitatively low CD3+ E-TILs, low CD8+ E-TILs, and low "TIL score" were significantly correlated with worse prognosis in stage IB patients (P = 0.011, 0.040, and 0.039, respectively). Likewise, low CD3+ E-TILs and low CD8+ E-TILs, by both semiquantitative (P = 0.011 and 0.0051) and quantitative evaluations (P < 0.0001, and P = 0.0015) and low "TIL score" (P = 0.020) were significantly correlated with worse prognosis in stage IIIC/IVB patients. By Cox multivariate analyses, semiquantitatively low CD3+ E-TILs and low CD8+ E-TILs, low "TIL score", and quantitatively low CD3+ E-TILs and low CD8+ E-TILs were independent worse prognostic factors in stage IIIC/IVB (P = 0.0011, 0.0053, 0.012, < 0.0001, and < 0.0001, respectively). CD68+ or CD163+ TAMs were not correlated with prognosis in any patients. CONCLUSIONS: Both semiquantitatively and quantitatively low E-TILs, are correlated with worse prognosis in both early and advanced stage patients with EECs. In particular, CD3+ E-TILs and CD8+ E-TILs are potentially useful prognostic markers in patients with EEC regardless of the stage.

Magnetic resonance imaging findings of pure prostatic ductal adenocarcinomas: a case series.

PURPOSE: This study aimed to investigate the characteristics of magnetic resonance imaging (MRI) findings in pure prostatic ductal adenocarcinoma. METHODS: From January 2009 to February 2020, seven patients who were diagnosed with pure prostatic ductal adenocarcinoma and had a referable preoperative MRI scan were included in the study. We evaluated the following MRI findings for each tumor: size, location, presence of multi-cystic component, and apparent diffusion coefficient (ADC) value. RESULTS: The median maximum diameter of the tumors was 22 mm (range 19-70 mm). Regarding transverse distribution, five tumors were located in the periurethral area and two were located peripherally apart from the urethra. Two of the seven tumors had cystic components. The median ADC value of the tumors was 0.754 × 10-3 mm2/s (range 0.570-0.963 × 10-3 mm2/s). Based on the transverse distribution and components of the tumors on MRI, ductal adenocarcinomas were classified into three types: type I as a non-cystic tumor located peripherally apart from the urethra (29%, two cases); type II as a non-cystic tumor located in the periurethral area (43%, three cases); and type III as a tumor with a multi-cystic component (29%, two cases). CONCLUSION: The non-cystic mass with periurethral distribution (type II) and multi-cystic mass (type III) may be characteristic features that differentiate pure ductal adenocarcinoma from ordinary acinar adenocarcinoma on MRI.

Ability of photocurable gelatin to prevent stricture recurrence after urethral dilation in rabbits.

OBJECTIVES: To evaluate the ability of photocurable gelatin to prevent stricture recurrence after urethral dilation in a rabbit urethral stricture model. METHODS: We created urethral strictures in the bulbar urethras of 10 male Japanese white rabbits using electrocoagulation. After 1 month, the rabbits were randomly divided into Group A (n = 5; urethral stricture dilation and the local application of photocurable gelatin using a ruthenium photoinitiator and irradiation with a light-emitting diode light [λ = 455 nm, 50 mW/cm2 ] for 1 min) and Group B (n = 5; dilation only). Urethral stricture status was evaluated 1-2 months later by retrograde urethrography and urethroscopy. The lumen ratio (urethral width at the stricture site to the normal urethral width on retrograde urethrography) was calculated. Urethral patency was considered to be improved when the urethral lumen could accommodate a 10-Fr urethroscope without resistance. Urethral specimens were harvested for histopathological examination. RESULTS: The mean lumen ratio did not differ significantly between Groups A and B before dilation (25.8% vs 23.4%; P = 0.40), but differed significantly after dilation (65.5% vs 27.3%, respectively; P = 0.03). Urethral patency improved in all rabbits in Group A (100%) versus one rabbit in Group B (20%; P = 0.02). The mean circumference of the regenerated urethral epithelium at the stricture site was larger in Group A than in Group B (14 mm vs 6.6 mm; P = 0.06). CONCLUSIONS: Photocurable gelatin can reduce urethral stricture recurrence after dilation in a rabbit model.

Chronic lymphocytic leukemia and concurrent seminoma in the same testis.

A 59-year-old man presented with a painless testicular mass and underwent a radical orchiectomy. The resected specimen showed a 5-cm-sized, white-yellow and homogenous solid mass in the testicular parenchyma. Histologically, the central part of the tumor exhibited typical features of seminoma. The peripheral part of the tumor exhibited diffuse infiltration of small, monotonous lymphoid cells involving the tunica albuginea. The monotonous lymphoid cells were immunoreactive for CD20, CD79a, CD5, and CD23, and negative for CD3, CD10, and cyclin D1. Kappa light chain restriction was detected on flow cytometry using the resected specimen. Considering the circulating lymphoid cell count of >5.0×103/µL, we diagnosed the peripheral component of the tumor as an infiltration of chronic lymphocytic leukemia. This extremely rare combination of seminoma and lymphoid neoplasm should be considered in the differential diagnosis of classic seminoma with extensive lymphoid reaction in tumors arising in elderly patients.

Ascorbic acid-2 glucoside mitigates intestinal damage during pelvic radiotherapy in a rat bladder tumor model.

PURPOSE: Ascorbic acid is a strong antioxidant and has potent radioprotective effects on radiation injuries. Ascorbic acid 2-glucoside (AA2G) is a stabilized derivative of ascorbic acid and rapidly hydrolyzed into ascorbic acid and glucose. Since there is the possibility that AA2G treatment interferes with the antitumor activity of radiotherapy, we investigated the effect of AA2G treatment during radiotherapy on acute radiation enteritis and antitumor activity of radiotherapy in rats. MATERIALS AND METHODS: AY-27 rat bladder tumor cells were used to induce bladder tumors in rats. Two weeks after inoculation rats received fractionated pelvic radiotherapy in eight fractions for 4 weeks totaling 40 Gy. During radiotherapy, one group of rats received per os AA2G (ascorbic acid: 250 mg/kg/day) and its bolus engulfment (ascorbic acid: 250 mg/kg) 8 h before each X-irradiation fraction. Seven days after the last X-irradiation, we studied histology, DNA double strand break (DSB) damage (by 53BP1 foci staining), and the M1/M2 macrophage response by immunohistochemistry of paraffin-fixed bladder and intestinal tissues. RESULTS: AA2G treatment reduced the intestinal damage (shortening of villi) but did not reduce antitumor effectiveness of radiotherapy against bladder tumors. Like the controls, AA2G-treated rats showed no residual tumor lesions in the bladder after X-irradiation. Both AA2G-treated and control groups showed similar persistent DSB damage (53BP1 foci) both in bladders and ilea seven days after radiotherapy. Radiotherapy tended to reduce CD163+ M2 macrophages, which are considered as an anti-inflammatory subtype favoring tissue repair, in the bladders. X-irradiation also reduced the occurrence of M2 macrophages in the ilea. AA2G treatment significantly increased CD163+/CD68+ macrophage ratio in the ilea of rats after pelvic irradiation in comparison to the sham irradiated control rats. AA2G treatment increased, albeit not significantly, the CD163+/CD68+ macrophage ratio in the irradiated bladders relative to the control irradiated rats. On the other hand, bladders and ilea of the irradiated rats with and without AA2G treatment showed similar frequencies of CD68+ macrophages. CONCLUSIONS: AA2G treatment mitigated radiation-induced intestinal damage without reducing antitumor activity after fractionated pelvic radiotherapy against bladder tumors in rats. The beneficial effect of AA2G treatment seems to promote a restoration of the M2 answer as well as tissue remodeling and wound healing. Similar residual DNA damage in bladders and ilea seven days post-irradiation is consistent with tumor control in both groups.

MRI-detectability and histological factors of prostate cancer including intraductal carcinoma and cribriform pattern.

BACKGROUND: Histopathological characteristics affecting the detectability of clinically significant prostate cancer (csPCa) on magnetic resonance imaging (MRI) remain unclear. This study aimed to compare the histopathology between MRI-detectable and MRI-undetectable cancers, emphasizing intraductal carcinoma of the prostate (IDC-P) and predominant Gleason pattern 4 subtype. METHODS: This single-center retrospective study enrolled 153 consecutive patients with 191 lesions who underwent preoperative multiparametric MRI and subsequent radical prostatectomy. MRI/histopathological findings and area fractions of histological components (cancer cells, stroma, and luminal spaces) of MRI-detectable and MRI-undetectable cancers were compared. Data were analyzed using Fisher's exact, independent t, or Mann-Whitney U tests. RESULTS: Overall, 148 (77%) and 43 (23%) cancers were MRI-detectable and MRI-undetectable, respectively. MRI-detectable cancers were significantly larger than MRI-undetectable cancers (p = 0.03). The percentage of lesions in Grade Group 3 or higher was significantly higher among MRI-detectable cancers than among MRI-undetectable cancers (p = 0.02). MRI detectability of csPCa was associated with increases in relative area fractions of cancer cells (p < 0.001) and decreases in those of stroma (p < 0.001) and luminal spaces (p < 0.001) in prostate cancer (PCa) than the percentage of Gleason pattern 4 (p = 0.09). The percentage of lesions containing IDC-P was similar for MRI-detectable and MRI-undetectable cancers (40% vs. 33%; p = 0.48). The distribution of cribriform gland subtypes was not significantly different between MRI-detectable and MRI-undetectable Gleason pattern 4 subtype cancers (p > 0.99). Contrarily, the ratio of fused gland subtype was significantly higher in MRI-detectable than in MRI-undetectable cancers (p = 0.03). Furthermore, the ratio of poorly-formed gland subtype was significantly higher in MRI-undetectable than in MRI-detectable cancers (p = 0.01). CONCLUSIONS: MRI detectability of csPCa is strongly associated with the relative area fractions of cancer cells, stroma, and luminal spaces in PCa rather than conventional histopathological parameters. Neither the presence nor the percentage of IDC-P affected MRI detectability.