A Machine Learning Model to Predict the Histology of Retroperitoneal Lymph Node Dissection Specimens

BACKGROUND/AIM

While post-chemotherapy retroperitoneal lymph node dissection (PC-RPLND) benefits patients with teratoma or viable germ cell tumors (GCT), it becomes overtreatment if necrosis is detected in PC-RPLND specimens. Serum microRNA-371a-3p correctly predicts residual viable GCT with 100% sensitivity; however, prediction of residual teratoma in PC-RPLND specimens using current modalities remains difficult. Therefore, we developed a machine learning model using CT imaging and clinical variables to predict the presence of residual teratoma in PC-RPLND specimens.

PATIENTS AND METHODS

This study included 58 patients who underwent PC-RPLND between 2005 and 2019 at the University of Tsukuba Hospital. On CT imaging, 155 lymph nodes were identified as regions of interest (ROIs). The ResNet50 algorithm and/or Support Vector Machine (SVM) classification were applied and a nested, 3-fold cross-validation protocol was used to determine classifier accuracy.

RESULTS

PC-RPLND specimen analysis revealed 35 patients with necrosis and 23 patients with residual teratoma, while histology of 155 total ROIs showed necrosis in 84 ROIs and teratoma in 71 ROIs. The ResNet50 algorithm, using CT imaging, achieved a diagnostic accuracy of 80.0%, corresponding to a sensitivity of 67.3%, a specificity of 90.5%, and an AUC of 0.84, whereas SVM classification using clinical variables achieved a diagnostic accuracy of 74.8%, corresponding to a sensitivity of 59.0%, a specificity of 88.1%, and an AUC of 0.84.

CONCLUSION

Our machine learning models reliably distinguish between necrosis and residual teratoma in clinical PC-RPLND specimens.

Objective Evaluation of Gaze Location Patterns Using Eye Tracking During Cystoscopy and Artificial Intelligence-Assisted Lesion Detection

Background: The diagnostic accuracy of cystoscopy varies according to the knowledge and experience of the performing physician. In this study, we evaluated the difference in cystoscopic gaze location patterns between medical students and urologists and assessed the differences in their eye movements when simultaneously observing conventional cystoscopic images and images with lesions detected by artificial intelligence (AI). Methodology: Eye-tracking measurements were performed, and observation patterns of participants (24 medical students and 10 urologists) viewing images from routine cystoscopic videos were analyzed. The cystoscopic video was captured preoperatively in a case of initial-onset noninvasive bladder cancer with three low-lying papillary tumors in the posterior, anterior, and neck areas (urothelial carcinoma, high grade, and pTa). The viewpoint coordinates and stop times during observation were obtained using a noncontact type of gaze tracking and gaze measurement system for screen-based gaze tracking. In addition, observation patterns of medical students and urologists during parallel observation of conventional cystoscopic videos and AI-assisted lesion detection videos were compared. Results: Compared with medical students, urologists exhibited a significantly higher degree of stationary gaze entropy when viewing cystoscopic images (p < 0.05), suggesting that urologists with expertise in identifying lesions efficiently observed a broader range of bladder mucosal surfaces on the screen, presumably with the conscious intent of identifying pathologic changes. When the participants observed conventional and AI-assisted lesion detection images side by side, contrary to urologists, medical students showed a higher proportion of attention directed toward AI-detected lesion images. Conclusion: Eye-tracking measurements during cystoscopic image assessment revealed that experienced specialists efficiently observed a wide range of video screens during cystoscopy. In addition, this study revealed how lesion images detected by AI are viewed. Observation patterns of observers' gaze may have implications for assessing and improving proficiency and serving educational purposes. To the best of our knowledge, this is the first study to utilize eye tracking in cystoscopy. University of Tsukuba Hospital, clinical research reference number R02-122.

Glycoprotein nonmetastatic melanoma protein B impacts the malignant potential of bladder cancer cells through its hem-immunoreceptor tyrosine-based activation motif

Bladder cancer is one of the most common cancers among men worldwide. Although multiple genomic mutations and epigenetic alterations have been identified, an efficacious molecularly targeted therapy has yet to be established. Therefore, a novel approach is anticipated. Glycoprotein nonmetastatic melanoma protein B (GPNMB) is a type I transmembrane glycoprotein that is highly expressed in various cancers. In this study, we evaluated bladder cancer patient samples and found that GPNMB protein abundance is associated with high-grade tumors, and both univariate and multivariate analyses showed that GPNMB is a prognostic factor. Furthermore, the prognosis of patients with high GPNMB levels was significantly poorer in those with nonmuscle invasive bladder cancer (NMIBC) than in those with muscle invasive bladder cancer (MIBC). We then demonstrated that knockdown of GPNMB in MIBC cell lines with high GPNMB inhibits cellular migration and invasion, whereas overexpression of GPNMB further enhances cellular migration and invasion in MIBC cell lines with originally low GPNMB. Therefore, we propose that GPNMB is one of multiple driver molecules in the acquisition of cellular migratory and invasive potential in bladder cancers. Moreover, we revealed that the tyrosine residue in the hemi-immunoreceptor tyrosine-based activation motif (hemITAM) is required for GPNMB-induced cellular motility.

Patient characteristics correlate with diagnostic performance of photodynamic diagnostic assisted transurethral resection of bladder tumors: A retrospective, single-center study

BACKGROUND

Identification of patient subclasses that correlate with the diagnostic performance of photodynamic diagnostic (PDD)-assisted transurethral resection of bladder tumors (TURBT) may improve outcomes.

METHODS

Data were extracted from patients that underwent PDD-assisted TURBT at the University of Tsukuba Hospital between 2018 and 2023. Sensitivity and specificity were evaluated based on PDD findings (excluding WL findings) and pathology results. Cluster analysis using uniform manifold approximation and projection and k-means methods was performed, focusing on patients with malignant lesions.

RESULTS

A total of 267 patients and 2082 specimens were extracted. Sensitivity was lowest with regard to BCG treatment (53.7 %), followed by flat lesions (57.2 %), urine cytology class ≥ III (62.9 %), and recurrent tumors (64.5 %). In the cluster analysis of 231 patients with malignant lesions, two showed lower sensitivity: Cluster 3 (62.4 %), consisting of patients with recurrent tumors and post-BCG treatment, and Cluster 4 (55.7 %), consisting of patients with primary tumors and urine cytology class ≥ III. Clusters 1 and 2, consisting of patients without BCG treatment and patients with lower urine cytology classes, exhibited higher sensitivities (94.4 % and 87.7 %). Among all clusters, Cluster 4 had the highest proportion of specimens which were negative for both PDD and white light (WL) findings but actually had malignant lesions (20.8 %).

CONCLUSIONS

PDD-assisted TURBT sensitivity was lower in subclasses after BCG treatment or with cytology class III or higher. Random biopsy for PDD/WL double-negative lesions may improve diagnostic accuracy in these subclasses.

The prognostic impact of treatment centralization in patients with testicular germ cell tumors: analysis of hospital-based cancer registry data in Japan

BACKGROUND

To identify the prognostic impact of treatment centralization in patients with testicular germ cell tumors (TGCT).

METHODS

We used a hospital-based cancer registry data in Japan to extract seminoma and non-seminoma cases that were diagnosed in 2013, histologically confirmed, and received the first course of treatment. To compare the 5-years overall survival (OS) rates of patients stratified by institutional care volume, we performed a Cox proportional hazards regression analysis using inverse probability of treatment weighting (IPTW) method to adjust patient backgrounds.

RESULTS

A total of 1767 TGCT patients were identified. The 5-years OS rates for stage II and III TGCT patients treated at low-volume institutions (< 7 cases) were significantly worse than high-volume institutions (≥ 7 cases) (91.2% vs. 83.4%, p = 0.012). Histological stratification revealed that 5-year OS rates for stage II and III seminoma patients in the low-volume group were significantly worse than the high-volume group (93.5% vs. 84.5%, p = 0.041). Multivariate OS analysis using an IPTW-matched cohort showed that institutional care volume was an independent prognostic factor (hazard ratio 2.13 [95% confidence interval: 1.23-3.71], p = 0.0072).

CONCLUSION

Our results indicate that stage II and III TGCT patients experience lower survival rates at low-volume institutions and would benefit from treatment centralization.

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.

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.

Preoperative prognostic model for localized and locally advanced renal cell carcinoma: Michinoku Japan Urological Cancer Study Group

BACKGROUND

The Modified International Metastatic Renal Cell Carcinoma Dataset Consortium model (mIMDC) is a preoperative prognostic model for pT3cN0M0 renal cell carcinoma (RCC). This study aimed to validate the mIMDC and to construct a new model in a localized and locally advanced RCC (LLRCC).

METHODS

A database was established (the Michinoku Japan Urological Cancer Study Group database) consisting of 79 patients who were clinically diagnosed with LLRCC (cT3b/c/4NanyM0) and underwent radical nephrectomy from December 2007 to May 2018. Using univariable and multivariable analyses, we retrospectively analyzed disease-free survival (DFS) and overall survival (OS) in this database, constructed a new prognostic model according to these results, and estimated the model fit using c-index on the new and mIMDC models.

RESULTS

Independent poorer prognostic factors for both DFS and OS include the following: ≥ 1 Eastern Cooperative Oncology Group performance status, 2.0 mg/dL C-reactive protein, and > upper normal limit of white blood cell count. The median DFS in the favorable (no factor), intermediate (one factor), and poor-risk group (two or three factors) was 76.1, 14.3, and 4.0 months, respectively (P < 0.001). The 3-year OS in the favorable, intermediate, and poor-risk group were 92%, 44%, and 0%, respectively (P < 0.001). The c-indices of the new and mIMDC models were 0.67 and 0.60 for DFS (P = 0.060) and 0.74 and 0.63 for OS (P = 0.012), respectively.

CONCLUSION

The new preoperative prognostic model in LLRCC can be used in patient care and clinical trials.

The efficacy of molecular targeted therapy and nivolumab therapy for metastatic non-clear cell renal cell carcinoma: A retrospective analysis using the Michinoku Japan urological cancer study group database

OBJECTIVES

To investigate the efficacy of pharmacotherapy for metastatic non-clear cell renal cell carcinoma (nccRCC) in Japanese population.

METHODS

In this retrospective analysis, we compared the time to treatment failure (TTF) for molecular-targeted agents as first-line therapy, or nivolumab therapy as sequential therapy between ccRCC and nccRCC using the data of Japanese metastatic RCC patients registered in the Michinoku Japan Urological Cancer Study Group database.

RESULTS

In total, 511 cases of ccRCC and 77 cases of nccRCC were treated with pharmacotherapy. After excluding the patients who received cytokine therapy, chemotherapy, or others, there were 391 ccRCC patients and 60 nccRCC patients who were treated with tyrosine kinase inhibitors (TKIs), and 7 ccRCC patients and 7 nccRCC patients who were treated with mammalian-target of rapamycin inhibitors (mTORIs). In addition, 132 ccRCC patients and 16 nccRCC patients received nivolumab. There was no significant difference in IMDC risk classification before first-line therapy between ccRCC and nccRCC groups, or in each subgroup within the nccRCC group. TTF for TKIs (161 days, 95% CI: 75-212 days) and mTORIs (21 days, 95% CI: 9-31 days) didn't differ significantly between nccRCC and ccRCC groups (205 days, 95% CI: 174-243 days and 33 days, 95% CI: 8-113 days, respectively). TTF for TKIs was significantly longer than that for mTORIs in nccRCC group (p<0.01). There was no significant difference in TTF between the different TKIs in nccRCC group. In addition, no significant difference in TTF for nivolumab was seen between ccRCC and nccRCC groups.

CONCLUSIONS

The results showed that the efficacy of molecular-targeted agents as first-line therapy was similar oncological outcomes between metastatic nccRCC and ccRCC in Japanese patients. TKIs may be more effective than mTORIs in metastatic nccRCC patients. Nivolumab administration might also be as effective in nccRCC patients as in ccRCC patients in Japanese population.

Variant allele frequency changes in TP53 predict pembrolizumab response in patients with metastatic urothelial carcinoma

Prognoses for patients with metastatic urothelial carcinoma (mUC) have improved with pembrolizumab treatment, an immune checkpoint inhibitor, but clinical benefits are limited to a subset of patients. Therefore, a non-invasive biomarker to predict pembrolizumab response is required. The present study retrospectively examined genomic alterations in 25 plasma circulating tumor DNA (ctDNA) samples using targeted sequencing of 77 genes from 16 patients with mUC during pembrolizumab treatment. A total of 11 (68.8%) patients demonstrated ≥2 genomic alterations, including TP53 mutations (as defined by ctDNA-positive status). The proportion of responders to pembrolizumab in the ctDNA-positive group was higher compared with that in the ctDNA-negative group (72.7 vs. 20.0%). Furthermore, among all detected genomic alterations, variant allele frequency decreases in TP53 during pembrolizumab treatment were mainly associated with therapeutic response. Collectively, these data suggest that profiling of ctDNA in plasma, particularly TP53, may be useful for predicting and monitoring therapeutic responses to pembrolizumab in patients with mUC.

Pembrolizumab (pembro) monotherapy for patients (pts) with high-risk non–muscle-invasive bladder cancer (HR NMIBC) unresponsive to bacillus Calmette–Guérin (BCG): Results from cohort B of the phase 2 KEYNOTE-057 trial

LBA442

Background: Although most pts with HR NMIBC respond to BCG, pts whose cancer does not respond or who relapse within 12 mo have poor prognosis and require radical cystectomy (RC). The single-arm, multicohort phase 2 KEYNOTE-057 trial (NCT02625961) was designed to investigate the safety and efficacy of pembro monotherapy for pts with BCG-unresponsive HR NMIBC (per FDA) who were ineligible or declined to undergo RC. Results from cohort A (carcinoma in situ [CIS] ± papillary tumors) showed a clinical complete response rate of 41% at 3 mo and led to approval of pembro monotherapy for such pts in the United States. We describe the results from cohort B (papillary tumors without CIS). Methods: Pts were aged ≥18 y with BCG-unresponsive HR NMIBC with papillary tumors only (high-grade Ta or any-grade T1) at baseline and ECOG PS 0-2. Pts received pembro 200 mg every 3 wk (Q3W) for ≤35 cycles (~2 y). Cancer was assessed at 12 wk and Q12W thereafter if no recurrent HR NMIBC or progression was observed; CT urography was done Q24W. Primary end points for cohort B were 12-mo disease-free survival (DFS) rate of HR NMIBC as assessed by central pathology/radiology review and safety, assuming a 12-mo DFS of >20% for HR NMIBC. Secondary efficacy end points were 12-mo DFS rate of any disease; progression-free survival (PFS) to worsening of grade, stage, or death; PFS to muscle invasion, metastasis, or death; and overall survival (OS). Results: Overall, 132 pts received pembro for a median of 9.5 cycles (range, 1.0-35.0). Median age was 72 y (range, 37-87); 57 pts (43.2%) had T1 stage; all pts (100%) had urothelial histology; 104 pts (78.8%) were male; pts received a median of 10 (range, 6-33) prior BCG instillations. Median follow-up was 45.4 mo (range, 14.9-77.1). Efficacy data are shown in Table. Thirty-one pts (23.5%) had RC after stopping pembro. Treatment-related AEs occurred in 97 pts (73.5%); 19 (14.4%) had a grade 3/4 treatment-related AE and 14 pts (10.6%) discontinued due to a treatment-related AE. No deaths from treatment-related AEs occurred. Conclusions: Pembro showed notable antitumor activity in pts with BCG-unresponsive non-CIS papillary HR NMIBC after ~45 mo of follow-up. Toxicity was manageable and consistent with that in cohort A, with no new safety signals. Results suggest pts with non-CIS papillary HR NMIBC unresponsive to BCG who declined or were ineligible to undergo RC may also benefit from pembro monotherapy. Clinical trial information: NCT02625961 . [Table: see text]

Plasma circulating tumor DNA profiling in patients with chemo-refractory germ cell tumors

OBJECTIVES

Molecular analysis of tumor tissues has been extensively analyzed in germ cell tumors. However, genetic analysis of plasma circulating tumor DNA has been limited. Our objective was to analyze genetic alterations in circulating tumor DNA as well as its impact on prognosis in patients with chemo-refractory germ cell tumors.

METHODS

We included 13 patients with chemo-refractory germ cell tumors who relapsed after second-line or higher previous chemotherapy and performed targeted sequencing of plasma cell-free DNA using an AVENIO Expanded kit.

RESULTS

Tumor-specific genetic alterations were identified in all patients. The most frequently mutated gene was TP53 (53.4%), followed by PTEN (23.1%), GNAS (15.4%) and MTOR (15.4%). Moreover, EGFR amplification (38.5%) and MET amplification (15.4%) were also identified. We defined two or more single nucleotide variants detected in plasma cell-free DNA as circulating tumor DNA-positive. Kaplan-Meier analysis revealed that overall survival was significantly shorter in circulating tumor DNA-positive patients than circulating tumor DNA negative-patients (median overall survival 3.13 vs. 8.73 months; p = 0.042).

CONCLUSION

Analysis of plasma circulating tumor DNA could detect genetic alterations in patients with chemo-refractory GCT. Moreover, detectable circulating tumor DNA in plasma was associated with poor prognosis in those patients. These results suggest that liquid biopsy using analysis of plasma circulating tumor DNA may be clinically useful for germ cell tumor patients.

Glucocorticoids coordinate the bladder peripheral clock and diurnal micturition pattern in mice

Peripheral clocks function to regulate each organ and are synchronized though various molecular and behavioral signals. However, signals that entrain the bladder clock remain elusive. Here, we show that glucocorticoids are a key cue for the bladder clock in vitro and in vivo. A pBmal1-dLuc human urothelial cell-line showed significant shifts in gene expression after cortisol treatment. In vivo, rhythmic bladder clock gene expression was unchanged by bilateral adrenalectomy but shifted 4 h forward by corticosterone administration at the inactive phase. Moreover, the bladder clock shifted 8-12 h in mice that underwent both bilateral adrenalectomy and corticosterone administration at the inactive phase. These mice showed decreases in the diurnal rhythm of volume voided per micturition, while maintaining diurnal activity rhythms. These results indicate that the diurnal rhythm of glucocorticoid signaling is a zeitgeber that overcomes other bladder clock entrainment factors and coordinates the diurnal rhythm of volume voided per micturition.

Complete Response to Enfortumab Vedotin in a Hemodialysis Patient with Metastatic Urothelial Carcinoma: A Case Report

Enfortumab vedotin (EV) is an antibody-drug conjugate and a promising agent for metastatic urothelial carcinoma (mUC). However, evaluations in end-stage renal disease patients undergoing hemodialysis are unreported. Here, we report such a case. A 74-year-old woman with mUC, on hemodialysis for complete urinary tract extirpation, was diagnosed with multiple pulmonary metastases after treatment with gemcitabine-carboplatin followed by pembrolizumab. As third-line therapy, she received a standard dose of EV. She achieved complete response after 2 cycles without grade 3 or higher adverse events, demonstrating the utility of EV in this setting.

Whole-Blood Gene Expression Profiles Correlate with Response to Immune Checkpoint Inhibitors in Patients with Metastatic Renal Cell Carcinoma

In metastatic renal cell carcinoma (mRCC), the clinical response to immune checkpoint inhibitors (ICIs) is limited in a subset of patients and the need exists to identify non-invasive, blood-based, predictive biomarkers for responses. We performed RNA sequencing using whole-blood samples prospectively collected from 49 patients with mRCC prior to the administration of ipilimumab (IPI) and/or nivolumab (NIVO) to determine whether gene expression profiles were associated with responses. An analysis from 33 mRCC patients with complete responses (n = 5), partial responses (n = 14), and progressive disease (n = 14) showed 460 differentially expressed genes (DEGs) related to immune responses between the responder and non-responder groups with significant differences. A set of 14 genes generated from the initial 460 DEGs accurately classified responders (sensitivity 94.7% and specificity 50.0%) while consensus clustering defined clusters with significantly differing response rates (92.3% and 35.0%). These clustering results were replicated in a cohort featuring 16 additional SD patients (49 total patients): response rates were 95.8% and 48.0%. Collectively, whole-blood gene expression profiles derived from mRCC patients treated with ICIs clearly differed by response and hierarchical clustering using immune response DEGs accurately classified responder patients. These results suggest that such screening may serve as a predictor for ICI responses in mRCC patients.

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.

Laparoendoscopic single-site surgery for urachal remnant with extraperitoneal approach through a suprapubic port

INTRODUCTION

No standard procedure has been established for laparoendoscopic single-site surgery for urachal remnants (LESS-U). This study aimed to report the novel surgical techniques and initial outcomes of laparoendoscopic single-site surgery with an extraperitoneal approach through a suprapubic port for urachal remnants (spLESS).

METHODS

Fifty-five patients (median age, 27 years; range, 15-69 years) who underwent LESS-U were analyzed. To overcome the limitations inherent in the conventional procedure (LESS-U through an umbilical port: uLESS), we modified the port placement and approached via the extraperitoneal space. spLESS is a novel procedure which reduces intestinal damage caused by the extraperitoneal approach and overcomes incomplete resection of the urachal remnant, especially in the bladder dome. Three trocars are inserted into the extraperitoneal space through a suprapubic port in spLESS, and complete resection of the urachal remnant from the umbilicus to the bladder is performed with an appropriate incision line. Patient characteristics and perioperative results were retrospectively collected. Cosmetic outcomes were prospectively evaluated using self-administered questionnaires (body image and photo-series questionnaire).

RESULTS

spLESS and uLESS were performed in 43 and 12 patients, respectively. No differences were observed between the perioperative results. The cosmetic outcomes were compared between the groups using body image and photo-series questionnaires. No patient developed major complications; there was no recurrence in either group.

CONCLUSIONS

spLESS is a novel procedure which can completely resect the urachal remnant and reduce the risk of intestinal damage. spLESS is a safe, effective, and feasible procedure with high postoperative cosmesis.

ELOVL5-mediated fatty acid elongation promotes cellular proliferation and invasion in renal cell carcinoma

Renal cell carcinoma (RCC) features altered lipid metabolism and accumulated polyunsaturated fatty acids (PUFAs). Elongation of very long–chain fatty acid (ELOVL) family enzymes catalyze fatty acid elongation, and ELOVL5 is indispensable for PUFAs elongation, but its role in RCC progression remains unclear. Here, we show that higher levels of ELOVL5 correlate with poor RCC clinical prognosis. Liquid chromatography/electrospray ionization‐tandem mass spectrometry analysis showed decreases in ELOVL5 end products (arachidonic acid and eicosapentaenoic acid) under CRISPR/Cas9‐mediated knockout of ELOVL5 while supplementation with these fatty acids partially reversed the cellular proliferation and invasion effects of ELOVL5 knockout. Regarding cellular proliferation and invasion, CRISPR/Cas9‐mediated knockout of ELOVL5 suppressed the formation of lipid droplets and induced apoptosis via endoplasmic reticulum stress while suppressing renal cancer cell proliferation and in vivo tumor growth. Furthermore, CRISPR/Cas9‐mediated knockout of ELOVL5 inhibited AKT Ser473 phosphorylation and suppressed renal cancer cell invasion through chemokine (C‐C motif) ligand‐2 downregulation by AKT‐mTOR‐STAT3 signaling. Collectively, these results suggest that ELOVL5‐mediated fatty acid elongation promotes not only cellular proliferation but also invasion in RCC.

Phase II trial of nivolumab monotherapy and biomarker screening in patients with chemo‐refractory germ cell tumors

Objectives

Germ cell tumors are highly susceptible to chemotherapy; however, there is a lack of established treatments for consistently relapsing germ cell tumor. Therefore, in this phase II study, we evaluated the efficacy and safety of nivolumab for relapsed germ cell tumor.

Methods

Seventeen adult patients (median age 34 years) with refractory primary germ cell tumor after second‐line or higher chemotherapy were enrolled. Nivolumab was administered over 30 min at 240 mg/body every 2 weeks until disease progression or intolerable adverse event occurrence. The primary endpoint was the overall response rate.

Result

We performed a biomarker analysis of programmed death ligand‐1 expression and genomic sequencing. Tumor histology revealed nonseminoma and seminoma in 14 and three patients, respectively. Patients were pretreated with a median of three chemotherapy lines, and three patients received high‐dose chemotherapy. The median number of nivolumab doses was 3 (range 2–46). One patient showed a partial response and three showed stable disease. Responses were durable in one patient with a partial response and one patient with stable disease (median 90 and 68 weeks, respectively). Nivolumab was well‐tolerated, with only two Grade 3 adverse events observed. Programmed death ligand‐1 expression was not associated with objective responses. Genomic sequencing revealed a high tumor mutation burden in a patient with a durable partial response. While a small subset of chemorefractory germ cell tumors may respond to nivolumab, programmed death ligand‐1 is unreliable to measure response.

Conclusions

Tumor mutation burden is a potential biomarker for future testing of germ cell tumor response.

[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.

Case Report: Molecular Characterization of Aggressive Malignant Retroperitoneal Solitary Fibrous Tumor: A Case Study

Solitary fibrous tumors (SFT) are mesenchymal neoplasms with a favorable prognosis usually originating from the visceral pleura. Rarely, they may occur at various extrapleural sites and show malignant behavior coupled with dedifferentiation. NAB2-STAT6 fusion gene and STAT6 nuclear expression are biomarkers for diagnosis of SFT in addition to CD34, Bcl-2, and CD99. Furthermore, several reports have shown specific NAB2-STAT6 fusion variants and loss of STAT6 protein expression are associated with malignancy. We report a rare case of retroperitoneal SFT which rapidly progressed to death within 35 days after admission. Autopsy found a primary tumor containing both benign and malignant histologies, with multiple metastatic sites similar to the malignant, dedifferentiated tumor. STAT6 was detected in the primary differentiated tumor but not in the primary dedifferentiated tumor or lung/liver metastases. However, the NAB2-STAT6 fusion gene (NAB2ex6/STAT6ex16 variant) was detected in the primary tumor and lung/liver metastases. Intriguingly, fusion gene expression at the transcriptional level was downregulated in the dedifferentiated tumors compared to the differentiated tumor. We further performed target DNA sequencing and found gene mutations in TP53, FLT3, and AR in the dedifferentiated tumors, with TP53 mutations especially found among them. We demonstrate that downregulation of NAB2-STAT6 fusion gene at the transcriptional level is associated with malignant SFT for the first time. Moreover, the present study supports the idea that TP53 mutations promote malignancy in SFTs.

Clinical Utility of Germline Genetic Testing in Japanese Men Undergoing Prostate Biopsy

Background

Multiple common variants and also rare variants in monogenic risk genes such as BRCA2 and HOXB13 have been reported to be associated with risk of prostate cancer (PCa); however, the clinical setting in which germline genetic testing could be used for PCa diagnosis remains obscure. Herein, we tested the clinical utility of a 16 common variant–based polygenic risk score (PRS) that has been developed previously for Japanese men and also evaluated the frequency of PCa-associated rare variants in a prospective cohort of Japanese men undergoing prostate biopsy.

Methods

A total of 1336 patients undergoing first prostate biopsy were included. PRS was calculated based on the genotype of 16 common variants, and sequencing of 8 prostate cancer–associated genes was performed by multiplex polymerase chain reaction based target sequencing. PRS was combined with clinical factors in logistic regression models to assess whether addition of PRS improves the prediction of biopsy positivity.

Results

The top PRS decile was associated with an odds ratio of 4.10 (95% confidence interval = 2.46 to 6.86) with reference to the patients at average risk, and the estimated lifetime absolute risk approached 20%. Among the patients with prostate specific antigen 2-10 ng/mL who had prebiopsy magnetic resonance imaging, high PRS had an equivalent impact on biopsy positivity as a positive magnetic resonance imaging finding. Rare variants were detected in 19 (2.37%) and 7 (1.31%) patients with positive and negative biopsies, respectively, with BRCA2 variants being the most prevalent. There was no association between PRS and high-risk rare variants.

Conclusions

Germline genetic testing could be clinically useful in both pre- and post-PSA screening settings.

Granulocyte colony-stimulating factor associated arteritis in a patient with castration-resistant prostate cancer

INTRODUCTION

Granulocyte colony-stimulating factor-associated arteritis is a rare adverse event of granulocyte colony-stimulating factor, with an incidence of 0.47% among all patients who receive granulocyte colony-stimulating factor. We herein present a case of granulocyte colony-stimulating factor-associated arteritis.

CASE PRESENTATION

A 72-year-old man with castration-resistant prostate cancer and multiple bone metastases was treated with docetaxel and pegfilgrastim. He developed a high fever on day 12 without other symptoms. His white blood cell count and C-reactive protein levels were high. Antibiotic therapy was ineffective, and contrast-enhanced computed tomography showed thickened subclavian and brachiocephalic artery walls. He was diagnosed with granulocyte colony-stimulating factor-associated arteritis.

CONCLUSION

When patients receiving chemotherapy with granulocyte colony-stimulating factor develop an unexplained fever, granulocyte colony-stimulating factor associated arteritis should be considered.

ELOVL2 promotes cancer progression by inhibiting cell apoptosis in renal cell carcinoma

Renal cell carcinoma (RCC) is an aggressive genitourinary malignancy which has been associated with a poor prognosis, particularly in patients with metastasis, its major subtypes being clear cell RCC (ccRCC), papillary PCC (pRCC) and chromophobe RCC (chRCC). The presence of intracellular lipid droplets (LDs) is considered to be a hallmark of ccRCC. The importance of an altered lipid metabolism in ccRCC has been widely recognized. The elongation of very-long-chain fatty acid (ELOVL) catalyzes the elongation of fatty acids (FAs), modulating lipid composition, and is required for normal bodily functions. However, the involvement of elongases in RCC remains unclear. In the present study, the expression of ELOVL2 in ccRCC was examined; in particular, high levels of seven ELOVL isozymes were observed in primary tumors. Of note, elevated ELOVL2 expression levels were observed in ccRCC, as well as in pRCC and chRCC. Furthermore, a higher level of ELOVL2 was significantly associated with the increased incidence of a poor prognosis of patients with ccRCC and pRCC. The CRISPR/Cas9-mediated knockdown of ELOVL2 resulted in the suppression of the elongation of long-chain polyunsaturated FAs and increased LD production in renal cancer cells. Moreover, ELOVL2 ablation resulted in the suppression of cellular proliferation via the induction of apoptosis in vitro and the attenuation of tumor growth in vivo. On the whole, the present study provides new insight into the tumor proliferation mechanisms involving lipid metabolism, and suggests that ELOVL2 may be an attractive novel target for RCC therapy.

External validation of the REMARCC model for the selection of cytoreductive nephrectomy in patients with primary metastatic renal cell carcinoma: A multicenter retrospective study

OBJECTIVES

This study aims to evaluate the utility of the scoring system of the Registry for Metastatic Renal Cell Carcinoma (REMARCC) model on the overall survival (OS) of patients undergoing cytoreductive nephrectomy (CN).

METHODS

A total of 278 patients with primary metastatic renal cell carcinoma (mRCC) treated with first-line tyrosine kinase inhibitors (TKIs) between January 2008 and November 2019 were identified. The c-index and net benefit between the REMARCC score were compared with the International mRCC Database Consortium (IMDC) score in patients with CN (CN group, n = 146). The effect of the REMARCC score on OS was compared between the CN group and patients without CN (non-CN group, n = 132) using Cox regression analysis under the propensity score-based inverse probability of treatment weighting (IPTW) method to adjust for group imbalances.

RESULTS

Of the 146 patients with CN, the c-index of the REMARCC model (0.60) was higher than the IMDC model (0.54). The decision curve analysis showed the advantage of REMARCC model predicting OS compared with the IMDC model. OS was significantly longer in the REMARCC low-score (0-2) than that in the high-score (3-6) among the patients with CN. IPTW-adjusted Cox regression analyses showed that OS was significantly longer in the CN group than that in the non-CN group among the patients with REMARCC low-score but was not significantly different between the groups among the patients with REMARCC high-score.

CONCLUSIONS

The REMARCC score may be active for selecting the CN candidate in patients treated with TKIs.

Prognosis of Japanese metastatic renal cell carcinoma patients in the targeted therapy era

BACKGROUND

The aims of this study were to investigate prognosis and validate prognostic models [Memorial Sloan-Kettering Cancer Center (MSKCC), International Metastatic Renal Cell Carcinoma Data Consortium (IMDC), and Japanese metastatic renal cancer (JMRC) models] in the targeted therapy era in Japanese patients with metastatic renal cell carcinoma.

METHODS

We retrospectively analyzed 692 patients who were diagnosed with mRCC from January 2008 to August 2018 in the Michinoku Japan Urological Cancer Study Group database. Nivolumab as sequential therapy was widely used. Other immune checkpoint inhibitors were excluded from this study.

RESULTS

The median overall survival (95% confident interval) in all, MSKCC favorable, intermediate, and poor risk patients was 41.0 months (33.9-46.8), not reached (63.5 to not estimable), 46.8 months (37.1-52.9), and 10.4 months (8.9-14.4), respectively. The median overall survival (95% confident interval) in IMDC favorable, intermediate, and poor risk patients was not reached (61.6 to not estimable), 47.4 months (41.4-56.5), and 11.5 (9.9-16.3), respectively. The c-index of the MSKCC, IMDC, and JMRC models calculated at mRCC diagnosis was 0.680, 0.689, and 0.700, respectively. No statistical differences were found in the c-index among the models.

CONCLUSION

While the real-world overall survival in Japanese patients with mRCC in the targeted therapy era improved compared to that previously reported in the cytokine era, there was no clear difference in the survival of poor risk patients between these eras. There were no differences in the superiority among the models.

Advanced germ cell tumor patients undergoing post-chemotherapy retroperitoneal lymph node dissection: Impact of residual teratoma on prognosis

OBJECTIVES

To evaluate the histologic findings and clinical outcomes of post-chemotherapy retroperitoneal lymph node dissection for advanced germ cell tumor.

METHODS

We analyzed the medical records of 66 patients who underwent post-chemotherapy retroperitoneal lymph node dissection between 2005 and 2019 at Tsukuba University Hospital.

RESULTS

The proportions of necrosis, teratoma, and viable germ cell tumor in the specimens were 62.1%, 36.4%, and 1.5%, respectively. The 5-year progression-free and overall survival rates were 82.3% and 91.3%, respectively. The 5-year overall survival rate of patients with residual teratoma was significantly worse than that of patients with necrosis only (74.1% vs 100%). Overall, three patients died: one from cancer and two from teratoma with somatic-type malignancy. Of these, two patients relapsed after incomplete resection of residual teratoma. When limited to patients with completely resected teratoma, the 5-year overall survival rate was 91.7%, which did not differ from that for patients with necrosis only. Multivariate analysis showed that presence of teratoma in the primary site and decrease in retroperitoneal lymph node mass to less than 50% of the initial tumor size were independent factors for residual teratoma. However, the absence of these factors could not reliably predict necrosis only in retroperitoneal lymph node dissection specimens.

CONCLUSIONS

In our series, 98% of post-chemotherapy retroperitoneal lymph node dissection pathology was either necrosis or teratoma, with viable germ cell tumor only found in 2% of patients. Residual teratoma was associated with poorer prognosis, especially in cases of incomplete resection.

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.

PLD1 promotes tumor invasion by regulation of MMP-13 expression via NF-κB signaling in bladder cancer

Invasion of bladder cancer (BC) cells from the mucosa into the muscle layer is canonical for BC progression while phospholipase D isoform 1 (PLD1) is known to mediate development of cancer through phosphatidic acid (PA) production. We therefore used in silico, in vitro and in vivo approaches to detail the effect of PLD1 on BC invasion. In BC patients, higher levels of PLD1 expression were associated with poor prognoses. PLD1 knockdown significantly suppressed cellular invasion by human BC cells and matrix metalloproteinase-13 (MMP-13) was observed to mediate this effect. In our mouse bladder carcinogenesis model, the development of invasive BCs was suppressed by PLD1 knockout and a global transcriptomic analysis in this model indicated MMP-13 as a potential tumor invasion gene with NF-κB (nuclear factor-kB) as its transcriptional regulator. Furthermore, PA administration increased MMP-13 expression in line with NF-κB p65 phosphorylation levels. Collectively, we demonstrate that PLD1 promotes tumor invasion of BC by regulation of MMP-13 expression through the NF-κB signaling pathway and that PLD1 might be a potential therapeutic target to prevent clinical progression in BC patients.

Retroperitoneal lymph node dissection for testicular cancer in a patient with a double inferior vena cava

INTRODUCTION

A double inferior vena cava is a rare anomaly with an incidence ranging from 0.3% to 3.0%. In patients with a double inferior vena cava, it is important to understand the precise anatomy and possible irregular lymph node flow when performing surgery for malignancies.

CASE PRESENTATION

A 60-year-old man with a non-seminoma was referred to our hospital after left high orchiectomy. Computed tomography revealed a double inferior vena cava and swollen masses in the para-aortic region. After four cycles of chemotherapy with etoposide and cisplatin, retroperitoneal lymph node dissection was safely performed with a modified template extended to the right side of the paracaval region by referring to three-dimensional images created by SYNAPSE VINCENT® software.

CONCLUSION

Preoperative three-dimensional images were useful to understand this patient's unusual and complicated anatomical positions.

The liposome of trehalose dimycolate extracted from M. bovis BCG induces antitumor immunity via the activation of dendritic cells and CD8+ T cells

Intravesical Bovis bacillus Calmette-Guérin (BCG) therapy is the most effective immunotherapy for bladder cancer, but it sometime causes serious side effects because of its inclusion of live bacteria. It is necessary to develop a more active but less toxic immunotherapeutic agent. Trehalose 6,6'-dimycolate (TDM), the most abundant hydrophobic glycolipid of the BCG cell wall, has been reported to show various immunostimulatory activities such as granulomagenesis and adjuvant activity. Here, we developed cationic liposomes incorporating TDM purified from Mycobacterium bovis BCG Connaught, and we investigated the antitumor effect of the cationic liposome TDM (Lip-TDM). Lip-TDM exerted an antitumor effect in bladder cancer, colon cancer, and melanoma-bearing mouse models that was comparable or even superior to that of BCG, with no body weight loss or granuloma formation. The antitumor effect of Lip-TDM disappeared in two types of mice: those with depletion of CD8⁺ T cells, and those with knockout of macrophage-inducible C-type lectin (Mincle) which recognize TDM. Lip-TDM treatment enhanced the maturation and migration of dendritic cells in the tumor microenvironment in a Mincle-dependent manner. Our results elucidate mechanisms that underlie Lip-TDM treatment and suggest that Lip-TDM has potential as a safe and effective treatment for various cancers.

Impact of Early Exposure to Simulation Program on Undergraduate Medical Students' Interest in Urology

BACKGROUND

Urological education is as important as surgical training for undergraduates. However, students in undergraduate medical schools have less exposure to urology as their curriculum focuses more on clinical skills, particularly community-based healthcare for a super-aging society. This study aimed to evaluate whether urology-related hands-on training could increase the interest of undergraduate medical students in urology.

METHODS

A 1-day elective program in urological surgery at the University of Tsukuba, particularly in robotic, laparoscopic, and endoscopic surgeries, was offered to 85 fourth-year medical students from 2018 to 2020, prior to their clinical clerkship. The average age of the participants was 22 (range: 21-25) years. We used a scoring system that comprised 1-5 Likert-type items to assess training activity, interest in surgery, and interest in urology before and after the course.

RESULTS

Before attending the program, the average scores of interest in urology were 3.53 in 2018, 3.15 in 2019, and 3.00 in 2020. The scores in surgery increased after the program; however, this was not significantly different from scores prior to the program. However, the average interest scores in urology were significantly increased to 3.91 ± 0.63 (P < .05), 3.88 ± 0.58 (P < .01), and 4.00 ± 0.61 (P < 0.01) in 2018, 2019, and 2020, respectively. Total likely scores of this program in 2018, 2019, and 2020 were 4.59, 4.76, and 4.88, respectively, indicating a motivation to study surgery and urology during clinical clerkship.

CONCLUSIONS

Urological hands-on training facilitated interest in urology in medical students prior to their clinical clerkship.

Impact of cytoreductive nephrectomy in patients with primary metastatic renal cell carcinoma receiving systemic tyrosine kinase inhibitor therapy: A multicenter retrospective study

OBJECTIVES

To compare overall survival between patients with metastatic renal cell carcinoma treated by cytoreductive nephrectomy and those not treated by cytoreductive nephrectomy.

METHODS

We retrospectively evaluated 278 patients with metastatic renal cell carcinoma treated with first-line tyrosine kinase inhibitors between January 2008 and November 2019. Patients were divided into two groups: a cytoreductive nephrectomy group (immediate or deferred cytoreductive nephrectomy) and a group who received systemic tyrosine kinase inhibitor therapies alone without cytoreductive nephrectomy (control group). Overall survival comparisons were made in all patients in the control versus the cytoreductive nephrectomy group, the control versus the immediate cytoreductive nephrectomy group, the control versus the deferred cytoreductive nephrectomy group, and the deferred cytoreductive nephrectomy versus the immediate cytoreductive nephrectomy group. Analyses were weighted using the propensity score-based inverse probability of treatment weighting method to adjust for group imbalances.

RESULTS

The median (range) age of the patients was 65 (59-73) years. Of the 278 patients, 132 and 146 were in the control group and the cytoreductive nephrectomy (immediate, n = 107 and deferred, n = 39) group, respectively. A significant difference was noted between the control and cytoreductive nephrectomy groups in age, clinical stage, International Metastatic Renal Cell Carcinoma Database Consortium risk factors, and the number of metastatic sites. Inverse probability of treatment weighting-adjusted Cox regression analysis showed a significant difference in overall survival between the control and the cytoreductive nephrectomy groups and between the control and the immediate or deferred cytoreductive nephrectomy groups. However, there was no significant difference in overall survival between the immediate and the deferred cytoreductive nephrectomy groups.

CONCLUSIONS

Our findings suggest that metastatic renal cell carcinoma patients undergoing cytoreductive nephrectomy are more likely to have longer overall survival than those who receive tyrosine kinase inhibitor therapy only.

Bladder preservation therapy for muscle invasive bladder cancer: the past, present and future

Radical cystectomy is the gold standard treatment for muscle invasive bladder cancer, but some patients have medically inoperable disease or refuse cystectomy to preserve their bladder function. Bladder preservation therapy with transurethral resection of the bladder tumor and concurrent chemoradiotherapy, known as trimodal treatment, is regarded to be a curative-intent alternative to radical cystectomy for patients with muscle invasive bladder cancer during the past decade. After the development of immune checkpoint inhibitors, a world-changing breakthrough occurred in the field of metastatic urothelial carcinoma and many clinical trials have been conducted against non-muscle invasive bladder cancer. Interestingly, preclinical and clinical studies against other malignancies have shown that immune checkpoint inhibitors interact with the radiation-induced immune reaction. As half of the patients with muscle invasive bladder cancer are elderly, and some have renal dysfunction, not only as comorbidity but also because of hydronephrosis caused by their tumors, immune checkpoint inhibitors are expected to become part of a new therapeutic approach for combination treatment with radiotherapy. Accordingly, clinical trials testing immune checkpoint inhibitors have been initiated to preserve bladder for muscle invasive bladder cancer patients using radiation and immune checkpoint inhibitors with/without chemotherapy. The objective of this review is to summarize the evidence of trimodal therapy for muscle invasive bladder cancer during the past decade and to discuss the future directions of bladder preservation therapy in immuno-oncology era.

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.

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.

[Rare Cancers in the Genitourinary Tract]

Many types of rare cancers develop in the genitourinary tract. However, guidelines underlying clinical practice have not been established due to the lack of nationwide epidemiological data for many of these cancers. While epidemiological data in Western countries has been revealed by population-based study, it has been attempted to build the data using hospital-based cancer registry(HBCR)in Japan. The data from nationwide designated cancer care hospitals and other core cancer care hospitals includes the patients' demographics, tumor characteristics, and the first course of treatment. Although HBCR data does not reflect the status of clinical practice at all hospitals, it may be a useful tool for understanding the actual practice of rare cancers in Japan. We focused on the current status and prospects of penile and urachal cancer, which are relatively common in daily clinical practice. A standard of care has not been established for penile and urachal cancer patients, and the prognoses of those patients are poor. Recently, genomic analysis using a next-generation sequencer has been actively performed for many types of cancer. It is an important future task to establish a standard of care for patients with rare cancers based on molecular biological characteristics through active genomic analysis.

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.

Predictors of venous thromboembolism development before and during chemotherapy for advanced germ cell tumor

OBJECTIVE

We retrospectively analyzed the incidence and localization of venous thromboembolism in patients undergoing chemotherapy for advanced germ cell tumor and separately evaluated the risk factors for venous thromboembolism development before and during chemotherapy.

METHODS

We included 121 patients treated with cisplatin-based chemotherapy between 2005 and 2018. Venous thromboembolism was defined as venous thrombosis diagnosed using radiological imaging with or without thromboembolic symptoms. We analyzed the clinical parameters for identifying the possible venous thromboembolism risk factors. Khorana score was used to calculate the venous thromboembolism risk.

RESULTS

Thirteen patients showed prechemotherapy venous thromboembolism and 13 developed venous thromboembolism during chemotherapy. The most common venous thromboembolism was deep vein thrombosis (10 patients), followed by inferior vena cava thrombus (eight patients) and pulmonary thrombus (six patients). Compared to the group without venous thromboembolism, the group with prechemotherapy venous thromboembolism showed higher proportion of patients with tumors originating in the right testis (10 out of 13), significantly higher lactate dehydrogenase levels (828 IU/L versus 436 IU/L, P = 0.013), significantly higher proportion of patients with retroperitoneal lymph node (RPLN) metastases >5 cm in diameter (76.9% versus 33.7%, P = 0.003) and slightly higher proportion of patients with high-risk Khorana score (≥ 3; 30.8% versus 11.6%). No significant differences were observed between the clinical characteristics of patients with venous thromboembolism developed during chemotherapy and patients without venous thromboembolism.

CONCLUSIONS

We show that both RPLN mass > 5 cm and high lactate dehydrogenase levels are significant risk factors for prechemotherapy venous thromboembolism but not for venous thromboembolism development during chemotherapy.

Clinicopathological features and their impacts on the prognoses of patients with nonurothelial carcinoma: A hospital-based cancer registry in Japan

555

Background: Urothelial carcinoma (UC) is the most common histology of genitourinary (GU) tract cancer. Non-UC tumors in the GU tract appear to be more aggressive than UC at that location, but the clinicopathological features and their impacts on the prognoses of the non-UC patients are not known due to the low numbers of these patients. Methods: We used Hospital-Based Cancer Registry (HBCR) data in Japan to extract non-UC cases, i.e., patients with adenocarcinoma (AC), squamous cell carcinoma (SCC), or small cell carcinoma (SmCC) of the GU tract who were diagnosed in 2008–2009 with histological confirmation and had received first course of treatment. We retrospectively analyzed the clinicopathological features of these patients, stratified by the bladder and the upper urinary tract (UUT) as tumor locations. We used a Cox proportional hazards regression to identify prognostic factors associated with the overall survival (OS). Results: Of the 8,095 cases at the bladder and 2,580 cases at the UUT, 384 (4.7%) and 131 (5.1%) non-UC cases were identified, respectively. The proportions of histologic subtypes in the bladder were 1.7% AC, 2.4% SCC, and 0.7% SmCC. In the UUT group, these proportions were 1.3%, 3.4%, and 0.4%, respectively. At both tumor locations, the distribution of ages was similar across all subtypes, with the age peak in the 70s. More patients with non-UC were diagnosed at an advanced clinical stage compared to the patients with UC at either location. The 5-yr OS rates of the non-UC patients with a tumor in the bladder and at the UUT were 40% and 26%, whereas the corresponding 5-yr OS rates among the UC patients were 61% and 52%, respectively. A multivariate analysis revealed that the presence of non-UC was significantly associated with increased mortality (hazard ratio 1.66, 95% confidence interval 1.48–1.87) regardless of the tumor location. Conclusions: The clinicopathological features of the non-UC patients were similar between both tumor locations. The presence of non-UC was associated with poor prognosis regardless of the tumor location. A standard of care must be established for non-UC patients, since the prognoses of these patients are not satisfactory.

Discrepancy between clinical stage and pathological stage based on the tumor location of urothelial carcinoma: A hospital-based cancer registry in Japan

579

Background: Accurate staging in patients with urothelial carcinoma (UC) of the bladder (UCB) or the upper urinary tract (UTUC) is essential for planning the appropriate treatment strategy. Although an underestimation of the pathological stage may result in missing the opportunity to perform preoperative treatment, the actual rate of the discrepancy between the clinical and pathological stages in UC is not known. Methods: We used Hospital-Based Cancer Registry (HBCR) data in Japan to extract 3,747 cases of UCB and 6,831 cases of UTUC with cT1-4N0M0 that were diagnosed in 2012–2015, histologically confirmed, and treated with radical surgery. We excluded patients who received chemotherapy or radiotherapy and those with an unknown clinical or pathological stage. Results: The proportion of UCB patients whose pathological stage was up-staged was 25%, and that of the UTUC patients was 30%. Among the patients with cT1 at each tumor location, up-staging to muscle-invasive cancer occurred in 30.9% (UCB, n=1132: pT2, 21.6%; pT3, 7.9%; pT4, 1.5%) and 37.5% (UTUC, n=2526: pT2, 16.9%; pT3, 20.2%; pT4, 0.4%), respectively. In particular, in the group of UTUC patients with cT1, the proportion of up-staging for pT3 was higher than that in the group of UCB patients with cT1. In the cases with cTis, up-staging to muscle-invasive cancer occurred in 10.5% (UCB, n=391: pT2, 6.9%; pT3, 1.8%; pT4, 1.8%) and 18.5% (UTUC, n=872: pT2, 9.7%; pT3, 8.7%). In contrast, the proportion of down-staging to non-muscle-invasive cancer in cases with cT2 or higher was 12% in the UCB group (n=2291) and 15% in the UTUC group (n=504). Conclusions: Among UC patients, up-staging from non-muscle-invasive cancer to muscle-invasive cancer is relatively common, and the frequency of this discrepancy in clinical and pathological stages tends to be especially higher in UTUC patients. More accurate diagnostic imaging techniques and biomarkers are urgently needed for the identification of the appropriate UC candidates for preoperative treatment.

Molecular mechanism of FGFR activation and resulting differences in the tumor-immune environment of bladder cancer

432

Background: Activation of FGFR signals in bladder cancer is frequently observed. Previous study reported that infiltration of tumor immune cells is suppressed in FGFR3 mutated bladder cancer. In this study, we elucidate the relationship between molecular mechanism of FGFR activation and tumor immune environment in bladder cancer. Methods: We analyzed 103 tissues of bladder cancer patients. Detection of somatic mutations were performed by target sequencing and gene expressions were analyzed by RNA-seq. Immunohistochemical staining of CD8 was performed for evaluating tumor-infiltrating lymphocytes. We compared the relationship between molecular mechanism of FGFR activation and tumor immune environment. Results: FGFR3 activated mutation or fusion was found in 37 cases (36%). FGFR1 overexpression was found in 10 cases (10%). FGFR3 activated mutation or fusion and FGFR1 overexpression were mutually exclusive. Tumors harboring FGFR3 mutation showed less infiltration of CD8 positive cells ( p = 0.01) and low PD-L1 expression ( p = 0.08) compared to those without. On the other hand, tumors with FGFR1 overexpression showed more infiltration of CD8 positive cells ( p = 0.06) and high PD-L1 expression ( p = 0.02). Conclusions: Clinicopathological features and intratumor immune environment of bladder cancer is different depending on the molecular mechanism of FGFR activation. These results suggest a possible association between molecular mechanism of FGFR activation and sensitivity of immunotherapy.

Impact of hemoglobin levels on hemoglobin-adjusted carbon monoxide diffusion capacity after chemotherapy for testicular cancer

OBJECTIVES

We aimed to compare the diffusion capacity of carbon monoxide (DLCO), which was adjusted using the two equations the Cotes method and the Dinakara method, to assess bleomycin-induced lung injury in testicular cancer patients preparing for post-chemotherapy surgery.

METHODS

Between November 1990 and October 2018, 89 patients with advanced testicular cancer were recruited into the study. All patients received chemotherapy and underwent DLCO measurements using the single-breath technique prior to surgery for residual tumor removal.

RESULTS

The mean DLCO adjusted for hemoglobin using the Cotes and Dinakara methods was 69.5% and 86.0%, respectively (P < 0.001). According to the Cotes method, adjusted DLCO was severely diminished to below 65% in 40 patients (45%), whereas this proportion was only 16% according to the Dinakara method. We observed a significant correlation between hemoglobin levels and DLCO adjusted using the Cotes method (P < 0.001), but not using the Dinakara method. Four patients received a clinical diagnosis of bleomycin-induced pneumonitis (BIP), and all patients recovered after oral steroid therapy or observation. The DLCO adjusted by either methods was not well correlated with the development of BIP. No patients had major postoperative respiratory complications.

CONCLUSIONS

We found that Cotes-adjusted DLCO may be influenced by anemia. We recommend the addition of Dinakara-adjusted DLCO, along with chest computed tomography, for preoperative risk assessment.