A contemporary comparison of laparoscopic versus open partial nephrectomy for renal cell carcinoma.

PURPOSE: To analyze surgical and oncologic outcomes of patients undergoing open partial nephrectomy (OPN) versus laparoscopic partial nephrectomy (LPN) for treatment of renal cell carcinoma (RCC). METHODS: We retrospectively investigated our institutional RCC database for patients who underwent PN for RCC from 1997 to 2018. Decision for technique was at the discretion of the operating urologist, following practice patterns and training history. Outcomes analyzed included pre/peri/post-operative parameters, pathologic outcomes, and disease recurrence rates. RESULTS: 1088 patients underwent PN from 1997 to 2018. After exclusionary criteria, 631 patients who underwent 647 unique PNs for a total of 162 OPN and 485 LPN remained. Baseline, pre-op, and pathologic characteristics were not statistically different. Surgical time was lower in laparoscopic cases [185 vs. 205 min] (p = 0.013). Margin involvement was not statistically different; LPN had lower estimated blood loss (EBL) [150 vs. 250 mL] (p < 0.001) and longer ischemia time [21 vs. 19 min] (p = 0.005). LPN had shorter length of stay [2 vs. 4 days] (p < 0.001), fewer overall complications (p < 0.001), and no significant difference in high-grade complications [2.89 vs. 4.32%] (p = 0.379). Fewer LPN patients developed metastases [1.65 vs. 4.94%] (p = 0.0499). Local recurrence rates were not statistically different [1.24 vs. 3.09%] (p = 0.193). Renal function was equivalent between cohorts post-operatively. CONCLUSION: Long-term oncologic outcomes were not significantly different between LPN versus OPN, with no statistical difference in patient and tumor characteristics. LPN was associated with lower EBL, shorter length of stay, and lower overall complication risk. Renal function was not significantly different between cohorts.

Genomic Tumor Correlates of Clinical Outcomes Following Organ-Sparing Chemoradiation Therapy for Bladder Cancer.

PURPOSE: There is an urgent need for biomarkers of radiation response in organ-sparing therapies. Bladder preservation with trimodality therapy (TMT), consisting of transurethral tumor resection followed by chemoradiation, is an alternative to radical cystectomy for muscle-invasive bladder cancer (MIBC), but molecular determinants of response are poorly understood. EXPERIMENTAL DESIGN: We characterized genomic and transcriptomic features correlated with long-term response in a single institution cohort of patients with MIBC homogeneously treated with TMT. Pretreatment tumors from 76 patients with MIBC underwent whole-exome sequencing; 67 underwent matched transcriptomic profiling. Molecular features were correlated with clinical outcomes including modified bladder-intact event-free survival (mBI-EFS), a composite endpoint that reflects long-term cancer control with bladder preservation. RESULTS: With a median follow-up of 74.6 months in alive patients, 37 patients had favorable long-term response to TMT while 39 had unfavorable long-term response. Tumor mutational burden was not associated with outcomes after TMT. DNA damage response gene alterations were associated with improved locoregional control and mBI-EFS. Of these alterations, somatic ERCC2 mutations stood out as significantly associated with favorable long-term outcomes; patients with ERCC2 mutations had significantly improved mBI-EFS [HR, 0.15; 95% confidence interval (CI), 0.06-0.37; P = 0.030] and improved BI-EFS, an endpoint that includes all-cause mortality (HR, 0.33; 95% CI, 0.15-0.68; P = 0.044). ERCC2 mutant bladder cancer cell lines were significantly more sensitive to concurrent cisplatin and radiation treatment in vitro than isogenic ERCC2 wild-type cells. CONCLUSIONS: Our data identify ERCC2 mutation as a candidate biomarker associated with sensitivity and long-term response to chemoradiation in MIBC. These findings warrant validation in independent cohorts.

Sequential intravesical gemcitabine/docetaxel provides a durable remission in recurrent high-risk NMIBC following BCG therapy.

PURPOSE: Bacillus Calmette-Guerin (BCG) is the standard of care for high-risk nonmuscle invasive bladder cancer (NMIBC), but half of patients develop disease recurrence. Intravesical regimens for BCG unresponsive NMIBC are limited. We report the safety, efficacy, and differential response of sequential gemcitabine/docetaxel (gem/doce) depending on BCG failure classification. METHODS: Multi-institutional retrospective analysis of patients treated with induction intravesical gem/doce (≥5/6 instillations) for recurrent high-risk NMIBC after BCG therapy from May 2018 to December 2021. Maintenance therapy was provided to those without high-grade (HG) recurrence on surveillance cystoscopy. Kaplan-Meier curves and Cox regression analyses were utilized to assess survival and risk factors for disease recurrence. RESULTS: Our cohort included 102 patients with BCG-unresponsive NMIBC. Median age was 72 years and median follow-up was 18 months. Six-, 12-, and 24-month high-grade recurrence-free survival was 78%, 65%, and 49%, respectively. Twenty patients underwent radical cystectomy (median 15.5 months from induction). Six patients progressed to muscle invasive disease. Fifty-seven percent of patients experienced mild/moderate adverse effects (AE), but only 6.9% experienced a delay in treatment schedule. Most common AE were urinary frequency/urgency (41%) and dysuria (21%). Patients with BCG refractory disease were more likely to develop HG recurrence when compared to patients with BCG relapsing disease (HR 2.14; 95% CI 1.02-4.49). CONCLUSIONS: In patients with recurrence after BCG therapy, sequential intravesical gem/doce is an effective and well-tolerated alternative to early cystectomy. Patients with BCG relapsing disease are more likely to respond to additional intravesical gem/doce. Further investigation with a prospective trial is imperative.

Radical cystectomy versus trimodality therapy for muscle-invasive bladder cancer: a multi-institutional propensity score matched and weighted analysis.

BACKGROUND: Previous randomised controlled trials comparing bladder preservation with radical cystectomy for muscle-invasive bladder cancer closed due to insufficient accrual. Given that no further trials are foreseen, we aimed to use propensity scores to compare trimodality therapy (maximal transurethral resection of bladder tumour followed by concurrent chemoradiation) with radical cystectomy. METHODS: This retrospective analysis included 722 patients with clinical stage T2-T4N0M0 muscle-invasive urothelial carcinoma of the bladder (440 underwent radical cystectomy, 282 received trimodality therapy) who would have been eligible for both approaches, treated at three university centres in the USA and Canada between Jan 1, 2005, and Dec 31, 2017. All patients had solitary tumours less than 7 cm, no or unilateral hydronephrosis, and no extensive or multifocal carcinoma in situ. The 440 cases of radical cystectomy represent 29% of all radical cystectomies performed during the study period at the contributing institutions. The primary endpoint was metastasis-free survival. Secondary endpoints included overall survival, cancer-specific survival, and disease-free survival. Differences in survival outcomes by treatment were analysed using propensity scores incorporated in propensity score matching (PSM) using logistic regression and 3:1 matching with replacement and inverse probability treatment weighting (IPTW). FINDINGS: In the PSM analysis, the 3:1 matched cohort comprised 1119 patients (837 radical cystectomy, 282 trimodality therapy). After matching, age (71·4 years [IQR 66·0-77·1] for radical cystectomy vs 71·6 years [64·0-78·9] for trimodality therapy), sex (213 [25%] vs 68 [24%] female; 624 [75%] vs 214 [76%] male), cT2 stage (755 [90%] vs 255 [90%]), presence of hydronephrosis (97 [12%] vs 27 [10%]), and receipt of neoadjuvant or adjuvant chemotherapy (492 [59%] vs 159 [56%]) were similar between groups. Median follow-up was 4·38 years (IQR 1·6-6·7) versus 4·88 years (2·8-7·7), respectively. 5-year metastasis-free survival was 74% (95% CI 70-78) for radical cystectomy and 75% (70-80) for trimodality therapy with IPTW and 74% (70-77) and 74% (68-79) with PSM. There was no difference in metastasis-free survival either with IPTW (subdistribution hazard ratio [SHR] 0·89 [95% CI 0·67-1·20]; p=0·40) or PSM (SHR 0·93 [0·71-1·24]; p=0·64). 5-year cancer-specific survival for radical cystectomy versus trimodality therapy was 81% (95% CI 77-85) versus 84% (79-89) with IPTW and 83% (80-86) versus 85% (80-89) with PSM. 5-year disease-free survival was 73% (95% CI 69-77) versus 74% (69-79) with IPTW and 76% (72-80) versus 76% (71-81) with PSM. There were no differences in cancer-specific survival (IPTW: SHR 0·72 [95% CI 0·50-1·04]; p=0·071; PSM: SHR 0·73 [0·52-1·02]; p=0·057) and disease-free survival (IPTW: SHR 0·87 [0·65-1·16]; p=0·35; PSM: SHR 0·88 [0·67-1·16]; p=0·37) between radical cystectomy and trimodality therapy. Overall survival favoured trimodality therapy (IPTW: 66% [95% CI 61-71] vs 73% [68-78]; hazard ratio [HR] 0·70 [95% CI 0·53-0·92]; p=0·010; PSM: 72% [69-75] vs 77% [72-81]; HR 0·75 [0·58-0·97]; p=0·0078). Outcomes for radical cystectomy and trimodality therapy were not statistically different among centres for cancer-specific survival and metastasis-free survival (p=0·22-0·90). Salvage cystectomy was done in 38 (13%) trimodality therapy patients. Pathological stage in the 440 radical cystectomy patients was pT2 in 124 (28%), pT3-4 in 194 (44%), and 114 (26%) node positive. The median number of nodes removed was 39, the soft tissue positive margin rate was 1% (n=5), and the perioperative mortality rate was 2·5% (n=11). INTERPRETATION: This multi-institutional study provides the best evidence to date showing similar oncological outcomes between radical cystectomy and trimodality therapy for select patients with muscle-invasive bladder cancer. These results support that trimodality therapy, in the setting of multidisciplinary shared decision making, should be offered to all suitable candidates with muscle-invasive bladder cancer and not only to patients with significant comorbidities for whom surgery is not an option. FUNDING: Sinai Health Foundation, Princess Margaret Cancer Foundation, Massachusetts General Hospital.

Dissecting the immune suppressive human prostate tumor microenvironment via integrated single-cell and spatial transcriptomic analyses.

The treatment of low-risk primary prostate cancer entails active surveillance only, while high-risk disease requires multimodal treatment including surgery, radiation therapy, and hormonal therapy. Recurrence and development of metastatic disease remains a clinical problem, without a clear understanding of what drives immune escape and tumor progression. Here, we comprehensively describe the tumor microenvironment of localized prostate cancer in comparison with adjacent normal samples and healthy controls. Single-cell RNA sequencing and high-resolution spatial transcriptomic analyses reveal tumor context dependent changes in gene expression. Our data indicate that an immune suppressive tumor microenvironment associates with suppressive myeloid populations and exhausted T-cells, in addition to high stromal angiogenic activity. We infer cell-to-cell relationships from high throughput ligand-receptor interaction measurements within undissociated tissue sections. Our work thus provides a highly detailed and comprehensive resource of the prostate tumor microenvironment as well as tumor-stromal cell interactions.

An Unusual Case of a Scrotal Porocarcinoma and Review of the Literature.

ABSTRACT: Porocarcinomas are rare tumors derived from the acrosyringium and eccrine ducts, which most commonly occur on the lower extremities or head and neck region in older adults. Microscopically, they invariably demonstrate continuity with the epithelium, showing downgrowth of broad anastomosing bands with more infiltrative intradermal cords and nests of pleomorphic tumor cells with ductal lumina; an associated poroma may also be seen. We report an unusual case of a porocarcinoma arising on the scrotum of a 55-year-old man. Because of the extraordinary location and the presence of keratinizing squamous differentiation, distinction from a squamous cell carcinoma was particularly challenging. Close examination revealed the presence of a co-existing poroma, and immunohistochemistry revealed loss of YAP1 with diffuse nuclear expression of NUT in both the porocarcinoma and poroma components. This finding is particularly suggestive of a YAP1::NUTM1 fusion which has been reported to be highly specific for poroid neoplasms. Distinction of porocarcinoma from its mimics is important due to the frequent aggressive behavior of this neoplasm.

Mortality related to the use of stapler devices and clip appliers: Analysis of the Food and Drug Administration Manufacturer and User Facility Device Experience database.

BACKGROUND: Surgical staplers and clip appliers are commonly used and have a potential to malfunction, which may result in serious injury or death. These events are self-reported to the Food and Drug Administration and compiled in the Food and Drug Administration's Manufacturer and User Facility Device Experience database. This study characterizes mortality related to surgical stapler and clip applier failure reported in the Food and Drug Administration's Manufacturer and User Facility Device Experience database. METHODS: The Food and Drug Administration's Manufacturer and User Facility Device Experience database was reviewed between 1992 and 2016 for medical device reports related to surgical staplers and clip appliers filed under the following product codes: GAG, FZP, GDO, GDW, KOG, and GCJ. Adverse events including death and the type of device failure were reviewed. Temporal trends in reported deaths related to device failure were analyzed and the Healthcare Cost and Utilization Project database was used to adjust for annual surgical case volume using linear regression analysis. RESULTS: A total of 75,415 malfunctions, 21,115 injuries, and 676 deaths were associated with the use of surgical stapler and clip applier devices. Most deaths occurred postoperatively (N = 516, 76.3%) and were due to infection/sepsis (N = 89, 17.2%) or vascular injuries (N = 110, 21.3%). Intraoperative mortality (N = 79, 11.7%) was primarily due to vascular injuries (N = 73, 92.4%). Device failures resulting in death were noted both intraoperatively (N = 268, 39.6%) and postoperatively (N = 325, 48.1%). In post hoc root cause analysis, a surgical stapler and clip applier device problem was the most common attributed cause of death (N = 238, 65.4%). In the linear regression analysis, there was a significant increase in the mortality from device failure in the study period after adjusting for annual surgical volume (P < .01). CONCLUSION: Mortality related to the use of surgical staplers and clip appliers is increasing. Most deaths occurred postoperatively, and an increased awareness of potential life-threatening complications is warranted when these devices are used.

Mucinous adenocarcinoma of the prostatic urethra after brachytherapy for prostatic adenocarcinoma: a case series.

Mucinous adenocarcinoma of the urethra is extremely rare, even more so in a setting of postradiation therapy, with only 3 cases reported up to date including the first case published by our group in 2011. In the present study, we included the long-term follow-up on our previously reported case and report 3 additional cases. This is the first case series to date of this rare disease entity. The aim of this study is to review the clinicopathologic features of mucinous adenocarcinoma of the prostatic urethra in patients after receiving brachytherapy for prostatic adenocarcinoma. We identified 4 patients with a mean age of 72 years, and a mean interval of 14.8 years from brachytherapy for prostate carcinoma (grade group 1). Patients presented with hematuria or urinary retention. A colonoscopy was performed in three-fourth of patients and was within normal limits. Three patients underwent cystoprostatectomy and 1 had a transurethral resection of the prostate. On gross examination, only tumor formed a 3.5 cm tan-gray, ulcerated, friable, and necrotic mass and 2 displayed either irregular red granular or thickened areas within the prostatic urethra. Abundant extracellular mucin pools dissecting the prostatic stroma were present in all tumors, with clusters of tumor cells floating in the mucin. The mucin pools were lined by pleomorphic pseudostratified columnar mucinous epithelium. Tumors were diffusely positive for CK20, CDX2 (4/4), and AMACR (2/2); they focally expressed CK7 (2/4), and lacked nuclear ß-catenin expression (3/3). PSA, PSAP, NKX3.1, p63, and GATA3 were negative in the tumors tested. Among the 3 patients who underwent radical surgery, 2 had stage 2 tumors (confined to the prostatic urethra and prostate), and 1 had a stage 3 tumor, with seminal vesicle involvement. All 4 patients were alive without disease with a mean follow-up of 4.9 years. In conclusion, brachytherapy-associated mucinous adenocarcinoma of the prostatic urethra displays intestinal-type features as its non-radiation-related counterpart. It appears to lack a villous adenoma component, displays a different immunohistochemical profile with diffuse CK20 and CDX2 positivity, and is associated with lower stage and less aggressive behavior.

Healthcare Resource Utilization After Surgical Treatment of Cancer: Value of Minimally Invasive Surgery.

BACKGROUND: As the US healthcare system moves towards value-based care, hospitals have increased efforts to improve quality and reduce unnecessary resource use. Surgery is one of the most resource-intensive areas of healthcare and we aim to compare health resource utilization between open and minimally invasive cancer procedures. METHODS: We retrospectively analyzed cancer patients who underwent colon resection, rectal resection, lobectomy, or radical nephrectomy within the Premier hospital database between 2014 and 2019. Study outcomes included length of stay (LOS), discharge status, reoperation, and 30-day readmission. The open surgical approach was compared to minimally invasive approach (MIS), with subgroup analysis of laparoscopic/video-assisted thoracoscopic surgery (LAP/VATS) and robotic (RS) approaches, using inverse probability of treatment weighting. RESULTS: MIS patients had shorter LOS compared to open approach: - 1.87 days for lobectomy, - 1.34 days for colon resection, - 0.47 days for rectal resection, and - 1.21 days for radical nephrectomy (all p < .001). All MIS procedures except for rectal resection are associated with higher discharge to home rates and lower reoperation and readmission rates. Within MIS, robotic approach was further associated with shorter LOS than LAP/VATS: - 0.13 days for lobectomy, - 0.28 days for colon resection, - 0.67 days for rectal resection, and - 0.33 days for radical nephrectomy (all p < .05) and with equivalent readmission rates. CONCLUSION: Our data demonstrate a significant shorter LOS, higher discharge to home rate, and lower rates of reoperation and readmission for MIS as compared to open procedures in patients with lung, kidney, and colorectal cancer. Patients who underwent robotic procedures had further reductions in LOS compare to laparoscopic/video-assisted thoracoscopic approach, while the reductions in LOS did not lead to increased rates of readmission.

Combination MRI-targeted and systematic prostate biopsy may overestimate gleason grade on final surgical pathology and impact risk stratification.

PURPOSE: Gleason grade (GG) on prostate biopsy is important for risk stratification and clinical decision making. Multiparametric MRI (mpMRI) improved detection of clinically significant disease and some studies suggest that MRI-fusion biopsy combined with systematic biopsy results in fewer upgrades on final surgical pathology. However, the downgrade rate is unclear and there is controversy in the literature. The objectives of this study are to assess the concordance of combination biopsy with final surgical pathology, and furthermore, to specifically determine downgrade rates. MATERIALS AND METHODS: In our institutional mpMRI-ultrasound fusion biopsy database, 173 underwent targeted and systematic biopsy followed by radical prostatectomy (RP). GG on targeted, systematic and combination (targeted and systematic) biopsy were compared with GG on RP. Concordance rates between biopsy types were compared with the McNemar test. Proportion of GG upgrade or downgrade at the time of RP was also evaluated. RESULTS: Surgical pathology was concordant with 44.5% of systematic biopsies, 46.8% of targeted biopsies, and 56.7% of combination biopsies. Combination biopsy significantly overestimated the final GG on RP compared to systematic biopsy (16.8% vs. 8.7% RR 1.93, 95% CI 1.36-2.75, P < 0.001). Downgrade rate from unfavorable to favorable intermediate-risk disease was 46.2%, and from high-risk to intermediate-risk disease was 45.1%. CONCLUSIONS: Combination (targeted and systematic) biopsy is associated with the highest concordance rate between biopsy and RP pathology when compared with systematic or targeted biopsy alone. However, targeting MRI lesions and therefore the higher risk components, may at times overestimate the final surgical pathology which can result in overtreatment of what may truly be less aggressive disease.

Complications and Outcomes of Salvage Cystectomy after Trimodality Therapy.

PURPOSE: Salvage cystectomy is required for some patients with intravesical recurrence after trimodality therapy. We compared postoperative outcomes between salvage cystectomy post-trimodality therapy, primary cystectomy and primary cystectomy with prior history of nontrimodality therapy abdominal or pelvic radiotherapy. MATERIALS AND METHODS: We included 265 patients who underwent radical cystectomy at Massachusetts General Hospital for cT1-T4 bladder cancer between 2003 and 2013. Patients were grouped as salvage cystectomy post-trimodality therapy, primary cystectomy or primary cystectomy with prior history of nontrimodality therapy abdominal or pelvic radiotherapy. Early (≤90 days) and late (>90 days) complications were compared. Disease-specific survival and overall survival were calculated using a Cox regression model, and adjusted survival curves were generated. RESULTS: The median followup from the time of cystectomy was 65.5 months. There was no difference in intraoperative and early complications between the groups. The detection of late complications was higher in salvage cystectomy post-trimodality therapy compared to primary cystectomy and primary cystectomy with prior history of nontrimodality therapy abdominal or pelvic radiotherapy (p=0.03). In multivariable Cox regression analysis, salvage cystectomy post-trimodality therapy was associated with a higher incidence of any late (HR 2.3, p=0.02) and major late complications (HR 2.1, p <0.05). There was no difference in disease-specific survival (p=0.8) or overall survival (p=0.9) between the groups. CONCLUSIONS: Salvage cystectomy post-trimodality therapy for intravesical recurrence post-trimodality therapy has an intraoperative and early complication rate comparable to primary cystectomy and primary cystectomy with prior history of nontrimodality therapy abdominal or pelvic radiotherapy. Salvage cystectomy post-trimodality therapy is associated with a higher risk of overall and major late complications than primary cystectomy. The disease-specific survival and overall survival of patients who require salvage cystectomy post-trimodality therapy are comparable to both groups.

TCF21 Promotes Luminal-Like Differentiation and Suppresses Metastasis in Bladder Cancer.

Little is known regarding the subclone evolution process in advanced bladder cancer, particularly with respect to the genomic alterations that lead to the development of metastatic lesions. In this project, we identify gene expression signatures associated with metastatic bladder cancer through mRNA expression profiling of RNA isolated from 33 primary bladder cancer and corresponding lymph node (LN) metastasis samples. Gene expression profiling (GEP) was performed on RNA isolated using the Illumina DASL platform. We identified the developmental transcription factor TCF21 as being significantly higher in primary bladder cancer compared with LN metastasis samples. To elucidate its function in bladder cancer, loss- and gain-of-function experiments were conducted in bladder cancer cell lines with high and low expression of TCF21, respectively. We also performed GEP in bladder cancer cell lines following TCF21 overexpression. We identified 2,390 genes differentially expressed in primary bladder cancer and corresponding LN metastasis pairs at an FDR cutoff of 0.1 and a fold change of 1. Among those significantly altered, expression of TCF21 was higher in the primary tumor compared with LN metastasis. We validated this finding with qPCR and IHC on patient samples. Moreover, TCF21 expression was higher in luminal cell lines and knockdown of TCF21 increased invasion, tumor cell dissemination, and metastasis. In contrast, overexpression of TCF21 in highly metastatic basal bladder cancer cell lines decreased their invasive and metastatic potential. IMPLICATIONS: TCF21 is differentially overexpressed in primary bladder cancer compared with matched LN metastasis, with in vitro and in vivo studies demonstrating a metastasis suppressor function of this transcription factor.

Multiparametric Magnetic Resonance Imaging-Ultrasound Fusion Biopsy Improves but Does Not Replace Standard Template Biopsy for the Detection of Prostate Cancer.

PURPOSE: There exists a growing debate as to whether multiparametric magnetic resonance imaging with fusion transrectal ultrasound guided prostate biopsy alone without a standard template biopsy is sufficient to evaluate patients with suspected prostate cancer. Our objective was to describe our experience with fusion targeted prostate biopsy and assess whether it could obviate the need for concomitant standard 12-core template prostate biopsy. MATERIALS AND METHODS: We retrospectively reviewed our prospectively collected database of patients who underwent fusion transrectal ultrasound guided prostate biopsy. All images and lesions were graded according to the Prostate Imaging Reporting and Data System, version 2. All patients underwent targeted biopsy followed by standard 12-core double sextant biopsy within the same session. Clinically significant prostate cancer was defined as Grade Group 2 or greater prostate cancer. RESULTS: A total of 506 patients were included in analysis. Indications were elevated prostate specific antigen with a previous negative prostate biopsy in 46% of cases, prostate cancer on active surveillance in 35%, elevated prostate specific antigen without a prior prostate biopsy in 15% and an isolated abnormal digital rectal examination in 3%. For standard vs fusion prostate biopsy the overall cancer detection rate was 57.7% vs 54.0% (p=0.12) and the clinically significant prostate cancer detection rate was 24.7% vs 30.8% (p=0.001). Of the 185 patients diagnosed with clinically significant prostate cancer 29 (16%) would have been missed if only targeted fusion prostate biopsy had been performed. CONCLUSIONS: Fusion targeted prostate biopsy is associated with a higher detection rate of clinically significant prostate cancer compared to standard double sextant biopsy. However, standard double sextant biopsy should still be performed as part of the routine fusion targeted prostate biopsy procedure to avoid missing a significant proportion of clinically significant prostate cancer.

PARP-1 inhibition with or without ionizing radiation confers reactive oxygen species-mediated cytotoxicity preferentially to cancer cells with mutant TP53.

Biomarkers and mechanisms of poly (ADP-ribose) polymerase (PARP) inhibitor-mediated cytotoxicity in tumor cells lacking a BRCA-mutant or BRCA-like phenotype are poorly defined. We sought to explore the utility of PARP-1 inhibitor (PARPi) treatment with/without ionizing radiation in muscle-invasive bladder cancer (MIBC), which has poor therapeutic outcomes. We assessed the DNA damaging and cytotoxic effects of the PARPi olaparib in nine bladder cancer cell lines. Olaparib radiosensitized all cell lines with dose enhancement factors from 1.22 to 2.27. Radiosensitization was correlated with the induction of potentially lethal DNA double-strand breaks (DSB) but not with RAD51 foci formation. The ability of olaparib to radiosensitize MIBC cells was linked to the extent of cell kill achieved with the drug alone. Unexpectedly, increased levels of reactive oxygen species (ROS) resulting from PARPi treatment were the cause of DSB throughout the cell cycle in vitro and in vivo. ROS originated from mitochondria and were required for the radiosensitizing effects of olaparib. Consistent with the role of TP53 in ROS regulation, loss of p53 function enhanced radiosensitization by olaparib in non-isogenic and isogenic cell line models and was associated with increased PARP-1 expression in bladder cancer cell lines and tumors. Impairment of ATM in addition to p53 loss resulted in an even more pronounced radiosensitization. In conclusion, ROS suppression by PARP-1 in MIBC is a potential therapeutic target either for PARPi combined with radiation or drug alone treatment. The TP53 and ATM genes, commonly mutated in MIBC and other cancers, are candidate biomarkers of PARPi-mediated radiosensitization.

Incidence, Clinicopathological Risk Factors, Management and Outcomes of Nonmuscle Invasive Recurrence after Complete Response to Trimodality Therapy for Muscle Invasive Bladder Cancer.

PURPOSE: We describe the incidence, clinicopathological risk factors, management and outcomes of recurrent nonmuscle invasive bladder cancer after a complete response to trimodality therapy of muscle invasive bladder cancer. MATERIALS AND METHODS: We retrospectively reviewed the records of 342 patients with cT2-4aN0M0 muscle invasive bladder cancer and a complete response after trimodality therapy from 1986 to 2013. Using competing risks analyses we examined the association between baseline clinicopathological variables and nonmuscle invasive bladder cancer outcomes. Kaplan-Meier and the generalized Fleming-Harrington test were used to compare disease specific and overall survival. RESULTS: At a median followup of 9 years nonmuscle invasive bladder cancer recurred in 85 patients (25%) who had had a complete response. On Kaplan-Meier analysis baseline carcinoma in situ was associated with recurrent nonmuscle invasive bladder cancer (p = 0.02). However, on multivariate analysis carcinoma in situ and other baseline clinicopathological characteristics did not predict such recurrence. Patients with recurrent nonmuscle invasive bladder cancer had worse 10-year disease specific survival than those without recurrence (72.1% vs 78.4%, p = 0.002), although overall survival was similar (p = 0.66). Of the 39 patients (46%) who received adjuvant intravesical bacillus Calmette-Guérin 29 (74%) completed induction therapy and 19 (49%) reported bacillus Calmette-Guérin toxicity. Three-year recurrence-free and progression-free survival after induction bacillus Calmette-Guérin was 59% and 63%, respectively. CONCLUSIONS: After a complete response to trimodality therapy nonmuscle invasive bladder cancer recurred in 25% of patients, developing in some of them more than a decade after trimodality therapy. No baseline clinicopathological characteristics were associated with such recurrence after a complete response. Patients with nonmuscle invasive bladder cancer recurrence had worse disease specific survival than those without such recurrence but similar overall survival. Adjuvant intravesical bacillus Calmette-Guérin had a reasonable toxicity profile and efficacy in this population. Properly selected patients with recurrent nonmuscle invasive bladder cancer after a complete response may avoid immediate salvage cystectomy.

Clinical Outcomes of Patients with Histologic Variants of Urothelial Cancer Treated with Trimodality Bladder-sparing Therapy.

BACKGROUND: Trimodality bladder-sparing therapy (TMT) is an acceptable treatment for selected patients with muscle-invasive urothelial cancer. Outcomes of TMT in histologic variants remains largely unknown. OBJECTIVE: To compare outcomes of pure urothelial carcinoma (PUC) to variant urothelial carcinoma (VUC) after TMT. DESIGN, SETTING, AND PARTICIPANTS: Retrospective study of patients treated with TMT at a single cancer center from 1993 until 2013. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Kaplan-Meier survival probabilities, and univariate and multivariable Cox regression analysis. RESULTS AND LIMITATIONS: Of 303 patients treated with TMT, 66 (22%) had VUC. Fifty (76%) had VUC with squamous and/or glandular differentiation and 16 (24%) had other forms. Complete response rate after induction TMT was 83% in PUC and 82% in VUC (p=0.9). The 5-yr and 10-yr disease-specific survival (DSS) was 75% and 67% in PUC versus 64% and 64% in VUC. The 5-yr and 10-yr overall survival (OS) was 61% and 42% in PUC versus 52% and 42% in VUC. On multivariable analysis VUC was not associated with DSS (hazard ratio: 1.3, 95% confidence interval: 0.8-2.2, p=0.3) or OS (hazard ratio: 1.2, 95% confidence interval: 0.8-1.7, p=0.4). Salvage cystectomy rates were similar (log-rank p=0.3). Limitations include retrospective design and restriction to variants of urothelial cancer. CONCLUSIONS: VUC responded to TMT, and there was no significant difference in complete response, OS, DSS, or salvage cystectomy rates compared with PUC. The presence of VUC should not exclude patients from TMT. PATIENT SUMMARY: The response of histologic variants of bladder cancer to bladder-sparing chemoradiation is largely unknown. We compared the outcomes of histologic variants of urothelial cancer to pure urothelial cancer in a large series of patients from a single institution. We found that variant histology does not significantly influence outcomes.

Long-term Outcomes After Bladder-preserving Tri-modality Therapy for Patients with Muscle-invasive Bladder Cancer: An Updated Analysis of the Massachusetts General Hospital Experience.

BACKGROUND: Tri-modality therapy (TMT) is a recognized treatment strategy for selected patients with muscle-invasive bladder cancer (MIBC). OBJECTIVE: Report long-term outcomes of patients with MIBC treated by TMT. DESIGN, SETTING, AND PARTICIPANTS: Four hundred and seventy-five patients with cT2-T4a MIBC were enrolled on protocols or treated as per protocol at the Massachusetts General Hospital between 1986 and 2013. INTERVENTION: Patients underwent transurethral resection of bladder tumor followed by concurrent radiation and chemotherapy. Patients with less than a complete response (CR) to chemoradiation or with an invasive recurrence were recommended to undergo salvage radical cystectomy. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Disease-specific survival (DSS) and overall survival (OS) were calculated using the Kaplan-Meier method. RESULTS AND LIMITATIONS: Median follow-up for surviving patients was 7.21 yr. Five- and 10-yr DSS rates were 66% and 59%, respectively. Five- and 10-yr OS rates were 57% and 39%, respectively. The risk of salvage cystectomy at 5 yr was 29%. In multivariate analyses, T2 disease (OS hazard ratio [HR]: 0.57, 95% confidence interval [CI]: 0.44-0.75, DSS HR: 0.51, 95% CI: 0.36-0.73), CR to chemoradiation (OS HR: 0.61, 95% CI: 0.46-0.81, DSS HR: 0.49, 95% CI: 0.34-0.71), and presence of tumor-associated carcinoma in situ (OS HR: 1.56, 95% CI: 1.17-2.08, DSS HR: 1.50, 95% CI: 1.03-2.17) were significant predictors for OS and DSS. When evaluating our cohort over treatment eras, rates of CR improved from 66% to 88% and 5-yr DSS improved from 60% to 84% during the eras of 1986-1995 to 2005-2013, while the 5-yr risk of salvage radical cystectomy rate decreased from 42% to 16%. CONCLUSIONS: These data demonstrate high rates of CR and bladder preservation in patients receiving TMT, and confirm DSS rates similar to modern cystectomy series. Contemporary results are particularly encouraging, and therefore TMT should be discussed and offered as a treatment option for selected patients. PATIENT SUMMARY: Tri-modality therapy is an alternative to radical cystectomy for patients with muscle-invasive bladder cancer, and is associated with comparable long-term survival and high rates of bladder preservation.

Employing an orthotopic model to study the role of epithelial-mesenchymal transition in bladder cancer metastasis.

Epithelial-to-mesenchymal transition (EMT) has been implicated in the progression of bladder cancer. To study its contribution to bladder cancer metastasis, we established new xenograft models derived from human bladder cancer cell lines utilizing an orthotopic "recycling" technique that allowed us to isolate and examine the primary tumor and its corresponding circulating tumor cells (CTC's) and metastatic lesions. Using whole genome mRNA expression profiling, we found that a reversible epithelial-to-mesenchymal transition (EMT) characterized by TGFß pathway activation and SNAIL expression was associated with the accumulation of CTCs. Finally, we observed that conditional silencing of SNAIL completely blocked CTC production and regional/distant metastasis. Using this unique bladder cancer xenograft model, we conclude that metastasis is dependent on a reversible EMT mediated by SNAIL.