Clinical significance of urothelial carcinoma ambiguous for muscularis propria invasion on initial transurethral resection of bladder tumor.

PURPOSE: To evaluate the clinical significance of invasive urothelial carcinoma that is ambiguous for muscularis propria invasion on initial transurethral resection of bladder tumor (TURBT). METHODS: All consecutive in-house TURBTs with invasive urothelial carcinoma from 1999 to 2017 that underwent radical cystectomy (RC) were grouped as follows: invasion of the lamina propria (INLP; n = 102; 24%), invasion of muscularis propria (INMP; n = 296; 69%) and ambiguous for muscularis propria invasion (AMP; n = 30; 7%). AMP was defined as extensive invasive carcinoma displaying thin muscle bundles where it is difficult to determine with certainty if those muscle bundles represent muscularis mucosae or muscularis propria (detrusor). Cases with any amount of small cell carcinoma or prior therapy were excluded. RESULTS: The average age was 66 years in INLP, 67 years in INMP, and 65 years in AMP. RC showed invasive carcinoma stage pT2 or above in 50/102 (49%) of INLP vs. 255/296 (86%) of INMP (P ≤ 001) vs. 25/30 (83.33%) of AMP (P = 0.002). Lymph nodes showed metastatic carcinoma in 18/98 (18.36%) of INLP vs. 96/272 (35.29%) of INMP (P = 0.002), and 6/25 (24%) in AMP (P = 0.729). The average follow-up was 48 months (range 0-192). Survival of AMP patients was similar to INLP and both were significantly better than INMP (P = 0.002 and P = 0.016). CONCLUSION: The great majority of patients with AMP on initial TURBT have advanced disease on RC and emphasizes the need for early repeat TURBT or even consideration of early cystectomy to lower the risk of worse pathological findings and to prolong survival.

Molecular characterization of adenocarcinomas arising in the urinary bladder following augmentation cystoplasty: a multi-institutional study.

Development of malignancy is a rare complication following augmentation cystoplasty, and the majority of tumors observed in this setting are adenocarcinomas. Here, we sought to genetically profile these tumors by targeted DNA sequencing of a multi-institutional cohort of adenocarcinomas that developed in the urinary bladder following augmentation cystoplasty. Carcinomas arising in the urinary bladder of patients with history of augmentation cystoplasty were obtained from 4 major academic institutions, with cases diagnosed as urothelial carcinoma excluded from the study. The cases were analyzed using a DNA sequencing panel that includes 529 genes and genome-wide copy number assessment. The most frequently altered genes included TP53, KRAS, and MYC, and the vast majority of cases demonstrated mutational profiles consistent with gastrointestinal adenocarcinomas. One case demonstrated an EML4::ALK fusion together with an MSH3 frameshift mutation and hypermutated phenotype, characteristic of a rare but aggressive subtype of colorectal adenocarcinoma that may benefit from targeted ALK inhibition therapy. Importantly, six other tumors in the cohort also had potentially targetable molecular alterations, involving ATM (2 cases), BRCA1 (2 cases), EGFR (1 case), and ERBB2 (1 case). To our knowledge, this study represents the most comprehensive molecular characterization to date of adenocarcinomas arising in the urinary bladder following augmentation cystoplasty. Despite the unique environment of the augmented tissue, the resulting tumors demonstrate a spectrum of driver mutations similar to that of primary gastrointestinal adenocarcinomas. Importantly, molecular alterations potentially amenable to targeted therapy were identified in the majority of cases.

Invasive poorly differentiated adenocarcinoma of the bladder following augmentation cystoplasty: a multi-institutional clinicopathological study.

Augmentation cystoplasty is a surgical procedure used in the management of patients with neurogenic bladder. This procedure involves anastomosis of the bladder with gastrointestinal grafts, including portions of ileum, colon, or stomach. A rare but important complication of augmentation cystoplasty is the development of malignancy. The majority of malignancies arising in this setting have been described in case reports. A search for cases of non-urothelial carcinoma following augmentation cystoplasty was conducted through the urological pathology files of four major academic institutions. Ten cases were identified, including six cystoprostatectomy/cystectomy, two partial cystectomy, and two transurethral resection of bladder tumour specimens. The mean patient age at diagnosis was 47 years (range 27-87 years). The male:female ratio was 4:6. The tumours tended to present at an advanced stage; four cystoprostatectomy/cystectomy cases were categorised as pT3a, one was categorised as pT3b, and one was categorised as pT4a. Lymph node metastases were present in all cases which had lymph node excision (range 1-16 positive nodes per case). The majority of cases (90%) were predominantly characterised by a poorly differentiated adenocarcinoma with signet ring cell features. Other morphological features included mucinous features (30%), plasmacytoid features (20%), enteric/villous architecture (10%), and large cell undifferentiated morphology (10%). This is the largest study to date on the clinicopathological features of invasive non-urothelial carcinoma of the bladder following augmentation cystoplasty. The tumours are typically poorly differentiated adenocarcinoma, with diffuse signet ring cell features, aggressive, and present at high stage. Further molecular characterisation may provide additional insights into the pathogenesis of this entity.

Urothelial Carcinoma In Situ of the Bladder: Correlation of CK20 Expression With Adaptive Immune Resistance, Response to BCG Therapy, and Clinical Outcome.

Immunohistochemical stains have been suggested to aid in diagnostically challenging cases of urothelial carcinoma in-situ (CIS). Although full thickness immunostaining for CK20 is supportive of CIS, a subset of CIS cases is CK20(-), the clinical significance of which was unknown. This study included 43 patients with primary diagnosis of bladder CIS including 32 with only CIS, 5 with CIS and separate noninvasive high-grade papillary urothelial carcinoma, and 6 with CIS and separate high-grade urothelial carcinoma with lamina propria invasion. Digital morphometric image analysis showed that the average nuclear areas of enlarged nuclei were similar in CK20(+) and CK20(-) CIS (26.9 vs. 24.5 µM2; P=0.31). Average Ki67 index for CK20(+) CIS was higher than CK20(-) CIS (31.1% vs. 18.3%; P=0.03). Patients with CK20(+) CIS [28 (65%)] and patients with CK20(-) CIS [15 (35%)] had the same rates of Bacillus Calmete-Guerin (BCG) failure but patients with CK20(-) CIS had higher stage progression [3 CK20(+) (11%) vs. 6 CK20(-) (40%); P=0.02]. Given recent approval of immune checkpoint inhibitors in patients with CIS refractory to BCG, programmed death ligand-1 expression and colocalization with CD8(+) lymphocytes was investigated as signature of adaptive immune response and was seen in 8 patients regardless of CK20 status and exclusively among patients who failed BCG. Our results confirm that negative CK20 IHC does not exclude CIS and that those patients have similar clinical outcomes as patients with CK20(+) CIS. Programmed death ligand-1 and CD8 colocalization seen among patients who failed BCG therapy is an easy assay to perform to identify patients who could potentially benefit from combined BCG therapy and immune checkpoint inhibition.

Extramammary Paget Disease of the Scrotum: A Contemporary Clinicopathologic Analysis of 20 Cases in the United States.

Extramammary Paget disease (EMPD) often involves apocrine gland-bearing locations including vulva and perianal area. EMPD of the scrotum is rare. Twenty patients were identified from the pathology files of 4 institutions between 2000 and 2018. Patients were 63- to 87-year-old (mean: 73 y) with a history of symptoms of between 4 months and 10 years. Two patients had a history of prostate cancer. Follow-up was available in 11 patients for a median of 71 months (range: 8 to 126 mo). Nine of 11 patients (82%) had positive margins, and 73% required reexcisions. Three patients had a focal dermal invasion, 1 of whom reportedly died of another etiology 25 months post diagnosis and 2 were disease-free at 24 and 68 months. No patient had inguinal lymphadenopathy. Two patients were alive with disease. Immunohistochemically, GATA3 and GCDFP15 were expressed in 6/6 cases, CK7 in 8/8 cases, and androgen receptor in 13/13 cases. HER2 was positive in 5/12 cases. PSA was positive in 1 patient who had a history of prostate cancer, whereas other prostate markers (NKX3.1 and prostein) were negative, and CK7 and GCDFP15 were positive, rendering primary EMPD diagnosis. Twelve other cases were negative for PSA and NKX3.1. In conclusion, EMPD of the scrotum has an insidious onset and its nonspecific symptoms can be misdiagnosed as dermatitis or fungal infection. Although localized EMPD has a favorable prognosis, the invasive disease is rare and did not predict metastasis or progression. Margins are frequently positive requiring reexcision. Occasionally, cases can be positive for PSA leading to diagnostic pitfalls.

Analysis of Intestinal Metaplasia Without Dysplasia in the Urinary Bladder Reveal Only Rare Mutations Associated With Colorectal Adenocarcinoma.

Intestinal metaplasia (IM) is a rare finding in urinary bladder specimens. It is unclear whether IM without dysplasia is a precursor of malignancy in the urinary system. We retrospectively selected 9 cases of IM of bladder (1 case harboring high-grade dysplasia), and performed mutation analysis for genes frequently mutated in colon cancer including BRAF, APC, KRAS, MET, NRAS, PIK3CA, CTNNB1, FBXW7, and TP53 using validated clinical tests. Control groups included 7 colonic tubular adenomas, 10 high-grade papillary urothelial carcinomas. One IM case revealed an APC mutation and another showed an NRAS mutation. Among the tubular adenomas cases, 6 of 7 (85.7%) harbored KRAS mutations and 3 of 7 (42%) APC mutations. Among urothelial carcinomas cases, 1 revealed a KRAS mutation, 2 had PIK3CA mutations, and all cases were negative for APC mutations. Clinical follow-up for the IM patients was available with a median follow-up of 70 months. One patient-without any mutation in the genes investigated-developed invasive bladder adenocarcinoma with intestinal differentiation with metastasis to the liver and lung. Neither of the 2 patients harboring mutations developed any malignancy. In conclusion, a minority of cases with IM without dysplasia bear mutations in the genes commonly associated with colonic adenocarcinoma, suggesting a premalignant potential for such lesions possibly following the classic multistep chromosomal instability pathway of carcinogenesis. A larger cohort of patients with longer follow-up is needed to better establish whether close follow-up is warranted for mutation-harboring IM of the bladder.

Diagnosis of urothelial carcinoma in situ using blue light cystoscopy and the utility of immunohistochemistry in blue light-positive lesions diagnosed as atypical.

Carcinoma in situ (CIS) is difficult to visualize with white light cystoscopy (WLC), whereas blue light cystoscopy (BLC) using photosensitizing agents improves detection rates. We retrospectively reviewed transurethral biopsies of bladder tumors in which both WLC and BLC evaluations were performed (n = 135 samples from 79 patients). Biopsies were classified based on the presence/absence of fluorescence under BLC and the final pathological report (CIS/benign/atypical). Forty-one (30%) cases were diagnosed as CIS; of those, 38 (93%) were BLC(+), including 23 that were WLC(-). Conversely, 51 (38%) lesions were BLC(+) but classified as non-CIS. Eleven BLC(+) cases were diagnosed as "atypical." These cases were anonymized and reviewed by 7 pathologists for concordance and then immunostained for CK20, p53, and Ki-67. Immunohistochemistry results were interpreted as consistent with CIS if there was full-thickness staining of CK20, more than 50% p53-positive cells, and more than 50% Ki-67-positive cells. Review of BLC(+)/atypical cases showed a mean agreement of 79%, and none of the cases showed staining pattern consistent with CIS. Therefore, all 11 cases of BLC(+)/atypical were considered non-CIS for the final analysis. All patients with BLC(+)/atypical lesions had a history of intravesical Bacillus Calmette-Guerin and/or mitomycin. Using final pathology as the reference, sensitivity, specificity, and negative predictive value of BLC were 93% (confidence interval [CI], 80.1%-98.5%), 46% (CI, 35.4%-56.3%), and 94% (CI, 82.5%-97.8%), respectively. The low specificity of BLC leads to BLC(+) lesions with atypical diagnosis. Morphological classification of these lesions is fairly consistent among different pathologists. Immunohistochemistry for p53/CK20/Ki-67 in this setting is only helpful to potentially avoid overcalling CIS.