Glandular Tumors of the Urachus and Urinary Bladder: A Practical Overview of a Broad Differential Diagnosis

Acute Glomerulonephritis as a Paraneoplastic Syndrome Secondary to Urachal Adenocarcinoma: An Unknown Entity

Urachal carcinoma is an uncommon malignancy with a peculiar biomolecular characterization and therefore a complex approach. It was incorporated by the World Health Organization in 2004 in the tumors of the urinary system classification. This neoplasm is generally diagnosed in advanced stages. The standard treatment is surgical, however, due to the rarity and relatively late clinical manifestation of urachal carcinomas, the survival data are mostly case reports, as well as information about medical-surgical treatment based on evidence. The data used were extracted from both the physical and electronic clinical records. Among atypical presentations reported in the literature, we report a case of urachal adenocarcinoma with simultaneous glomerulonephritis as a paraneoplastic syndrome of which there is no report to date. Surgery was carried out in our patient, unfortunately with lifetime morbidity from kidney function replacement secondary to kidney function damage by glomerulonephritis, despite previous immunosuppression treatment for rapidly progressive glomerulonephritis. It is worth mentioning that if the initial diagnosis represents a clinical challenge, treatment is even more complex, given the little information that currently exists about it. Urachal carcinoma is a diagnostic and treatment challenge. Up to now, surgery has been the treatment of choice in localized or locally advanced disease, however, with a high morbidity for the patient.

Urothelial Carcinoma: Divergent Differentiation and Morphologic Subtypes

Urothelial carcinoma (UC) is known to encompass a wide spectrum of morphologic features and molecular alterations. Approximately 15% to 25% of invasive UC exhibits histomorphologic features in the form of "divergent differentiation" along other epithelial lineages, or different "subtypes" of urothelial or sarcomatoid differentiation. It is recommended that the percentage of divergent differentiation and or subtype(s) be reported whenever possible. Recent advances in molecular biology have led to a better understanding of the molecular underpinning of these morphologic variations. In this review, we highlight histologic characteristics of the divergent differentiation and subtypes recognized by the latest version of WHO classification, with updates on their molecular and clinical features.

An Unusual Location for a Nonurachal Bladder Adenocarcinoma

Malignant bladder neoplasms represent a significant disease burden not only for urologists but also the broader medical community. While the majority of bladder tumors are urothelial in origin, up to two percent are found to be adenocarcinomas. Among bladder adenocarcinomas, roughly one-tenth are urachal and are frequently located at the dome of the bladder where urachal remnants can often be found. We describe a case of bladder adenocarcinoma that presented at the dome of the bladder but ultimately exhibited a nonurachal histology. A 65-year-old male with a history of myocardial infarction and cerebrovascular accident with residual right-sided hemiparesis and aphasia was referred to our clinic for evaluation of a bladder mass discovered in the setting of painless gross hematuria. Diagnostic cystoscopy demonstrated a large mass at the dome of the bladder, and subsequent transurethral resection revealed stage T1 mucinous adenocarcinoma arising in a villous adenomatous lesion without the presence of muscle in the specimen. The patient underwent a robotic-assisted laparoscopic partial cystectomy with extended bilateral pelvic lymph node dissection. Postoperatively, the patient experienced short-lived paralytic ileus and was discharged on postoperative day 5. Follow-up surveillance imaging at 6 months with CT chest, abdomen, and pelvis, repeat office cystoscopy, and negative tumor markers postoperatively indicated no evidence of disease recurrence. Characterization of bladder adenocarcinomas into urachal and nonurachal subtypes is critical in differentiating the operative management and oncologic outcomes of the respective neoplasms. However, given the paucity of literature describing treatment approaches to bladder adenocarcinoma in general, existing methods have largely mirrored genetically similar neoplasms, including ovarian and colon adenocarcinomas. Although there is still much to be understood regarding the potential mechanisms of carcinogenesis of nonurachal adenocarcinomas, further investigation may pave the way for a more standardized treatment paradigm and provide insight into the potential utility of modern immunotherapies.

[S2k guidelines for the diagnosis and treatment of endometriosis-Recommendations for pathology]

Die vorliegende Übersicht fasst die relevanten Aspekte der S2k-Leitlinie Endometriose zusammen. Die Empfehlungen umfassen die Aufarbeitung und Befunderhebung bei Biopsien und Resektaten, die bei der klinischen Diagnose einer Endometriose entnommen wurden. Die Leitlinie berücksichtigt neben praktischen Aspekten der Pathologie ebenso die klinischen Notwendigkeiten an die Histopathologie für eine optimale Diagnostik und Therapie der Patientinnen.

Basierend auf der in der pathologischen Literatur gebräuchlichsten Definition der Endometriose des Corpus uteri (Adenomyosis uteri) wurde diese in der Leitlinie definiert als der Nachweis des Endometrioseherdes im Myometrium in einem Abstand zur endomyometranen Grenze von einem mittelgroßen Gesichtsfeld (100fache Vergrößerung), was metrisch rund 2,5 mm entspricht. Bei Darmresektaten soll zum Status der Resektionsränder Stellung genommen werden.

Ebenso definiert werden Anforderungen im Kontext endometrioseassoziierter Karzinome (z. B. Hormonrezeptorbestimmungen, immunhistochemische Untersuchung auf Ausfall der DNA-Mismatch-Reparaturproteine).

Clinical, Pathological, and Prognostic Analysis of Urachal Carcinoma

OBJECTIVE

The aim of this study was to improve understanding the clinical, pathologic, and prognostic features of urachal carcinoma (UrC), a retrospectively descriptive study was done in 2 clinical centers.

METHODS

After excluding the 2 missed patients, the clinical and pathological data of 59 patients with UrC, who were diagnosed or treated at 2 clinical centers between 1986 and 2019, was retrospectively analyzed. SPSS 22.0 (IBM) and GraphPad Prism 8.0.1 were used for statistics and data visualization. Survival data were analyzed by the Kaplan-Meier method and Log-rank tests. Cox proportional hazards regression were performed for find risk factors on predicting the prognosis.

RESULTS

Of all 59 patients, 47 were male and 12 were female. The median age at diagnosis was 51.6 years (range: 22-84 years). Gross hematuria was the most common symptom (79.66%). The majority of urachal neoplasms were adenocarcinomas (94.92%). Forty-two patients (72.41%) underwent extended partial cystectomy with en bloc resection of the entire urachus. The mean follow-up was 52 months (3-277 months). Median overall survival was 52.8 months (4-93 months). The 3-year cancer-specific survival (CSS) rate and 5-year CSS rate were 69.1% and 61.2%. There was no significant difference among localized T stage, tumor histologic grade and surgical procedures in determining prognosis by survival analyze. While patients with high-risk TNM stage (local abdominal metastasis, lymph node metastasis, or distant metastasis) (p = 0.003) and positive surgical margin (p < 0.001) had significantly worse prognosis.

CONCLUSIONS

The results indicate that high-risk TNM stage and positive surgical margin are risk predictors of prognosis. Localized T stage, histologic grade, and surgical procedure cause no significant effect on patient prognosis. The extended partial cystectomy is the recommended surgical approach for patients with UrC. Active multimodal treatments may improve the survival of patients with recurrent and metastatic disease.

Comparative genomic profiling of glandular bladder tumours

Primary glandular bladder tumours (bladder adenocarcinoma [BAC], urachal adenocarcinoma [UAC], urothelial carcinoma with glandular differentiation [UCg]) are rare malignancies with histological resemblance to colorectal adenocarcinoma (CORAD) in the majority of this subgroup. Definite case numbers are very low, molecular data are limited and the pathogenesis remains poorly understood. Therefore, this study was designed to complement current knowledge by in depth analysis of BAC (n = 12), UAC (n = 13), UCg (n = 11) and non-invasive glandular lesions (n = 19). In BAC, in addition to known alterations in TP53, Wnt, MAP kinase and MTOR pathway, mutations in SMAD4, ARID1A and BRAF were identified. Compared to published data on muscle invasive bladder cancer (BLCA) and CORAD, UCg exhibited frequent "urothelial" like alterations while BAC and UAC were characterised by a more "colorectal" like mutational pattern. Immunohistochemically, there was no evidence of DNA mismatch repair deficiency or PD-L1 tumour cell positivity in any sample. Depending on the used antibody 0-45% of BAC, 0-30% of UCg and 0% UAC cases exhibited PD-L1 expressing tumour associated immune cells. A single BAC (9%, 1/11) showed evidence of ARID1A protein loss, and two cases of UCg (20%, 2/10) showed loss of SMARCA1 and PBRM1, respectively. Taken together, our data suggest at least in part involvement of similar pathways driving tumourigenesis of adenocarcinomas like BAC, UAC and CORAD independent of their tissue origin. Alterations of TERT and FBXW7 in single cases of intestinal metaplasia further point towards a possible precancerous character in line with previous reports.

Molecular Genetic Features of Primary Nonurachal Enteric-type Adenocarcinoma, Urachal Adenocarcinoma, Mucinous Adenocarcinoma, and Intestinal Metaplasia/Adenoma: Review of the Literature and Next-generation Sequencing Study

The diagnosis of primary adenocarcinoma of the urinary bladder may be challenging in routine practice. These tumors may morphologically and immunohistochemically overlap with urachal adenocarcinoma and colorectal adenocarcinoma. Further, their genetic background is poorly understood. We systematically searched the PubMed database for results of complex genetic evaluation of primary bladder adenocarcinoma subtypes. Subsequently, we designed our own series of bladder lesions. We evaluated 36 cases: 16 primary enteric-type adenocarcinomas, 7 urachal enteric adenocarcinomas, 3 primary mucinous/colloid adenocarcinomas, and 10 intestinal-type metaplasia/villous adenoma. Detailed clinical data were collected, and all cases were examined using targeted next-generation sequencing. On the basis of the literature, the first mutated gene in these tumors was reported to be KRAS in 11.3% of cases, followed by TERT promoter mutations in 28.5%. In addition to KRAS and TERT, other genes were also found to be frequently mutated in primary bladder adenocarcinoma, including TP53, PIK3CA, CTNNB1, APC, FBXW7, IDH2, and RB1. In our series, the most frequent gene mutations in primary enteric-type adenocarcinomas were as follows: TP53 (56%); BRCA2, KMT2B (both 33%); NOTCH2, KDR, ARID1B, POLE, PTEN, KRAS (all 28%); in urachal enteric adenocarcinoma they were as follows: TP53 (86%); PTEN, NOTCH (both 43%); in primary mucinous/colloid adenocarcinomas they were as follows: KRAS, GRIN2A, AURKB (all 67%); and, in intestinal-type metaplasia/villous adenoma, they were as follows: APC, PRKDC (both 60%); ROS1, ATM, KMT2D (all 50%). No specific mutational pattern was identified using cluster analysis for any of the groups. Herein, we describe the pathologic features and immunohistochemical staining patterns traditionally used in the differential diagnoses of glandular lesions of the bladder in routine surgical pathology. We outline the mutational landscape of these lesions as an aggregate of published data with additional data from our cohort. Although diagnostically not discriminatory, we document that the most common genetic alterations shared between these glandular neoplasms include TP53, APC (in the Wnt pathway), and KRAS (in the MAPK pathway) mutations.