Diagnostic Laparoscopy and Abdominal Cytology Reliably Detect Peritoneal Metastases in Patients with Urachal Adenocarcinoma.

BACKGROUND: Urachal adenocarcinoma (UrAC) is a rare malignancy that can cause peritoneal metastases (PM). Analogous to other enteric malignancies, selected patients with limited PM of UrAC can be treated by cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS/HIPEC). OBJECTIVE: The aim of this study was to address the value of diagnostic laparoscopy (DLS) and abdominal cytology (ACyt) for the detection and evaluation of the extent of PM in patients with UrAC. METHODS: A consecutive series of cN0M0 patients with UrAC who underwent DLS with or without ACyt at a tertiary referral center between 2000 and 2018 was assessed. Patients were staged with computed tomography (CT) and/or positron emission tomography (PET)/CT or bone scan. DLS was performed to rule out PM and to evaluate the extent and resectability of PM if seen on imaging. Sensitivity and specificity values were calculated for imaging, DLS, ACyt, and the combination of DLS and ACyt. RESULTS: Thirty-two patients with UrAC underwent DLS. ACyt was obtained in 19 patients. Four patients had suspicion of PM on imaging. In the 28 patients who were PM-negative on imaging, DLS and ACyt revealed PM in 6 (21%) patients, of whom 5 had macroscopically visible PM; 1 patient had positive ACyt without visible PM. Sensitivity of combined DLS/ACyt for the detection of PM was 91%, with a specificity of 100%, whereas sensitivity of imaging was 36%. DLS correctly predicted resectability in all patients. CONCLUSION: Combined DLS/ACyt proved an effective tool to detect occult PM and to evaluate the extent of PM to select UrAC patients for possible treatment with CRS/HIPEC.

Long-term survival after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC) for patients with peritoneal metastases of urachal cancer.

INTRODUCTION: Urachal adenocarcinoma (UrAC) is a rare malignancy arising from persistent urachal remnants, which can cause peritoneal metastases (PM). Currently, patients with this stage UrAC are considered beyond cure. Our objective is to report long-term oncological outcome after cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) for patients with PM of urachal adenocarcinoma (UrAC). MATERIALS AND METHODS: We identified 55 patients with UrAC treated at our hospital between 1994 and 2017. Patients were staged with CT, bone scintigraphy and/or PET/CT. From 2001 on, cN0M0 patients underwent staging laparoscopy. Ten patients had PM and were treated with CRS/HIPEC; 35 showed no metastases and underwent local treatment; 10 had distant metastases and received palliative chemotherapy. Disease-specific survival (DSS) rates were estimated using the Kaplan-Meier method and log-rank tests. Postoperative complications represent a secondary outcome. RESULTS: The median follow-up was 96.8 months. Of the CRS/HIPEC patients, 5 (50%) developed a recurrence; 4 (40%) died of disease. The 2-yr and 5-yr DSS after CRS/HIPEC were 66.7% and 55.6%, respectively. DSS of the CRS/HIPEC patients did not significantly differ from DSS of patients without metastases who only underwent curative local treatment and was superior to patients with distant metastases (P = 0.012). The overall complication rate after CRS/HIPEC was 60%. Major complications (Clavien 3) constituted 20%. The study is limited by its retrospective nature and the small sample size. CONCLUSION: CRS/HIPEC demonstrates satisfactory long-term oncological outcome for patients with PM of UrAC. It may be offered as a potentially curative treatment option for this group of patients.

Pathogenic and targetable genetic alterations in 70 urachal adenocarcinomas.

Urachal cancer (UrC) is a rare but aggressive malignancy often diagnosed in advanced stages requiring systemic treatment. Although cytotoxic chemotherapy is of limited effectiveness, prospective clinical studies can hardly be conducted. Targeted therapeutic treatment approaches and potentially immunotherapy based on a biological rationale may provide an alternative strategy. We therefore subjected 70 urachal adenocarcinomas to targeted next-generation sequencing, conducted in situ and immunohistochemical analyses (including PD-L1 and DNA mismatch repair proteins [MMR]) and evaluated the microsatellite instability (MSI) status. The analytical findings were correlated with clinicopathological and outcome data and Kaplan-Meier and univariable/multivariable Cox regression analyses were performed. The patients had a mean age of 50 years, 66% were male and a 5-year overall survival (OS) of 58% and recurrence-free survival (RFS) of 45% was detected. Sequence variations were observed in TP53 (66%), KRAS (21%), BRAF (4%), PIK3CA (4%), FGFR1 (1%), MET (1%), NRAS (1%), and PDGFRA (1%). Gene amplifications were found in EGFR (5%), ERBB2 (2%), and MET (2%). We detected no evidence of MMR-deficiency (MMR-d)/MSI-high (MSI-h), whereas 10 of 63 cases (16%) expressed PD-L1. Therefore, anti-PD-1/PD-L1 immunotherapy approaches might be tested in UrC. Importantly, we found aberrations in intracellular signal transduction pathways (RAS/RAF/PI3K) in 31% of UrCs with potential implications for anti-EGFR therapy. Less frequent potentially actionable genetic alterations were additionally detected in ERBB2 (HER2), MET, FGFR1, and PDGFRA. The molecular profile strengthens the notion that UrC is a distinct entity on the genomic level with closer resemblance to colorectal than to bladder cancer.

Genetics and biological markers in urachal cancer.

Urachal cancer (UraC) is a rare tumor entity that usually develops at the basis of the remnant embryologic urachus. Consisting of mostly adenocarcinomas, most patients present with secondary symptoms due to an advanced stage with urinary bladder infiltration. One third of patients are already metastasized at presentation rendering them unsuitable for curative surgical treatment. In order to improve staging, treatment and follow-up, adequate knowledge about the genetic origin and potential markers is necessary. This paper reviews the English literature until December 2015. Pathologists argue for and against metaplasia or remnant enteric cells as origin for the adenomatous tissue found in UraC. Mutations in KRAS, BRAF, GNAS and Her2 have been associated with UraC. Immunohistochemical (IHC) markers like CEA, 34ßE12, Claudin-18 and RegIV are indicative for mucous producing UraC. So far, IHC markers fail as prognosticators when matched to clinical data. Little is known about serum markers for UraC. CEA, CA19-9, CA125 and CA724 are mentioned as being elevated in UraC by some reports. Regarding the literature for biological markers in UraC, knowledge is mostly derived from case reports or cohort studies mentioning markers or predictors. More genetic research is needed to show whether UraC stems from progenitor cells of the cloaca or is due to metaplasia of transitional cells. Few IHC markers have shown indicative potential for UraC. A useful panel for differential diagnostics and clinicopathologic prognostication needs to be developed. Serum markers show very little potential for neither diagnosis nor follow-up in UraC. Further research on larger cohorts is necessary.

Urachal cancer: contemporary review of the pathological, surgical, and prognostic aspects of this rare disease.

Surgery is the mainstay of treatment for patients with urachal cancer (UraC). Still, one third of patients are un-resectable at presentation. Histology shows adenocarcinomas in the majority of cases with resemblance to enteric tumors. Standard chemotherapeutic regimens for bladder cancer have failed these patients. The role and efficacy of radiotherapy remains unclear due to its use in combination with chemotherapy or in a palliative setting. A lack of background knowledge about this disease leaves practitioners with unanswered questions when recommending (neo)adjuvant or palliative treatment options. Despite the lack of large multicenter series or randomized studies, independent case series have found commonalities with gastric, colorectal or ovarian cancers. Better clinical staging, advanced surgical techniques and a variety of (neo)adjuvant therapy combinations spawn hope for improved survival for these patients. Genetic and immunohistochemical studies are debating a common origin of this disease. Meta-analyses of clinical data are showing prognosticators and risk factors. UraC is a rare disease characterized by malignant degeneration of the urachal remnant with the highest incidence in fifty to sixty year old individuals. Unlike bladder cancer, the majority of UraC cases are adenocarcinomas. Its classical location at the bladder dome, advanced stage at presentation and symptoms like hematuria and mucinuria, should make the clinician suspicious. It is important to look for metastases or mucous cysts during clinical staging to determine the possibility of a curative approach. Up to date, surgery including on-bloc resection of the urachal ligament, the bladder dome and the umbilicus is the only proven cure. R0 resection is crucial for recurrence free survival. Adjuvant or palliative therapy can prolong survival in un-resectable or recurrent disease. While curative patients have a survival well above 50% over five years, palliative patients average only two years. Scientific knowledge about UraC is comprised of single center experiences, small collected cohorts or pathology/cancer registry database searches. Many questions like validated staging, (neo)adjuvant treatment options, differences in outcome for different tumor types and the existence of a common genetic origin are still unanswered. Future studies and trials are needed to address these important topics.

Prognostic significance of substage and WHO classification systems in T1 urothelial carcinoma of the bladder.

PURPOSE OF REVIEW: Treatment of T1 urothelial bladder cancer (T1-BC) is challenging as risk assessment criteria for progression are lacking. Histological grade and T1 substage have been identified as important prognostic factors. Currently, no consensus exists regarding the optimal sub-staging and grading systems for T1-BC. We reviewed recent advances in the various grading and sub-staging systems and their clinical applicability. RECENT FINDINGS: Stratification by muscularis mucosae invasion is the most explored sub-staging system. Its prognostic value was established by 12/23 (52%) available studies. Importantly, muscularis mucosae identification varied substantially among pathologists. Sub-staging based on diameter of invasive carcinoma [T1 microinvasive and T1 extensive-invasive (T1m/e)] proved a more reproducible system with at least equal prognostic value. However, more study is needed to investigate interobserver variation. For nonmuscle-invasive bladder cancer grading, the 1973 and 2004 WHO classifications both provide independent prognostic information. However, remarkably few studies have investigated their applicability in T1-BC only. The available reports suggest that the 1973 WHO classification is superior to WHO 2004. SUMMARY: If multicenter studies confirm the promising results of T1m/e sub-staging, it may be incorporated in the Internation Union Against Cancer TNM classification system for urinary bladder cancer. More studies are warranted to define the optimal classification system for grade in T1-BC.