Computed tomographic appearance of urachal carcinoma associated with urachal diverticulum misdiagnosed by cystoscopy

Primary urachal leiomyosarcoma: a case report and literature review of clinical, pathological, and medical imaging features

Background

Urachal tumors are exceedingly rare, and adenocarcinoma is the most common malignant urachal neoplasm. Here, an especially rare patient of primary urachal leiomyosarcoma from our hospital was reported, and only five patients have been reported thus far since 1981.

Case description

A 24-year-old man was admitted due to urinary tract symptoms. Both urogenital ultrasonography and contrast-enhanced computed tomography showed a mass at the dome of the urinary bladder. Laparoscopic surgical resection was performed, and histopathologic examination of the mass confirmed the diagnosis of urachal leiomyosarcoma. No recurrence was noted after one and a half years.

Conclusions

Because the leiomyosarcoma located in the extraperitoneal space of Retzius and may manifest with nonspecific abdominal or urinary symptoms, early and definitive preoperative diagnosis is challenging. Partial cystectomy with complete excision of the urachus is recommended. Because only a few patients have been recorded, clinical outcomes and recurrence risks are difficult to assess.

Imaging of urachal anomalies

Urachal anomalies are classified into four types depending on the level of persistence of the embryonic urachal remnants between the urinary bladder and the umbilicus: patent urachus, umbilical-urachal sinus, urachal cyst, and vesico-urachal diverticulum. Due to the increasing use of cross-sectional imaging, urachal anomalies are frequently detected as incidental findings. Imaging plays a pivotal role in the initial diagnosis, evaluation of complications, treatment follow-up, and long-term surveillance of patients with urachal anomalies. Different urachal anomalies demonstrate characteristic imaging features that aid in a timely diagnosis and guide treatment. A patent urachus is visualized as an elongated tubular structure between the umbilicus and the urinary bladder. While umbilical-urachal sinus appears as focal dilatation at the umbilical end of the urachal remnant, the vesico-urachal diverticulum presents as a focal outpouching of the urinary bladder at anterosuperior aspect. Urachal cysts are identified as midline fluid-filled sacs most frequently located near the dome of the urinary bladder. Untreated urachal anomalies could progress into potential complications, including infection and malignancy. Knowledge regarding imaging features of urachal anomalies helps in timely diagnosis, treatment, follow-up, and early detection of complications.

Infection of Previously Closed Urachus Mimicking Malignancy: A Case Report and Literature Review of Radiological Findings to the Diagnosis

The urachus is a vestigial structure of the allantois and cloaca. It involutes as fetal development progresses to become a fibrous cord, which courses between the umbilicus and bladder dome within the retropubic space. Infection occasionally occurs in patients with congenital patent urachus. Here, we report a patient with infection of a previously closed urachal tract presenting as an abdominal mass. This has rarely been described in the literature. Current knowledge on imaging findings to the diagnosis is discussed.

Biomarkers in Urachal Cancer and Adenocarcinomas in the Bladder: A Comprehensive Review Supplemented by Own Data

Urachal cancer (UrC) is a rare but aggressive cancer. Due to overlapping histomorphology, discrimination of urachal from primary bladder adenocarcinomas (PBAC) and adenocarcinomas secondarily involving the bladder (particularly colorectal adenocarcinomas, CRC) can be challenging. Therefore, we aimed to give an overview of helpful (immunohistochemical) biomarkers and clinicopathological factors in addition to survival analyses and included institutional data from 12 urachal adenocarcinomas. A PubMed search yielded 319 suitable studies since 1930 in the English literature with 1984 cases of UrC including 1834 adenocarcinomas (92%) and 150 nonadenocarcinomas (8%). UrC was more common in men (63%), showed a median age at diagnosis of 50.8 years and a median tumor size of 6.0 cm. No associations were noted for overall survival and progression-free survival (PFS) and clinicopathological factors beside a favorable PFS in male patients (p = 0.047). The immunohistochemical markers found to be potentially helpful in the differential diagnostic situation are AMACR and CK34βE12 (UrC versus CRC and PBAC), CK7, β-Catenin and CD15 (UrC and PBAC versus CRC), and CEA and GATA3 (UrC and CRC versus PBAC). Serum markers like CEA, CA19-9 and CA125 might additionally be useful in the follow-up and monitoring of UrC.

Lower tract neoplasm: Update of imaging evaluation

Cancers of the lower urinary tract can arise from the bladder, urachus or urethra. Urothelial carcinoma of the bladder (UCB) is the most common of these. The presentation of bladder, urachal and urethral cancers can differ but many result in hematuria as an initial indication. The diagnosis and staging of these cancers often necessitate radiologic imaging often in the form of cross-section CT urography or MR urography. The following article reviews the specific nature of lower tract cancers and their imaging.

A rare cause of urachal adenocarcinoma: urachal diverticle

Urachus is the remnant of the embryologic allantois and the fetal bladder, extending form the bladder roof to the umbilicus. It degenerates in the prenatal period into a tissue band known as the median umbilical ligament. Incomplete degeneration may lead to urachal diverticle development. It is difficult to diagnose unless it is considered in differential diagnosis and imaging modalities are employed. This paper describes a patient treated with partial cystectomy for urachal diverticle, and the pathologic examination revealed urachal adenocarcinoma.

Options for diagnosis and treatment of urachal carcinoma

Urachal carcinoma (UrC) is a rare but highly malignant epithelial cancer and commonly found in the urachal remnant which connects the dome of the bladder to the umbilicus via the ligamentum commune. Because of the specificity of the tumor location and its rarity, the diagnosis of UrC is often difficult. Although surgery is the treatment of choice for UrC, it still has a high incidence of local recurrence and distant metastasis and there are few modestly standard chemotherapy regimens for these patients (response rate 30-40%). Thus, the treatment of local recurrence and distant metastasis of UrC following surgery has been a challenge. We review the clinical diagnosis and therapy of UrC and factors related to its prognosis.