Urachal carcinoma is rare comprising less than 1% of all bladder
carcinomas.
Metastases of
urachal carcinoma have been reported to meninges, brain, ovary, lung, and maxilla. Cytologic features of metastatic
urachal carcinoma have not been previously reported. We present a case of metastatic
urachal adenocarcinoma in bronchial brushings and review the use of immunohistochemistry in its diagnosis. A 47-year-old female was seen initially in 2007 with
adenocarcinoma of the bladder dome for which she underwent
partial cystectomy. She presented in 2011 with a left lung mass and mediastinal
adenopathy. Bronchoscopy showed an endobronchial lesion from which brushings were obtained. These showed numerous groups of columnar cells with medium sized nuclei and abundant cytoplasm. The cells were positive for CK20 and CDX2 and negative for CK7. The cytomorphological findings were similar to those in the previous resection specimen and concurrent biopsy. This is the first case report of bronchial brushings containing metastatic
urachal carcinoma. No specific immunohistochemical profile is available for its diagnosis. The consideration of a second primary was a distinct possibility in this case due to the lapse of time from primary resection, absence of local disease, and lack of regional
metastases.