Sunday, May 8, 2011

Genitourinary cancer Urachal cancer part 3

Proper management of urachal carcinoma surgical requires that the diagnosis was made preoperatively on the basis of recognition of this possibility in the appropriate clinical setting. Before read this part, please read Genitourinary cancer Urachal cancer part 2 . Cross-sectional images are the key to recognize the diagnosis. On CT, urachal carcinoma usually appears as a mass of low attenuation in the dome of the bladder, usually in the midline or slightly to one side. Due to the relatively high rate of recurrence after treatment of this disease, the resection of the umbilicus, urachus, covering the peritoneum and posterior rectus fascia lateral to the medial umbilical ligament, bladder, and lymph nodes of the pelvis is now normal. The recognition that urachal tumors are predominantly extravesical and is not associated with a defect in the camp suggested to surgeons that in most cases, even bulky tumors could be completely resected with adequate margins and en bloc dissection only a partial cystectomy. Contemporary series report that neither local recurrence nor result threatened by this approach. On the contrary, survival is rather linked to the stage of presentation, presence of metastases in lymph nodes, and the ability to achieve a negative surgical margin with the completion of a partial or total cystectomy. Radical cystectomy is indicated for salvage surgery to treat a positive surgical margin, or delete a ligament from inadequate control of urachus - which occurs when the diagnosis was made before the operation. In a series of patients referred to MD Anderson Cancer Center is remarkable that only 19 of 35 patients undergoing primary surgical treatment was resection of the urachal ligament and umbilicus. The importance of adequate surgical treatment was reinforced by the finding that 13 of the 16 long-term survivors referred to in this series were treated with en bloc resection including umbilectomy.

Unfortunately, patients with lymph node or peritoneal discovered in surgery have a median survival of about 25 months, and demonstrate a clinical course that is virtually indistinguishable from that of patients with clinically evident metastases at diagnosis. In view of this finding, and demonstrated benefit of perioperative chemotherapy for colorectal cancer, the use of adjuvant or neoadjuvant chemotherapy for urachal cancer appears to be a reasonable consideration. Unfortunately, there are essentially not affect the data on this point directly, so we were left to extrapolate from our experience with other intestinal adenocarcinomas. Since we have some systemic therapies with clinically relevant response rates (see below), it seems appropriate to discuss adjuvant therapy in patients at high risk of recurrence, even those with tumors in the lymph nodes or peritoneal surface, or in the environment of inadequate surgery, including the presence of positive margins and in the scenario where the urachal ligament was not controlled.

As expected, few long-term survivors were observed after developing metastases. The sites most frequently involved are the bones, lungs, liver, lymph nodes and brain. Peritoneal carcinomatosis is common, especially in the context of positive surgical margins and when the peritoneal implants are present in the cystectomy.

Historically, chemotherapy has had little impact on the treatment of urachal cancer. This is particularly true in the context of traditionally used chemotherapy regimens for TCC. More recently, the responses have been reported in the establishment of schemes of 5-fluorouracil-based chemotherapy. Today, they are enrolling patients in a Phase II trial of combination chemotherapy with 5-fluorouracil, leucovorin, gemcitabine and cisplatin. The results in the first 20 patients showed an objective response in just over a third of patients. According to the clinical manifestations of this disease is so closely related to colorectal cancer, anecdotal responses have been observed in patients treated with capecitabine and irinotecan-based regimens, and the antibody cetuximab antiepidermal growth factor.