Pathology

Abstract

The use of fibrin sealants in urology has been particularly popular recently, due to its use in laparoscopic kidney surgery. With the expanding role of laparoscopy for partial nephrectomy, methods to better control urinary leak or bleeding have been explored. Aside from direct suturing of the collecting system and vessels, fibrin sealants have been the "suspenders" to the "belts" of suturing. The current commercially available sealants are Tisseel "fibrin sealant", (by Baxter, a mix of fibrinogen aprotonin solution, Factor XIII, and human derived thrombin), FloSeal "gelatin matrix" (by Baxter, a mix of human derived thrombin and bovine derived gelatin matrix), and BioGlue "surgical adhesive" (by Cryolife, a mix of bovine serum albumin and gluteraldehyde). Results: HE showed clear cells, arranged in a pseudopapillary architecture, with retention of morphology in the metastatic tumor deposits. By IHC there was strong nuclear positivity for TFE3 in all cases and focal stain for AE3 and vimentin; stains for HMB45, calretinin, pankeratin and AE1 were all negative. By EM (2/5 cases examined) there were junctional complexes and rudimentary microvilli. In one case there were abundant lipid droplets and glycogen; in a second case, rare rhomboid crystals, similar to those seen in alveolar soft part sarcoma, were present. All patients (3 Caucasian, 2 Hispanic) presented with innocuous complaints, abdominal/flank pain and hematuria, and lacked any significant prior history. All but one patient presented with distant metastases at the time of diagnosis, and all patients were diagnosed with additional metastases or tumor recurrence within 5 months of presentation. Treatments included tumor resection, interleukin-2 therapy, combination chemotherapy, and radiation therapy, all with minimal success. Patients followed a rapidly terminal course, with a mean survival of 15 months post-diagnosis (range 10-20 months). One patient is currently undergoing chemotherapy at 13 months post-diagnosis (with brain metastasis), and another patient is alive at 6 months post-diagnosis, with metastases. Conclusions: The patients presented here were older than typically described for TFE3-RCC. Although tumor morphology was similar to pediatric patients, these adult patients had a very aggressive clinical course compared to pediatric TFE3-RCC and even to conventional, adult-type RCC. Consistent use of antibodies against TFE3 in all tumors, regardless of patient age, may expand the spectrum of Xp11.2 translocation RCC with respect to age, clinical behavior and molecular abnormalities. Dr Urological Survey Editorial CommentThese carcinomas are defined by several different translocations involving chromosome Xp11.2. The t(X; 1) (p11.2; q21) translocation results in the fusion of TFE3 gene in chromosome X to PRCC gene in chromosome 1; the t(X; 17) (p11.2; q25) translocation results in the fusion of TFE3 gene in chromosome X with the ASPL gene in chromosome 17. This latter translocation is also seen in the alveolar soft part sarcoma. These carcinomas pr...