Liquid buccal mucosa graft endoscopic urethroplasty: a validation animal study.

PURPOSE: To validate a novel method of urethral stricture treatment using liquid buccal mucosal grafts (LBMG) to augment direct vision internal urethrotomy (DVIU) in an animal model. MATERIALS AND METHODS: A rabbit stricture model was used to test this method. Strictures were induced in 26 rabbits using electroresection of urethral epithelium. The animals were randomized into two groups: Group-1, treated with DVIU and LBMG in fibrin glue, and Group-2, DVIU with fibrin glue only. LBMG was prepared by suspension of mechanically minced buccal mucosa micrografts in fibrin glue. This LBMG-fibrin glue mixture was later injected into the urethrotomies of Group-1 animals. All animals were killed at 24 weeks after repeat retrograde urethrogram (RUG) and urethroscopy by surgeon blinded to the treatment arm. Radiographic images and histological specimens were reviewed by a radiologist and a pathologist, respectively, blinded to the treatment arm. Stricture treatment was considered a success if a diameter measured on RUG increased by ≥ 50% compared to pre-treatment RUG diameter. Histological specimens were assessed for the presence of BMG engraftment. RESULTS: In Group-1, 8/12(67%) animals demonstrated engraftment of LBMG, compared to none in Group-2 (p = 0.0005). 7/12(58%) in Group-1 showed radiographic resolution/improvement of strictures compared to 5/13 Group-2 rabbits (38%, p = 0.145). The median percent change for the Group-1 was 59%, compared to 41.6% for Group-2 (p = 0.29). CONCLUSION: This proof-of-concept study demonstrates feasibility of LBMG for endoscopic urethral stricture repairs. Further studies are needed to establish the role of this novel concept in treatment of urethral strictures.

Novel Concept and Method of Endoscopic Urethral Stricture Treatment Using Liquid Buccal Mucosal Graft.

PURPOSE: We describe a novel method of urethral stricture treatment using liquid buccal mucosal grafts to augment direct vision internal urethrotomy. MATERIALS AND METHODS: A rabbit stricture model was used to test this method. In phase 1 the concept of endoscopic liquid buccal mucosal graft implantation was tested by performing direct vision internal urethrotomy in 3 rabbits with immediate intraurethral injection of autologous liquid buccal mucosal grafts suspended in fibrin glue. Animals were sacrificed at 2 to 3 weeks and the urethras were examined for the presence of buccal mucosa engraftment. In phase 2 strictures were induced by electroresection in 9 rabbits divided into 2 groups, including 1) 6 rabbits treated with direct vision internal urethrotomy and liquid buccal mucosal grafts, and 2) 3 controls that underwent direct vision internal urethrotomy and injection of fibrin glue only. Two treated and 1 control animals were sacrificed at 8, 16 and 24 weeks each. Prior to sacrifice the animals underwent retrograde urethrograms and urethroscopy. Histological specimens were examined for the presence of buccal mucosal engraftment. RESULTS: In phase 1, 2 of the 3 rabbits demonstrated engraftment of buccal mucosa in the urethra after injection of liquid buccal mucosal grafts. In phase 2 all 6 treated animals demonstrated engraftment with resolution/improvement of strictures on retrograde urethrograms and urethroscopy. Controls had no buccal engraftment and showed fibrosis and chronic inflammation. One of the 3 controls had persistent stricture on retrograde urethrograms and cystoscopy. CONCLUSIONS: This proof of concept study demonstrated the feasibility of using liquid buccal mucosal grafts for endoscopic urethral stricture repair. Such a method may allow for wide application of this novel concept of using liquid buccal mucosal grafts to augment direct vision internal urethrotomy.

Robotic Assisted Caval Replacement for Recurrent Renal Cell Carcinoma Invading the Wall of the Inferior Vena Cava.

OBJECTIVE: To describe a case of robotic inferior vena cava (IVC) resection for an advanced case of renal cell carcinoma with accompanying robotic caval replacement using a synthetic graft. METHODS: In this report and accompanying video we describe a case of complete caval reconstruction with 3 year follow up. A 49-year-old male who at the age of 40 (9 years ago) had undergone right open partial nephrectomy for a pT1b 4.6 cm Fuhrman Grade 2 clear cell RCC with negative margins was found to have a recurrent mass at 6 years of follow up with suspicion of invasion into duodenum and IVC. For his recurrence, he underwent robotic assisted laparoscopic right radical nephrectomy and IVC resection followed by a placement of a 18 mm GORE-TEX graft anastomosed to the caudal and cephalad edges of the resected cava. RESULTS: The surgery was successfully completed using robotic assistance with a total operative time of 6 hours and 40 minutes and 900 cc blood loss. The patient experienced no intraoperative or perioperative complications and was discharged home on postoperative day #2. At 3 year of follow up there is no evidence of local recurrence. The radiology reports repeatedly commented on vascular structures "within normal limits." The patient had experienced no graft issues at a present follow up. CONCLUSION: This case provides a description of the surgery with video demonstration of technique as well as provides a few technical suggestions that may be useful for those who attempt similar surgery in the future.

Pannus Is the New Prepuce? Penile Cancer in a Buried Phallus.

Two males presented to our urology department with complaints of bleeding and malodor from buried phallus within a suprapubic fat pad. Although both men had neonatal circumcisions, advanced penile carcinoma was found in both men. Formal penectomies showed high grade, poorly differentiated squamous cell carcinoma invading the corporal bodies and urethra. Buried penis represents a difficulty in early detection of suspicious lesions but may also provide an environment susceptible to poor hygiene and subsequent chronic inflammation. Patients with buried penis may be at a higher risk for development of invasive penile cancer and may benefit from regular and thorough genital exams.