PubMed Health⌕ Search

Biomedical subjects

Michael D Stifelman

Publications and source records attributed to Michael D Stifelman.

10 recordsLinked to original sources

Impact of discordant radiologic and pathologic tumor size on renal cancer staging.

OBJECTIVES: To determine whether the discrepancy in the radiologic and pathologic size of renal cell carcinoma influences the final cancer stage. METHODS: Renal masses resected from December 1999 to September 2004 were identified using a pathologic database and compared by surgical accession number to an existing clinical renal tumor database to identify those T1 and T2 tumors for which radiologic and pathologic data were available. The tumor histologic features, maximal pathologic diameter, and maximal radiologic diameter were recorded. The percentage of tumor size reduction was then calculated using these data. RESULTS: Of the 236 renal cancers evaluated, 52% had regressed in size when comparing the pathologic and radiologic sizes. When stratified by histologic subtype, clear cell tumors regressed more often and to a greater degree than those that were chromophobe or papillary. Also, 15 organ-confined tumors were downstaged when comparing the maximal radiologic diameter and the maximal pathologic diameter, and 13 of these were clear cell tumors. CONCLUSIONS: A reduction in kidney tumor size is commonly observed at surgical resection because of a loss of blood flow to the tumor. This tumor size reduction has an impact on the final pathologic stage in organ-confined tumors for which size is the only criterion. The greatest tumor size reduction, and most frequent downstaging, was observed for conventional (clear cell) tumors. We believe this may explain, in part, the worse stage-stratified outcomes for clear cell tumors compared with other tumor types. We propose that renal cancer staging should be determined from accurate measurement of the radiologic size, rather than the pathologic size.

Adult↗

Robot assisted laparoscopic partial nephrectomy: initial experience.

PURPOSE: Advances in laparoscopy have made laparoscopic partial nephrectomy a technically feasible procedure but it remains challenging to even experienced laparoscopists. We hypothesized that robotic assisted laparoscopic partial nephrectomy may make this procedure more efficacious than the standard laparoscopic approach. MATERIALS AND METHODS: Ten patients with a mean age of 58 years and mean tumor size of 2.0 cm underwent robotic assisted laparoscopic partial nephrectomy and another 10 with a mean age of 61 years and mean tumor size of 2.18 cm underwent laparoscopic partial nephrectomy, as performed by a team of 2 surgeons (MS and ST) between May 2002 and January 2004. Demographic data, intraoperative parameters and postoperative data were compared between the 2 groups. RESULTS: There were no significant differences in patient demographics between the 2 groups. Intraoperative data and postoperative outcomes were statistically similar. In the 10 patients who underwent robotic assisted laparoscopic partial nephrectomy there were 2 intraoperative complications. There was 1 conversion in the laparoscopic partial nephrectomy group. CONCLUSIONS: Robotic assisted laparoscopic partial nephrectomy is a safe and feasible procedure in patients with small exophytic masses. The robotic approach to laparoscopic partial nephrectomy does not offer any clinical advantage over conventional laparoscopic nephrectomy.

Humans↗

Robotic ureterolysis, retroperitoneal biopsy, and omental wrap for the treatment of ureteral obstruction due to idiopathic retroperitoneal fibrosis.

Retroperitoneal fibrosis (RPF) is a rare disorder of unclear etiology characterized by chronic inflammation of the retroperitoneum, which can involve any of the retroperitoneal structures, most notably the ureters, aorta, and vena cava. Historically, open biopsy, ureterolysis, and transpositioning or omental wrapping of the involved ureter(s) have been the preferred surgical treatments of RPF, with success rates greater than 90%. More recently, successful laparoscopic biopsy, ureterolysis, and ureteral omental wrapping and intraperi-tonealization have been described. We report the first case in the literature of idiopathic RPF managed with robotic ureterolysis and laparoscopic omental ureteral wrapping.

Case Reports↗

Work-up of the functional adrenal mass.

Evaluation of a functional adrenal mass may be initiated based on symptomatic presentation or the detection of an incidental adrenal mass. Recent literature suggests that 10% to 20% of adrenal incidentalomas demonstrate subclinical hormonal dysfunction, which may place patients at a higher risk for metabolic or cardiovascular disorders. Many diagnostic algorithms have been proposed for the evaluation of pheochromocytoma, Cushing's adenoma, aldosteronoma, and hormonally active adrenal cortical carcinoma. In this article, the available literature on functional adrenal masses is reviewed and up-to-date methods of efficient diagnosis are proposed.

Adenoma↗

Robot-assisted laparoscopic dismembered pyeloplasty: a combined experience.

BACKGROUND AND PURPOSE: The need for advanced laparoscopic skills limits the implementation of laparoscopic pyeloplasty to centers with extensive experience. The introduction of robotic technology into the field of minimally invasive surgery has facilitated complex surgical dissection and genitourinary reconstruction. We report our experience with robot-assisted laparoscopic pyeloplasty using the daVinci Surgical System at three New York City medical centers. PATIENTS AND METHODS: A retrospective review of all robot-assisted laparoscopic Anderson-Hynes dismembered pyeloplasty cases in 18 female and 17 male patients between April 2001 and January 2004 was performed. The average patient age was 39.0 years (range 15-69 years). All patients had symptoms or radiographic evidence of ureteropelvic junction (UPJ) obstruction. Robotic assistance with the daVinci Surgical System was employed after preparation of the UPJ with a standard laparoscopic approach. RESULTS: The mean operative time and suturing time was 216.4 +/- 52.9 minutes and 63.0 +/- 14.2 minutes, respectively. The average estimated blood loss was minimal at 73.9 +/- 58.3 mL. The mean length of hospitalization was 69.4 hours (range 28-310 hours). The average use of intravenous morphine was 28.4 mg (range 0-162 mg). There were no intraoperative complications or open conversions. A mean follow-up of 7.9 months revealed a success rate of 94%, with two patients requiring further treatment. CONCLUSIONS: This combined multi-institutional series reveals that robot-assisted pyeloplasty with the daVinci Surgical System is safe and reproducible. These intermediate results appear comparable to those of open and laparoscopic pyeloplasty repairs.

Adolescent↗

Robot-assisted laparoscopic partial nephrectomy: the NYU technique.

The introduction of the daVinci surgical system has changed the way both surgeon and patient view radical prostatectomy. We hypothesized that the same theoretical and tangible benefits may be realized when employing the system for partial nephrectomy. This paper reviews our technique of robot-assisted laparoscopic partial nephrectomy (RALPN) utilizing the daVinci surgical system. Intraoperative hilar clamping is utilized in all cases. With the daVinci system, the tumor is excised with cold scissors, biopsies are taken from the base for frozen-section study, sutures are placed at the base, Gelfoam/fibrin glue is activated in the defect, a Surgicel bolster is laid in the defect, and mattress sutures are placed prior to releasing the clamp. After performing 12 RALPNs, it appears this technique is safe, feasible, and reproducible both for small exophytic masses and for deeper lesions involving the collecting system. A RALPN requires two surgeons, both well versed in laparoscopic and robotic techniques.

Biopsy↗

Hand-assisted laparoscopic devices: the second generation.

BACKGROUND AND PURPOSE: Hand-assisted laparoscopic (HAL) nephrectomy is an increasingly popular surgical modality. Within the last year, three newly designed second-generation hand-assist devices have emerged with the intention to improve efficacy and ease of use. We prospectively evaluated and compared these with each other and with the first-generation devices. MATERIALS AND METHODS: A total of 130 urologists performed two HAL nephrectomies in a porcine laboratory using two different hand devices at an American Urological Association-sponsored learning course. Sixty-three urologists utilized the second-generation devices (Gelport, Omniport, LapDisc), while 67 urologists used the first-generation devices (Handport, Intromit, PneumoSleeve). Each surgeon completed a 12-question survey evaluating the devices. RESULTS: Evaluation of the second-generation devices revealed that Gelport was statistically significantly superior in all parameters to the Omniport and in 5 of 10 parameters to the LapDisc. Comparison of the first- and second-generation devices revealed that only the Gelport achieved a significant increase in all ratings. Among the first-generation devices, no device scored better than 8.27 of 10 in any category. Analysis of the second-generation devices demonstrated that the Gelport scored a rating above 8.25 in all parameters with an overall satisfaction score of 8.59. Both the Omniport and the LapDisc attained ratings comparable to those of the first-generation devices. CONCLUSION: The HAL procedure relies heavily on devices that allow the hand to be introduced into the laparoscopic environment. The Gelport, when evaluated in a porcine model by training laparoscopic urologists, appears to be significantly better than other devices available to date. Further testing with larger cohorts and human clinical trials are required to confirm these findings.

Animals↗

Hand-assisted laparoscopy for large renal specimens: a multi-institutional study.

OBJECTIVES: To present our experience with hand-assisted laparoscopy (HAL) for larger renal specimens. One of the theoretical benefits of HAL is the ability to manage large renal specimens, which we defined as tumors greater than 7 cm, and tumors in obese patients. METHODS: Between March 1998 and October 2000, 106 HAL radical nephrectomies were performed for enhancing renal masses, for which 95 patients had complete preoperative, intraoperative, and postoperative data. Of the 95 patients, 32 underwent HAL for large tumors (7 cm or greater) and 41 had a body mass index of 31 or greater. The demographic and outcome data of these two groups were compared with 63 patients who underwent HAL for tumors less than 7 cm and 54 patients with a body mass index of less than 31. RESULTS: When comparing cohorts by tumor size, the only statistically significant differences were in convalescence and specimen weight. Patients with lesions 7 cm or greater required 21 days to recover compared with 18 days for patients with lesions less than 7 cm. Obese patients had statistically significantly higher American Society of Anesthesiologists classifications, longer operative times (214 versus 176 minutes), and longer convalescences (21 versus 17.5 days) compared with nonobese patients. The estimated blood loss and conversion rate was not different between the groups. Furthermore, no difference was noted between the groups in the incidence of positive margins, local recurrence, or metastatic recurrence at a mean follow-up of 12.2 months. CONCLUSIONS: HAL provides a safe, reproducible, and minimally invasive technique to remove large renal tumors and renal tumors in the obese.

Blood Loss, Surgical↗

Laparoscopic radical nephrectomy: oncologic efficacy.

Laparoscopic radical nephrectomy has evolved tremendously over the past decade to the point where it should be considered the standard of care for localized renal tumors not amenable to nephron-sparing surgery. The benefits of decreased postoperative pain, shortened hospital stay, quicker convalescence, and improved cosmesis have been proved in numerous studies. Long-term oncologic results of LRN have demonstrated equivalent outcomes to ORN.

Humans↗

Robot-assisted laparoscopic partial nephrectomy.

The indications for nephron-sparing surgery and for minimally invasive surgery are continually expanding. Nephron-sparing surgery, also known as partial nephrectomy, presents a challenge to the minimally invasive surgeon. Herein, we describe our technique of robot-assisted laparoscopic partial nephrectomy. This approach may have potential advantages of including easier excision and suturing. Moderate training is required.

Aged↗