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Featured researches published by Petar Vukasin.


Archive | 1996

Wound recurrence following laparoscopic colon cancer resection

Petar Vukasin; Adrian E. Ortega; Frederick L. Greene; Glenn D. Steele; Anthony J. Simons; Gary J. Anthone; Lynn A. Weston; W Robert BeartJr.

INTRODUCTION: Multiple case reports have suggested that laparoscopic resection of colon cancer may alter the pattern or incidence of cancer recurrence. All reports lack a significant denominator to evaluate the incidence of surgical wound recurrence. We hypothesized that wound recurrence incidence is not increased by laparoscopic resection of colon cancer. METHODS: A prospective registry was initiated under the auspices of The American Society of Ccolon and Rectal Surgeons, American College of Surgeons, and Society of American Gastrointestinal Endoscopic Surgeons in 1992. Patients having laparoscopic colon resection were voluntarily entered and followed until June 1995. Recurrences were evaluated by the primary surgeon and reported to the registry. RESULTS: A total of 504 patients treated for cancer were identified in the registry. A minimum follow-up of one year was obtained for 480 of 493 evaluable patients (97.4 percent). Wound recurrence was identified in five patients (1.1 percent). Recurrence status was unknown in 18 patients (3.8 percent). CONCLUSION: Wound recurrence rates appear to be low. Although length of follow-up is limited, patterns of recurrence from previous studies suggest that 80 percent of recurrences should have occurred within one year. Given the limitations of a Phase II study, the hypothesis that recurrence rate is low is supported. However, prospective randomized trials are needed to establish if any difference in wound recurrence rates after laparoscopic or open resection of colorectal cancer exists.


Diseases of The Colon & Rectum | 1998

Follow-up of colorectal cancer

Michael Rosen; Linda Chan; W Robert BeartJr.; Petar Vukasin; Gary J. Anthone

PURPOSE: The value of intensive follow-up for patients after resection of colorectal cancer remains controversial. This study reviews all randomized and prospective cohort studies to assess the value of aggressive follow-up. METHODS: The literature was searched from the years 1972 to 1996 for studies reporting on the follow-up of patients with colorectal cancer. Randomized and comparative-cohort studies that included history, physical examination, and carcinoembrionic antigen values at least three times a year for at least two years were included in a meta-analysis. Single-cohort studies with intensive follow-up and traditional follow-up were also included in a two-group comparative analysis for each outcome indicator. Outcome indicators were 1) curative resection rates after recurrent cancer, 2) survival rates of curative re-resections, 3) length of survival after recurrence, and 4) cumulative five-year survival. RESULTS: Two randomized and three comparative-cohort studies met these criteria and included 2,005 patients, which were evaluated in the meta-analysis. The cumulative five-year survival was 1.16 times higher in the intensively followed group (P=0.003). Two and one-half times more curative re-resections were performed for recurrent cancer in those patients undergoing intensive follow-up (P=0.0001). Those patients in the intensive follow-up group with a recurrence had a 3.62-times higher survival rate than the control (P=0.0004). Fourteen single-cohort studies were also included in the comparative analysis of 6,641 patients. The findings from these aggregated studies support the results of the meta-analysis. CONCLUSION: Our study concludes that intensive follow-up detects more recurrent cancers at a stage amenable to curative resection, resulting in an improvement in survival of recurrences and an increased overall five-year cumulative rate of survival.


Annals of Surgical Oncology | 2002

Placement of self-expanding metal stents for acute malignant large-bowel obstruction: A collective review

Christine E. Dauphine; Patrick Y. Tan; W Robert BeartJr.; Petar Vukasin; Hartley Cohen; Marvin L. Corman

BackgroundThe purpose of this study was to review our experience with self-expanding metal stents as the initial interventional approach in the management of acute malignant large-bowel obstruction.MethodsTwenty-six patients who underwent placement of colonic stents at our institution between June 1994 and June 2000 were identified and reviewed.ResultsIn 14 patients, the stents were placed for palliation, whereas in 12, they were placed as a bridge to surgery. In 22 patients (85%), stent placement was successful on the first occasion. In the remaining four individuals, one was successfully stented at the second occasion, and three required emergency surgery. Nine of the 12 patients (75%) in the bridge-to-surgery group underwent elective colon resection. In the palliative group, four patients (29%) had reobstruction of the stents, and in one (9%), the stent migrated. In the remaining nine patients (64%), the stent was patent until the patient died or until the time of last follow-up (median, 156 days).ConclusionsIn our experience with 26 patients who developed a complete bowel obstruction as a consequence of a malignant tumor, placement of colonic stents to achieve immediate nonoperative decompression proved to be both safe and effective. Subsequent elective resection was accomplished in the majority of resectable cases.


Diseases of The Colon & Rectum | 1997

Variations in treatment of rectal cancer

Anthony J. Simons; Rhonda Ker; Susan Groshen; Conway Gee; Gary J. Anthone; Adrian E. Ortega; Petar Vukasin; Ronald K. Ross; W Robert BeartJr.

PURPOSE: Surgical options for the treatment of rectal cancer may involve sphincter-sparing procedures (SSP) or abdominoperineal resection (APR). We sought to examine variations in the surgical treatment of rectal cancer for a large, well-defined patient population and specifically to determine if differences exist in management and survival based on hospital type and surgical caseload. METHODS: The Cancer Surveillance Program database for Los Angeles County was used to retrospectively retrieve data on all patients who underwent SSP or APR for rectal adenocarcinoma between 1988 and 1992. RESULTS: A total of 2,006 patients with adenocarcinoma of the rectum underwent SSP or APR during the study period. Overall, 55 percent underwent SSP, and the remaining 45 percent underwent APR. Use of SSP remained relatively constant for each year of the five-year period. Substantial variability was seen in the use of SSP at various hospital types. For localized disease, this varied from as low as 52 percent at teaching hospitals to as high as 78 percent at hospitals approved by the American College of Surgeons (P=0.067). To examine the role of caseload experience, hospitals were divided into those completing an average of five or fewer rectal cancer cases per yearvs.those completing an average of more than five cases per year. For localized disease, hospitals with higher caseloads performed SSP in significantly more cases, 69vs.63 percent (P=0.049). Survival was seen to be significantly improved for patients operated on at hospitals with higher caseloads, in cases of both localized and regional diseases (P<0.001). CONCLUSION: Surgical choices in the treatment of rectal cancer may vary widely, even in a well-defined geographic region. Although the reasons for this variability are multifactorial, hospital environment and surgical caseload experience seem to have a significant role in the choice of surgical procedure and on survival.


Diseases of The Colon & Rectum | 1997

Oral fleet® phospho®-soda laxative-induced hyperphosphatemia and hypocalcemic tetany in an adult

Petar Vukasin; Lynn A. Weston; Robert W. Beart

PURPOSE: This study was undertaken to report an adverse outcome of the routine use of Fleet® Phospho®-Soda for bowel cleansing and to review the available literature. METHOD: Report of a case and review of the literature is presented. RESULT: Administration of Fleet® Phospho®Soda for bowel preparation in an adult resulted in hyperphosphatemia and hypocalcemic tetany. Review of the literature shows this to be the first such report. Further evaluation suggests a role for partial bowel obstruction and renal failure in this complication. CONCLUSION: Although Fleet® Phospho®-Soda solution continues to be a safe bowel preparation, caution should be used in adults with bowel obstruction and renal failure.


Diseases of The Colon & Rectum | 1998

New technique for mesh repair of paracolostomy hernias

Wayne L. Hofstetter; Petar Vukasin; Adrian E. Ortega; Gary J. Anthone; Robert W. Beart

Paracolostomy hernias are common and require treatment when symptomatic. Traditional methods of repair have high recurrence rates. We describe a new technique using polytetrafluorethylene mesh, which offers preservation of stoma site, lack of recurrences, ease, and safety.


Journal of Gastrointestinal Surgery | 2004

Effect of high-dose steroids on anastomotic complications after proctocolectomy with ileal pouch–anal anastomosis

Jeffrey P. Lake; Eiman Firoozmand; Jung-Cheng Kang; Panteleimon Vassiliu; Linda S. Chan; Petar Vukasin; Andreas M. Kaiser; Robert W. Beart

This review was designed to determine whether “high-dose” steroid therapy (≥20 mg prednisone/day) increases the likelihood of anastomotic complications after restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA). The hospital records of 100 patients undergoing proctocolectomy with IPAA were reviewed. Patient characteristics were analyzed to determine what factors were associated with higher rates of anastomosis-related complications. Seventy-one of our patients were given diverting ileostomies, whereas the remaining 29 underwent a single-stage procedure. Fifty-four percent of the patients in our review were taking steroids preoperatively, 39 of whom were on high-dose therapy. The overall anastomosis-related complication rate was 14%. There was no significant difference in complication rates with respect to age, steroid use, steroid dose, use of a diverting ileostomy, type of anastomosis, duration of disease, or presence of backwash ileitis. A trend toward higher leakage rates was found in patients undergoing single-stage procedures (10.3% vs. 2.8%, P = 0.14) as well as in patients undergoing single-stage procedures on high-dose steroids (22% vs. 5.0, P = 0.22). Nevertheless, neither of these trends was found to be statistically significant, which was likely infiuenced by the small sample size. Our data suggest that there may be an increase in anastomotic leakage rates in patients on high-dose steroids undergoing a single-stage proctocolectomy with IPAA. Nevertheless, our rate was not as high as the rates seen by other investigators and did not reach statistical significance. During preoperative counseling, patients on high-dose steroids should be informed of this uncertain but real risk of anastomotic leakage.


Diseases of The Colon & Rectum | 2004

Anorectal Pathology in HIV/AIDS-Infected Patients Has Not Been Impacted by Highly Active Antiretroviral Therapy

Claudia Gonzalez-Ruiz; Wesley Heartfield; Bill Briggs; Petar Vukasin; Robert W. Beart

PURPOSE:The aim of this study was to determine if the prevalence and distribution of anorectal pathology in HIV-infected patients treated by colorectal surgeons have changed after the introduction of highly active antiretroviral therapy.METHODS:The Los Angeles County–University of Southern California HIV Clinic is solely dedicated to the care of HIV patients. A colorectal clinic was established within this environment in 1991 and has served as the exclusive provider for the care of anorectal pathology in these patients. A prospective database of patients treated at this clinic was reviewed for two 18-month periods. The first group (early period) was composed of patients treated between January 1994 through June 1995, before the institution of more effective antiretroviral therapy. The second group (later period) consisted of patients treated between January 2001 through June 2002, after the introduction of highly active antiretroviral therapy. Data were tabulated for HIV-related anorectal pathologies, such as anal ulcer and anogenital condyloma, and non-HIV-related pathologies, including fissure, fistula in ano, hemorrhoids, perianal abscess, and other pathologies, for each of the two time periodsRESULTS:A total of 117 individual patients with anorectal pathology were treated in the early period and 109 received care in the later period, of which 107 were able to be evaluated. The pathology was distributed as follows for the early vs. late periods: 33 vs. 33 percent for ulcer, 30 vs. 34 percent for condyloma, 9 vs. 4 percent for fissure, 6 vs. 6 percent for fistula, 4 vs. 5 percent for hemorrhoids, 3 vs. 3 percent for abscess, and 15 vs. 16 percent for all other anorectal pathology. There was no statistically significant difference in any of these groups.CONCLUSION:The prevalence and distribution of both HIV-related and non-HIV-related anorectal pathology seen in our HIV patients have not been altered by the introduction of highly active antiretroviral therapy.


Diseases of The Colon & Rectum | 2003

Use of high-dose-rate brachytherapy in the management of locally recurrent rectal cancer.

Jonathan Kuehne; Thomas Kleisli; Peter Biernacki; Michael Girvigian; Oscar Streeter; Marvin L. Corman; Adrian E. Ortega; Petar Vukasin; Rahila Essani; Robert W. Beart

AbstractINTRODUCTION: Locally recurrent rectal cancer is associated with poor quality of life and has justified aggressive surgical and adjuvant approaches to control the disease. This study was designed to evaluate the use of fractionated perioperative high-dose-rate brachytherapy in association with wide surgical excision (debulking). Our hypothesis is that this combined therapy can help control locally recurrent rectal cancer. METHODS: Patients with biopsy-proven locally recurrent rectal cancer that could not be completely removed surgically were considered candidates for this procedure. All patients had abdominal exploration, aggressive tumor debulking, and placement of afterloading brachytherapy catheters. Patients underwent simulation on postoperative Day 3 and received 1,200 to 2,500 (mean, 1,888) cGy of fractionated high-dose-rate brachytherapy between postoperative Days 3 and 5. All patients had involvement of the lateral pelvic sidewall and/or the sacrum. RESULTS: Twenty-seven patients (18 males) aged 32 to 79 years underwent therapy. Follow-up ranged from 18 to 93 (mean, 50) months and was available in 27 patients. Ten patients (37 percent) were alive at the time of this report. Nine patients are without evidence of disease. Five patients (18 percent) died of non–cancer-related causes without evidence of recurrent disease. Five complications potentially related to treatment (3 abscesses, 2 fistulas) occurred in five patients. CONCLUSION: High-dose radiation brachytherapy delivers high-dose, highly controlled, focused radiation to specific sites of disease, thereby minimizing injury to normal tissues. The results in this series suggest increased local control, better palliation, and increased salvage of patients.


Diseases of The Colon & Rectum | 2009

Adenocarcinoma Arising in the Middle of Ileoanal Pouches : Report of Five Cases

Glenn T. Ault; Joseph W. Nunoo-Mensah; Laura Johnson; Petar Vukasin; Andreas M. Kaiser; Robert W. Beart

Restorative proctocolectomy with ileal pouch-anal anastomosis with or without mucosectomy has become the procedure of choice in patients with long-standing ulcerative colitis complicated by malignancy or medically refractory disease and for familial polyposis syndrome. Some reports have demonstrated the development of malignancy at the ileoanal anastomosis. We present a recent series of five patients who developed adenocarcinoma in the middle of their ileal pouch including the first case of pouch carcinoma in a patient who underwent pouch formation for ulcerative colitis. We discuss their presentation and management. Development of ileal pouch cancers, while rare, has been seen with increasing frequency in our practice. Patients with long-standing ileal pouches may benefit from routine surveillance of the pouch as often as every six months, which can be performed quickly and easily in the office using flexible endoscopy.

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Robert W. Beart

University of Southern California

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Andreas M. Kaiser

University of Southern California

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Adrian E. Ortega

University of Southern California

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Gary J. Anthone

University of Southern California

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Glenn T. Ault

University of Southern California

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Anthony J. Simons

University of Southern California

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Claudia Gonzalez-Ruiz

University of Southern California

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Lynn A. Weston

University of Southern California

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Marvin L. Corman

University of Southern California

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W Robert BeartJr.

University of Southern California

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