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Dive into the research topics where Marvin J. Lopez is active.

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Featured researches published by Marvin J. Lopez.


American Journal of Surgery | 1998

Electrocautery as a factor in seroma formation following mastectomy

KathaleenA Porter; Susan O’Connor; Eric B. Rimm; Marvin J. Lopez

BACKGROUND Electrocautery has been postulated as a factor in the risk of seroma formation after mastectomy. METHODS Eighty consecutive mastectomies in 74 patients were randomly assigned to dissection of the mastectomy flaps with either scalpel (n = 38) or electrocautery (n = 42). Total volume of fluid output through drains and aspirated from seromas was recorded. Other factors investigated included the type of drain utilized, estimated blood loss, and complications. RESULTS Seromas developed in 16 wounds in the electrocautery group compared with 5 in the scalpel group (38% and 13%, respectively; P = 0.01). Other factors with an independent risk for seroma included use of Jackson-Pratt drains compared with Blake drains (P = 0.006), and lower estimated blood loss (P = 0.006). No differences in characteristics of patients or in other complications were noted. CONCLUSIONS Use of electrocautery to create skin flaps in mastectomy reduced blood loss but increased the rate of seroma formation.


Clinical Infectious Diseases | 2007

The Impact of Cirrhosis on CD4+ T Cell Counts in HIV-Seronegative Patients

Barbara H. McGovern; Yoav Golan; Marvin J. Lopez; Daniel S. Pratt; Angela Lawton; Grayson Moore; Mark Epstein; Tamsin A. Knox

BACKGROUND Studies of the progression liver fibrosis in human immunodeficiency virus (HIV) and hepatitis C virus-coinfected patients suggest that cirrhosis is associated with immunosuppression, as measured by low absolute CD4(+) T cell counts. However, we hypothesized that, in patients with advanced liver disease, low CD4(+) T cell counts may occur secondary to portal hypertension and splenic sequestration, regardless of the presence or absence of HIV infection. METHODS Sixty HIV-seronegative outpatients with cirrhosis were enrolled during the period 2001-2003 in a prospective, cross-sectional study of the association between liver disease and CD4(+) T cell counts and percentages. Demographic characteristics, liver disease-related characteristics, and laboratory results--including CD4(+) T cell parameters--were collected. RESULTS A total of 39 patients (65%) had a low CD4(+) T cell count; 26 patients (43%) and 4 patients (7%) had CD4(+) T cell counts <350 and <200 cells/mm(3), respectively. Abnormal CD4(+) T cell counts were associated with splenomegaly (P=.03), thrombocytopenia (P=.002), and leukopenia (P<.001). The percentage of CD4(+) T cells was normal in 95% of patients who had a low absolute CD4(+) T cell count. CD4(+) T cell counts were significantly lower among cirrhotic patients than among 7638 HIV-seronegative historic control subjects without liver disease. CONCLUSIONS Cirrhosis is associated with low CD4(+) T cell counts in the absence of HIV infection. Discordance between low absolute CD4(+) T cell counts and normal CD4(+) T cell percentages may be attributable to portal hypertension and splenic sequestration. Our findings have significant implications for the use and interpretation of absolute CD4(+) T cell counts in HIV-infected patients with advanced liver disease.


Seminars in Surgical Oncology | 1999

Pelvic exenteration for advanced pelvic malignancy.

Philip J. Crowe; Walley J. Temple; Marvin J. Lopez; Alfred S. Ketcham

Pelvic exenteration is a demanding, yet potentially curative operation, for patients with advanced pelvic cancer. The majority will present with recurrence after prior surgery and radiotherapy. After exenteration, 5-year survival is 40% to 60% in patients with gynecologic cancer as compared to 25% to 40% for patients with colorectal cancer. Physiologic age and absence of co-morbidities appear to be more important when selecting patients for exenteration than chronological age. Careful pre-operative staging, including either computed tomography (CT) scan or magnetic resonance imaging (MRI), usually will identify patients with distant metastases, extrapelvic nodal disease, or disease involving the pelvic sidewall (which generally precludes surgery). The recent application of intra-operative radiotherapy or postoperative high-dose brachytherapy for patients with more advanced pelvic disease, which may include sidewall involvement, may expand the standard indications for exenteration. However, the intent of this procedure, with or without radiotherapy, should be resection of all tumor with the aim of cure since the place of palliative exenteration is controversial at best. The operative details of exenteration are presented, as are two surgical approaches to composite resection of pelvic structures in continuity with sacrectomy. Filling the pelvis with large tissue flaps, usually a rectus abdominus flap, has decreased morbidity rates, particularly with small bowel complications. Peri-operative mortality is usually 5% to 10%, and significant morbidity occurs in over 50% of patients. Restorative techniques for both urinary and gastrointestinal tracts can diminish the need for stomas and, along with vaginal reconstruction, can significantly improve quality of life for many patients after exenteration. These advances in surgery and radiotherapy help make the procedure a viable option for patients with otherwise incurable pelvic malignancy.


Surgical Clinics of North America | 1996

BREAST CANCER IN ELDERLY WOMEN: Presentation, Survival, and Treatment Options

Teresa Murray Law; Paul J. Hesketh; Kathaleen A. Porter; Lily Lawn-Tsao; Robert McAnaw; Marvin J. Lopez

Recent data suggest that breast cancer in elderly women does not present as more advanced disease, nor is survival significantly inferior to that in younger women. Unfortunately, until recently, older women have been excluded from clinical trials that have determined survival benefit in both screening and treatment modalities. Unless co-morbid conditions adversely affect ones life expectancy or tolerance to therapy, older women should be treated with standard surgical procedures (including breast conservation, if so desired) for early-stage disease, as outcome is comparable to that in younger patients. Adjuvant tamoxifen therapy has proven survival benefit in women over 70 years of age with estrogen receptor-positive tumors and should be considered in all women with tumors greater than 1 cm in size. Older women may experience more chemotherapy-related toxicities. However, for those with a significant risk of recurrence due to tumor size or lymph node status, chemotherapy can be safely administered when factors such as age-related decline in creatinine clearance and co-morbid conditions are considered. Hormonal therapy (tamoxifen) is usually the first-line treatment option over chemotherapy for metastatic disease in the elderly unless the patient has an estrogen receptor-negative tumor, visceral-dominant disease, or significant disease-related symptoms. In the latter settings, chemotherapy can provide improved or more rapid response proportions but does not affect long-term survival.


Annals of Surgical Oncology | 2003

Composite pelvic exenteration: Is it worthwhile?

Marvin J. Lopez; Pedro Luna-Pérez

BackgroundIn locally advanced pelvic cancer, tumor fixation to the bony pelvis is regarded as unresectable and often inoperable. Few data exist regarding the futility or utility of pelvic exenteration with en bloc resection of involved portions of the bony pelvis.MethodsThirty-four of 625 patients undergoing radical pelvic procedures had an en bloc resection of pelvic organs with portions of the bony pelvis. There were 19 female and 15 male patients, and the median age was 59 years. Primary neoplasms included 19 rectal, 6 cervicouterine, 4 anal, 3 vaginal, 1 sarcoma, and 1 penile. All but three patients underwent preoperative pelvic irradiation. Pelvic exenterations were posterior in 7 patients, anterior in 3, supralevator in 3, and total in 21 patients. Pelvic bony resections included portions of the sacrum-coccyx in 18 patients, ischium in 5, pubic symphysis in 4, and ischial pubic rami in 4, and hemipelvectomy was performed in 3.ResultsSurgical morbidity occurred in 67.6% (23) of 24 patients. Median follow-up was 37 months. Pelvic or perineal tumor recurrence was concurrent with distant metastases in 9 patients (26.4%); 6 (17.6%) had only distant relapse, and 2 (5.8%) died with local recurrence alone. Overall cancer-related mortality rate was 50%. Five-year overall and cancer-specific survival rates were 44% and 52%, respectively.ConclusionsSubstantial survival can be accomplished for patients whose tumors are fixed to limited portions of the bony pelvis. These procedures are still associated with substantial morbidity, but operative mortality is infrequent.


World Journal of Surgery | 2001

Preoperative Chemoradiation Therapy and Anal Sphincter Preservation with Locally Advanced Rectal Adenocarcinoma

Pedro Luna-Pérez; Saúl Rodríguez‐Ramírez; Darío Rodríguez-Coria; Armando Fernández; Sonia Labastida; Alejandro Silva; Marvin J. Lopez

Preoperative irradiation has been used to produce tumor regression and allow complete resection of rectal cancer with a sphincter-saving procedure. To evaluate the associated toxicity, the response in the primary tumor, and the postsurgical morbidity in a group of patients with locally advanced rectal cancer treated with preoperative chemoradiation therapy and low anterior resection, 120 patients were treated with 45 Gy of preoperative radiotherapy and a bolus infusion of 5-fluorouracil 450 mg/m2 on days 1 to 5 and 28 to 32 of radiotherapy. Four to six weeks later, 16 lesions were found unresectable; 36 patients underwent abdominoperineal resection or pelvic exenteration, and in the remaining 68 a low anterior resection was performed. For the purpose of this study only the latter group was included. There were 38 men and 30 women, with a mean age of 54.7 ± 13.1 years. Gastrointestinal and hematologic acute toxicity grade 3 to 4 occurred in 12 and 7 patients, respectively. The mean distance of the tumor above the anal verge was 8.2 ± 2.6 cm. In 10 patients the surgical resection included neighboring pelvic organs; 16 patients (23.5%) required a temporary diverting colostomy. The main causes of surgical morbidity were clinical anastomotic leakage in seven (10%), abdominal wall infection in five (7.4%), anastomotic stenosis in three (4.5%), and intraabdominal abscess in one (1.5%). No operative deaths occurred. The postsurgical stages were as follows: no tumor in the specimen, 17 (25%); T1, 4 (6%); T2, 12 (17%); T3, 17 (25%); T4, 5 (7%); any T with N+, 9 (13%); and any T, N with M+, 4 (6%). The median and mean follow-ups were 30.0 months and 37.4 ± 25.0 months, respectively. The local recurrence rate was 2.9%, and the distant recurrence rate was 17%. The administration of preoperative chemoradiation therapy for locally advanced rectal cancer is associated with tolerable toxicity, a high rate of response in the primary tumor that allowed anal sphincter preservation, and a low rate of local recurrence.


Surgical Clinics of North America | 1996

THE CURRENT ROLE OF PROPHYLACTIC MASTECTOMY

Marvin J. Lopez; Kathaleen A. Porter

Prophylactic mastectomy has a role in preventing breast cancer in the woman at high risk. The rare indications for this operation are based on genetic and histologic factors that affect relative or cumulative risk. Evaluation of women at high risk must draw on multidisciplinary expertise, including genetic counseling. If prophylactic mastectomy is recommended, skin-sparing total mastectomy (not subcutaneous) with autogenous tissue reconstruction is the preferred approach.


Journal of Surgical Oncology | 1999

Exenterative pelvic surgery

Marvin J. Lopez; John S. Spratt

A review of the history, indications, basic technique, end results, and complications of exenterative surgery for pelvic neoplasms is provided. The authors discuss their broad personal experience with the operation. Much of this experience evolved from work at Barnes Hospital and the Ellis Fischel State Cancer Hospital. The techniques are applicable to advanced neoplasms of the cervix uteri, scrotum, urinary bladder, and other, less frequent neoplasms still confined to the pelvis. J. Surg. Oncol. 1999;72:102–104.


American Journal of Surgery | 1990

Multimodal therapy in locally advanced breast carcinoma

Marvin J. Lopez; Dorothy P. Andriole; William G. Kraybill; Ali Khojasteh

Among 879 patients treated for breast cancer between 1975 and 1984, advanced disease was found in 125 (14%). A subgroup of 34 (4%) presented with untreated locally advanced disease without demonstrable distant metastases at the time of diagnosis (stage IIIB = T4abed, NX-2,MO). During the first 5 years (1975 through 1979), 17 patients were treated primarily with sequential radiotherapy and chemotherapy (Group A). From 1980 to 1984 (Group B), the management consisted of four courses of induction multi-drug chemotherapy followed primarily by mastectomy and additional chemotherapy. The mean follow-up for the most recent group (Group B) is 48 months. Follow-up was complete. While the local disease control rate was the same for both groups (76%), the survival was remarkably different. Group A patients experienced a median survival of 15 months, and only one survived 5 years. In Group B, the median survival was 56 months with nine patients (53%) alive between 40 and 76 months, seven (41%) of whom are 5-year survivors. While the overall mortality of patients with inflammatory breast cancer was greater in both groups when compared with the group with noninflammatory disease, the survival of patients in Group B was better than in Group A for both inflammatory and noninflammatory cancers (p less than 0.01). Estrogen receptor, nodal, and menopausal status did not influence survival. These data suggest that neoadjuvant chemotherapy improves survival for patients with stage IIIB breast carcinoma and delays the establishment or progression of distant metastases. Mastectomy is an important component in the treatment of this disease.


JAMA Surgery | 2013

Laparoscopic vs Open Ventral Hernia Repair in the Era of Obesity

Justin Lee; Allan Mabardy; Reza Kermani; Marvin J. Lopez; Nicole Pecquex; Anthony McCluney

IMPORTANCE This study analyzes a role of laparoscopy in obese patients with ventral hernia. OBJECTIVE To evaluate the outcomes of laparoscopic compared with open ventral hernia repair (VHR) in obese patients. DESIGN Retrospective cohort analysis. SETTING Nationwide hospital survey. PARTICIPANTS Obese patients undergoing VHR from 2008 through 2009 were selected from the Nationwide Inpatient Sample database. MAIN OUTCOMES AND MEASURES Data analysis included intraoperative and postoperative complications, length of stay, and total hospital charges. Additional patient demographics, including insurance, median income, and locations, were analyzed. RESULTS Of the 47,661 obese patients who underwent VHR during the study period, laparoscopic VHR increased more than 4-fold, from 1547 of 23,917 (6.5%) to 6629 of 23,704 (28.0%) (P < .001). Laparoscopic VHR was associated with a lower overall complication rate (6.3% vs 13.7%; P < .001), shorter median length of stay (3 vs 4 days; P < .001), and lower mean total hospital charges (

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David R. Cave

University of Massachusetts Medical School

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Pedro Luna-Pérez

Mexican Social Security Institute

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Andrew B. Leiter

University of Massachusetts Medical School

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John S. Spratt

University of Louisville

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