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Dive into the research topics where Guillermo Ojea Quintana is active.

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Featured researches published by Guillermo Ojea Quintana.


Journal of The American College of Surgeons | 2002

Simultaneous colorectal and hepatic resections for colorectal cancer: postoperative and longterm outcomes

Eduardo De Santibanes; Fernando A Bonadeo Lassalle; Lucas McCormack; Juan Pekolj; Guillermo Ojea Quintana; Carlos Vaccaro; Mario Benati

BACKGROUND Our goal was to analyze the results of resection of colorectal cancer and liver metastases in one procedure. STUDY DESIGN Between June 1982 and July 1998, 522 patients underwent liver resection for colorectal metastases. Liver resection was performed simultaneously with colorectal resection in 71 cases, representing the population in this study. Morbidity, mortality, overall survival, and disease-free survival times were analyzed. Median followup time was 29 months (range 6 to 162 months). Prognostic factors and their influence on outcomes were analyzed. RESULTS The median hospital stay was 8 days (range 5 to 23 days). Morbidity was 21% and included nine pleural effusions, seven wound abscesses, four instances of hepatic failure, three systemic infections, three intraabdominal abscesses, and one colonic anastomosis leakage. Operative mortality was 0%. Recurrence rate was 57.7% (41 or 71), and progression of disease was detected in 33.8%. Overall and disease-free survivals at 1, 3, and 5 years were 88%, 45%, and 38% and 67%, 17%, and 9%, respectively. Prognostic factors with notable influence on patient outcomes were nodal stage as per TNM classification, number of liver metastases, diameter (smaller or larger than 5 cm), liver resection specimen weight (lighter or heavier than 90 g), and liver resection margin (smaller or larger than 1 cm). CONCLUSIONS Simultaneous resection of colorectal cancer and liver metastases can be performed with low morbidity and mortality rates, avoiding a second surgical procedure.


Diseases of The Colon & Rectum | 2009

Lymph Node Ratio as Prognosis Factor for Colon Cancer Treated by Colorectal Surgeons

Carlos Vaccaro; Victor Im; Gustavo Rossi; Guillermo Ojea Quintana; Mario Benati; Diego Perez de Arenaza; Fernando Bonadeo

PURPOSE: This study was designed to assess the prognostic value of the lymph node ratio in patients with colon cancer treated by colorectal specialists. METHODS: Three hundred and sixty-two Stage III consecutive cases were analyzed based on quartiles: lymph node ratio 1 (>0 and <0.06); lymph node ratio 2 (between 0.06 and 0.12); lymph node ratio 3 (>0.12 and <0.25); lymph node ratio 4 (≥0.25). RESULTS: Disease-free survival rates were: lymph node ratio 1, 75.5%; lymph node ratio 2, 74.2%; lymph node ratio 3, 73.2%; and lymph node ratio 4, 40.1%. Similar differences were observed for cancer-specific and overall survival rates. Cases with lymph node ratio ≥0.25 had higher hazard ratios than cases with lymph node ratio <0.25 in terms of disease-free survival (2.8, P < 0.001), cancer-specific survival (3.1, P = 0.0001), and overall survival (2.2, P = 0.0001). The hazard ratio of cases with up to three positive nodes and lymph node ratios ≥0.25 was higher than that of cases with up to three positive nodes and lymph node ratios <0.25 in terms of disease-free survival (3.1, P = 0.003), cancer-specific survival (3.5, P = 0.002), and overall survival (2.4, P = 0.02). Similar differences were found for cases with more than three positive nodes. Lymph node ratio, but not number of positive nodes, had independent prognostic value in multivariate analysis. No interaction between these two variables was found. CONCLUSION: A lymph node ratio ≥0.25 was an independent prognostic factor in Stage III colon adenocarcinoma regardless of the number positive nodes. It modified outcomes predicted by the current staging system.


Diseases of The Colon & Rectum | 2004

Colorectal Cancer Staging: Reappraisal of N/PN Classification

Carlos Vaccaro; Fernando Bonadeo; Mario Benati; Guillermo Ojea Quintana; Fernando Rubinstein; Eduardo Mullen; Margarita Telenta; José Lastiri

PURPOSE: Current American Joint Committee on Cancer and the Union Internationale Contre le Cancer TNM classification disregards location of positive nodes, discontinuing N3 category, which constitutes a major modification to 1987 version. This study was designed to assess the impact of the recategorization of former N3 cases and the reliability of the current N1-N2 subcategorization of Stage III patients. METHODS: Prospectively collected data from 1,391 patients (55.8 percent males; median age, 64 (range, 21–97) years), operated on with curative intent between 1980 and 1999, were analyzed. The median follow-up was 60 (interquartile range, 27–97) months with 129 cases lost to follow-up. RESULTS: Of positive node cases, 25.3 percent were former N3. Among them, 30.5 percent migrated to the N1 group and 69.5 percent to the N2 group. The proportions of former N3 cases in N1 and N2 groups were 12.5 percent and 46.1 percent, respectively (P < 0.001). Node-positive patients had an actuarial five-year survival rate of 56.7 percent (95 percent confidence interval, 53–59), with a significant difference between N1/N2 categories (63.6 vs. 44.1 percent, respectively; P < 0.001). Although apical node involvement and more than three positive nodes were associated with poorer outcomes in univariate analysis, only the number of positive nodes had independent association (hazard ratio, 1.6 (range, 1.2–2.2); P < 0.001). Integration of former N3 cases did not modify outcomes. CONCLUSIONS: The recategorization of former N3 involved a high proportion of positive node cases. Current N1/N2 categories clearly defined different outcomes and were not modified by the integration of former N3.


Diseases of The Colon & Rectum | 2014

Laparoscopic colorectal resections: a simple predictor model and a stratification risk for conversion to open surgery.

Carlos Vaccaro; Gustavo Rossi; Guillermo Ojea Quintana; Enrique R. Soriano; Hernán Vaccarezza; Fernando Rubinstein

BACKGROUND: The advantages associated with the laparoscopic approach are lost when conversion is required. Available predictive models have failed to show external validation. Body surface area is a recently described risk factor not included in these models. OBJECTIVE: The aim of this study was to develop a clinical rule including body surface area for predicting conversion in patients undergoing elective laparoscopic colorectal surgery. DESIGN: This was a prospective cohort study. SETTING: This study was conducted at a single large tertiary care institution. PATIENTS: Nine hundred sixteen patients (mean age, 63.9; range, 14–91 years; 53.2% female) who underwent surgery between January 2004 and August 2011 were identified from a prospective database. MAIN OUTCOME MEASURES: Conversion rate was analyzed related to age, sex, obesity, disease location (colon vs rectum), type of disease (neoplastic vs nonneoplastic), history of previous surgery, and body surface area. A predictive model for conversion was developed with the use of logistic regression to identify independently associated variables, and a simple clinical prediction rule was derived. Internal validation of the model was performed by using bootstrapping. RESULTS: The conversion rate was 9.9% (91/916). Rectal disease, large patient size, and male sex were independently associated with higher odds of conversion (OR, 2.28 95%CI, 1.47–3.46]), 1.88 [1.1–3.44], and 1.87 [1.04–3.24]). The prediction rule identified 3 risk groups: low risk (women and nonlarge males), average risk (large males with colon disease), and high risk (large males with rectal disease). Conversion rates among these groups were 5.7%, 11.3%, and 27.8% (p < 0.001). Compared with the low-risk group, ORs for average- and high-risk groups were 2.17 (1.30–3.62, p = 0.004) and 6.38 (3.57–11.4, p < 0.0001). LIMITATIONS: The study was limited by the lack of external validation. CONCLUSION: This predictive model, including body surface area, stratifies patients with different conversion risks and may help to inform patients, to select cases in the early learning curve, and to evaluate the standard of care. However, this prediction rule needs to be externally validated in other samples (see Video, Supplemental Digital Content 1, http://links.lww.com/DCR/A137).


Diseases of The Colon & Rectum | 2012

Body surface area: a new predictor factor for conversion and prolonged operative time in laparoscopic colorectal surgery.

Carlos Vaccaro; Hernán Vaccarezza; Gustavo Rossi; Ricardo Mentz; Victor Im; Guillermo Ojea Quintana; Nadia Peralta; Enrique R. Soriano

BACKGROUND: Body surface area is a measurement of body size used in clinical settings. Its impact on laparoscopic colorectal surgery has not been previously studied. OBJECTIVE: The aim of this study was to assess the impact of body surface area on the conversion rate and laparoscopic operative time. DESIGN: This study was conducted as a retrospective analysis of prospectively collected data SETTING: This study was conducted at a single tertiary care institution. PATIENTS: Nine hundred sixteen consecutive patients operated on between January 2004 and August 2011 were identified from a prospective database. MAIN OUTCOME MEASURES: Conversion rate and laparoscopic operative time were analyzed related to age, sex, obesity, disease location (colon vs rectum), type of disease (neoplastic vs nonneoplastic), history of previous surgery, and body surface area; body surface area was calculated by the Mosteller formula. Body surface area was analyzed by the use of median and quartile cutoff values (1.6, 1.8, and 2.0). Multivariate models were adjusted for different confounders. Interaction between body surface area and BMI was ruled out. RESULTS: The conversion rate was 10%. Conversion rates for quartiles 1, 2, 3, and 4 were 4.4%, 8.3%, 12.7%, and 14.8%, p = 0.001. Patients with body surface area≥1.8 had a higher conversion rate than those with body surface area <1.8 (13.9% vs 5.3%, OR: 2.35 (95% CI: 1.45–3.86; p = 0.0001)). Multivariate analysis showed that body surface area ≥1.8 was associated with conversion (OR: 2, 95% CI: 1.1–3.7, p = 0.02) and a longer operative time after adjusting for sex, age, obesity, disease location (rectum vs colon), and type of laparoscopic approach. LIMITATION: This was a single-institution retrospective study. CONCLUSION: Body surface area is a predictor for conversion and longer laparoscopic operative time. It should be considered when informing patients, selecting cases in the early learning curve, and assessing standard of care.


Molecular Medicine Reports | 2008

Association between mast cells of different phenotypes and angiogenesis in colorectal cancer

Laura V. Mauro; Mariana Bellido; Ana Morandi; Fernando Bonadeo; Carlos Vaccaro; Guillermo Ojea Quintana; María Guadalupe Pallotta; José Lastiri; Lydia Puricelli; Lilia Lauria de Cidre

It is known that mast cells proliferate in solid tumours and increase tumour angiogenesis. Nevertheless, there is no consensus regarding their role in colorectal cancer (CRC). In this study, we aimed to clarify the relationship of mast cells positive for tryptase (MCts) and tryptase-chymase (MCtcs) with microvessel density (MVD) in the intratumoral zone and the invasive edge of 80 CRC patient tumours. We evaluated these parameters and associated their expression with clinicopathological parameters, including survival rate. Tumour sections from each patient were immunostained for tryptase to evaluate MCts, chymase to evaluate MCtcs, and CD34 to evaluate microvessel counts under x100 microscopy. The number of MCs of both phenotypes and the MVD counts were higher in the invasive edge than in the intratumoral zone (p<0.001). MCt numbers were higher than those of MCtcs in all Astler-Coller stages in both regions. A positive correlation between MVD and MCts or MCtcs was observed (Pearsons test p<0.001). Neither the number of MCs nor MVD was associated with overall survival (log rank test). However, only 8.3% of patients with low numbers of MCtcs in the invasive edge succumbed to the disease, compared to 32% with high numbers of MCtcs. Our results indicate that angiogenesis and MC hyperplasia are events which appear early during CRC development. The correlation of MC phenotypes with MVD is in agreement with the role attributed to MCs, that of angiogenesis enhancement. Collectively, these findings suggest that screening during the early malignization of CRC can provide valuable clinical information.


CRSLS: MIS Case Reports from SLS | 2014

Laparoscopic Colectomy for Colon Cancer After Liver Transplantation

Gustavo Rossi; Ricardo Mentz; Carlos Vaccaro; Fernando A. Alvarez; Guillermo Ojea Quintana

Introduction: Colon cancer in liver transplant patients is an uncommon clinical situation. These patients are considered of high risk and are classically treated with an open approach. Currently, there are very few reports in the literature regarding laparoscopic colectomy in the case of solid-organ transplant patients and none concerning a straight laparoscopic colectomy in a liver transplant patient. Case Description: We present a 63-year-old female patient with a history of liver transplantation, who developed a left colon cancer 3 years after surgery. The tumor was located in the sigmoid colon, approximately 20 cm from the anal verge. The serum carcinoembryonic antigen was 4.5 ng/mL and a thoracoabdominal computed tomography scan ruled out metastatic disease. Surgery was scheduled and a laparoscopic left colectomy was successfully performed. The postoperative course was uneventful, and the patient was discharged on postoperative day 3. After a 28-month follow-up, the patient remains free of disease. Discussion: To the best of our knowledge, the present case represents the first reported straight laparoscopic colectomy in a liver transplant recipient. Laparoscopic colectomy for colon cancer in previous liver transplant patients is feasible and may be safely performed in the hands of experienced colorectal surgeons. Due to the known benefits of laparoscopic surgery, this alternative appears to be worthwhile and should be considered in selected liver transplant patients.


Journal of Surgical Oncology | 2006

Prognostic value of E-cadherin, beta-catenin, MMPs (7 and 9), and TIMPs (1 and 2) in patients with colorectal carcinoma†‡

Fernanda Roca; Laura V. Mauro; Ana Morandi; Fernando Bonadeo; Carlos Vaccaro; Guillermo Ojea Quintana; Sergio Specterman; Elisa Bal de Kier Joffé; María Guadalupe Pallotta; Lydia Puricelli; José Lastiri


World Journal of Surgery | 2013

Two-day Hospital Stay After Laparoscopic Colorectal Surgery under an Enhanced Recovery after Surgery (ERAS) Pathway

Gustavo Rossi; Hernán Vaccarezza; Carlos Vaccaro; Ricardo Mentz; Victor Im; Adrian Alvarez; Guillermo Ojea Quintana


International Journal of Colorectal Disease | 2017

Right versus left laparoscopic colectomy for colon cancer: does side make any difference?

Juan Pablo Campana; Pablo Pellegrini; Gustavo Rossi; Guillermo Ojea Quintana; Ricardo Mentz; Carlos Vaccaro

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Mario Benati

Hospital Italiano de Buenos Aires

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Fernando Bonadeo

Hospital Italiano de Buenos Aires

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Gustavo Rossi

Hospital Italiano de Buenos Aires

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Fernando A Bonadeo Lassalle

Hospital Italiano de Buenos Aires

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Victor Im

Hospital Italiano de Buenos Aires

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Ricardo Mentz

Hospital Italiano de Buenos Aires

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Hernán Vaccarezza

Hospital Italiano de Buenos Aires

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Eduardo Mullen

Hospital Italiano de Buenos Aires

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