RODRIGO OLIVA PEREZ

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25
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  • article 378 Citação(ões) na Scopus
    Watch and Wait Approach Following Extended Neoadjuvant Chemoradiation for Distal Rectal Cancer: Are We Getting Closer to Anal Cancer Management?
    (2013) HABR-GAMA, Angelita; SABBAGA, Jorge; GAMA-RODRIGUES, Joaquim; JULIAO, Guilherme P. Sao; PROSCURSHIM, Igor; AGUILAR, Patricia Bailao; NADALIN, Wladimir; PEREZ, Rodrigo O.
    BACKGROUND: No immediate surgery (Watch and Wait) has been considered in select patients with complete clinical response after neoadjuvant chemoradiation to avoid postoperative morbidity and functional disorders after radical surgery. OBJECTIVE: The purpose of this study was to demonstrate the long-term results of patients who had a complete clinical response following an alternative chemoradiation regimen and were managed nonoperatively. DESIGN: This is a prospective study. SETTINGS: This study was conducted at a single center. PATIENTS: Seventy consecutive patients with T2-4N0-2M0 distal rectal cancer were studied. Neoadjuvant chemoradiotherapy included 54 Gy and 5-fluorouracil/leucovorin delivered in 6 cycles every 21 days. Patients were assessed for tumor response at 10 weeks from radiation completion. Patients with incomplete clinical response were referred to immediate surgery. Patients with complete clinical response were not immediately operated on and were monitored. MAIN OUTCOME MEASURES: The primary outcomes measured were the initial complete clinical response rates after 10 weeks and the sustained complete clinical response rates after 12 months from chemoradiotherapy. RESULTS: One patient died during chemoradiotherapy because of cardiac complications. Forty-seven (68%) patients had initial complete clinical response. Of these, 8 developed local regrowth within the first 12 months of follow-up (17%). Thirty-nine sustained complete clinical response at a median follow-up of 56 months (57%). An additional 4 patients (10%) developed late local recurrences (>12 months of follow-up). Overall, 35 patients never underwent surgery (50%). LIMITATIONS: This study is limited by the short follow-up and small sample size. CONCLUSION: Extended chemoradiation therapy with additional chemotherapy cycles and 54 Gy of radiation may result in over 50% of sustained (>12 months) complete clinical response rates that may ultimately avoid radical rectal resection. Local failures occur more frequently during the initial 12 months of follow-up in up to 17% of cases, whereas late recurrences are less common but still possible, leading to 50% of patients who never required surgery. Strict follow-up may allow salvage therapy in the majority of these patients (see Video, Supplemental Digital Content 1, http://links.lww.com/DCR/A113.)
  • article 105 Citação(ões) na Scopus
    Transanal Endoscopic Microsurgery for Residual Rectal Cancer (ypT0-2) Following Neoadjuvant Chemoradiation Therapy: Another Word of Caution
    (2013) PEREZ, Rodrigo Oliva; HABR-GAMA, Angelita; LYNN, Patricio Bernardo; JULIAO, Guilherme Pagin Sao; BIANCHI, Romina; PROSCURSHIM, Igor; GAMA-RODRIGUES, Joaquim
    BACKGROUND: Significant tumor downstaging among patients with rectal cancer following neoadjuvant chemoradiation has raised the issue of offering patients with small residual cancers restricted to the bowel wall an alternative treatment strategy to total mesorectal excision. Transanal endoscopic microsurgery may allow proper primary tumor resection with promising oncological outcomes, less postoperative morbidity, and minimal long-term sexual, urinary, and fecal continence disorders in comparison with radical resection. OBJECTIVE: The aim of this study was to determine the oncological outcomes of patients with residual rectal cancers restricted to the rectal wall (ypT0-2) following neoadjuvant chemoradiation and transanal endoscopic microsurgery. DESIGN: This study considered a prospective cohort of patients with residual rectal cancers following neoadjuvant chemoradiation treated by transanal endoscopic microsurgery and no additional systemic therapy. SETTINGS: This study was a single-institution experience. PATIENTS: Patients with adenocarcinoma of the rectum located no more than 7 cm from the anal verge and endorectal ultrasound-or magnetic resonance-staged cT2-4N0-2M0 treated by neoadjuvant chemoradiation (50.4-54 Gy and 5-fluorouracil-based chemotherapy) were eligible for the study. Patients with small residual tumors (<= 3 cm) radiologically staged ycT0-2N0 were treated by transanal endoscopic microsurgery. INTERVENTIONS: Transanal endoscopic microsurgery was performed. MAIN OUTCOME MEASURES: The primary outcome measured was local recurrence. RESULTS: Of the 27 patients treated by transanal endoscopic microsurgery, 3 had ypT0, 6 had ypT1, and 18 had ypT2 cancers. All patients underwent R0 transanal endoscopic microsurgery excision. Local recurrence was observed in 4 (15%) patients after a median follow-up of 15 months. Only lymphovascular invasion was an independent predictive factor for local failure (p = 0.04). Tumor size, ypT status, T-status downstaging, lateral/radial margins, and tumor regression grade were not predictors of local failure. LIMITATIONS: This study was limited by the small sample size and limited follow-up. CONCLUSIONS: A local failure rate of 15% after transanal endoscopic microsurgery for patients with residual rectal cancers restricted to the bowel wall (ypT0-2) may limit the indication of this procedure to highly selected patients as an alternative to standard radical total mesorectal excision.
  • article 22 Citação(ões) na Scopus
    Is Tailoring Treatment of Rectal Cancer the Only True Benefit of Long-Course Neoadjuvant Chemoradiation?
    (2013) HABR-GAMA, Angelita; GAMA-RODRIGUES, Joaquim; PEREZ, Rodrigo Oliva
  • article 11 Citação(ões) na Scopus
    Clinical relevance of positron emission tomography/computed tomography-positive inguinal nodes in rectal cancer after neoadjuvant chemoradiation
    (2013) PEREZ, R. O.; HABR-GAMA, A.; JULIAO, G. P. Sao; PROSCURSHIM, I.; ONO, C. R.; LYNN, P.; AGUILAR, P. Bailao; NAHAS, S. C.; GAMA-RODRIGUES, J.; BUCHPIGUEL, C. A.
    Aim Inguinal nodes may be a possible route for lymphatic spread in patients with distal rectal cancer. The outcome was examined for patients with distal rectal cancer undergoing neoadjuvant chemoradiation (CRT) and having 2-fluorine-18-fluoro-2-deoxy-d-glucose (FDG)-avid inguinal nodes using positron emission tomography/computed tomography (PET/CT) imaging. Method Ninety-nine consecutive patients with cT2-4N0-2M0 distal rectal adenocarcinoma were enrolled in a clinical trial (NCT00254683) and underwent baseline PET/CT followed by 54Gy and 5-fluorouracil-based CRT. After CRT, patients underwent 6- and 12-week PET/CT. Patients with positive inguinal node uptake were compared with patients with negative uptake. The inguinal region was not included in the field of radiation therapy. Results Seventeen (17%) patients had baseline positive inguinal node FDG uptake. They were more likely to have the tumour closer to the anal verge (2.0 vs 4.2cm; P=0.001). Of these, eight (47%) demonstrated a positive inguinal uptake at PET/CT after 12weeks from CRT. Patients with inguinal node FDG uptake after CRT (positive PET at baseline and 12weeks) had a significantly worse 3-year overall and disease-free survival (P=0.02 and P=0.03). After a median follow-up period of 22months, none of these patients had developed inguinal recurrence. Conclusion Uptake of inguinal nodes at PET/CT may be present in up to 17% of patients with distal rectal cancer, particularly with ultra-low tumours. Nearly half of these nodes no longer show uptake after CRT despite the groin area not being included in the radiation field. Persistence of inguinal node uptake 12weeks after CRT completion may be a marker for worse oncological outcome.
  • article 60 Citação(ões) na Scopus
    Strategies to improve clinical research in surgery through international collaboration
    (2013) SOREIDE, Kjetil; ALDERSON, Derek; BERGENFELZ, Anders; BEYNON, John; CONNOR, Saxon; DECKELBAUM, Dan L.; DEJONG, Cornelis H.; EARNSHAW, Jonathan J.; KYAMANYWA, Patrick; PEREZ, Rodrigo O.; SAKAI, Yoshiharu; WINTER, Desmond C.
    More than 235 million patients undergo surgery every year worldwide, but less than 1% are enrolled in surgical clinical trials-few of which are international collaborations. Several levels of action are needed to improve this situation. International research collaborations in surgery between developed and developing countries could encourage capacity building and quality improvement, and mutually enhance care for patients with surgical disorders. Low-income and middle-income countries increasingly report much the same range of surgical diseases as do high-income countries (eg, cancer, cardiovascular disease, and the surgical sequelae of metabolic syndrome); collaboration is therefore of mutual interest. Large multinational trials that cross cultures and levels of socioeconomic development might have faster results and wider applicability than do single-country trials. Surgeons educated in research methods, and aided by research networks and trial centres, are needed to foster these international collaborations. Barriers to collaboration could be overcome by adoption of global strategies for regulation, health insurance, ethical approval, and indemnity coverage for doctors.