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Dive into the research topics where Rodrigo Oliva Perez is active.

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Featured researches published by Rodrigo Oliva Perez.


Annals of Surgery | 2004

Operative Versus Nonoperative Treatment for Stage 0 Distal Rectal Cancer Following Chemoradiation Therapy Long-term Results

Angelita Habr-Gama; Rodrigo Oliva Perez; Wladimir Nadalin; Jorge Sabbaga; Ulysses Ribeiro; Afonso Henrique da Silva e Sousa; Fábio Guilherme Campos; Desidério Roberto Kiss; Joaquim Gama-Rodrigues

Objective:Report overall long-term results of stage 0 rectal cancer following neoadjuvant chemoradiation and compare long-term results between operative and nonoperative treatment. Methods:Two-hundred sixty-five patients with distal rectal adenocarcinoma considered resectable were treated by neoadjuvant chemoradiation (CRT) with 5-FU, Leucovorin and 5040 cGy. Patients with incomplete clinical response were referred to radical surgical resection. Patients with incomplete clinical response treated by surgery resulting in stage p0 were compared to patients with complete clinical response treated by nonoperative treatment. Statistical analysis was performed using χ2, Student t test and Kaplan-Meier curves. Results:Overall and disease-free 10-year survival rates were 97.7% and 84%. In 71 patients (26.8%) complete clinical response was observed following CRT (Observation group). Twenty-two patients (8.3%) showed incomplete clinical response and pT0N0M0 resected specimens (Resection group). There were no differences between patients demographics and tumors characteristics between groups. In the Resection group, 9 definitive colostomies and 7 diverting temporary ileostomies were performed. Mean follow-up was 57.3 months in Observation Group and 48 months in Resection Group. There were 3 systemic recurrences in each group and 2 endorectal recurrences in Observation Group. Two patients in the Resection group died of the disease. Five-year overall and disease-free survival rates were 88% and 83%, respectively, in Resection Group and 100% and 92% in Observation Group. Conclusions:Stage 0 rectal cancer disease is associated with excellent long-term results irrespective of treatment strategy. Surgical resection may not lead to improved outcome in this situation and may be associated with high rates of temporary or definitive stoma construction and unnecessary morbidity and mortality rates.


Journal of Gastrointestinal Surgery | 2006

Patterns of failure and survival for nonoperative treatment of stage c0 distal rectal cancer following neoadjuvant chemoradiation therapy.

Angelita Habr-Gama; Rodrigo Oliva Perez; Igor Proscurshim; Fábio Guilherme Campos; Wladimir Nadalin; Desidério Roberto Kiss; Joaquim Gama-Rodrigues

Neoadjuvant chemoradiation therapy (CRT) is the preferred treatment option for distal rectal cancer. Complete pathological response after CRT has led to the proposal of nonoperative approach as an alternative treatment for highly selected patients with complete clinical response. However, patterns of failure following this strategy remains undetermined. Three hundred sixty-one patients with distal rectal cancer were managed by neoadjuvant CRT including 5-FU, leucovorin, and 5040 cGy. Tumor response assessment was performed at 8 weeks following CRT. Patients with complete clinical response were not immediately operated on and were closely followed. One hundred twenty-two patients were considered to have complete clinical response after the first tumor response assessment. Of these, only 99 patients sustained complete clinical response for at least 12 months and were considered stage c0 (27.4%) and managed nonoperatively. Mean follow-up was 59.9 months. There were 13 (13.1%) recurrences: 5 (5%) endorectal, 7 (7.1%) systemic, and 1 (1%) combined recurrence. All 5 isolated endorectal recurrences were salvaged. Mean recurrence interval was 52 months for local failure and 29.5 months for systemic failure. There were five cancer-related deaths after systemic recurrences. Overall and disease-free 5-year survivals were 93% and 85%. Even though surgery remains the standard treatment for rectal cancer, nonoperative treatment after complete clinical response following neoadjuvant CRT may be safe and associated with good survival rates in a highly selected group of patients. Survival in these patients is significantly affected by systemic failure. Exclusive local failure occurs late after CRT completion and is frequently amenable to salvage therapy.


International Journal of Radiation Oncology Biology Physics | 2014

Local Recurrence After Complete Clinical Response and Watch and Wait in Rectal Cancer After Neoadjuvant Chemoradiation: Impact of Salvage Therapy on Local Disease Control

Angelita Habr-Gama; Joaquim Gama-Rodrigues; Guilherme Pagin São Julião; Igor Proscurshim; Charles Sabbagh; Patricio B. Lynn; Rodrigo Oliva Perez

PURPOSE To review the risk of local recurrence and impact of salvage therapy after Watch and Wait for rectal cancer with complete clinical response (cCR) after chemoradiation therapy (CRT). METHODS AND MATERIALS Patients with cT2-4N0-2M0 distal rectal cancer treated with CRT (50.4-54 Gy + 5-fluorouracil-based chemotherapy) and cCR at 8 weeks were included. Patients with cCR were enrolled in a strict follow-up program with no immediate surgery (Watch and Wait). Local recurrence-free survival was compared while taking into account Watch and Wait strategy alone and Watch and Wait plus salvage. RESULTS 90 of 183 patients experienced cCR at initial assessment after CRT (49%). When early tumor regrowths (up to and including the initial 12 months of follow-up) and late recurrences were considered together, 28 patients (31%) experienced local recurrence (median follow-up time, 60 months). Of those, 26 patients underwent salvage therapy, and 2 patients were not amenable to salvage. In 4 patients, local re-recurrence developed after Watch and Wait plus salvage. The overall salvage rate for local recurrence was 93%. Local recurrence-free survival at 5 years was 69% (all local recurrences) and 94% (after salvage procedures). Thirteen patients (14%) experienced systemic recurrence. The 5-year cancer-specific overall survival and disease-free survival for all patients (including all recurrences) were 91% and 68%, respectively. CONCLUSIONS Local recurrence may develop in 31% of patients with initial cCR when early regrowths (≤ 12 months) and late recurrences are grouped together. More than half of these recurrences develop within 12 months of follow-up. Salvage therapy is possible in ≥ 90% of recurrences, leading to 94% local disease control, with 78% organ preservation.


Diseases of The Colon & Rectum | 2013

Watch and wait approach following extended neoadjuvant chemoradiation for distal rectal cancer: are we getting closer to anal cancer management?

Angelita Habr-Gama; Sabbaga J; Joaquim Gama-Rodrigues; São Julião Gp; Igor Proscurshim; Bailão Aguilar P; Nadalin W; Rodrigo Oliva Perez

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.)


Diseases of The Colon & Rectum | 2010

Complete clinical response after neoadjuvant chemoradiation therapy for distal rectal cancer: characterization of clinical and endoscopic findings for standardization.

Angelita Habr-Gama; Rodrigo Oliva Perez; Gregory Wynn; John H. Marks; Hermann Kessler; Joaquim Gama-Rodrigues

BACKGROUND: Complete tumor regression may develop after neoadjuvant chemoradiation therapy for distal rectal cancer. Studies have suggested that selected patients with complete clinical response may avoid radical surgery and close surveillance may provide good outcomes with no oncologic compromise. However, definition of complete clinical response is often imprecise and may vary between different studies. The aim of this study is to provide a clear definition for a complete clinical response after neoadjuvant chemoradiation therapy in patients with distal rectal cancer in addition to actual endoscopic videos from patients managed nonoperatively. METHODS: Patients with nonmetastatic distal rectal cancer treated by neoadjuvant chemoradiation therapy, including 50.4 Gy and concomitant 5-fluorouracil and leucovorin, were assessed for tumor response at least 8 weeks after chemoradiation therapy completion. Complete and incomplete clinical responses were defined based on clinical and endoscopic findings. Patients with complete clinical response were not immediately operated on and were closely followed. Early and late endoscopic findings were recorded. RESULTS: Definition of a complete clinical response should be based on very strict clinical and endoscopic criteria. The finding of any residual superficial ulceration, irregularity, or nodule should prompt surgical attention, including transanal full-thickness excision or even a radical resection with total mesorectal excision. Standard or incisional biopsies should be avoided in this setting. Complete clinical responders should harbor no more than whitening of the mucosa, teleangiectasia with mucosal integrity to be considered for a nonoperative approach. In the presence of these findings, regularly scheduled reassessments may provide a safe alternative to these patients with early detection of recurrent disease. CONCLUSION: Strict definition of the clinical and endoscopic findings of patients experiencing complete clinical response after neoadjuvant chemoradiation therapy may provide a useful tool for the understanding of outcomes of patients managed with no immediate surgery allowing standardization of classifications and comparison between the experiences of different institutions.


International Journal of Radiation Oncology Biology Physics | 2008

Interval Between Surgery and Neoadjuvant Chemoradiation Therapy for Distal Rectal Cancer: Does Delayed Surgery Have an Impact on Outcome?

Angelita Habr-Gama; Rodrigo Oliva Perez; Igor Proscurshim; Rafael Miyashiro Nunes dos Santos; Desidério Roberto Kiss; Joaquim Gama-Rodrigues; Ivan Cecconello

BACKGROUND The optimal interval between neoadjuvant chemoradiation therapy (CRT) and surgery in the treatment of patients with distal rectal cancer is controversial. The purpose of this study is to evaluate whether this interval has an impact on survival. METHODS AND MATERIALS Patients who underwent surgery after CRT were retrospectively reviewed. Patients with a sustained complete clinical response (cCR) 1 year after CRT were excluded from this study. Clinical and pathologic characteristics and overall and disease-free survival were compared between patients undergoing surgery 12 weeks or less from CRT and patients undergoing surgery longer than 12 weeks from CRT completion and between patients with a surgery delay caused by a suspected cCR and those with a delay for other reasons. RESULTS Two hundred fifty patients underwent surgery, and 48.4% had CRT-to-surgery intervals of 12 weeks or less. There were no statistical differences in overall survival (86% vs. 81.6%) or disease-free survival rates (56.5% and 58.9%) between patients according to interval (< or =12 vs. >12 weeks). Patients with intervals of 12 weeks or less had significantly higher rates of Stage III disease (34% vs. 20%; p = 0.009). The delay in surgery was caused by a suspected cCR in 23 patients (interval, 48 +/- 10.3 weeks). Five-year overall and disease-free survival rates for this subset were 84.9% and 51.6%, not significantly different compared with the remaining group (84%; p = 0.96 and 57.8%; p = 0.76, respectively). CONCLUSIONS Delay in surgery for the evaluation of tumor response after neoadjuvant CRT is safe and does not negatively affect survival. These results support the hypothesis that shorter intervals may interrupt ongoing tumor necrosis.


Diseases of The Colon & Rectum | 2009

Increasing the rates of complete response to neoadjuvant chemoradiotherapy for distal rectal cancer: results of a prospective study using additional chemotherapy during the resting period.

Angelita Habr-Gama; Rodrigo Oliva Perez; Jorge Sabbaga; Wladimir Nadalin; Guilherme Pagin São Julião; Joaquim Gama-Rodrigues

OBJECTIVES: Addition of chemotherapy in the resting period between radiotherapy completion and response assessment during neoadjuvant treatment for distal rectal cancer could potentially increase rates of complete tumor regression. The purpose of this study was to evaluate toxicity rates and the impact of an extended neoadjuvant chemoradiation regimen on complete response rates. METHODS: Thirty-four consecutive patients with nonmetastatic distal rectal cancer were prospectively included. Patients were managed by 5,400 Gy of radiation and 5-fluorouracil/leucovorin-based chemotherapy given for three consecutive days every 21 days for six cycles (three cycles concomitant with radiotherapy). Tumor response assessment was performed at ten weeks from radiation completion. Patients with complete clinical response were strictly monitored and were not immediately operated on. Patients with incomplete clinical response were referred to surgery. RESULTS: Twenty-nine patients had completed 12 months of follow-up and were included in this preliminary analysis. Twenty-eight (97%) successfully completed treatment. Fifteen of 16 patients had Grade III toxicities that were skin-related (93%). Median follow-up was 23 months. Fourteen patients (48%) were considered as complete clinical responders sustained for at least 12 months (median, 24 months) after chemoradiation completion by clinical assessment alone. An additional five patients (17%) were considered as complete responders with ypT0 results after full-thickness local excision. Overall, the complete response rate was 65%. CONCLUSIONS: The addition of chemotherapy during the resting period after neoadjuvant chemoradiation is associated with acceptable toxicity and high tolerability rates. The considerably high rates of complete response in this preliminary series requires further follow-up, but they may provide valuable information for future prospective, randomized trials.


Seminars in Radiation Oncology | 2011

Nonoperative Approaches to Rectal Cancer: A Critical Evaluation

Angelita Habr-Gama; Rodrigo Oliva Perez; Guilherme Pagin São Julião; Igor Proscurshim; Joaquim Gama-Rodrigues

A neoadjuvant multimodality approach with chemoradiation therapy (CRT) is the preferred treatment strategy for most distal rectal cancers. Significant downstaging and complete pathologic response may develop after this strategy, and there is still controversy regarding the management of these patients. In this setting, a nonoperative approach has been suggested in select patients with complete clinical response after thorough clinical, endoscopic, and radiologic assessment. However, the assessment of these patients is not straightforward and remains complex. Available data regarding this approach are limited to a single institutions experience from retrospective analyses. Standardization of the assessment of tumor response and the development of radiological/molecular tools may clarify the role of no immediate surgery in patients with complete clinical response after neoadjuvant CRT. Advances in radiation and medical oncology could potentially lead to significant improvements in complete tumor regression rates, leading to an increase in importance of a minimally invasive approach in patients with rectal cancer.


Diseases of The Colon & Rectum | 2011

Transanal Endoscopic Microsurgery for Residual Rectal Cancer After Neoadjuvant Chemoradiation Therapy Is Associated With Significant Immediate Pain and Hospital Readmission Rates

Rodrigo Oliva Perez; Angelita Habr-Gama; Guilherme Pagin São Julião; Igor Proscurshim; Arceu Scanavini Neto; Joaquim Gama-Rodrigues

BACKGROUND: Transanal endoscopic microsurgery may represent appropriate diagnostic and therapeutic procedure in selected patients with distal rectal cancer following neoadjuvant chemoradiation. Even though this procedure has been associated with low rates of postoperative complications, patients undergoing neoadjuvant chemoradiation seem to be at increased risk for suture line dehiscence. In this setting, we compared the clinical outcomes of patients undergoing transanal endoscopic microsurgery with and without neoadjuvant chemoradiation. METHODS: Thirty-six consecutive patients were treated by transanal endoscopic microsurgery at a single institution. Twenty-three patients underwent local excision after neoadjuvant chemoradiation therapy for rectal adenocarcinoma, and 13 patients underwent local excision without any neoadjuvant treatment for benign and malignant rectal tumors. Chemoradiation therapy included 50.4 to 54Gy and 5-fluorouracil-based chemotherapy. All patients underwent transanal endoscopic microsurgery with primary closure of the rectal defect. Complications (immediate and late) and readmission rates were compared between groups. RESULTS: Overall, median hospital stay was 2 days. Immediate (30-d) complication rate was 44% for grade II/III complications. Patients undergoing neoadjuvant chemoradiation therapy were more likely to develop grade II/III immediate complications (56% vs 23%; P = .05). Overall, the 30-day readmission rate was 30%. Wound dehiscence was significantly more frequent among patients undergoing neoadjuvant chemoradiation therapy (70% vs 23%; P = .03). Patients undergoing neoadjuvant chemoradiation therapy were at significantly higher risk of requiring readmission (43% vs 7%; P = .02). CONCLUSION: Transanal local excision with the use of endoscopic microsurgical approach may result in significant postoperative morbidity, wound dehiscence, and readmission rates, in particular, because of rectal pain secondary to wound dehiscence. In this setting, the benefits of this minimally invasive approach either for diagnostic or therapeutic purposes become significantly restricted to highly selected patients that can potentially avoid a major operation but will still face a significantly morbid and painful procedure.


Diseases of The Colon & Rectum | 2013

Transanal endoscopic microsurgery for residual rectal cancer (ypT0-2) following neoadjuvant chemoradiation therapy: another word of caution.

Rodrigo Oliva Perez; Angelita Habr-Gama; Patricio B. Lynn; Guilherme Pagin São Julião; Romina Bianchi; Igor Proscurshim; Joaquim Gama-Rodrigues

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.

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Patricio B. Lynn

Memorial Sloan Kettering Cancer Center

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