RODRIGO OLIVA PEREZ

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  • article 63 Citação(ões) na Scopus
    Baseline T Classification Predicts Early Tumor Regrowth After Nonoperative Management in Distal Rectal Cancer After Extended Neoadjuvant Chemoradiation and Initial Complete Clinical Response
    (2017) HABR-GAMA, Angelita; JULIAO, Guilherme Pagin Sao; GAMA-RODRIGUES, Joaquim; VAILATI, Bruna Borba; ORTEGA, Cinthia; FERNANDEZ, Laura Melina; ARAUJO, Sergio Eduardo Alonso; PEREZ, Rodrigo Oliva
    BACKGROUND: Selected patients with rectal cancer and complete clinical response after neoadjuvant chemoradiation have been managed nonoperatively with acceptable outcomes. However, approximate to 20% of these patients will develop early tumor regrowth. Identification of these patients could select candidates for more intensive follow-up. OBJECTIVE: The purpose of this study was to investigate the influence of baseline radiological T classification on recurrences after a complete clinical response managed nonoperatively after chemoradiation. DESIGN: This was a retrospective review of a prospective collected database. SETTINGS: The study was conducted at a single center. PATIENTS: Patients with distal rectal cancer (cT2-4N0-2M0) undergoing extended chemoradiation (54 Gy + 5-fluorouracil-based chemotherapy) were eligible. Patients were reassessed for tumor response at 10 weeks after radiation completion. Patients with complete clinical response (clinical, radiological, and endoscopic) were managed nonoperatively and strictly followed. MAIN OUTCOMES MEASURES: Complete clinical response rates, early tumor regrowth rates (<12 mo), local recurrence-free survival, and distant metastases-free survival were measured. RESULTS: A total of 91 consecutive patients with rectal cancer underwent extended chemoradiation. Sixty-one patients developed initial complete clinical response (67%). cT2 patients developed similar initial complete clinical response rates compared with cT3/T4 (72% vs 63%; p = 0.403). Early tumor regrowths were more frequent among baseline cT3/4 when compared with cT2 patients (30% vs 3%; p = 0.007). There were no differences in late local recurrences (p = 0.593) or systemic recurrences (p = 0.387). Local recurrence-free survival was significantly better for cT2 patients at 1 year (96% vs 69%; p = 0.009). After Cox regression analysis, baseline T stage was an independent predictor of improved local recurrence-free survival at 1 year (p = 0.03; OR = 0.09 (95% CI, 0.01-0.81)). LIMITATIONS: This study was limited by its small sample size, retrospective nature, and short follow-up. CONCLUSIONS: cT2 patients who develop complete clinical response after extended chemoradiation managed nonoperatively are less likely to develop early tumor regrowths when compared with cT3/4 patients. cT3/4 patients should undergo more intensive follow-up after a complete clinical response to allow for early detection of early regrowths.
  • article 93 Citação(ões) na Scopus
    Achieving a Complete Clinical Response After Neoadjuvant Chemoradiation That Does Not Require Surgical Resection: It May Take Longer Than You Think!
    (2019) HABR-GAMA, Angelita; JULIAO, Guilherme P. Sao; FERNANDEZ, Laura M.; VAILATI, Bruna B.; ANDRADE, Andres; ARAUJO, Sergio E. A.; GAMA-RODRIGUES, Joaquim; PEREZ, Rodrigo O.
    BACKGROUND: Patients with rectal cancer who achieve complete clinical response after neoadjuvant chemoradiation have been managed by organ-preserving strategies and acceptable long-term outcomes. Controversy still exists regarding optimal timing for the assessment of tumor response after neoadjuvant chemoradiation. OBJECTIVE: The purpose of this study was to estimate the time interval for achieving complete clinical response using strict endoscopic and clinical criteria after a single neoadjuvant chemoradiation regimen. DESIGN: This was a retrospective review of consecutive patients managed by 54-Gy and consolidation 5-fluorouracil-based chemotherapy. Assessment of response was performed at 10 weeks after radiation. Patients with suspected complete clinical response were offered watch-and-wait strategy and reassessment every 6 to 8 weeks until achievement of strict criteria of complete clinical response or overt residual cancer. SETTINGS: This study was conducted at a single tertiary care center. PATIENTS: Patients with complete clinical response who underwent a successful watch-and-wait strategy until last follow-up were eligible. Dates of radiation completion and achievement of strict endoscopic and clinical criteria (mucosal whitening, teleangiectasia, and no ulceration or irregularity) were recorded. Patients with incomplete response or with initial complete clinical response followed by local recurrence or regrowth were excluded. MAIN OUTCOMES MEASURES: The distribution of time intervals between completion of radiation and achievement of strict complete clinical response was measured. Patients who achieved early complete clinical response (<= 16 wk) were compared with late complete clinical response (>16 wk). RESULTS: A total of 49 patients achieved complete clinical response and were successfully managed nonoperatively. A median interval of 18.7 weeks was observed for achieving strict complete clinical response. Only 38% of patients achieved complete clinical response between 10 and 16 weeks from radiation completion. Patients with earlier cT status (cT2/T3a) achieved a complete clinical response significantly earlier when compared with those patients with more advanced disease (T3b-d/4; 19 vs 26 wk; p = 0.03). LIMITATIONS: This was a retrospective study with a small sample size. CONCLUSIONS: Assessment at 10 to 16 weeks may detect a minority of patients who achieve complete clinical response without additional recurrence after neoadjuvant chemoradiation. Patients suspected for a complete clinical response should be considered for reassessment beyond 16 weeks before definitive management when considered for a watch and wait strategy. See Video Abstract at http://links.lww.com/DCR/A901.
  • article 1 Citação(ões) na Scopus
    Putting down the scalpel in rectal cancer management - a historical perspective
    (2018) PEREZ, R. O.; HABR-GAMA, A.
    The surgical management of rectal cancer has evolved from a disease without any possibility of cure in the early 1700s where surgical management consisted of the palliative drainage of disease related abscesses to the present day where surgical cure is not only possible but also possible with sphincter or even organ preservation. Prof Habr-Gama's lecture describes the evolution of the surgical management of rectal cancer and the current focus on organ preservation.
  • 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 54 Citação(ões) na Scopus
    Transanal Endoscopic Microsurgery (TEM) Following Neoadjuvant Chemoradiation for Rectal Cancer: Outcomes of Salvage Resection for Local Recurrence
    (2016) PEREZ, Rodrigo Oliva; HABR-GAMA, Angelita; JULIAO, Guilherme Pagin Sao; PROSCURSHIM, Igor; FERNANDEZ, Laura Melina; AZEVEDO, Rafael Ulysses de; VAILATI, Bruna B.; FERNANDES, Felipe Alexandre; GAMA-RODRIGUES, Joaquim
    Transanal endoscopic microsurgery (TEM) has been considered an alternative for selected patients with rectal cancer following neoadjuvant chemoradiation (CRT). Immediate total mesorectal completion for all patients with unfavorable pathological features would result in unnecessary protectomies in a significant proportion of patients. Instead, salvage total mesorectal excision (TME) could be restricted for patients developing local recurrence. The aim of the present study is to determine oncological outcomes of salvage resection for local recurrences following CRT and TEM. Consecutive patients undergoing TEM following neoadjuvant CRT for rectal cancer were reviewed. Patients with ""near"" complete response to CRT (a parts per thousand currency sign3 cm; ycT1-2N0) were offered TEM. Salvage surgery was attempted in the event of a local recurrence. A total of 53 patients were managed by CRT followed by TEM. Unfavorable pathological features were present in 36 patients (68 %). None of the patients underwent immediate completion TME. There were 12 patients who developed local recurrence resulting in a 2-year local recurrence-free survival of 77 % (95 % CI, 53-100 %). Of these patients, 9 developed exclusively local recurrences, and all had at least 1 unfavorable pathological feature in the specimen after TEM (100 %). Eight patients (8 of 9) underwent salvage resection (abdominoperineal resection [APR] in 87 %) with CRM+ in 7 of 8 patients (87 %). Four patients developed local re-recurrence after a median 36 months of follow-up. The 2-year local re-recurrence free survival was 60 %. Salvage resection for local recurrence following CRT and TEM is associated with high rates of R1 resection (CRM+) and local re-recurrence. Immediate completion of TME should be considered for patients with unfavorable pathological features after TEM.
  • 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 0 Citação(ões) na Scopus
    Time to rethink transanal endoscopic microsurgery for rectal cancer after neoadjuvant chemoradiation for highly selected patients
    (2017) PEREZ, Rodrigo Oliva; JULIAO, Guilherme Pagin Sao; VAILATI, Bruna Borba
  • article 0 Citação(ões) na Scopus
    Session 4: Trying to augment response with chemotherapy: a triumph of hope over experience?
    (2018) BATTERSBY, N. J.; PEREZ, R. O.; BAXTER, N.; MORAN, B.; BROWN, G.
    As part of an approach to improve tumour regression and increase the proportion of patients with complete clinical and radiological response, Dr Perez reviews the methods and evidence base for augmenting therapy and thus augmenting response rates preoperatively. Much of the data reviewed were in the context of patients undergoing a watch-and-wait approach for rectal cancer after initial treatment with chemoradiotherapy.
  • article 98 Citação(ões) na Scopus
    Impact of Organ-Preserving Strategies on Anorectal Function in Patients with Distal Rectal Cancer Following Neoadjuvant Chemoradiation
    (2016) HABR-GAMA, Angelita; LYNN, Patricio B.; JORGE, J. Marcio N.; JULIAO, Guilherme P. Sao; PROSCURSHIM, Igor; GAMA-RODRIGUES, Joaquim; FERNANDEZ, Laura M.; PEREZ, Rodrigo O.
    BACKGROUND: Organ-preserving strategies have been considered for patients with distal rectal cancer and complete or near-complete response to neoadjuvant chemoradiation to avoid the functional consequences of radical surgery. Transanal endoscopic microsurgery and no immediate surgery (watch and wait) have been considered in selected patients. OBJECTIVE: The aim of this study is to compare anorectal function following these 2 organ-preserving strategies (transanal endoscopic microsurgery and watch and wait) for rectal cancer with complete or near-complete response to neoadjuvant chemoradiation. DESIGN: This study is based on the comparison of prospectively collected data. SETTINGS: This study was conducted at a single center. PATIENTS: Consecutive patients with distal rectal cancer undergoing neoadjuvant chemoradiation (50.4-54 Gy and 5-fluorouracil-based chemotherapy) were prospectively studied. Patients with complete clinical response were managed by watch and wait. Patients with near-complete response (<= 3 cm, ycT1-2N0) were managed by transanal endoscopic microsurgery. MAIN OUTCOME MEASURES: Functional outcomes were determined by anorectal manometry and Fecal Incontinence Index and Quality of Life assessment. RESULTS: Two groups of patients were included in the study. Twenty-nine patients with near-complete response undergoing transanal endoscopic microsurgery and 53 with complete response after watch and wait were assessed. Baseline features were similar between groups. Patients undergoing transanal endoscopic microsurgery had worse resting/squeeze pressures (p = 0.004) and rectal capacity (p = 0.002). In addition, their incontinence scores (2.3 vs 6.5; p < 0.001) and quality-of-life questionnaire responses (in all domains; p <= 0.01) were significantly worse in comparison with patients undergoing watch and wait. LIMITATIONS: This study was limited by the small sample size and the absence of baseline anorectal function information. CONCLUSIONS: Nonoperative management of patients with complete clinical response following chemoradiation results in better anorectal function in comparison with patients with near-complete response managed by transanal endoscopic microsurgery. In the absence of clinically detectable residual cancer, this latter approach may result in significant worsening of anorectal function.
  • article 30 Citação(ões) na Scopus
    Semiquantitative Volumetry by Sequential PET/CT May Improve Prediction of Complete Response to Neoadjuvant Chemoradiation in Patients With Distal Rectal Cancer
    (2016) ANJOS, Dalton A. dos; PEREZ, Rodrigo O.; HABR-GAMA, Angelita; JULIAO, Guilherme P. Sao; VAILATI, Bruna B.; FERNANDEZ, Laura M.; SOUSA, Joao B. de; BUCHPIGUEL, Carlos A.
    BACKGROUND: Previous studies using PET/CT imaging have failed to accurately identify complete responders to neoadjuvant chemoradiation among patients with rectal cancer. The use of metabolic parameters alone or imprecise delineation of baseline and residual tumor volumes may have contributed for these disappointing findings. OBJECTIVE: The purpose of this study was to determine the accuracy of complete response identification in rectal cancer after neoadjuvant chemoradiation by sequential PET/CT imaging with a decrease in tumor metabolism and volume using optimal tumor volume delineation. DESIGN: This was a retrospective comparison of prospectively collected data from a clinical trial (National Clinical Trial 00254683). SETTINGS: The study was conducted at a single research center. PATIENTS: Ninety patients with cT2-4N0-2M0 distal rectal cancer underwent sequential PET/CT at baseline and 12 weeks after neoadjuvant chemoradiation. Quantitative metabolic analysis (median and maximal standard uptake values), volumetric estimates (metabolic tumor volume), and composite estimates incorporating volume and quantitative data (total lesion glycolysis) were compared for the assessment of response to neoadjuvant chemoradiation using receiver operating characteristic curves. Individual standard uptake value thresholds were used according to response to neoadjuvant chemoradiation to match metabolic activity and optimize volume delineation. MAIN OUTCOME MEASURES: The accuracy of complete response identification by multiple volumetric and metabolic parameters using sequential PET/CT imaging was measured. RESULTS: Variation in total lesion glycolysis between baseline and 12-week PET/CT scans was associated with the best area under the curve (area under the curve = 0.81 (95% CI, 0.69-0.92)) when compared with standard uptake value or metabolic tumor volume for the identification of a complete responder. Patients with a >= 92% decrease in total lesion glycolysis between baseline and 12-week PET/CT scan had a 90% chance to harbor complete response. LIMITATIONS: This study was limited by its lack of interobserver agreement analysis. CONCLUSIONS: PET/CT scan using volume and metabolic estimates with individual standard uptake value thresholds for volume determination may provide a useful tool to predict response to neoadjuvant chemoradiation in distal rectal cancer.