ANGELITA HABR GAMA
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Gastroenterologia, Faculdade de Medicina - Docente
6 resultados
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- Consolidation chemotherapy during neoadjuvant chemoradiation (CRT) for distal rectal cancer leads to sustained decrease in tumor metabolism when compared to standard CRT regimen(2016) HABR-GAMA, Angelita; PEREZ, Rodrigo O.; JULIAO, Guilherme P. Sao; PROSCURSHIM, Igor; FERNANDEZ, Laura M.; FIGUEIREDO, Marleny N.; GAMA-RODRIGUES, Joaquim; BUCHPIGUEL, Carlos A.Background: Neoadjuvant CRT may lead to significant tumor regression in patients with rectal cancer. Different CRT regimens with consolidation chemotherapy may lead to increased rates of complete tumor regression. The purpose of this study was to understand tumor metabolic activity following two different neoadjuvant CRT regimens using sequential PET/CT imaging in two different intervals following RT. Methods: Patients with cT2-4 N0-2 M0 rectal cancer treated by standard CRT (54Gy and 2 cycles of 5FU-based chemotherapy) or extended CRT (54Gy and 6 cycles of 5FU-based chemotherapy) underwent sequential PET/CT imaging at baseline, 6 weeks and 12 weeks from radiation completion. Results: 99 patients undergoing standard CRT were compared to 12 patients undergoing CRT with consolidation chemotherapy. Patients treated with consolidation CRT had increased rates of complete clinical or pathological response (66 % vs. 23 %; p < 0.001). SUVmax variation between baseline and 6 weeks (88 % vs. 63 %; p < 0.001) and between baseline and 12 weeks (90 % vs. 57 %; p < 0.001) were significantly more pronounced among patients undergoing extended CRT with consolidation chemotherapy. An increase in SUVmax between 6 and 12 weeks was observed in 51 % of patients undergoing standard and 18 % of patients undergoing consolidation CRT (p = 0.04). Conclusions: Most of the reduction in tumor metabolism after neoadjuvant CRT occurs within the first 6 weeks from RT completion. In patients undergoing CRT with consolidation chemotherapy, tumors are less likely to regain metabolic activity between 6 and 12 weeks. Therefore, assessment of tumor response may be safely postponed to 12 weeks in patients undergoing extended CRT with consolidation chemotherapy.
conferenceObject CONSOLIDATION CHEMOTHERAPY DURING EXTENDED CRT LEADS TO SUSTAINED DECREASE IN TUMOR METABOLISM WHEN COMPARED TO STANDARD CRT REGIMEN(2014) HABR-GAMA, A.; PEREZ, R.; JULIAO, G. Sao; LYNN, P.; GAMA-RODRIGUES, J.; PROSCURSHIM, I.; BUCHPIGUEL, C.conferenceObject PREDICTIVE FACTORS AT PET/CT FOR COMPLETE RESPONSE AFTER NEOADJUVANT CRT FOR DISTAL RECTAL CANCER - RESULTS FROM A PROSPECTIVE STUDY USING SEQUENTIAL PET/CT(2013) PEREZ, R.; HABR-GAMA, A.; JULIAO, G. Sao; SABBAGH, C.; LYNN, P.; ONO, C.; NAHAS, S.; PROSCURSHIM, I.; BUCHPIGUEL, C.- Predicting complete response to neoadjuvant CRT for distal rectal cancer using sequential PET/CT imaging(2014) PEREZ, R. O.; HABR-GAMA, A.; JULIAO, G. P. Sao; LYNN, P. B.; SABBAGH, C.; PROSCURSHIM, I.; CAMPOS, F. G.; GAMA-RODRIGUES, J.; NAHAS, S. C.; BUCHPIGUEL, C. A.Molecular imaging using positron emission tomography/computerized tomography (PET/CT) may add relevant incremental diagnostic information to standard structural cross-sectional imaging. Such information may allow identification of patients with rectal cancer that are more likely to develop complete tumor regression after neoadjuvant chemoradiation therapy (CRT). The objective of this report was to identify PET/CT features that are associated with a complete response after CRT. 99 cT2-4N0-2M0 distal rectal cancer patients (a parts per thousand currency sign7 cm from anal verge) were included in this prospective single center trial (NCT 00254683). Patients underwent baseline PET/CT followed by 54 Gy and 5-fluorouracil-based neoadjuvant CRT. After completion of therapy, patients underwent 6- and 12-week PET/CT. Clinical assessment of tumor response was performed at 12 weeks and was blinded to radiological information. Patients were treated according to clinical assessment. There were seven patients with a complete pathological response (pCR) and 16 with a complete clinical response (cCR) (23 complete responders). Comparison of pCR exclusively and non-pCR revealed that only baseline primary tumor standard uptake value (SUV) was a significant predictor of response. Comparison of complete responders (pCR or cCR) and non-complete responders showed that depth of rectal wall uptake at baseline PET/CT (p = 0.002) and variation between baseline and 12-week maximum standard uptake value (SUVmax) of primary tumor (p = 0.001) were independent predictors for complete response at multivariate analysis. A decrease > 67 % between baseline and 6-week or 76 % between baseline and 12-week SUVmax were associated with complete response (pCR or cCR; p = 0.02 and p < 0.001, respectively). Positron emission tomography/computerized tomography at baseline, 6 and 12 weeks, may provide information regarding patients with a higher likelihood of developing complete tumor regression following neoadjuvant CRT.
- Accuracy of positron emission tomography/computed tomography and clinical assessment in the detection of complete rectal tumor regression after neoadjuvant chemoradiation Long-Term Results of a Prospective Trial (National Clinical Trial 00254683)(2012) PEREZ, Rodrigo Oliva; HABR-GAMA, Angelita; GAMA-RODRIGUES, Joaquim; PROSCURSHIM, Igor; JULIAO, Guilherme Pagin Sao; LYNN, Patricio; ONO, Carla Rachel; CAMPOS, Fabio Guilherme; SOUSA JR., Afonso Henrique Silva e; IMPERIALE, Antonio Rocco; NAHAS, Sergio Carlos; BUCHPIGUEL, Carlos AlbertoBACKGROUND: Neoadjuvant chemoradiation (CRT) therapy may result in significant tumor regression in patients with rectal cancer. Patients who develop complete tumor regression have been managed by treatment strategies that are alternatives to standard total mesorectal excision. Therefore, assessment of tumor response with positron emission tomography/computed tomography (PET/CT) after neoadjuvant treatment may offer relevant information for the selection of patients to receive alternative treatment strategies. METHODS: Patients with clinical T2 (cT2) through cT4NxM0 rectal adenocarcinoma were included prospectively. Neoadjuvant therapy consisted of 54 grays of radiation and 5-fluorouracil-based chemotherapy. Baseline PET/CT studies were obtained before CRT followed by PET/CT studies at 6 weeks and 12 weeks after the completion of CRT. Clinical assessment was performed at 12 weeks after CRT completion. PET/CT results were compared with clinical and pathologic data. RESULTS: In total, 99 patients were included in the study. Twenty-three patients were complete responders (16 had a complete clinical response, and 7 had a complete pathologic response). The PET/CT response evaluation at 12 weeks indicated that 18 patients had a complete response, and 81 patients had an incomplete response. There were 5 false-negative and 10 false-positive PET/CT results. PET/CT for the detection of residual cancer had 93% sensitivity, 53% specificity, a 73% negative predictive value, an 87% positive predictive value, and 85% accuracy. Clinical assessment alone resulted in an accuracy of 91%. PET/CT information may have detected misdiagnoses made by clinical assessment alone, improving overall accuracy to 96%. CONCLUSIONS: Assessment of tumor response at 12 weeks after CRT completion with PET/CT imaging may provide a useful additional tool with good overall accuracy for the selection of patients who may avoid unnecessary radical resection after achieving a complete clinical response. Cancer 2012;35013511. (C) 2011 American Cancer Society.
- Optimal Timing for Assessment of Tumor Response to Neoadjuvant Chemoradiation in Patients With Rectal Cancer: Do All Patients Benefit From Waiting Longer Than 6 Weeks?(2012) PEREZ, Rodrigo O.; HABR-GAMA, Angelita; JULIAO, Guilherme P. Sao; GAMA-RODRIGUES, Joaquim; SOUSA JR., Afonso H. S.; CAMPOS, Fabio Guilherme; IMPERIALE, Antonio R.; LYNN, Patricio B.; PROSCURSHIM, Igor; NAHAS, Sergio Carlos; ONO, Carla Rachel; BUCHPIGUEL, Carlos AlbertoPurpose: To estimate the metabolic activity of rectal cancers at 6 and 12 weeks after completion of chemoradiation therapy (CRT) by 2-[fluorine-18] fluoro-2-deoxy-D-glucose-labeled positron emission tomography/computed tomography ([18 FDG] PET/CT) imaging and correlate with response to CRT. Methods and Materials: Patients with cT2-4N0-2M0 distal rectal adenocarcinoma treated with long-course neoadjuvant CRT (54 Gy, 5-fluouracil-based) were prospectively studied (ClinicalTrials. org identifier NCT00254683). All patients underwent 3 PET/CT studies (at baseline and 6 and 12 weeks fromCRT completion). Clinical assessment was at 12 weeks. Maximal standard uptakevalue (SUVmax) of the primary tumor wasmeasured and recorded at eachPET/CTstudy after 1 h (early) and3 h (late) from 18 FDGinjection. Patientswith an increase in early SUVmax between 6 and 12 weeks were considered "" bad"" responders and the others as ""good"" responders. Results: Ninety-one patients were included; 46 patients (51%) were ""bad"" responders, whereas 45 (49%) patients were "" good"" responders. "" Bad"" responders were less likely to develop complete clinical response (6.5% vs. 37.8%, respectively; PZ. 001), less likely to develop significant histological tumor regression (complete or near-complete pathological response; 16% vs. 45%, respectively; PZ. 008) and exhibited greater final tumor dimension (4.3cmvs. 3.3cm; PZ. 03). Decrease between early (1 h) and late (3 h) SUVmax at 6-week PET/CTwas a significant predictor of "" good"" response (accuracy of 67%). Conclusions: Patients who developed an increase in SUVmax after 6 weeks were less likely to develop significant tumor downstaging. Early-late SUVmax variation at 6-week PET/CT may help identify these patients and allow tailored selection of CRT-surgery intervals for individual patients. (C) 2012 Elsevier Inc.