68Ga-DOTATATE PET/CT versus 111In-octreotide scintigraphy in patients with neuroendocrine tumors: a prospective study.

OBJECTIVE: To compare 68Ga-DOTA-DPhe1,Tyr3-octreotate (68Ga-DOTATATE) positron-emission tomography/computed tomography (PET/CT) findings with those of conventional 111In-octreotide scintigraphy in patients with neuroendocrine tumors (NETs). MATERIALS AND METHODS: This was a single-center prospective study including 41 patients (25 males; mean age, 55.4 years) with biopsy-proven NETs who underwent whole-body 111In-octreotide scintigraphy and whole-body 68Ga-DOTATATE PET/CT. The patients had been referred for tumor staging (34.1%), tumor restaging (61.0%), or response evaluation (4.9%). Images were compared in a patient-by-patient analysis to identify additional lesions, and we attempted to determine the impact that discordant findings had on treatment planning. RESULTS: Compared with 111In-octreotide scintigraphy, 68Ga-DOTATATE PET/CT revealed more lesions, the additional lesions typically being in the liver or bowel. Changes in management owing to the additional information provided by 68Ga-DOTATATE PET/CT occurred in five patients (12.2%), including intermodal changes in three (7.3%) and intramodal changes in two (4.9%). In addition, 68Ga-DOTATATE PET/CT yielded incidental findings unrelated to the primary NET in three patients (7.3%): Hürthle cell carcinoma of the thyroid, bowel non-Hodgkin lymphoma, and a suspicious breast lesion. CONCLUSION: We conclude that 68Ga-DOTATATE PET/CT is superior to conventional 111In-octreotide scintigraphy for the management of NETs because of its ability to determine the extent of the disease more accurately, which, in some cases, translates to changes in the treatment plan.

OBJETIVO: Comparar os achados da PET/CT com 68Ga-DOTATATE em relação aos da cintilografia com 111In-octreotide em pacientes com tumores neuroendócrinos (TNEs). MATERIAIS E MÉTODOS: Estudo prospectivo unicêntrico incluindo 41 pacientes (25 homens; média de idade: 55,4 anos) com TNEs comprovados por biópsia submetidos a cintilografia de corpo inteiro com 111In-octreotide e PET/CT com 68Ga-DOTATATE. Os pacientes incluídos foram encaminhados para estadiamento do tumor (34,1%), reestadiamento (61,0%) ou avaliação da resposta (4,9%). As imagens foram comparadas para identificar lesões adicionais e o impacto dos achados discordantes no planejamento terapêutico. RESULTADOS: Na comparação com a cintilografia com 111In-octreotide, a PET/CT com 68Ga-DOTATATE revelou mais lesões, mais frequentemente localizadas no fígado e intestino. Mudanças no tratamento devidas às informações adicionais reveladas pela PET/ CT ocorreram em 5/41 pacientes (12,2%), incluindo mudanças intermodalidade em três casos (7,3%) e intramodalidade em dois casos (4,9%). A PET/CT também identificou achados incidentais não relacionados ao TNE em 3/41 pacientes (7,3%), incluindo um carcinoma de células de Hürthle da tireoide, um linfoma não Hodgkin de intestino e uma lesão mamária suspeita. CONCLUSÃO: A PET/CT com 68Ga-DOTATATE é superior à cintilografia convencional com 111In-octreotide para o manejo de pacientes com TNEs, em virtude da sua capacidade de detectar a extensão da doença com mais precisão, o que se traduz, em alguns casos, em alterações terapêuticas.

68Ga-DOTATATE PET/CT versus 111In-octreotide scintigraphy in patients with neuroendocrine tumors: a prospective study / PET/CT com 68Ga-DOTATATE versus cintilografia com 111In-octreotide em pacientes com tumores neuroendócrinos: estudo prospectivo

Abstract Objective: To compare 68Ga-DOTA-DPhe1,Tyr3-octreotate (68Ga-DOTATATE) positron-emission tomography/computed tomography (PET/CT) findings with those of conventional 111In-octreotide scintigraphy in patients with neuroendocrine tumors (NETs). Materials and Methods: This was a single-center prospective study including 41 patients (25 males; mean age, 55.4 years) with biopsy-proven NETs who underwent whole-body 111In-octreotide scintigraphy and whole-body 68Ga-DOTATATE PET/CT. The patients had been referred for tumor staging (34.1%), tumor restaging (61.0%), or response evaluation (4.9%). Images were compared in a patient-by-patient analysis to identify additional lesions, and we attempted to determine the impact that discordant findings had on treatment planning. Results: Compared with 111In-octreotide scintigraphy, 68Ga-DOTATATE PET/CT revealed more lesions, the additional lesions typically being in the liver or bowel. Changes in management owing to the additional information provided by 68Ga-DOTATATE PET/CT occurred in five patients (12.2%), including intermodal changes in three (7.3%) and intramodal changes in two (4.9%). In addition, 68Ga-DOTATATE PET/CT yielded incidental findings unrelated to the primary NET in three patients (7.3%): Hürthle cell carcinoma of the thyroid, bowel non-Hodgkin lymphoma, and a suspicious breast lesion. Conclusion: We conclude that 68Ga-DOTATATE PET/CT is superior to conventional 111In-octreotide scintigraphy for the management of NETs because of its ability to determine the extent of the disease more accurately, which, in some cases, translates to changes in the treatment plan.

RESUMO Objetivo: Comparar os achados da PET/CT com 68Ga-DOTATATE em relação aos da cintilografia com 111In-octreotide em pacientes com tumores neuroendócrinos (TNEs). Materiais e Métodos: Estudo prospectivo unicêntrico incluindo 41 pacientes (25 homens; média de idade: 55,4 anos) com TNEs comprovados por biópsia submetidos a cintilografia de corpo inteiro com 111In-octreotide e PET/CT com 68Ga-DOTATATE. Os pacientes incluídos foram encaminhados para estadiamento do tumor (34,1%), reestadiamento (61,0%) ou avaliação da resposta (4,9%). As imagens foram comparadas para identificar lesões adicionais e o impacto dos achados discordantes no planejamento terapêutico. Resultados: Na comparação com a cintilografia com 111In-octreotide, a PET/CT com 68Ga-DOTATATE revelou mais lesões, mais frequentemente localizadas no fígado e intestino. Mudanças no tratamento devidas às informações adicionais reveladas pela PET/ CT ocorreram em 5/41 pacientes (12,2%), incluindo mudanças intermodalidade em três casos (7,3%) e intramodalidade em dois casos (4,9%). A PET/CT também identificou achados incidentais não relacionados ao TNE em 3/41 pacientes (7,3%), incluindo um carcinoma de células de Hürthle da tireoide, um linfoma não Hodgkin de intestino e uma lesão mamária suspeita. Conclusão: A PET/CT com 68Ga-DOTATATE é superior à cintilografia convencional com 111In-octreotide para o manejo de pacientes com TNEs, em virtude da sua capacidade de detectar a extensão da doença com mais precisão, o que se traduz, em alguns casos, em alterações terapêuticas.

False-Positive Uptake in Splenic Hemangioma on 68Ga-PSMA PET/CT Scan for Late Biochemical Recurrence of Prostate Cancer.

ABSTRACT: A 71-year-old man underwent 68Ga-PSMA PET/CT for evaluation of a late biochemical recurrence after radical prostatectomy. An intense PSMA uptake was identified in spleen. Additional evaluation with a contrast-enhanced MRI showed a splenic lesion consistent with splenic hemangioma.

Single Adrenal Metastasis From Prostate Cancer Detected by 68Ga-PSMA PET/CT and Confirmed by Biopsy: A Case Report.

ABSTRACT: This image demonstrates an unusual presentation of an adrenal metastasis from prostate cancer detected by 68Ga-prostate-specific membrane antigen PET/CT and confirmed by biopsy. A 68-year-old man with prostate cancer persisted with elevated levels of prostate-specific antigen after radical prostatectomy. Imaging identified a single abnormal uptake in the left adrenal gland. A biopsy was performed showing a metastatic prostatic adenocarcinoma. The patient received systemic treatment, and his prostate-specific antigen level decreased significantly. Our objective is to illustrate an unusual and single site of prostate cancer metastasis, in which precise histological diagnosis was essential for correct clinical management of the patient.

Evaluation of the clinical use of PET/CT with 68Ga-PSMA for the assessment of biochemical recurrence of low or intermediate-risk prostate cancer.

RATIONALE: 68Ga-prostate-specific membrane antigen positron emission tomography/computed tomography (PET-PSMA) has shown promising performance for the assessment of biochemical recurrence of prostate cancer in high-risk patients, defined by D´Amico et al. criteria. Little evidence for the impact of this diagnostic method for patients at low or intermediate risk, in terms of management and benefits of subsequent treatment, is available. METHODS: Data from 57 patients with low and intermediate-risk prostate cancer and biochemical recurrence underwent PET-PSMA were examined retrospectively. Images were analyzed and findings were compared with clinical data. Indications for the PET-PSMA imaging, study positivity/negativity, lesion locations, Gleason (ISUP) score, prostate-specific antigen (PSA) level on the examination date, postexamination treatment, and management were evaluated. RESULTS: PET-PSMA findings were negative for 28 (49.12%) patients, 11 of whom received salvage radiotherapy (S-RT; with or without HT; PSA levels declined significantly in 10 (90.9%) of these patients compared with levels in those not undergoing S-RT. Positive PET-PSMA findings enabled the accurate identification of patients who benefited from salvage pelvic RT for local disease control and those who responded satisfactorily to systemic treatment. CONCLUSION: PET-PSMA is useful for the assessment of biochemical recurrence in prostate cancer patients with prostate cancer at low and intermediate-risk.

Recurrent diffuse large B-cell lymphoma mimicking primary breast cancer

Breast lymphoma can represent 0.8%­2.2% of extranodal lymphomas and 0.1%­0.5% of primary breast neoplasms. Imaging findings are not specific, and its distinction from primary invasive breast carcinoma should be based on clinical data and histopathological analysis. We present the case of a 62-year-old woman who showed an unusual pattern of recurrent diffuse large B-cell lymphoma (DLBCL) mimicking primary breast cancer on imaging studies, including mammography, ultrasound, magnetic resonance imaging (MRI), and positron emission tomography-computed tomography (PET-CT).

Prognostic role of 18F-FDG PET-CT in the prone position in the evaluation of invasive breast carcinoma

Introduction: The objective of this study was to correlate the features of invasive breast carcinoma in 18F-FDG positron emission tomography/computed tomography with histopathological results, findings from other imaging methods, and survival. Methods: This observational single-center study included patients who underwent staging 18F-FDG positron emission tomography/ computed tomography between September 2012 and April 2019; the results were correlated with the findings of other imaging tests and anatomopathological results. Lesions were evaluated for their maximum standardized uptake value on positron emission tomography/computed tomography performed in the prone position. Tumors were classified into three subtypes (luminal, HER2 and triple-negative) based on immunohistochemical analyses. Results: A total of 125 patients with a mean age of 52 years (24­90 years) were analyzed. The primary tumor showed an increased 18F-FDG concentration on positron emission tomography/computed tomography in 122 (97.6%) patients, with a mean maximum standardized uptake value of 7.15 (1.0­32.9 range). The mean maximum standardized uptake value was higher in the triple-negative subtype (11.4; n=24) than in the luminal (6.2; n=89) and HER2 (5.0; n=9) subtypes (p<0.01). Tumors with more aggressive histological and immunohistochemical characteristics showed higher maximum standardized uptake values. Patients with a standardized uptake value greater than 7 in the primary tumor or greater than 6.7 in the axillary lymph nodes had poor overall survival (p=0.03 and p<0.01, respectively). Conclusions: Our study suggests that the maximum standardized uptake value obtained on positron emission tomography/computed tomography in the prone position may correlate with the tumor immunophenotype and overall survival regardless of the treatments performed, and can be used as a prognostic biomarker in invasive breast carcinoma patients

Diffuse pleural metastases of osteosarcoma detected by bone scan.

Osteosarcoma (OS) is a fast-growing tumor, with a high risk of local recurrence and distant metastases, with the lung and bone being the most common sites of dissemination occurring in approximately 80% of cases. Pleural metastases rarely occurs and the appearance of diffuse pleural thickening with ossification is not usual, with few such cases reported due to the current state-of-art treatment protocols. A 29-year-old woman, diagnosed with a proximal left tibial OS underwent planar and single-photon emission computed tomography/computed tomography bone scan scintigraphy with 99mtechnetium methylene diphosphonate showing bilateral pleural uptake, corresponding to multiple calcified foci of thickening and nodules.

Extrapleural solitary fibrous tumor evidenced by 68Ga-prostate-specific membrane antigen positron emission tomography/computed tomography study in the staging of a high-risk prostate cancer patient.

Positron emission tomography/computed tomography (PET/CT) using 68Ga-labeled prostate-specific membrane antigen (68Ga-PSMA) became an important tool in the prostate cancer (PC) diagnosis. Despite its high sensitivity and specificity, this method may produce false-positive findings, as indicated by previous studies. This case report aims to warn nuclear medicine physicians, oncologists, and urologists about the possibility of false-positive findings using this imaging modality, especially in patients who have already been diagnosed with other malignancies. A 69-year-old man, previously treated for an extrapleural solitary fibrous tumor (ESFT), underwent staging tests after a new diagnosis of high-risk PC. 68Ga-PSMA PET/CT imaging revealed an abnormal uptake in the prostate and in the right humerus. A biopsy was performed, and the pathology showed a lesion consisting of an ESFT metastasis. Diagnostic issues related to 68Ga-PSMA PET/CT imaging should be disseminated to help physicians make appropriate treatment choices for each patient and avoid unnecessary procedures.

18F-FDG PET/CT helps to find occult carcinoma in a patient with multiple breast masses at magnetic resonance imaging / PET/CT com 18F-FDG ajuda a identificar carcinoma oculto em paciente com múltiplos nódulos mamários na ressonância magnética

52-year-old female patient with diagnosis of invasive carcinoma in the left breast and metastatic lymph node in the right axilla. Magnetic resonance imaging showed multiple breast masses, with four previous negative biopsies in the right breast. 18F-FDG positron emission tomography (PET)/computed tomography (CT) was performed in prone position, dedicated to breast evaluation. It showed increased uptake in a mass in the right breast. After PET/magnetic resonance imaging (MRI) fusion and second-look breast ultrasound, this mass was submitted to percutaneous biopsy, which confirmed a second invasive breast carcinoma and changed patients' treatment. This is an example of how PET/MRI dedicated devices can improve the evaluation of selected breast lesions.

Paciente do sexo feminino, de 52 anos, com diagnóstico de carcinoma invasivo na mama esquerda e linfonodo metastático na axila direita. A ressonância magnética mostrou múltiplos nódulos mamários bilaterais, com quatro biópsias anteriores negativas na mama direita. 18F-FDG PET/tomografia computadorizada (CT) foi realizado em decúbito ventral, dedicada à avaliação das mamas, demonstrou aumento da captação em um nódulo na mama direita. Depois de fusão das imagens do PET/CT com a ressonância magnética (RM) e ultrassonografia direcionada, esta lesão foi submetida à biópsia percutânea, que confirmou um segundo carcinoma invasivo na mama direita, alterando o tratamento. Este é um exemplo de como os dispositivos dedicados de PET/RM podem melhorar a avaliação das lesões mamárias selecionadas.

Fibrous dysplasia as a possible false-positive finding in 68Ga-labeled prostate-specific membrane antigen positron emission tomography/computed tomography study in the follow-up of prostate cancer.

Positron emission tomography/computed tomography (PET/CT) using 68Ga-labeled prostate-specific membrane antigen (68Ga-PSMA) has become an important tool in restaging patients with prostate cancer (PCa). Despite its high sensitivity and specificity, this method may produce false-positive findings, as indicated by previous studies. This case report aims to warn nuclear medicine physicians, oncologists, and urologists about the possibility of false-positive findings using this imaging modality, especially when the detected site is unusual for bone metastasis. A 68-year-old man with PCa underwent restaging tests after presenting with increased prostate-specific antigen. 68Ga-PSMA PET/CT imaging revealed abnormal uptake in the left humeral head, which anatomically corresponded to the intramedullary and cortical sclerotic area. A biopsy was performed, and the pathology showed a lesion consisting of hard bone tissue with a small focal spot of fibrous dysplasia. Diagnostic issues related to 68Ga-PSMA PET/CT imaging should be disseminated to help physicians make appropriate treatment choices for each patient.

Development of patient-derived orthotopic xenografts from metastatic colorectal cancer in nude mice.

Liver metastasis is the major cause of death for patients with colorectal cancer. Despite treatment with surgery and chemotherapy, patient outcomes are quite unfavourable. Thus, there is an urgent need to develop new treatment strategies with the associated establishment of good animal models. Metastatic disease can be modelled using patient-derived orthotopic xenografts, which accurately replicate intra-tumoral heterogeneity so that various chemotherapeutic agents can be tested on individual tumours to aid in clinical decision-making. The objective of this study was to develop metastatic colorectal tumours in athymic nude mice by implanting fresh tumour fragments into mouse liver parenchyma. Metastatic tumours were successfully propagated in mice following transplantation from human patients, then serially implanted in second and third-generation mice. Morphologic and immunohistochemical characteristics indicate that xenografts recreate the tumour architecture and mismatch repair gene expression for MLH1, MSH2, MSH1, and PMS2. After tumour implantation during the first passage, the time of tumour growth decreased without loss of tumour identity. Post-transplantation lymphoproliferative disease was observed in one case. This pilot study was successful in establishing the institutional PDX preclinical platform to study new therapeutic strategies, disease progression biomarkers, and treatment responsiveness.

Early metabolic 18F-FDG PET/CT response of locally advanced squamous-cell carcinoma of head and neck to induction chemotherapy: A prospective pilot study.

OBJECTIVE: The objective of this study was to assess the clinical value of 18-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) after the first cycle of induction chemotherapy (IC) in locally advanced squamous cell carcinoma of the head and neck (LASCCHN). METHODS AND FINDINGS: A prospective, single-arm, single center study was performed, with patients enrolled between February 2010 and July 2013.Patients (n = 49) with stage III/IVA-B LASCCHN who underwent IC with taxanes, cisplatin, and fluorouracil were recruited. Staging procedures included loco-regional and chest imaging, endoscopic examination, and PET/CT scan. On day 14 of the first cycle, a second PET/CT scan was performed. Patients with no early increase in regional lymph node maximum 18F-FDG standard uptake value (SUV), detected using 18F-FDG PET/CT after first IC had better progression-free survival (hazard ratio (HR) = 0.18, 95%, confidence interval (CI) 0.056-0.585; p = 0.004) and overall survival (HR = 0.14, 95% CI 0.040-0.498; p = 0.002), and were considered responders. In this subgroup, patients who achieved a reduction of ≥ 45% maximum primary tumor SUV experienced improved progression-free (HR = 0.23, 95% CI 0.062-0.854; p = 0.028) and overall (HR = 0.11, 95% CI 0.013-0.96; p = 0.046) survival. CONCLUSIONS: These results suggest a potential role for early response evaluation with PET/CT examination in patients with LASCCHN undergoing IC. Increased regional lymph node maximum SUV and insufficient decrease in primary tumor uptake predict poorer outcomes.

Computed tomography-guided preoperative localization of musculoskeletal lesions using the ROLL technique.

OBJECTIVE: To describe the preoperative localization of musculoskeletal lesions with the radioguided occult lesion localization (ROLL) technique. MATERIALS AND METHODS: In all cases, computed tomography-guided injection of technetium-99m sulfur colloid was performed, directly into or near the suspicious lesion, up to 36 hours before the surgical procedure. Lesions were detected intraoperatively with a gamma probe. RESULTS: We report the cases of six patients submitted to radioguided surgery, including three patients with bone lesions suspicious for metastasis, two patients suspected of recurrent sarcoma, and one patient with no previous diagnosis who had a nodular lesion on the left leg. Patients tolerated the procedure well, and no complications were associated with the puncture. All marked lesions were easily identified intraoperatively and were excised with clear margins. CONCLUSION: The ROLL technique was effective in the intraoperative localization of occult musculoskeletal lesions, demonstrating that it is a feasible and promising technique for the surgical exploration of selected cases.

Computed tomography-guided preoperative localization of musculoskeletal lesions using the ROLL technique / Localização pré-operatória guiada por tomografia computadorizada de lesões musculoesqueléticas utilizando a técnica ROLL

Abstract Objective: To describe the preoperative localization of musculoskeletal lesions with the radioguided occult lesion localization (ROLL) technique. Materials and Methods: In all cases, computed tomography-guided injection of technetium-99m sulfur colloid was performed, directly into or near the suspicious lesion, up to 36 hours before the surgical procedure. Lesions were detected intraoperatively with a gamma probe. Results: We report the cases of six patients submitted to radioguided surgery, including three patients with bone lesions suspicious for metastasis, two patients suspected of recurrent sarcoma, and one patient with no previous diagnosis who had a nodular lesion on the left leg. Patients tolerated the procedure well, and no complications were associated with the puncture. All marked lesions were easily identified intraoperatively and were excised with clear margins. Conclusion: The ROLL technique was effective in the intraoperative localization of occult musculoskeletal lesions, demonstrating that it is a feasible and promising technique for the surgical exploration of selected cases.

Resumo Objetivo: Descrever a localização pré-operatória de lesões musculoesqueléticas utilizando a técnica radioguided occult lesion localization (ROLL). Materiais e Métodos: Em todos os casos foi realizada administração guiada por tomografia computadorizada de enxofre coloidal marcado com tecnécio-99m, diretamente no interior ou adjacente à lesão suspeita, até 36 horas antes do procedimento cirúrgico. As lesões foram localizadas no intraoperatório utilizando um gama-probe. Resultados: São descritos seis casos de pacientes submetidos a cirurgia radioguiada, sendo três pacientes com lesões ósseas suspeitas para metástase, dois pacientes com sarcoma recidivado e um paciente com lesão nodular na perna esquerda sem diagnóstico prévio. Os pacientes toleraram bem o procedimento e não ocorreram complicações. Todas as lesões foram identificadas adequadamente no intraoperatório e ressecadas com margens livres. Conclusão: A técnica ROLL foi efetiva na localização intraoperatória de lesões musculoesqueléticas ocultas, demonstrando que este procedimento é factível e promissor para facilitar a exploração cirúrgica em casos selecionados.

Detection of distant metastases in patients with locally advanced breast cancer: role of 18F-fluorodeoxyglucose positron emission tomography/computed tomography and conventional imaging with computed tomography scans.

OBJECTIVE: To evaluate positron emission tomography/computed tomography (PET/CT) and conventional imaging tests for the detection of distant metastases in patients with locally advanced breast cancer. MATERIALS AND METHODS: We included 81 patients with breast cancer who had undergone 18F-fluorodeoxyglucose (FDG) PET/CT before treatment. Conventional imaging included the following: bone scintigraphy; chest X-ray (in 14.5%) or CT (in 85.5%); and abdominal ultrasound (in 10.8%), CT (in 87.8%), or magnetic resonance imaging (in 1.4%). Histopathology and clinical/imaging follow-up served as reference. RESULTS: Distant metastases were observed in nine patients (11.1%). On patient-based analysis, conventional imaging identified distant metastases in all 9 patients. In one patient, the initial 18F-FDG PET/CT failed to demonstrate bone metastases that was evident on bone scintigraphy. In two patients, the CT scan failed to show extra-axillary lymph node metastases that were identified on 18F-FDG PET/CT. There was no significant difference between 18F-FDG PET/CT and conventional imaging in terms of their sensitivity for the detection of distant metastases in patients with locally advanced breast cancer. CONCLUSION: This study showed that 18F-FDG PET/CT and conventional imaging with CT scans had similar sensitivity for the diagnosis of distant metastases in patients with locally advanced breast cancer. 18F-FDG PET/CT can add information about extra-axillary lymph node involvements.

OBJETIVO: Avaliar a tomografia por emissão de pósitrons/tomografia computadorizada (PET/TC) e os exames de imagem convencionais na detecção de metástases em pacientes com câncer de mama localmente avançado. MATERIAIS E MÉTODOS: Oitenta e uma pacientes com câncer de mama foram submetidas a PET/TC com 18F-fluordesoxiglicose (18F-FDG) antes do tratamento. Os exames de imagem convencionais incluíram cintilografia óssea, radiografia (14,5%) ou TC (85,5%) do tórax, e ultrassonografia (10,8%), TC (87,8%) ou ressonância magnética (1,4%) do abdome. A histopatologia e o seguimento clínico-imaginológico foram usados como padrão ouro. RESULTADOS: Metástases a distância foram observadas em 9 pacientes (11,1%), sendo identificadas em todas as pacientes pelos exames de imagem convencionais. A PET/TC inicial não demonstrou metástase óssea em uma paciente, que foi identificada na cintilografia óssea. A TC não mostrou metástases em linfonodos extra-axilares, que foram demonstradas na PET/TC, em duas pacientes. Não houve diferença estatisticamente significante entre a PET/TC e os exames de imagem convencionais na detecção de metástases a distância nas pacientes com câncer de mama localmente avançado. CONCLUSÃO: Este estudo mostrou que a PET/TC e os exames de imagem convencionais têm sensibilidade similar no diagnóstico de metástases a distância nas pacientes com câncer de mama localmente avançado. A PET/TC pode adicionar informações sobre o envolvimento de linfonodos extra-axilares.

Detection of distant metastases in patients with locally advanced breast cancer: role of 18F-fluorodeoxyglucose positron emission tomography/computed tomography and conventional imaging with computed tomography scans / Detecção de metástases a distância em pacientes com câncer de mama localmente avançado: papel da tomografia por emissão de pósitrons/tomografia computadorizada com 18F-fluordesoxiglicose e exames de imagem convencional com tomografia computadorizada

Abstract Objective: To evaluate positron emission tomography/computed tomography (PET/CT) and conventional imaging tests for the detection of distant metastases in patients with locally advanced breast cancer. Materials and methods: We included 81 patients with breast cancer who had undergone 18F-fluorodeoxyglucose (FDG) PET/CT before treatment. Conventional imaging included the following: bone scintigraphy; chest X-ray (in 14.5%) or CT (in 85.5%); and abdominal ultrasound (in 10.8%), CT (in 87.8%), or magnetic resonance imaging (in 1.4%). Histopathology and clinical/imaging follow-up served as reference. Results: Distant metastases were observed in nine patients (11.1%). On patient-based analysis, conventional imaging identified distant metastases in all 9 patients. In one patient, the initial 18F-FDG PET/CT failed to demonstrate bone metastases that was evident on bone scintigraphy. In two patients, the CT scan failed to show extra-axillary lymph node metastases that were identified on 18F-FDG PET/CT. There was no significant difference between 18F-FDG PET/CT and conventional imaging in terms of their sensitivity for the detection of distant metastases in patients with locally advanced breast cancer. Conclusion: This study showed that 18F-FDG PET/CT and conventional imaging with CT scans had similar sensitivity for the diagnosis of distant metastases in patients with locally advanced breast cancer. 18F-FDG PET/CT can add information about extra-axillary lymph node involvements.

Resumo Objetivo: Avaliar a tomografia por emissão de pósitrons/tomografia computadorizada (PET/TC) e os exames de imagem convencionais na detecção de metástases em pacientes com câncer de mama localmente avançado. Materiais e métodos: Oitenta e uma pacientes com câncer de mama foram submetidas a PET/TC com 18F-fluordesoxiglicose (18F-FDG) antes do tratamento. Os exames de imagem convencionais incluíram cintilografia óssea, radiografia (14,5%) ou TC (85,5%) do tórax, e ultrassonografia (10,8%), TC (87,8%) ou ressonância magnética (1,4%) do abdome. A histopatologia e o seguimento clínico-imaginológico foram usados como padrão ouro. Resultados: Metástases a distância foram observadas em 9 pacientes (11,1%), sendo identificadas em todas as pacientes pelos exames de imagem convencionais. A PET/TC inicial não demonstrou metástase óssea em uma paciente, que foi identificada na cintilografia óssea. A TC não mostrou metástases em linfonodos extra-axilares, que foram demonstradas na PET/TC, em duas pacientes. Não houve diferença estatisticamente significante entre a PET/TC e os exames de imagem convencionais na detecção de metástases a distância nas pacientes com câncer de mama localmente avançado. Conclusão: Este estudo mostrou que a PET/TC e os exames de imagem convencionais têm sensibilidade similar no diagnóstico de metástases a distância nas pacientes com câncer de mama localmente avançado. A PET/TC pode adicionar informações sobre o envolvimento de linfonodos extra-axilares.

Is early response by (18)F-2-fluoro-2-deoxy-D-glucose positron emission tomography-computed tomography a predictor of long-term outcome in patients with metastatic colorectal cancer?

BACKGROUND: Identify in advance responder patients to chemotherapy in metastatic colorectal cancer (CRC) would allow prompt interruption of ineffective therapies in non-responder patients. Hence, predictive markers are sought in numerous trials to detect responder patients, including tumor shrinkage measured by imaging methods. Usually, Response Evaluation Criteria in Solid Tumors (RECIST) is used to evaluate tumor response in metastatic CRC, but these criteria are questionable with use of biological agents associated to chemotherapy. Our aim was correlate early metabolic response by (18)F-2-fluoro-2-deoxy-D-glucose positron emission tomography-computed tomography ((18)FDG-PET-CT) with long-term outcome in metastatic CRC in first-line therapy. METHODS: We prospectively evaluated 36 patients with metastatic CRC in first-line treatment with 5-fluorouracil, leucovorin (folinic acid), oxaliplatin (FOLFOX) or 5-fluorouracil, leucovorin (folinic acid), irinotecan (FOLFIRI) associated with cetuximab or bevacizumab. (18)FDG-PET-CT was performed at baseline and after two cycles of chemotherapy. The early metabolic response [standardized uptake value (SUV)] was measured to identify responder and non-responder patients and correlated with overall survival (OS) and progression-free survival (PFS). RESULTS: Median age was 58.5 years (range, 41-74 years). PFS was 15.5 months for responder and 13.3 months for non-responder (P=0.42), OS was 55.7 months for responder and not reached for non-responder. There was no correlation between delta-SUV and clinical and pathological variables analyzed. In the subgroup of patients who did not undergo resection of metastasis (45%), PFS was higher for responders (15.3×6.8 months, P=0.02). CONCLUSIONS: According to our findings, early response by (18)FDG-PET-CT was not a predictor of long-term outcome for patients with metastatic CRC treated in the first-line chemotherapy with a monoclonal antibody.