Analysis of the indications for and results of breast cancer screening by magnetic resonance imaging at a cancer center in Brazil.

Objective: To evaluate the indications for and results of magnetic resonance imaging (MRI) examinations for breast cancer screening at a cancer center in Brazil. Materials and Methods: This was a retrospective observational study, based on electronic medical records, of patients undergoing MRI for breast cancer screening at a cancer center in Brazil. Results: We included 597 patients between 19 and 82 years of age. The main indications for MRI screening were a personal history of breast cancer, in 354 patients (59.3%), a family history of breast cancer, in 102 (17.1%), and a confirmed genetic mutation, in 67 (11.2%). The MRI result was classified, in accordance with the categories defined in the Breast Imaging Reporting and Data System, as benign (category 1 or 2), in 425 patients (71.2%), probably benign (category 3), in 143 (24.0%), or suspicious (category 4 or 5), in 29 (4.9%). On MRI, 11 malignant tumors were identified, all of which were invasive carcinomas. Among those 11 carcinomas, six (54.5%) were categorized as minimal cancers (< 1 cm), and the axillary lymph nodes were negative in 10 (90.9%). The cancer detection rate was 18.4/1,000 examinations, and the positive predictive value for suspicious lesions submitted to biopsy was 37.9%. Conclusion: In our sample, the main indication for breast MRI screening was a personal history of breast cancer. The results indicate that MRI is a highly accurate method for the early detection of breast neoplasms in this population.

Objetivo: Avaliar as indicações e resultados de exames de ressonância magnética (RM) para rastreamento de câncer de mama em um centro oncológico no Brasil. Materiais e Métodos: Estudo observacional, realizado mediante análise retrospectiva de pacientes submetidos a RM das mamas para rastreamento de câncer de mama, por meio de revisão do prontuário eletrônico em um centro oncológico. Resultados: Foram incluídas 597 pacientes com idade variando de 19 a 82 anos. As principais indicações para rastreamento foram história pessoal de câncer de mama em 354 (59,3%) pacientes, história familiar em 102 (17,1%) e mutação genética confirmada em 67 (11,2%). O resultado da RM foi benigno (BI-RADS 1 ou 2) em 425 (71,2%) pacientes, provavelmente benigno (BI-RADS 3) em 143 (24,0%) e suspeito (BI-RADS 4 ou 5) em 29 (4,9%). Foram identificados 11 tumores malignos na RM, todos carcinomas invasivos, porcentagem de cânceres "mínimos" (< 1 cm) de 54,5% e porcentagem de axila negativa de 90,9%. A taxa de detecção de câncer na RM foi 18,4/1000 exames e o valor preditivo positivo para as lesões suspeitas submetidas a biópsia foi 37,9%. Conclusão: A principal indicação para RM de rastreamento na nossa população foi história pessoal de câncer de mama. Os resultados mostraram que a RM constitui um método com alta acurácia para detecção precoce de neoplasias da mama nessa população.

Analysis of the indications for and results of breast cancer screening by magnetic resonance imaging at a cancer center in Brazil / Análise das indicações e resultados da ressonância magnética para rastreamento de câncer de mama em um centro oncológico brasileiro

Abstract Objective: To evaluate the indications for and results of magnetic resonance imaging (MRI) examinations for breast cancer screening at a cancer center in Brazil. Materials and Methods: This was a retrospective observational study, based on electronic medical records, of patients undergoing MRI for breast cancer screening at a cancer center in Brazil. Results: We included 597 patients between 19 and 82 years of age. The main indications for MRI screening were a personal history of breast cancer, in 354 patients (59.3%), a family history of breast cancer, in 102 (17.1%), and a confirmed genetic mutation, in 67 (11.2%). The MRI result was classified, in accordance with the categories defined in the Breast Imaging Reporting and Data System, as benign (category 1 or 2), in 425 patients (71.2%), probably benign (category 3), in 143 (24.0%), or suspicious (category 4 or 5), in 29 (4.9%). On MRI, 11 malignant tumors were identified, all of which were invasive carcinomas. Among those 11 carcinomas, six (54.5%) were categorized as minimal cancers (< 1 cm), and the axillary lymph nodes were negative in 10 (90.9%). The cancer detection rate was 18.4/1,000 examinations, and the positive predictive value for suspicious lesions submitted to biopsy was 37.9%. Conclusion: In our sample, the main indication for breast MRI screening was a personal history of breast cancer. The results indicate that MRI is a highly accurate method for the early detection of breast neoplasms in this population.

Resumo Objetivo: Avaliar as indicações e resultados de exames de ressonância magnética (RM) para rastreamento de câncer de mama em um centro oncológico no Brasil. Materiais e Métodos: Estudo observacional, realizado mediante análise retrospectiva de pacientes submetidos a RM das mamas para rastreamento de câncer de mama, por meio de revisão do prontuário eletrônico em um centro oncológico. Resultados: Foram incluídas 597 pacientes com idade variando de 19 a 82 anos. As principais indicações para rastreamento foram história pessoal de câncer de mama em 354 (59,3%) pacientes, história familiar em 102 (17,1%) e mutação genética confirmada em 67 (11,2%). O resultado da RM foi benigno (BI-RADS 1 ou 2) em 425 (71,2%) pacientes, provavelmente benigno (BI-RADS 3) em 143 (24,0%) e suspeito (BI-RADS 4 ou 5) em 29 (4,9%). Foram identificados 11 tumores malignos na RM, todos carcinomas invasivos, porcentagem de cânceres "mínimos" (< 1 cm) de 54,5% e porcentagem de axila negativa de 90,9%. A taxa de detecção de câncer na RM foi 18,4/1000 exames e o valor preditivo positivo para as lesões suspeitas submetidas a biópsia foi 37,9%. Conclusão: A principal indicação para RM de rastreamento na nossa população foi história pessoal de câncer de mama. Os resultados mostraram que a RM constitui um método com alta acurácia para detecção precoce de neoplasias da mama nessa população.

Prognostic value of response evaluation based on breast MRI after neoadjuvant treatment: a retrospective cohort study.

OBJECTIVE: To investigate the impact of response evaluation after neoadjuvant chemotherapy (NAC) in breast cancer patients, assessed by both magnetic resonance imaging (MRI) and pathology, on disease-free survival (DFS). METHODS: This single-center, retrospective cohort study included consecutive breast cancer patients who underwent NAC and preoperative breast MRI. Resolution of invasive carcinoma in the breast and axilla was defined as complete pathological response (pCR). Radiological complete response (rCR) was defined as the absence of abnormal enhancement in the tumor site. Kaplan-Meier estimator was used to estimate the disease-free survival on 60 months. Cox regression analysis was used to estimate hazard ratio (HR) values. RESULTS: In total, 317 patients were included with a mean age of 47.3 years and a mean tumor size of 39.8 mm. The most common immunophenotype was luminal (44.9%), followed by triple-negative (26.8%). Overall, 126 patients (39.7%) had an rCR, while 119 (37.5%) had pCR; the radiological and pathological responses agreed in 252 cases (79.5%). During follow-up, patients who had rCR and pCR had a better DFS curve compared to patients with non-rCR and non-pCR, while those who had rCR or pCR presented an intermediate curve (Log-rank p = 0.003). Multivariate analysis showed a higher risk of recurrence in patients with non-rCR and non-pCR (HR: 5,626; p = 0.020) and those who had a complete response on MRI or pathology only (HR: 4,369; p = 0.067), when compared to patients with rCR and pCR. CONCLUSIONS: The association of MRI and pathological responses after NAC might better stratify the risk of recurrence and prognosis in breast cancer patients. KEY POINTS: • Association of response evaluation after neoadjuvant chemotherapy by pathology and MRI allows better stratification of prognosis. • Complete response to neoadjuvant chemotherapy on pathology and MRI was related to better disease-free survival. • Complete response on MRI or pathology only had a greater risk of recurrence.

Refinando a avaliação das lesões BI-RADS® 4 na ressonância magnética / Refining the evaluation BI-RADS® 4 in injury in magnetic resonance

Os métodos de imagem são de fundamental importância para o manejo de pacientes com câncer de mama, especialmente no diagnóstico precoce de lesões mamárias não-palpáveis. Os principais exames de imagem utilizados neste contexto são a mamografia (MMG), ultrassonografia (US) e ressonância magnética (RM). Para as lesões classificadas como baixo, médio ou intermediário potencial de malignidade, métodos mais avançados como a RM têm permitido melhores resultados na especificidade para lesões malignas. O objetivo principal deste trabalho foi avaliar a taxa de malignidade e características de imagem das lesões mamárias classificadas na categoria BI-RADS® 4 pela RM, a fim de criar um modelo para subcategorizar estas lesões nas categorias 4A, 4B e 4C, de acordo com o risco de malignidade pelos critérios do Léxico BI-RADS®. Foi realizado um estudo observacional, com a avaliação das lesões mamárias com indicação de biópsia percutânea ou cirúrgica em exames de RM realizados no período de 2016 e 2017 no Departamento de Imagem do A.C.Camargo Cancer Center. Para avaliação da validade diagnóstica o resultado histológico foi considerado comopadrão-ouro e, nos casos negativos para malignidade, foi realizado acompanhamento por pelo menos 2 anos. Foram incluídas 166 pacientes com 199 lesões classificadas com BI-RADS®4. 14 (7,5%) não foram biopsiadas, porém apresentaram estabilidade por pelo menos 2 anos ou não se confirmaram em exames subsequentes, inferindo benignidade. Foram avaliadas por biópsia 185 lesões resultando em 140 (75,6%) lesões benignas e 45 (24,3%) lesões malignas. Apresentaram associação estatisticamente significativa com maior risco de malignidade na análise univariada: composição da mama, realce de fundo do parênquima, morfologia, margens e curva cinética (fases inicial e tardia) das lesões nodulares e na análise multivariada, para os realces nodulares apenas o realce de fundo do parênquima, as margens e a curva cinética (fase inicial) confirmaram significância estatística. Os VPP das classificações subjetiva e objetiva foram, respectivamente, para BI-RADS 4 A 0,0% e 4,3%, 4B 11,8% e 21,4% e 4C 62,2% e 78,9%. Nossos resultados afirmam que a subclassificação pode ajudar a diferenciar as lesões quanto a suspeição de malignidade e demonstrou ser viável, tanto através da avaliação subjetiva dos avaliadores, como através da avaliação objetiva utilizando o modelo desenvolvido a partir do valor preditivo positivo dos diferentes descritores utilizados.

Imaging methods are of fundamental importance for the management of patients with breast cancer, especially in the early diagnosis of non-palpable breast lesions. The main imaging tests used in this context are mammography (MMG), ultrasonography (US) and magnetic resonance imaging (MRI). For lesions classified as low, mild or intermediate malignancy potential, more advanced methods such as MRI have allowed better results in specificity for malignancy. The main objective of this study was to evaluate the malignancy rate and imaging characteristics of breast lesions classified in category BI-RADS® 4 by MRI, in order to create a model to subcategorize these lesions into categories 4A, 4B and 4C, according to the risk of malignancy by the criteria of the BI-RADS® Lexicon. An observational study was carried out, with the evaluation of breast lesions with indication for percutaneous or surgical biopsy in the MRI examination carried out in the period of 2016 and 2017 at the Imaging Department of the ACCamargo Cancer Center. To assess the diagnostic validity, the histological result was considered as the gold standard and in cases negative for malignancy, it was followed for at least 2 years. A total of 166 patients with 199 lesions classified as BI-RADS® 4 were included.14 (7.5%) were not biopsied but were stable for at least 2 years or were not confirmed in subsequent examinations, inferring benignity. 185 lesions were evaluated by biopsy resulting in 140 (75.6%) benign lesions and 45 (24.3%) malignant lesions. They presented a statistically significant association with higher risk of malignancy in the univariate analysis: breast composition, background parenchymal enhancement, morphology, margins and kinetic curve (early and late stages) of nodular lesions and in the multivariate analysis, for nodular enhancements only the enhancement of the parenchyma background, the margins and the kinetic curve (initial phase) confirmed statistical significance. The PPV of the subjective and objective classifications were, respectively, for BI-RADS 4A 0.0% and 4.3%, 4B 11.8% and 21.4% and 4C 62.2% and 78.9%. Our results affirm that the subclassification can help to differentiate the lesions as the suspicion of malignancy and it proved to be feasible, both through the subjective evaluation of the evaluators, as through the objective evaluation using the model developed from the positive predictive value of the different descriptors used.

Multidetector Computed Tomography with Dedicated Protocol for Breast Cancer Locoregional Staging: Feasibility Study.

BACKGROUND: The aim of this study was to demonstrate the feasibility of performing multidetector computed tomography (MDCT) with a dedicated protocol for locoregional staging in breast cancer patients. METHODS: This prospective single-center study included newly diagnosed breast cancer patients submitted to contrast-enhanced chest MDCT and breast magnetic resonance imaging (MRI). MDCT was performed in prone position and using subtraction techniques. Fleiss' Kappa coefficient (K) and intraclass correlation coefficient (ICC) were used to assess agreement between MRI, MDCT, and pathology, when available. RESULTS: Thirty-three patients were included (mean age: 47 years). Breast MRI and MDCT showed at least substantial agreement for evaluation of tumor extension (k = 0.674), presence of multifocality (k = 0.669), multicentricity (k = 0.857), nipple invasion (k = 1.000), skin invasion (k = 0.872), and suspicious level I axillary lymph nodes (k = 0.613). MDCT showed higher number of suspicious axillary lymph nodes than MRI, especially on levels II and III. Both methods had similar correlation with tumor size (MRI ICC: 0.807; p = 0.008 vs. MDCT ICC: 0.750; p = 0.020) and T staging (k = 0.699) on pathology. CONCLUSIONS: MDCT with dedicated breast protocol is feasible and showed substantial agreement with MRI features in stage II or III breast cancer patients. This method could potentially allow one-step locoregional and systemic staging, reducing costs and improving logistics for these patients.

Accuracy of ultrasound-guided core-needle biopsy confronted with pathological findings and comparison of its costs with vacuum-assisted biopsy's costs

Introduction: Breast cancer screening has enhanced early­stage diagnosis by detection of impalpable tumors which require histopathological evaluation. Main percutaneous biopsy types are core-needle biopsy (CNB) and vacuum-assisted biopsy (VAB). CNB is less invasive and related to less bleeding and pain. VAB allows larger tissue samples and permits metal clip placement in biopsy bed for posterior localization in case of surgery. Access to VAB is restricted in Brazil due to its high costs. Objectives: To evaluate the agreement between pathological results of ultrasound (US) guided CNB with metal clip placement and surgery and settle false negative rates (FNR), sensibility, specificity, and accuracy of this method, for breast lesions < 20 mm. Methods: 388 US-guided CNB were retrospectively reviewed. Results: Surgical excision was performed in 317 patients. Overall FNR was 9.8%, (5.2% for lesions 10­20 mm), sensibility 90.2% (94.8% for lesions 10­20 mm), specificity 94.9% (94.1% for lesions 10­20 mm), and accuracy 91.1% (94.7% for lesions 10­20 mm). Cost of VAB varies from 2.2 to 12.5 times US-guided CNB. With metal clip placement, VAB costs 1.95 to 5.2 times US-guided CNB. Conclusions: For lesions that can be identified in US, CNB with metal clip placement has high sensitivity, specificity, and accuracy, as well as low FNR.

Accuracy of ultrasound-guided core-needle biopsy confronted with pathological findings and comparison of its costs with vacuum-assisted biopsy's costs

Introduction: Breast cancer screening has enhanced early­stage diagnosis by detection of impalpable tumors which require histopathological evaluation. Main percutaneous biopsy types are core-needle biopsy (CNB) and vacuum-assisted biopsy (VAB). CNB is less invasive and related to less bleeding and pain. VAB allows larger tissue samples and permits metal clip placement in biopsy bed for posterior localization in case of surgery. Access to VAB is restricted in Brazil due to its high costs. Objectives: To evaluate the agreement between pathological results of ultrasound (US) guided CNB with metal clip placement and surgery and settle false negative rates (FNR), sensibility, specificity, and accuracy of this method, for breast lesions < 20 mm. Methods: 388 US-guided CNB were retrospectively reviewed. Results: Surgical excision was performed in 317 patients. Overall FNR was 9.8%, (5.2% for lesions 10­20 mm), sensibility 90.2% (94.8% for lesions 10­20 mm), specificity 94.9% (94.1% for lesions 10­20 mm), and accuracy 91.1% (94.7% for lesions 10­20 mm). Cost of VAB varies from 2.2 to 12.5 times US-guided CNB. With metal clip placement, VAB costs 1.95 to 5.2 times US-guided CNB. Conclusions: For lesions that can be identified in US, CNB with metal clip placement has high sensitivity, specificity, and accuracy, as well as low FNR.

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.

Intramammary lymph nodes: normal and abnormal multimodality imaging features.

Intramammary lymph nodes (IMLN) are one of the most common benign findings at screening mammography. However, abnormal IMLN features, such as diminished or absent hilum, thickened cortex, not circumscribed margins, increased size or interval change, warrants additional follow-up or pathologic analysis to exclude malignancy. Some benign inflammatory conditions may be associated with imaging-detected suspected abnormal IMLN, such as reactive hyperplasia and silicone-induced lymphadenopathy. In patients with known breast cancer, IMLN are a potential site of locoregional spread, which can change the prognosis and management. In some cases, initial breast carcinomas can also mimic IMLN. Breast radiologists must also be aware of the typical and atypical characteristics of IMLN to suggest further investigation when it is necessary.

CT-guided biopsy of breast lesions: When should it be considered?

Mammography, ultrasound, and magnetic resonance imaging (MRI) are the most commonly used modalities for interventional radiology procedures involving the breast. Computed tomography (CT) is rarely used for breast imaging yet it is able to detect breast lesions and can often provide safe and effective access to breast lesions. The aim of this study was to demonstrate situations in which CT should be considered as an alternative guidance method for the biopsy of breast lesions that are not accessible with conventional imaging modalities.

Ultrasound-guided biopsy of breast calcifications using a new image processing technique: initial experience.

The aim of this paper is to describe the use of a new ultrasound imaging processing technique to guide biopsies of suspicious breast calcifications. We used this technique in 13 patients with suspicious breast calcifications that could not be submitted to stereotactic biopsy. Suspicious calcifications were identified by ultrasound, and the biopsy was successfully performed in all cases. Although mammography continues to be the method of choice for the detection and characterization of microcalcifications, this new technique can be an alternative means of guiding biopsy procedures in selected patients who are not candidates for stereotactic biopsy.

O objetivo deste trabalho é descrever o uso de uma nova técnica de processamento de imagens na ultrassonografia para guiar biópsia de microcalcificações mamárias suspeitas. Utilizamos esta técnica em 13 pacientes que não puderam ser submetidos a biópsia por estereotaxia. As calcificações suspeitas foram identificadas na ultrassonografia e a biópsia foi realizada com sucesso em todos os casos. Apesar de a mamografia ser o método de escolha para detecção e caracterização de microcalcificações, esta técnica pode ser uma alternativa para guiar biópsia em pacientes selecionados em que não foi possível realizar biópsia estereotáxica.

Ultrasound-guided biopsy of breast calcifications using a new image processing technique: initial experience / Biópsia de microcalcificações mamárias guiada por ultrassonografia: experiência inicial

Abstract The aim of this paper is to describe the use of a new ultrasound imaging processing technique to guide biopsies of suspicious breast calcifications. We used this technique in 13 patients with suspicious breast calcifications that could not be submitted to stereotactic biopsy. Suspicious calcifications were identified by ultrasound, and the biopsy was successfully performed in all cases. Although mammography continues to be the method of choice for the detection and characterization of microcalcifications, this new technique can be an alternative means of guiding biopsy procedures in selected patients who are not candidates for stereotactic biopsy.

Resumo O objetivo deste trabalho é descrever o uso de uma nova técnica de processamento de imagens na ultrassonografia para guiar biópsia de microcalcificações mamárias suspeitas. Utilizamos esta técnica em 13 pacientes que não puderam ser submetidos a biópsia por estereotaxia. As calcificações suspeitas foram identificadas na ultrassonografia e a biópsia foi realizada com sucesso em todos os casos. Apesar de a mamografia ser o método de escolha para detecção e caracterização de microcalcificações, esta técnica pode ser uma alternativa para guiar biópsia em pacientes selecionados em que não foi possível realizar biópsia estereotáxica.

Can diffusion-weighted imaging add information in the evaluation of breast lesions considered suspicious on magnetic resonance imaging?

OBJECTIVE: To assess the role of diffusion-weighted imaging (DWI) in the evaluation of breast lesions classified as suspicious on magnetic resonance imaging (MRI), correlating the findings with the results of the histological analysis. MATERIALS AND METHODS: This was a retrospective, descriptive study based on a review of the medical records of 215 patients who were submitted to MRI with DWI before undergoing biopsy at a cancer center. Apparent diffusion coefficient (ADC) values were calculated for each lesion, and the result of the histological analysis was considered the gold standard. RESULTS: The mean age was 49 years. We identified 252 lesions, 161 (63.9%) of which were found to be malignant in the histological analysis. The mean ADC value was higher for the benign lesions than for the malignant lesions (1.50 × 10-3 mm2/s vs. 0.97 × 10-3 mm2/s), the difference being statistically significant (p < 0.001). The ADC cut-off point with the greatest sensitivity and specificity on the receiver operating characteristic curve was 1.03 × 10-3 mm2/s. When the DWI and conventional MRI findings were combined, the accuracy reached 95.9%, with a sensitivity of 95.7% and a specificity of 96.4%. CONCLUSION: The use of DWI could facilitate the characterization of breast lesions, especially those classified as BI-RADS 4, increasing the specificity and diagnostic accuracy of MRI.

OBJETIVO: Avaliar o papel da sequência em difusão na avaliação de lesões mamárias suspeitas na ressonância magnética (RM), correlacionando seus achados com os resultados histológicos. MATERIAIS E MÉTODOS: Foi realizado estudo retrospectivo, descritivo, baseado na análise de prontuários médicos de 215 pacientes que realizaram RM com sequência em difusão e que foram submetidas a biópsia em um centro de referência oncológico. Foi calculado o valor do coeficiente de difusão aparente (ADC ­ apparent diffusion coefficient) para cada lesão e o resultado histológico foi considerado como padrão ouro. RESULTADOS: A idade média das pacientes foi 49 anos. Foram identificadas 252 lesões, e destas, 161 (63,9%) eram lesões malignas na avaliação histológica. A média obtida do valor do ADC nas lesões benignas (1,50 × 10­3 mm2/s) foi superior à média das lesões malignas (0,97 × 10­3 mm2/s), com significância estatística (p < 0,001). O ponto de corte com maior sensibilidade e especificidade pela curva receiver operating characteristic foi 1,03 × 10­3 mm2/s. Com a combinação da difusão com os achados da RM, a acurácia chegou a 95,9%, com sensibilidade de 95,7% e especificidade de 96,4%. CONCLUSÃO: O uso da sequência em difusão pode auxiliar na caracterização das lesões mamárias, principalmente daquelas classificadas como BI-RADS 4, aumentando a especificidade e a acurácia diagnóstica da RM.

Can diffusion-weighted imaging add information in the evaluation of breast lesions considered suspicious on magnetic resonance imaging? / A difusão pode acrescentar informações na avaliação de lesões mamárias suspeitas na ressonância magnética?

Abstract Objective: To assess the role of diffusion-weighted imaging (DWI) in the evaluation of breast lesions classified as suspicious on magnetic resonance imaging (MRI), correlating the findings with the results of the histological analysis. Materials and Methods: This was a retrospective, descriptive study based on a review of the medical records of 215 patients who were submitted to MRI with DWI before undergoing biopsy at a cancer center. Apparent diffusion coefficient (ADC) values were calculated for each lesion, and the result of the histological analysis was considered the gold standard. Results: The mean age was 49 years. We identified 252 lesions, 161 (63.9%) of which were found to be malignant in the histological analysis. The mean ADC value was higher for the benign lesions than for the malignant lesions (1.50 × 10-3 mm2/s vs. 0.97 × 10−3 mm2/s), the difference being statistically significant (p < 0.001). The ADC cut-off point with the greatest sensitivity and specificity on the receiver operating characteristic curve was 1.03 × 10−3 mm2/s. When the DWI and conventional MRI findings were combined, the accuracy reached 95.9%, with a sensitivity of 95.7% and a specificity of 96.4%. Conclusion: The use of DWI could facilitate the characterization of breast lesions, especially those classified as BI-RADS 4, increasing the specificity and diagnostic accuracy of MRI.

Resumo Objetivo: Avaliar o papel da sequência em difusão na avaliação de lesões mamárias suspeitas na ressonância magnética (RM), correlacionando seus achados com os resultados histológicos. Materiais e Métodos: Foi realizado estudo retrospectivo, descritivo, baseado na análise de prontuários médicos de 215 pacientes que realizaram RM com sequência em difusão e que foram submetidas a biópsia em um centro de referência oncológico. Foi calculado o valor do coeficiente de difusão aparente (ADC - apparent diffusion coefficient) para cada lesão e o resultado histológico foi considerado como padrão ouro. Resultados: A idade média das pacientes foi 49 anos. Foram identificadas 252 lesões, e destas, 161 (63,9%) eram lesões malignas na avaliação histológica. A média obtida do valor do ADC nas lesões benignas (1,50 × 10-3 mm2/s) foi superior à média das lesões malignas (0,97 × 10-3 mm2/s), com significância estatística (p < 0,001). O ponto de corte com maior sensibilidade e especificidade pela curva receiver operating characteristic foi 1,03 × 10-3 mm2/s. Com a combinação da difusão com os achados da RM, a acurácia chegou a 95,9%, com sensibilidade de 95,7% e especificidade de 96,4%. Conclusão: O uso da sequência em difusão pode auxiliar na caracterização das lesões mamárias, principalmente daquelas classificadas como BI-RADS 4, aumentando a especificidade e a acurácia diagnóstica da RM.

Breast metastases from extramammary malignancies: multimodality imaging aspects.

Breast metastases from extramammary cancers are rare and usually related to poor prognosis. The extramammary tumours most frequently exhibiting breast metastases are melanoma, lymphomas, ovarian cancer, lung and neuroendocrine tumours, and sarcomas. Owing to the lack of reliable and specific clinical or radiological signs for the diagnosis of breast metastases, a combination of techniques is needed to differentiate these lesions from primary breast carcinoma or even benign breast lesions. Multiple imaging methods may be used to evaluate these patients, including mammography, ultrasound, MRI, CT and positron emission tomography CT. Clinical and imaging manifestations are varied, depend on the form of dissemination of the disease and may mimic primary benign and malignant breast lesions. Haematologically disseminated metastases often develop as a circumscribed mass, whereas lymphatic dissemination often presents as diffuse breast oedema and skin thickening. Unlike primary carcinomas, breast metastases generally do not have spiculated margins, skin or nipple retraction. Microlobulated or indistinct margins may be present in some cases. Although calcifications are not frequently present in metastatic lesions, they occur more commonly in patients with ovarian cancer. Although rare, secondary malignant neoplasms should be considered in the differential diagnosis of breast lesions, in the appropriate clinical setting. Knowledge of the most common imaging features can help to provide the correct diagnosis and adequate therapeutic planning.

Role of magnetic resonance imaging in the planning of breast cancer treatment strategies: comparison with conventional imaging techniques.

OBJECTIVE: To assess the role of magnetic resonance imaging (MRI) in the planning of breast cancer treatment strategies. MATERIALS AND METHODS: The study included 160 women diagnosed with breast cancer, who underwent breast MRI for preoperative staging. Using Pearson's correlation coefficient (r), we compared the size of the primary tumor, as determined by MRI, by conventional imaging (mammography and ultrasound), and in the pathological examination (gold standard). The identification of lesions not identified in previous examinations was also evaluated, as was its influence on treatment planning. RESULTS: The mean age of the patients was 52.2 years (range, 30-81 years), and the most common histological type was invasive ductal carcinoma (in 60.6% of the patients). In terms of the tumor size determined, MRI correlated better with the pathological examination than did mammography (r = 0.872 vs. 0.710) or ultrasound (r = 0.836 vs. 0.704). MRI identified additional lesions in 53 patients (33.1%), including malignant lesions in 20 (12.5%), which led to change in the therapeutic planning in 23 patients (14.4%). CONCLUSION: Breast MRI proved to be more accurate than conventional imaging in determining the dimensions of the main tumor and was able to identify lesions not identified by other methods evaluated, which altered the therapeutic planning in a significant proportion of cases.

OBJETIVO: Avaliar o papel da ressonância magnética (RM) no planejamento terapêutico de pacientes com câncer de mama. MATERIAIS E MÉTODOS: Foram avaliadas 160 mulheres com diagnóstico de câncer de mama submetidas a RM para estadiamento préoperatório. O tamanho do tumor principal avaliado pela RM e pelos exames convencionais (mamografia e ultrassonografia) foi comparado com o exame anatomopatológico (padrão ouro), utilizando o coeficiente de correlação de Pearson (r). Foi avaliada, ainda, a presença de lesões adicionais não identificadas nos exames prévios e sua influência no planejamento terapêutico. RESULTADOS: A idade média das pacientes foi 52,2 anos (variação: 30­81 anos) e o tipo histológico mais comum foi o carcinoma ductal invasivo (60,6%). A medida do tumor na RM teve melhor correlação com o tamanho no exame anatomopatológico, quando comparado com a mamografia (r: 0,872 × 0,710) e com a ultrassonografia (r: 0,836 × 0,704). A RM identificou lesões adicionais em 53 pacientes (33,1%), sendo 20 malignas (12,5%), e modificou o planejamento terapêutico em 23 pacientes (14,4%). CONCLUSÃO: A RM das mamas demonstrou ser mais acurada que os exames convencionais na avaliação das dimensões do tumor principal e foi capaz de identificar lesões adicionais não identificadas pelos outros métodos, que alteraram o planejamento terapêutico em um percentual importante dos casos.