Solitary pulmonary nodule and (18)F-FDG PET/CT. Part 2: accuracy, cost-effectiveness, and current recommendations.

A solitary pulmonary nodule is a common, often incidental, radiographic finding. The investigation and differential diagnosis of solitary pulmonary nodules remain complex, because there are overlaps between the characteristics of benign and malignant processes. There are currently many strategies for evaluating solitary pulmonary nodules. The main objective is to identify benign lesions, in order to avoid exposing patients to the risks of invasive methods, and to detect cases of lung cancer accurately, in order to avoid delaying potentially curative treatment. The focus of this study was to review the evaluation of solitary pulmonary nodules, to discuss the current role of (18)F-fluorodeoxyglucose positron-emission tomography, addressing its accuracy and cost-effectiveness, and to detail the current recommendations for the examination in this scenario.

O nódulo pulmonar solitário corresponde a um achado radiológico comum, cuja detecção ocorre frequentemente de forma incidental. A investigação desta entidade permanece complexa, uma vez que existem sobreposições entre as características dos processos benignos e malignos no seu diagnóstico diferencial. Atualmente, muitas estratégias estão disponíveis para a avaliação do nódulo pulmonar solitário, e o objetivo principal consiste em caracterizar da melhor forma possível as alterações benignas, não expondo os pacientes aos riscos de métodos invasivos, e detectar corretamente os casos de câncer de pulmão, não retardando potencial tratamento curativo. O foco deste estudo é revisar a avaliação do nódulo pulmonar solitário, discutindo o papel atual da tomografia por emissão de pósitrons com 18-fluordesoxiglicose, apresentar sua acurácia e custo-efetividade, bem como salientar as recomendações atuais do exame neste cenário.

Solitary pulmonary nodule and 18F-FDG PET/CT. Part 2: accuracy, cost-effectiveness, and current recommendations / Nódulo pulmonar solitário e 18F-FDG PET/CT. Parte 2: acurácia, custo-efetividade e recomendações atuais

Abstract A solitary pulmonary nodule is a common, often incidental, radiographic finding. The investigation and differential diagnosis of solitary pulmonary nodules remain complex, because there are overlaps between the characteristics of benign and malignant processes. There are currently many strategies for evaluating solitary pulmonary nodules. The main objective is to identify benign lesions, in order to avoid exposing patients to the risks of invasive methods, and to detect cases of lung cancer accurately, in order to avoid delaying potentially curative treatment. The focus of this study was to review the evaluation of solitary pulmonary nodules, to discuss the current role of 18F-fluorodeoxyglucose positron-emission tomography, addressing its accuracy and cost-effectiveness, and to detail the current recommendations for the examination in this scenario.

Resumo O nódulo pulmonar solitário corresponde a um achado radiológico comum, cuja detecção ocorre frequentemente de forma incidental. A investigação desta entidade permanece complexa, uma vez que existem sobreposições entre as características dos processos benignos e malignos no seu diagnóstico diferencial. Atualmente, muitas estratégias estão disponíveis para a avaliação do nódulo pulmonar solitário, e o objetivo principal consiste em caracterizar da melhor forma possível as alterações benignas, não expondo os pacientes aos riscos de métodos invasivos, e detectar corretamente os casos de câncer de pulmão, não retardando potencial tratamento curativo. O foco deste estudo é revisar a avaliação do nódulo pulmonar solitário, discutindo o papel atual da tomografia por emissão de pósitrons com 18-fluordesoxiglicose, apresentar sua acurácia e custo-efetividade, bem como salientar as recomendações atuais do exame neste cenário.

Solitary pulmonary nodule and (18)F-FDG PET/CT. Part 1: epidemiology, morphological evaluation and cancer probability.

Solitary pulmonary nodule corresponds to a common radiographic finding, which is frequently detected incidentally. The investigation of this entity remains complex, since characteristics of benign and malignant processes overlap in the differential diagnosis. Currently, many strategies are available to evaluate solitary pulmonary nodules with the main objective of characterizing benign lesions as best as possible, while avoiding to expose patients to the risks inherent to invasive methods, besides correctly detecting cases of lung cancer so as the potential curative treatment is not delayed. This first part of the study focuses on the epidemiology, the morfological evaluation and the methods to determine the likelihood of cancer in cases of indeterminate solitary pulmonary nodule.

O nódulo pulmonar solitário corresponde a um achado radiológico comum, cuja detecção ocorre frequentemente de forma incidental. A investigação desta entidade permanece complexa, uma vez que existem sobreposições entre as características dos processos benignos e malignos no seu diagnóstico diferencial. Atualmente, muitas estratégias estão disponíveis para a avaliação do nódulo pulmonar solitário, sendo que o objetivo principal consiste em caracterizar da melhor forma possível as alterações benignas, não expondo os pacientes aos riscos de métodos invasivos, e detectar corretamente os casos de câncer de pulmão, não retardando potencial tratamento curativo. Esta primeira parte do estudo tem como foco apresentar a epidemiologia, revisar a avaliação morfológica e demonstrar métodos para estimar a probabilidade de câncer em nódulo pulmonar solitário indeterminado.

Solitary pulmonary nodule and 18F-FDG PET/CT. Part 1: epidemiology, morphological evaluation and cancer probability / Nódulo pulmonar solitário e 18F-FDG PET/CT. Parte 1: epidemiologia, avaliação morfológica e probabilidade de câncer

Abstract Solitary pulmonary nodule corresponds to a common radiographic finding, which is frequently detected incidentally. The investigation of this entity remains complex, since characteristics of benign and malignant processes overlap in the differential diagnosis. Currently, many strategies are available to evaluate solitary pulmonary nodules with the main objective of characterizing benign lesions as best as possible, while avoiding to expose patients to the risks inherent to invasive methods, besides correctly detecting cases of lung cancer so as the potential curative treatment is not delayed. This first part of the study focuses on the epidemiology, the morfological evaluation and the methods to determine the likelihood of cancer in cases of indeterminate solitary pulmonary nodule.

Resumo O nódulo pulmonar solitário corresponde a um achado radiológico comum, cuja detecção ocorre frequentemente de forma incidental. A investigação desta entidade permanece complexa, uma vez que existem sobreposições entre as características dos processos benignos e malignos no seu diagnóstico diferencial. Atualmente, muitas estratégias estão disponíveis para a avaliação do nódulo pulmonar solitário, sendo que o objetivo principal consiste em caracterizar da melhor forma possível as alterações benignas, não expondo os pacientes aos riscos de métodos invasivos, e detectar corretamente os casos de câncer de pulmão, não retardando potencial tratamento curativo. Esta primeira parte do estudo tem como foco apresentar a epidemiologia, revisar a avaliação morfológica e demonstrar métodos para estimar a probabilidade de câncer em nódulo pulmonar solitário indeterminado.

Perfused lung volume to thoracic gas volume ratio (perfused lung fraction) in patients with COPD and in controls.

BACKGROUND: The deterioration of the ventilation-to-perfusion distribution in patients with chronic obstructive pulmonary disease (COPD) reflects structural changes affecting both the airways and the blood vessels. These changes result in lung perfusion abnormalities that may be quantified by lung perfusion single photon emission computed tomography (SPECT). OBJECTIVE: To compare the perfused lung fraction (PLF) in patients with airflow obstruction and controls. METHODS: Fourteen patients with COPD and 21 controls underwent spirometry, whole-body plethysmography, and lung perfusion SPECT. PLF was derived from the ratio of perfused lung volume (measured by SPECT) to thoracic gas volume (measured by whole-body plethysmography). RESULTS: In the whole study sample, there were 18 (51%) women and 17 (49%) men, mean age was 46.2 (±20.3) years, range: 18-80 years). In the COPD group, PLF was 0.74 (±0.08), whereas in the control group PLF was 0.99 (±0.18) (P<0.001). PLF correlated directly with forced expiratory volume in 1 s to forced vital capacity (r=0.597, P<0.001). Perfused lung volume was 3.66 (±0.64) l in the COPD group compared with 2.71 (±0.70) l in the control group (P<0.001). CONCLUSION: The fraction of lung volume receiving blood from the pulmonary artery is reduced in patients with COPD. The degree of underperfusion seems to correlate with the degree of airflow limitation.

Injeção intraoperatória de dextran-500-99m_tecnécio para identificação do linfonodo sentinela em câncer de mama / Intraoperative injection of technetium-99m-dextran 500 for the identification of sentinel lymph node in breast cancer

OBJETIVO: avaliar a eficácia da injeção intraoperatória para identificação do LS em câncer de mama com o uso do Dextran 500-99m-tecnécio (Tc) e analisar o tempo para marcação do linfonodo sentinela (LS) axilar. MÉTODOS: estudo prospectivo realizado entre abril de 2008 e junho de 2009 que incluiu 74 biópsias de LS em pacientes com câncer de mama em estádios T1N0 e T2N0. Após a indução anestésica, injetou-se de 0,5 a 1,5 mCi (18 a 55 MBq) de Dextran 500-99m-Tc filtrado 0,22 µm num volume de 5 mL de acordo com a técnica de injeção subareolar para a biópsia do LS. Após a marcação com o radiofármaco injetou-se 2 mL de azul patente. O tempo entre a injeção e a marcação na região axilar, a contagem com o probe do LS in vivo, ex vivo, background e o número de LS identificados foram documentados. Os dados foram analisados por meio da estatística descritiva pelo programa SPSS, versão 18. RESULTADOS: identificamos o LS em 100 por cento dos casos. A taxa de identificação com o probe foi de 98 por cento (73/74 casos). Um caso (1,35 por cento) estava marcado apenas com o azul. A dose média do radiofármaco aplicada foi 0,97 mCi±0,22. O tempo para marcação na região axilar, após a injeção subareolar, foi de 10,7 minutos (±5,7 min. ). Foram identificados, em média, 1,66 linfonodos marcados com o radioisotopo. CONCLUSÃO: o procedimento para identificação do LS com injeção intraoperatória do radiofármaco é oncologicamente seguro, apresentando conforto ao paciente e agilidade à equipe cirúrgica.

PURPOSE: to determine the efficacy of intraoperative injection of Dextran-500-99m-technetium (Tc) for the identification of the sentinel lymph node (SLN) in breast cancer and analyze time to label the SLN in the axillary region. METHODS: a prospective study between April 2008 and June 2009, which included 74 sentinel lymph node biopsies (SLNB) in patients with breast cancer in stages T1N0 and T2N0. After induction of anesthesia, 0.5 to 1.5 mCi of Dextran-500-99m-Tc filtered 0.22 µm in a volume of 5 mL was injected intraoperative using the subareolar technique for SLNB. After labeling with the radioisotope, 2 mL of patent blue was injected. The time elapsed between injection and the axillary hot spot, the in vivo and ex vivo counts of the hottest nodes, the background count, and the number of SLN identified were documented. Data were analyzed using descriptive statistics with SPSS program, version 18. RESULTS: we identified the SLN in 100 percent of cases. The rate of SLN identification with the probe was 98 percent (73/74 cases). In one case (1.35 percent) the SLN was labeled only with the blue dye. The mean dose of radioisotope injected was 0.97±0.22 mCi. The average time to label the SLN was 10.7 minutes (±5.7 min). We identified on average of 1.66 SLN labeled with the radioisotope. CONCLUSION: the procedure for SLN identification with an intraoperative injection of the radioisotope is oncologically safe and comfortable for the patient, providing agility to the surgical team.

[Intraoperative injection of technetium-99m-dextran 500 for the identification of sentinel lymph node in breast cancer]. / Injeção intraoperatória de dextran-500-99m_tecnécio para identificação do linfonodo sentinela em câncer de mama.

PURPOSE: to determine the efficacy of intraoperative injection of Dextran-500-99m-technetium (Tc) for the identification of the sentinel lymph node (SLN) in breast cancer and analyze time to label the SLN in the axillary region. METHODS: a prospective study between April 2008 and June 2009, which included 74 sentinel lymph node biopsies (SLNB) in patients with breast cancer in stages T1N0 and T2N0. After induction of anesthesia, 0.5 to 1.5 mCi of Dextran-500-99m-Tc filtered 0.22 µm in a volume of 5 mL was injected intraoperative using the subareolar technique for SLNB. After labeling with the radioisotope, 2 mL of patent blue was injected. The time elapsed between injection and the axillary hot spot, the in vivo and ex vivo counts of the hottest nodes, the background count, and the number of SLN identified were documented. Data were analyzed using descriptive statistics with SPSS program, version 18. RESULTS: we identified the SLN in 100% of cases. The rate of SLN identification with the probe was 98% (73/74 cases). In one case (1.35%) the SLN was labeled only with the blue dye. The mean dose of radioisotope injected was 0.97 ± 0.22 mCi. The average time to label the SLN was 10.7 minutes (± 5.7 min). We identified on average of 1.66 SLN labeled with the radioisotope. CONCLUSION: the procedure for SLN identification with an intraoperative injection of the radioisotope is oncologically safe and comfortable for the patient, providing agility to the surgical team.