Chest case of the day. Bronchoalveolar carcinoma of the lung

Classification, staging and prognosis of lung cancer

Lung cancer has increased in incidence throughout the twentieth century and is now the most common cancer in the Western World. It has a poor prognosis, only 10-15% of patients survive 5 years or longer. Outcome is dependent on clinical stage and cancer cell type. Lung cancer is broadly subclassified on the basis of histological features into squamous cell carcinoma, adenocarcinoma, large cell carcinoma and small cell carcinoma. The histopathological type of lung cancer correlates with tumour behaviour and prognosis. Staging based on prognosis is essential in clinical trials comparing different management strategies, and enables universal communication regarding the efficacy of different treatments in specific patient groups. The anatomic extent of disease determined either preoperatively using imaging supplemented by invasive procedures such as mediastinoscopy, and anterior mediastinotomy or following resection are described according to the T-primary tumour, N-regional lymph nodes, M-distant metastasis classification. The International System for Staging Lung Cancer attempts to group together patients with similar prognosis and treatment options. Various combinations of T, N, and M define different clinical or surgical-pathological stages (IA-IV) characterised by different survival characteristics. Refinements in staging based on imaging findings have enabled clinical staging to more accurately reflect the surgical-pathological stage and therefore more accurately predict prognosis. Recent advances including the use of positron emission tomography in combination with conventional staging promises to increase the accuracy of staging and therefore to reduce the number of invasive staging procedures and inappropriate thoracotomies.

Evaluation of the clonality of multilobar bronchioloalveolar carcinoma of the lung: case report

A case of multilobar bronchioloalveolar carcinoma (BAC) is reported. To investigate the clonality of BAC, immunohistochemical staining as well as genetic analysis were performed. To investigate point mutations of the p53 gene, we used the polymerase chain reaction and fluorescence-based single strand conformation polymorphism analysis method. The BAC tissues of the right upper lobe, right lower lobe, and the other lobes were considered to be multiclonal. This case suggests that multilobar BAC might occur with multiclonality.

Magnetic resonance imaging of bronchioloalveolar carcinoma

The purpose of this study is to describe the magnetic resonance (MR) features of bronchioloalveolar carcinoma. MR examinations of 18 patients with proven bronchioloalveolar carcinoma were reviewed. Detection at computed tomography (CT) and pathologic confirmation were the entry criteria. Nine patients had a solitary nodule, three patients a lobar consolidation, and six patients had diffuse disease. For each patient, both breath-hold T2-weighted fast spin-echo, and breath-hold T1-weighted gradient-echo images, before and after injection of gadolinium, were available. Nine patients with pulmonary consolidation or diffuse disease had also heavily T2-weighted MR imaging (Haste or TSE 240; Siemens, Erlangen, Germany). MR imaging showed pulmonary abnormalities in 17 of 18 patients. Unenhanced T1-weighted and T2-weighted images depicted tumor in 16 of 18 patients. Contrast-enhanced T1-weighted images showed tumor in 17 of 18 patients. In no case did MR imaging depict abnormalities corresponding to the ground-glass opacities seen on CT scans. In three patients with mucinous bronchioloalveolar carcinoma, heavily T2-weighted images showed lesions isointense with respect to static fluid of the human body. In conclusion, the ability of MR imaging in detecting small nodules and ground-glass opacities is limited. However, heavily T2-weighted sequences are able to show the presence of mucin. This is useful information because mucinous bronchioloalveolar carcinoma carries a poor prognosis.