Diagnosis of the case presented in the previous edition

RADIOLOGICAL DIAGNOSIS

Diagnosis of the case presented in the previous edition

Dany Jasinowodolinski; Ana Paula Klautau Leite; Nestor L. Müller

Fleury Center for Diagnostic Medicine, São Paulo (SP) Brazil; Universidade Federal de São Paulo (UNIFESP, Federal University of São Paulo), São Paulo (SP) Brazil; University of British Columbia, Vancouver, British Columbia, Canada.

Carcinoma Bronquioloalveolar

Comments

Bronchiolo-alveolar carcinoma (BAC) is a type of adenocarcinoma that occurs in the terminal bronchiolo-alveolar regions of the pulmonary parenchyma and is characterized by distinct tall epithelial cells, columnar to cuboid in shape and covering the alveolar septa, which project themselves in the alveolar spaces in numerous branched papillary formations, without signs of stromal, pleural or vascular invasion. Tumor cells frequently contain abundant mucinous secretions. Although the degree of anaplasia is quite variable, most tumors are differentiated and tend to preserve the original architecture of the septal wall. It is possible to classify cases of BAC as one of two variants: mucinous and nonmucinous.

Curiously, from the histological point of view, the alterations are similar to a disease known as Jaagsiekte, which affects sheep in South Africa and is caused by a betaretrovirus. However, no such causal relationship has been established in humans.

More than half of all patients with BAC are asymptomatic, and this form of neoplasia presents only a weak correlation with smoking. The most frequent symptoms are cough producing colorless sputum, episodes of dyspnea, weight loss, hemoptysis, and fever. Bronchorrhea is uncommon and, when present, is a late manifestation.

In terms of imaging, BAC has several presentations, manifesting as a solitary nodule, consolidations, areas of ground-glass opacity, or diffuse nodules. The patterns described above can also be accompanied by areas of pseudobullae with low attenuation and ectasia of the bronchi. These alterations can be focal or diffuse.

The characteristic finding of this case is the presence of areas called pseudocavitations or pseudobullous transparencies in the nodules. These areas probably represent air bronchograms and air bronchiolograms, which correspond to the pervious airways surrounded by the tumor. Although this characteristic is seen within the nodules, it can also be observed in the areas of ground-glass opacity. When this condition is present, a diagnosis of BAC should be considered in the differential diagnosis.

Referências

1. Robbins SL, Kumar V, Collins T. Patologia estrutural e funcional. In: Robbins SL. O pulmão. 6a ed. Rio de Janeiro:Guanabara Koogan; 2000. p. 671-3.

2. Naidich DP, Müller NL, Richard WW. Doenças caracterizadas por opacidades nodulares ou reticulonodulares. In: Webb WR, Müller NL, Naidich DP. TC de alta resolução do pulmão. 3a ed. Rio de Janeiro: Guanabara Koogan; 2002 p.254-7.

3. Rosado-de-Christenson ML, Templeton PA, Moran CA. Bronchogenic carcinoma: radiologic-pathologic correlation. Radiographics. 1994;14(2):429-46; quiz 447-8. Review.

4. Lee KS, Kim Y, Han J, Ko EJ, Park CK, Primack SL. Bronchioloalveolar carcinoma: clinical, histopathologic, and radiologic findings. Radiographics. 1997;17(6):1345-57. Review.

5. Zwirewich CV, Vedal S, Miller RR, Muller NL. Solitary pulmonary nodule: high-resolution CT and radiologic-pathologic correlation. Radiology. 1991;179(2):469-76.

Readers correctly diagnosing the case presented in the November/December 2006 issue:

Artur de Souto Goulart - Hospital São José - Criciuma - SC

Camilo Fernandes - Universidade Federal de Santa Catarina - UFSC - Florianópolis - SC

Elaine Maria Fonseca - Universidade Federal da Bahia - UFBA - Salvador - BA

João Adriano de Barros - Universidade Federal do Paraná - UFPR - Curitiba - PR

José Geraldo Felix de Seixas Maciel - Santa Casa de Misericordia de Belo Horizonte - Belo Horizonte - MG

Lilian Pinto de Azevedo Oliveira - Samer Hospital - Resende - RJ

Lúcia Helena Messias Sales - Universidade Federal do Pará - UFPA - Belém - PA

Luis Suárez Halty - Fundação Universidade Federal do Rio Grande - FUFRG - Rio Grande - RS

Mauricio Mello Roux Leite - Hospital Nossa Senhora da Conceição - Porto Alegre - RS

Robertina Pinheiro Roberto Barros - Faculdade de Medicina de Juazeiro do Norte - Juazeiro do Norte - CE

Suely Maria de Miranda Araújo - Hospital das Clínicas Gaspar Vianna - Belém - PA

Publication Dates

• Publication in this collection
  01 June 2007
• Date of issue
  Feb 2007