Diagnosis: Bronchioloalveolar carcinoma, multicentric or diffuse pattern
Radiologic Findings |
Chest radiograph shows multiple poorly-defined nodular opacities in both lungs with predominant distribution in peripheral and lower lung zones. Chest CT scans show multiple nodules and consolidations with or without a halo of ground-glass attenuation in the both peripheral lungs. CT-angiogram sign is seen in the consolidations of both lower lobes. |
Brief Review |
Bronchioloalveolar carcinoma can be defined as a peripheral, well-differentiated neoplasm, with a tendency to spread locally in the peripheral air space, using the lung structure as stroma. Three types of this primary carcinoma of the lung have been recognized: a solitary nodule(43%), consolidation(30%), and multicentric or diffuse disease(27%). A characteristic finding of bronchioloalveolar carcinoma is presence of bubble-like lucencies and pseudocavitation, which corresponds to patent small bronchi or air-containing cystic spaces in papillary tumors. Mucin is of lower radiographic density than tumor, so it creates the areas of lower attenuation on mediastinal windows. The low attenuation allows vessels to be clearly seen, particularly after administration of IV contrast material. This finding, described as the CT angiogram sign, is suggestive but not specific for bronchioloalveolar carcinoma. Multicentric or diffuse bronchioloalveolar carcinoma could be classified into three patterns: predominantly ground-glass, consolidative, and multinodular. Most patients with diffuse bronchioloalveolar carcinoma had a mixture of these findings. Differential diagnosis of diffuse bronchioloalveolar carcinoma includes bronchogenic dissemination of tuberculosis, pneumonia in immunosuppressed patients, fungal infection, and hematogenous metastasis. |
References |
1. M Akira, S Atagi, M Kawahara, K Iuchi, and T Johkoh. High-resolution CT findings of diffuse bronchioloalveolar
carcinoma in 38 patients. AJR 1999;173:1623-1629 |
A letter from Dr. Kyung Soo Lee, the Editor of Website.
Dear Dr. Kim:
This case is also a typical case needing multiple differential diagnoses.
The patient complained of cough and sputum for two weeks.
Absence of fever or chill suggests the case is not from a patient with pulmonary infection.
Findings what I am now seeing are masses and nodules in both lungs with surrounding halo of ground-glass opacity.
In right upper lobe, some features of branching linear structure are seen.
The differential diagnosis of nodules or masses with halo sign includes various diseases.
Because we can rid of infectious conditions, I put tumorous condition first. Multiplicity favors metastasis
(such as choriocarcinoma, renal cell carcinoma, and angiosarcoma).
Among these, choriocarcinoma may present as hemorrhagic metastasis with vascular component
(tumor thrombus and branching structure as in this particular case). Multiplicity precludes the diagnosis of
bronchioloalveolar carcinoma or lymphoma.
Other diagnoses include inflammatory disease such as PIE syndrome or angiitis and granulomatosis
(Wegener's granulomatosis, lymphomatoid granulomatosis).
Because PIE syndrome usually does not show such an extensive area of consolidation or mass,
Wegener's granulomatosis may be the second most probable diagnosis.
However, again in this case, clinical history is in shortage. Laboratory findings or previous medical history
may help in differential diagnosis.
In summary, my first diagnosis is hemorrhagic metastasis from choriocarcinoma
and the second one is Wegener's granulomatosis.
With best wishes.
Kyung Soo Lee, MD
Return to Images