Y. Kim et al., Coexisting bronchogenic carcinoma and pulmonary tuberculosis in the same lobe: Radiologic findings and clinical significance, KOREAN J RA, 2(3), 2001, pp. 138-144
Objective: Bronchogenic carcinoma can mimic or be masked by pulmonary tuber
culosis (TB), and the aim of this study was to describe the radiologic find
ings and clinical significance of bronchogenic carcinoma and pulmonary TB w
hich coexist in the same lobe.
Materials and Methods: The findings of 51 patients (48 males and three fema
les, aged 48-79 years) in whom pulmonary TB and bronchogenic carcinoma coex
isted in the same lobe were analyzed. The morphologic characteristics of a
tumor, such as its diameter and margin, the presence of calcification or ca
vitation, and mediastinal lymphadenopathy, as seen at CT, were retrospectiv
ely assessed, and the clinical stage of the lung cancer was also determined
. Using the serial chest radiographs available for 21 patients, the possibl
e causes of delay in the diagnosis of lung cancer were analyzed.
Results: Lung cancers with coexisting pulmonary TB were located predominant
ly in the upper lobes (82.4%). The mean diameter of the mass was 5.3 cm, an
d most tumors (n=42, 82.4%) had a lobulated border. Calcification within th
e tumor was seen in 20 patients (39.2%), and cavitation in five (9.8%). For
ty-two (82.4%) had mediastinal lymphadenopathy, and more than half the tumo
rs (60.8%) were at an advanced stage [IIIB (n=11) or IV (n=20)]. The averag
e delay in diagnosing lung cancer was 11.7 (range, 1-24) months, and the ca
uses of this were failure to observe new nodules masked by coexisting stabl
e TB lesions (n=8), misinterpretation of new lesions as aggravation of TB (
n=5), misinterpretation of lung cancer as tuberculoma at initial radiograph
y (n=4), masking of the nodule by an active TB lesion (n=3), and subtleness
of the lesion (n=1).
Conclusion: Most cancers concurrent with TB are large, lobulated masses wit
h mediastinal lymphadenopathy, indicating that the morphologic characterist
ics of lung cancer with coexisting pulmonary TB are similar to those of lun
g cancer without TB. The diagnosis of lung cancer is delayed mainly because
of masking by a tuberculous lesion, and this suggests that in patients in
whom a predominant or growing nodule is present and who show little improve
ment of symptoms despite antituberculous or other medical therapy, coexisti
ng cancer should be suspected.