대한흉부영상의학회 Korean Society of Thoracic Radiology

Discussion

Diagnosis With Brief Discussion

Diagnosis

Intrapulmonary Lymph Node in NSIP (nonspecific interstitial pneumonia)

Radiologic Findings

HRCT scans show areas of ground-glass attenuation and irregular linear opacities with bronchial dilatation in the subpleural regions of both lower lung zones.
A 9-mm-sized, subpleural nodule is also seen in right lower lobe.

VATS (video-assisted thoracoscopic surgery) biopsy of the subpleural nodule and the right basal lung revealed anthracotic intrapulmonary lymph node and diffuse dense interstitial fibrosis (nonspecific interstitial pneumonia pattern with focal "DIP"-like reaction).

Brief Review

Articles about Intrapulmonary lymph nodes (IPLN)

According to Kradin et al,
the median age was 56 years, and 80 percent (eight) of the patients were men.
All patients are or were cigarette smokers.
Sixty percent (six) had a history of exposure to either asbestos, nonfibrous silicates, or both.
Forty percent (four) had an unexplained pulmonary nodule or nodules on the chest roentgenogram, which prompted further diagnostic studies, including thoracotomy, to rule out a malignant neoplasm.
Radiographically, in our cases and in the literature, almost all cases of intrapulmonary lymph nodes are
subpleural, inferior to the level of the carina, and less than 2.0 cm in diameter.
Thirty-five percent are multiple.
Pathologically, in our cases, all intrapulmonary lymph nodes were markedly anthracotic,
and 60 percent were additionally silicotic.
Although their histogenesis is uncertain, intrapulmonary lymph nodes are probably hyperplastic lymphoid nodules related to inhalation of irritant dusts and attendant distortion of local lymphatic vessels.

According to Yokomise et al,
IPLNs were located in the lower lobe in 72%.
The characteristic CT findings of IPLNs were a clear border and location close to the pleura.
We found that IPLNs located underneath the pleura are important to consider in the differential diagnosis of lung cancer.
The CT scan findings of IPLNs were not necessarily specific and sometimes resembled those of lung cancer. Because of their location, video-assisted thoracic surgery is useful in making a definite diagnosis.



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Articles about NSIP (Nonspecific interstitial pneumonia)

According to Park et al and Kim et al, nonspecific interstitial pneumonia with fibrosis is most commonly revealed as
patchy subpleural areas of ground-glass opacity mixed with irregular linear opacity or bronchial dilatation on HRCT.
These areas represent interstitial thickening caused by varying degrees of interstitial inflammation, fibrosis, or both.

According to Hartman et al, there are a wide variety of CT findings in cases of NSIP.
Eleven (22%) of the 50 patients had CT findings that were compatible with previous descriptions of NSIP.
Sixteen (32%) patients had CT findings that were more compatible with usual interstitial pneumonia.
The other 23 (46%) patients had findings that were nondiagnostic or most compatible with the diagnosis of another chronic infiltrative lung disease.

References

Kradin RL, Spirn PW, Mark EJ. Intrapulmonary lymph nodes. Clinical, radiologic, and pathologic features. Chest 1985 May;87(5):662-7

Yokomise H, Mizuno H, Ike O, Wada H, Hitomi S, Itoh H. Importance of intrapulmonary lymph nodes in the differential diagnosis of small pulmonary nodular shadows. Chest 1998 Mar;113(3):703-6

Park JS, Lee KS, Kim JS, et al. Nonspecific interstitial pneumonia with fibrosis: radiographic and CT findings in seven patients. Radiology 1995 Jun;195(3):645-8

Kim TS, Lee KS, Chung MP, et al. Nonspecific interstitial pneumonia with fibrosis: high-resolution CT and pathologic findings. AJR Am J Roentgenol 1998 Dec;171(6):1645-50

Hartman TE, Swensen SJ, Hansell DM, et al. Nonspecific interstitial pneumonia: variable appearance at high-resolution chest CT. Radiology 2000 Dec;217(3):701-5

Keywords

Lung, Lymphproliferative disorder, NSIP,