Sarcoid-like reaction-computed tomography features in 12 patients.

PURPOSE: The aim of the study was to analyze the computed tomography (CT) findings of sarcoid-like reaction caused by underlying malignancy or immune modulation. METHODS: Twelve patients with pathologically proven sarcoidosis from underlying causes (malignancies, hepatitis C infection, and immune-modulatory treatment) in 2001 to 2011 were identified. All patients had chest CT scans, which were reviewed by 3 experienced thoracic radiologists. Medical records were also reviewed. Follow-up imaging, available in 11 patients, was assessed for response. RESULTS: All patients were white, 8 women and 4 men, with ages ranging from 26 to 72 years. Seven had underlying malignancy, 2 had inflammatory bowel disease, and 3 had liver disease caused by chronic hepatitis C viral infection. On CT, 92% (11/12) of patients had lymphadenopathy, 75% (9/12) had pulmonary nodules less than 5 mm, and 50% (6/12) had ground-glass opacity (GGO). In 42% (5/12) of patients, the dominant finding was discrete nodules (1-5 mm). In 33% (4/12) of patients, the dominant finding was ultrafine nodules with confluence, mimicking GGO. The most common distribution of lung nodules was perilymphatic, found in 78% (7 of the 9 patients with lung nodules). Follow-up was available in 10 patients, limited follow-up in 1, and no follow-up in 1. Six of the 11 patients who had follow-up had complete resolution of CT findings, 3 had partial resolution, and 2 had no resolution. CONCLUSIONS: Imaging features of patients with sarcoid-like reaction include lymphadenopathy, small nodules, and ultrafine nodules with confluence, mimicking GGO. Ultrafine nodules with confluence mimicking GGO were unexpectedly common in this series.

Tumors and tumorlike conditions of the large airways.

OBJECTIVE: Large-airway tumors and tumorlike conditions are uncommon, but a systematic approach aids in narrowing the differential diagnosis. In this article, we describe an approach to dealing with large-airway lesions and discuss their imaging characteristics and clinical presentations. CONCLUSION: We have found it useful to separate these entities into groups on the basis of the distribution pattern (focal vs diffuse) and location (trachea vs bronchi).

Tumorlike conditions of the pleura.

Tumorlike conditions of the pleura are rare, but diagnosis is facilitated by recognizing certain imaging patterns and interpreting them in the clinical context. A tumorlike condition of the pleura is any nonneoplastic lesion of the pleura itself, or within the pleural space, that resembles a tumor. An approach to diagnosis of the tumorlike conditions of the pleura is provided, and these conditions are grouped into focal or diffuse conditions, with an emphasis on specific imaging features. Focal tumorlike conditions of the pleura include pleural plaque, thoracic splenosis, thoracic endometriosis causing catamenial pneumothorax, and pseudotumor caused by pleural effusion. Thoracic splenosis should be considered in a patient who has a healed left lower rib fracture, an absent spleen, and left lower pleural nodules. Thoracic endometriosis with catamenial pneumothorax should be considered in a woman of childbearing age who presents with right scapular pain and recurrent pneumothorax occurring at or around the onset of menses. Extrapleural hematoma is a nonpleural mimic of pleural tumor and shares some imaging features with focal tumorlike conditions of the pleura, despite residing in the extrapleural space. Diffuse tumorlike conditions of the pleura include diffuse pleural thickening and rare conditions such as Erdheim-Chester disease and diffuse pulmonary lymphangiomatosis. Erdheim-Chester disease should be considered when diffuse pleural thickening occurs with a perirenal soft-tissue halo or distal femoral sclerosis. Diffuse pulmonary lymphangiomatosis should be considered when findings include diffuse pleural thickening, interlobular septal and peribronchovascular interstitial thickening, and mediastinal fat infiltration limited to the thorax and when these findings persist despite diuretic therapy.

Chronic obstructive pulmonary disease: radiology-pathology correlation.

Chronic obstructive pulmonary disease is defined as a preventable and treatable disease state characterized by airflow limitation that is not fully reversible. This review will discuss the relevant anatomy of the secondary pulmonary lobule, the subtypes of emphysema, and their imaging appearances and corresponding pathologic findings.

Relationship between non-small cell lung cancer fluorodeoxyglucose uptake at positron emission tomography and surgical stage with relevance to patient prognosis.

PURPOSE: Because the tumor stage is the most significant prognostic factor for non-small cell lung cancer (NSCLC) and given that NSCLC [(18)F]fluorodeoxyglucose ((18)F-FDG) uptake appears to have prognostic significance, we examined the relationship between NSCLC (18)F-FDG uptake and surgical stage. EXPERIMENTAL DESIGN: One hundred seventy-eight patients with a proven diagnosis of NSCLC were enrolled, then imaged with (18)F-FDG positron emission tomography and their disease thoroughly staged. Primary tumor size at computed tomography and (18)F-FDG uptake were compared to overall tumor stage and to T, N, and M stage descriptors. Tumor uptake was quantitated by maximum pixel-standardized uptake value (maxSUV) and then partial volume corrected for lesion size using recovery coefficients. RESULTS: A significant difference in tumor size was associated with tumors of different TNM stage, T status, N status, or M status. Similarly, the primary tumor maxSUV was significantly associated with TNM stage, T status, and M status. However, we observed no significant difference in the partial-volume-corrected tumor maxSUV for different stages; different T, N, or M descriptors; tumors without evidence of spread (N(0)M(0)) versus tumors with nodal spread (N(1,2,3)M(0)); or tumors without spread (N(0)M(0)) versus all others. CONCLUSIONS: We found an association between tumor stage and (18)F-FDG maxSUV, but this relationship disappeared after correction of tumor uptake for lesion size. Therefore, if partial-volume-corrected (18)F-FDG uptake is prognostic of NSCLC outcome, it is not on the basis of a relationship with tumor stage but through a different mechanism.

Diffuse pulmonary ossification.

Diffuse pulmonary ossification (DPO) is an uncommon condition that is characterized by metaplastic bone formation in the lung parenchyma. It is usually not diagnosed clinically and may be apparent radiographically only when extensive. However, it is occasionally encountered at autopsy or on pathologic evaluation of surgical specimens. This article will review the clinical, histologic, and radiographic manifestations of DPO, focusing primarily on the chest radiograph and CT findings, both of which may be underappreciated, for even experienced radiologists may confuse DPO with other entities such as metastatic calcification as seen in chronic renal failure or chronic granulomatous disease.