Case Author(s): Akash Sharma, M.D., Dennis M. Hsueh, M.D. and Tom R. Miller, M.D., Ph.D. , 08/28/04 . Rating: #D3, #Q4

Diagnosis: Brochiolitis obliterans with organizing pneumonia (BOOP)

Brief history:

Seventy-three year old female presents with worsening dyspnea and abnormal liver function tests. Prior right mastectomy for breast cancer.



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View fourth image(mc). Initial work-up U/S, followed by MRI

Full history/Diagnosis is available below

Diagnosis: Brochiolitis obliterans with organizing pneumonia (BOOP)

Full history:

Seventy-three-year-old woman with a history of right breast cancer approximately six years ago treated with mastectomy and radiation therapy. The patient presents with worsening dyspnea with mediastinal adenopathy and a focal splenic lesion identified on MRI examination. This is a re-staging examination.


F-18 FDG i.v.


1. PET-CT: Patchy moderately intense uptake in both lungs favoring an inflammatory or infectious process such as bronchiolitis obliterans with organizing pneumonia as suggested on CT examination, although lymphangitic tumor spread is not excluded on the basis of PET imaging. There is no abnormal splenic uptake and no evidence for other loco-regional or distant evidence of metastatic disease.

2. Chest CT (prior to PET: Diffuse patchy, symmetric, ground-glass opacities with upper lobe predominance. A few thickened septal lines are noted, and there are a few small foci of consolidation. These findings are not the expected appearance of lymphangitic spread of tumor. If the patient has been on chemotherapy, these findings can be seen in the setting of acute on chronic hypersensitivity reaction with areas of bronchiolitis obliterans and bronchiolitis obliterans organizing pneumonia. Given the somewhat peripheral distribution in the lung apices, eosinophilic pneumonia may also have a similar appearance.

3. Abdomen ultrasound: Solid spherical mass within the spleen, statistically most likely a benign hemangioma. However, in a person with a personal history of malignancy, evaluation with additional dedicated cross-sectional imaging should be performed.

4. Abdomen MRI: A 6.6 x 5.5 cm heterogeneous lesion demonstrating enhancement in the inferior aspect of the spleen. This most likely represents a benign lesion such as a hamartoma or atypical hemangioma. However, malignancy such as lymphoma and less likely metastatis cannot be excluded. PET imaging may be useful for further evaluation if clinically indicated.


The uptake pattern in the lungs in this patient is non-specific. While PET-CT is a good way to evaluate patient for recurrence of malignancy, other etiologies such as active infection/inflammation can decrease the sensitivity of this study for eliciting recurrent metastates. The CT findings in conjunction with the increased uptake seen on PET are helpful in providing alternate diagnoses. Biopsy of the affected area is still needed for definitive diagnosis.

References: 1. Preliminary Findings of a Prospective Study of FDG-PET in Patients with Possible Lung Cancer. Clin Positron Imaging. 2000 Jul;3(4):158.

N.B. The entity known as BOOP is now also referred to as Cryptogenic Organizing Pneumonia.

Radiol Clin North Am. 2001 Nov;39(6):1153-70. High-resolution CT of idiopathic interstitial pneumonias


Patient underwent a tranbronchial lung biopsy which revealed the diagnosis of :


Patient's dyspnea did not resolve even after high dose treatment with prednison. She expired two weeks later.

Differential Diagnosis List

Brochiolitis obliterans with organizing pneumonia vs. atypical pattern of lymphangitic spread of recurrent breast cancer.

ACR Codes and Keywords:

References and General Discussion of PET Tumor Imaging Studies (Anatomic field:Lung, Mediastinum, and Pleura, Category:Inflammation,Infection)

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Case number: pt115

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