CT patterns of organizing pneumonia in patients treated with VEGF/mTOR inhibitors for metastatic renal cell cancer: an observational study.
BACKGROUND
Targeted therapies are the standard treatment in patients with metastatic renal cell carcinoma (mRCC) and are known to cause adverse pulmonary events. Organizing pneumonia (OP) with its various manifestations in computed tomography (CT) has therefore lately received more attention.


OBJECTIVE
To describe the spectrum of CT patterns of OP in patients with mRCC receiving targeted therapies.


METHODS
Seventeen patients with known therapy-related OP were analyzed retrospectively by two blinded radiologists in consensus. Images were scored according to OP patterns that have previously been described. Additionally, the distribution and the predominant imaging pattern in each patient were determined.


RESULTS
In our cohort, ground glass opacity was the most common imaging pattern (17/17, 100%) in patients with OP followed by a reticular pattern (12/17, 71%), consolidations (10/17, 59%), nodules (7/17, 41%), crazy paving (5/17, 29%), bronchi(ol)ectasis (4/17, 24%), focal mass (3/17, 18%), and reversed halo (1/17, 6%). The most common imaging pattern was changing multifocal consolidations (8/17, 47%). A bronchocentric and a nodular pattern were found in four patients (24%) each, a progressive fibrotic pattern in none patient, and reversed halo/atoll pattern in one (6%) case.


CONCLUSIONS
OP is the major differential diagnosis to be considered in patients with targeted therapies and pulmonary changes. Knowledge of the variety of imaging findings can facilitate diagnosis.
Department of Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany.
Sabine
S
Dettmer
Department of Haematology, Haemostasis, Oncology and Stem Cell Transplantation, Hannover Medical School, Hannover, Germany.
Viktor
V
Grünwald
Department of Respiratory Medicine, Hannover Medical School, Hannover, Germany.
Thomas
T
Fuehner
Department of Haematology, Haemostasis, Oncology and Stem Cell Transplantation, Hannover Medical School, Hannover, Germany.
Arnold
A
Ganser
Department of Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany.
Frank
F
Wacker
Department of Haematology, Haemostasis, Oncology and Stem Cell Transplantation, Hannover Medical School, Hannover, Germany.
Philipp
P
Ivanyi
Department of Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany.
Thomas
T
Rodt
Organizing pneumonia; computed tomography (CT); interstitial lung disease; renal cell cancer; targeted therapy