Imaging description

Metastatic pulmonary calcification on CT is characterized by patchy or confluent parenchymal opacities most commonly in the upper lungs. These are typically ground-glass, although there may be frank consolidation (Figures 21.1 and 21.2). The focal opacities often appear to be centrilobular (Figure 20.1) although histologically the calcium is located within the interlobular septa [1–3]. Punctate parenchymal calcification is a common feature (60%). There may also be associated calcification in the chest wall vessels. It is postulated that the lung apices are most frequently involved due to the relatively greater ventilation to perfusion and the relative tissue alkalinity [1–3].

Importance

Although metastatic pulmonary calcification is uncommon, the imaging findings can strongly suggest the diagnosis in the appropriate clinical context. If the diagnosis is uncertain based on CT, a nuclear medicine bone scan may confirm the diagnosis [4].