A prospective comparison of growth patterns with radiomorphology in 232 lung metastases—basis for patient tailored resection planning?

Nomair Issa, Elias Arfanis, Thomas Hager, Clemens Aigner, Sarah Dietz-Terjung, Dirk Theegarten, Hilmar Kühl, Stefan Welter


Background: The histologic presence of aggressive local growth of pulmonary metastases is associated with an increased risk for local intrapulmonary recurrence after enucleation or wedge resection. Patient tailored resection planning is possible when morphologic pattern of aggressive growth could be identified based on preoperative CT scans.
Methods: Radiomorphology and microscopic growth characteristics from 232 pulmonary metastases from 87 patients were prospectively compared for the presence or absence of aggressive patterns of local intrapulmonary dissemination.
Results: Microscopic aggressive local growth was found: pleural involvement (18.5%), lymphatic invasion (6.9%), vascular invasion (7.3%), interstitial growth (38.4%), micro satellite nodules (24.5%), spread through air spaces (STAS) (13.4%), and a smooth, slightly blurred or irregular surface in 34.1%, 43.1% and 22.8%. The radiologic margin demarcation was smooth in 37.1%, blurred in 27.6% or irregular in 35.3% and spiculae were present in 26.3% of the lesions. The microscopic and radiologic description of the metastasis surface correlated well [correlation coefficient (CC) =0.75, P<0.001]. A smooth surface on CT scan corresponded with a smooth microscopic surface in 72/86 (83.7%) of the lesions. The radiomorphologic feature of an irregular or cloudy surface was highly associated with the presence of at least one aggressive pattern of local dissemination (P<0.001). The presence of spiculae on CT scan was well associated with the presence of aggressive local spread (P<0.001) and the microscopic features corresponding with spiculae were interstitial growth, STAS and L1.
Conclusions: Radiomorphologic characteristics of lung metastases correspond well with the microscopic appearance of the resected lesion. Therefore it seems possible to adjust safety margins based on the radiologic appearance of the metastasis.