Small peripheral lung carcinomas with five-year post-surgical follow-up: assessment by semi-automated volumetric measurement of tumour size, CT value and growth rate on TSCT.

Abstract

To retrospectively assess the utility of semi-automated measurements by stratification of CT values of tumour size, CT value and doubling time (DT) using thin-section computed tomography (CT) images. The post-surgical outcomes of favourable and problematic tumours (more advanced p stage than IA, post-surgical recurrence or mortality from lung cancer) were compared using the measured values. The computed DTs were compared with manually measured values. The study subjects comprised 85 patients (aged 33-80 years, 48 women, 37 men), followed-up for more than 5 years postoperatively, with 89 lung lesions, including 17 atypical adenomatous hyperplasias and 72 lung cancers. DTs were determined in 45 lesions. For problematic lesions, whole tumour diameter and density were >18 mm and >-400 HU, respectively. The respective values for the tumour core (with CT values of -350 to 150 HU) were >15 mm and >-70 HU. Analysis of tumour core DTs showed interval tumour progression even if little progress was seen by standard tumour volume DT (TVDT). Software-based volumetric measurements by stratification of CT values provide valuable information on tumour core and help estimate tumour aggressiveness and interval tumour progression better than standard manually measured 2D-VDTs.