Is visual radiological evaluation of liver tumour burden in patients with neuroendocrine tumours reproducible?

Abstract

BackgroundVisual semi-quantitative assessment of liver tumour burden for neuroendocrine tumour liver metastases is often used in patient management and outcome. However, published data on the reproducibility of these evaluations are lacking.ObjectiveThe aim of this study was to evaluate the interobserver and intraobserver agreement of a visual semi-quantitative assessment of liver tumour burden using CT scan.MethodsFifty consecutive patients (24 men and 26 women, mean aged 54 years) were retrospectively reviewed by four readers (two senior radiologists, one junior radiologist and one gastroenterologist) who assessed the liver tumour burden based on a visual semi-quantitative method with four classes (0–10, 11–25, 26–50 and ≥50%). Interobserver and intraobserver agreement were assessed by weighted kappa coefficient and percentage of agreement. The intraclass correlation was calculated.ResultsAgreement among the four observers for the evaluation of liver tumour burden was substantial, ranging from 0.62 to 0.73 (P < 0.0001). The intraclass coefficient was 0.977 (P < 0.0001). Intraobserver agreement was 0.78 and ICC was 0.97.ConclusionReproducibility of the visual semi-quantitative evaluation of liver tumour burden is good and is independent of the level of experience of the readers. We therefore suggest that clinical studies in patients with neuroendocrine liver metastases use this method to categorise liver tumour burden.

High Interobserver Agreement for the Standardized Reporting System SSTR-RADS 1.0 on Somatostatin Receptor PET/CT

“…This is in line with a report of Fendler et al describing an excellent agreement rate when evaluating the overall scan result of SSTR-PET/CTs in a binary fashion in less trained observers (κ = 0.80) (24). In neuroendocrine liver lesions, contrast-enhanced CT acquisitions revealed only a substantial concordance rate on a visual assessment among junior vs. senior abdominal radiologists when using a non-standardized approach (κ = 0.62) (31). Of note, SSTR-PET/CT enables for a non-invasive whole-body readout and thus, may be associated with a higher degree of complexity as it is not restricted to one single organ but allows for investigation of every putative site of disease (32).…”

Proposal of early CT morphological criteria for response of liver metastases to systemic treatments in gastroenteropancreatic neuroendocrine tumors: Alternatives to RECIST

“…Nevertheless, CT-scan measurements are usually reproducible in GEP-NET imaging. 14,22,30 Also, patient inclusions were limited by the lack of extensive imaging databases in many expert institutions. To optimize the homogeneity of our series, many patients met exclusion criteria related to the delays between baseline CT-scan, treatment initiation and first evaluation CT-scan, underlining possible differences in routine management across institutions.…”

“…Interobserver variability could not be evaluated. Nevertheless, CT‐scan measurements are usually reproducible in GEP‐NET imaging 14,22,30 . Also, patient inclusions were limited by the lack of extensive imaging databases in many expert institutions.…”

“…Anonymized data were retrospectively collected in each center, including primary tumor origin, ECOG performance status, functioning syndrome, Ki‐67 index and tumor grade according to the 2019 WHO classification 20 . Percent of metastatic liver involvement was classified as 1%–10%, 11%–25%, 26%–50% or >50% 22 . The beginning and end dates of each treatment, and the reason for treatment discontinuation (progression, toxicity) were collected.…”

“…20 Percent of metastatic liver involvement was classified as 1%-10%, 11%-25%, 26%-50% or >50%. 22 The beginning and end dates of each treatment, and the reason for treatment discontinuation (progression, toxicity) were collected. We collected the date of treatment failure, defined in local expert tumor boards of each center, according to clinical, biological and morphological criteria per RECIST 1.1.…”