Role of multislice computed tomography 3D volumetric analysis in the assessment of the therapeutic response of hepatocellular carcinoma after transarterial chemoembolization

Abstract

Background Volumetric analysis is a novel radiological technique used in the measurement of target lesions in three dimensions in order to estimate the lesion’s volume. Recently, it has been used for evaluation of the remaining liver volume after partial hepatectomy and also for evaluation of the response of tumours to treatment. It has been proven to be more accurate than the standard one or two-dimensional measurements, and it is especially useful for the evaluation of complex tumours after radiological interventional methods when the use of standard methods is limited. In the current study, our aim was to evaluate the value of the three-dimensional (3D) volumetric method “Response Evaluation Criteria in Solid Tumours (vRECIST)” and to compare it with the non–three-dimensional methods (RECIST) and modified RECIST (mRECIST) in the assessment of the therapeutic response of hepatocellular carcinoma (HCC) after transarterial chemoembolization (TACE). Results A retrospective study was conducted on 50 patients with confirmed radiological or pathological diagnosis of hepatocellular carcinoma (HCC) who underwent TACE as the only interventional procedure and follwed up by triphasic CT 1 and 4 months after treatment. The study revealed a significant difference between mRECIST and vRECIST in the assessment of the therapeutic response of HCC after TACE, a weak agreement was found between both methods in the detection of complete response (CR), partial response (PR), stable disease (SD) or progressive disease (PD). Also, there was no significant agreement between mRECIST and vRECIST regarding the assessment by classifying the patients into responders or nonresponders. Conclusion Volumetric analysis is an effective method for measuring the HCC lesions and evaluating its response to locoregional treatment with a significant difference between vRECIST and mRECIST in the assessment of therapeutic response, which in turn help the interventional radiologist to decide the future treatments and change the therapeutic plans. Based on these results, we recommend vRECIST to be an essential part of the assessment of therapeutic response after locoregional therapy.

Nuclear Imaging and Therapy

“…Long-acting release (LAR) pasireotide tended to have increased tumour control rate after 6 months and longer PFS compared to octreotide-LAR. Combination therapy of pasireotide-LAR and everolimus showed no additional benefits of the addition of pasireotide (73).…”

“…SSTR antagonists (e.g. 177 Lu-OPS201) potentially have higher tumour uptake and decreased uptake in healthy organs compared to 177 Lu-DOTATATE and shows efficacy in a phase 1 trial of metastatic, well-differentiated NET (72,73). The use of α…”

“… 177 Lu-DOTATATE is the most widely employed radiopeptide for PRRT mainly due to its lower nephrotoxicity compared to 90 Y-DOTATOC.  Although PRRT is limited to high-SSTR2 expressing tumours, the underlying approach of PRRT emitters, like 213 Bi, may lead to increased tumour DNA damage, but is challenged by problems of renal and haematological toxicity (73). Additionally, other pharmaceutical agents (olaparib) could sensitize NET cells to PRRT according to in vitro models (74).…”

“…Another field of development are immunotherapy agents (e.g. pembrolizumab) and multi-receptor chimeras that target both somatostatin and dopamine, but need improvements before clinical application can be initiated (73).…”

“…A prospective multicentre trial is underway looking at DOR while combining personal pre-and posttreatment dosimetry with a target TAD of more than 150 Gy (NCT04736121). To assess tumour response to therapy, the modified RECIST criteria are used in my studies (73). It is a one-dimensional measurement of arterial enhancement of the lesion.…”