Diagnostic Accuracy of Triphasic CT Scan in Detection of Hepatocellular Carcinoma Versus Metastasis Keeping Histopathology as Gold Standard

Zainab Zahur; Uzma Mumtaz; Saba Akram; Mariam Malik; Amna Khalid

Authors

Zainab Zahur Consultant Radiologist, Atomic Energy Cancer Hospital, NORI, Islamabad
Uzma Mumtaz Assistant Professor of Radiology, Al-Nafees Medical College, Islamabad
Saba Akram Associate Professor of Radiology in Avicenna Medial College, Lahore
Mariam Malik Consultant Radiologist, Atomic Energy Cancer Hospital, INMOL, Islamabad
Amna Khalid Assistant Professor of Radiology in Fauji Foundation Medical College, Islamabad

Keywords:

Hepatocellular carcinoma, liver, biopsy, cirrhosis, patients, hemangiomas

Abstract

Background: The most prevalent primary tumor of liver is hepatocellular carcinoma (HCC) after metastasis, and it is also the 6th most frequent cancer in the world. Since long triphasic CT scan abdomen and serum alphafeto protein levels remains the standard of investigations for confirming HCC. Here we share our experience of appearance of HCC on dynamic liver CT scan, that not all HCC lesions shows typical pattern of enhancement in arterial phase or show washout in venous phase. The pattern of enhancement also differs for different types of HCC. In such cases histopathology gives us the correct answer as it is the gold standard.

Objective: To check the diagnostic accuracy of triphasic CT scan in detection of HCC comparing it with metastatic lesions while keeping biopsy as a gold standard.

Methods: It is a prospective cross-sectional study that was conducted at Radiology department of NORI cancer hospital from 1st Jan 2022 to 31st Dec 2022. Sample size was 50, and the patients coming for CT scan without known primary malignancy were carefully selected. Patient’s with hepatic lesions having equivocal pattern of enhancement (differential HCC Vs Metastasis), without any cirrhosis or altered AFP were included in the study. Of these, 39 underwent liver biopsy and were further divided into two groups (HCC Vs Non HCC/ Mets) depending on histopathology report. Patients with typical HCC lesions on Triphasic CT scan, cirrhotic liver morphology, raised AFP levels and benign lesions (e.g. hemangiomas) were excluded from our study.

Results: Our results of the study shows that 64.1 % had the histopathological diagnosis of metastatic disease and 35.9 % had typical HCC. The diagnosis of typical HCC was also confirmed by immunohistochemical marker of Hep-Par. Median age of patients was 40-60 years and the ratio of male: female was approx. 7:3.

Conclusion: There is a high frequency of false negative diagnosis for HCC on triphasic CT in patients with equivocal enhancement pattern and normal alpha feto protein level. This is particularly so in patients without cirrhosis. In such equivocal cases we must rely on biopsy and histopathology which is the gold standard in most of the cases.