Incidence and therapeutic frequency of extrahepatic collateral arteries in transcatheter arterial chemoembolization of hepatocellular carcinoma: Experience from 182 patients with survival time more than 3 years

• The Angiography of RIPA be performed at the first TACE session.
• RIPA is the most common collateral artery initially confirmed at TACE sessions.
• EHCAs should be searched in the order: RIPA, RIMA, LIPA and other collaterals.
• RIPA, RICA and COA need multiple TACE sessions to be successfully treated.

PurposeTo retrospectively evaluate the incidence of each extrahepatic collateral artery (EHCA) supplying to hepatocellular carcinoma (HCC) in sessions of transcatheter arterial chemoembolization (TACE) and its therapeutic frequency.Materials and methodsBetween February 2002 and May 2008, 182 patients with HCC underwent TACE and survived more than 3 years. For TACE procedure, angiographic evaluation of all suspected EHCAs that could supply the tumor were performed. The incidence of EHCAs in TACE sessions and therapeutic frequency were analyzed. Correlations between the number of collaterals and the number of TACE sessions were investigated.Results162 patients showed 647 EHCAs supplying tumors in a total of 795 sessions of TACE. The initially confirmed EHCAs in TACE sessions were the right inferior phrenic artery (RIPA, n = 150), left inferior phrenic artery (LIPA, n = 8), right internal mammary artery (RIMA, n = 4), right adrenal artery (RAA, n = 2) and left gastric artery (LGA, n = 5), respectively. The incidences of EHCAs were 51.1%, 68.1%, 50.0%, 50.0%, 42.3%, 34.6%, 29.1%, 19.8%, 6.6%, 3.3% and 0.6% from 1 to 11 session of TACE, respectively. The RIPA was accounted for 62.5% of EHCAs and other EHCAs often occurred after the attenuation of RIPA. There were correlations between the number of TACE sessions and either the sum number of collaterals (r = −0.961; p < 0.001), the number of RIPA(r = −0.948; p < 0.001) or the number of LGA(r = −0.670; p = 0.024). The mean therapeutic frequencies of TACE were 2.6, 1.5, 1.6, 1.3, 1.5, 1.2, 3.3, 1.1, 1.0 and 7.0 times for the RIPA, LIPA, RIMA, left internal mammary artery (LIMA), omental artery (OMA), LGA, right intercostal artery (RICA), RAA, right renal capsular artery (RRCA) and colic artery (COA), respectively.ConclusionsThe RIPA angiography should be routinely performed in TACE procedure. EHCAs should be searched during the sessions of TACE in the following order: RIPA, RIMA, LIPA and other collaterals of lower incidence.