Re-appearance of power Doppler signals in the tumor nodules of hepatocellular carcinoma after transarterial embolization reflects residual viable tumor cells: histological confirmation.
OBJECTIVE
A recent advance in ultrasonography is the use of power Doppler for detecting low-velocity angle-independent blood flow at the microvascular level. The present study was prospectively performed to elucidate the relationship between the power Doppler signals of hepatocellular carcinoma after transarterial embolization and histological confirmation of viable tumor cells.


METHODS
The observance of hepatocellular carcinoma-related Doppler signals in 48 patients with 67 nodules was examined after transarterial embolization, and its correlation with the presence of viable tumor cells using ultrasound-guided biopsy specimens was analyzed.


RESULTS
Power Doppler signals disappeared in 54 out of 67 nodules (80%) one day after transarterial embolization, but the signals re-appeared in 55-53% of the specimens at 4-7 days and 10-14 days after treatment. Viable tumor cells were histologically proven in 27 of 34 nodules (79%) presenting power Doppler signals, while only 5 of the 22 nodules (23%) negative for Doppler signals confined viable tumor cells (P<0.001). Univariate and multivariate analysis showed that the detection of power Doppler signals after transarterial embolization was related to the size of the tumor and the presence of viable tumor cells (both, P<0.001).


CONCLUSIONS
These results indicate that the presence of power Doppler signals may reflect the presence of viable tumor cells after transarterial embolization, leading to the need for further treatment of hepatocellular carcinoma nodules.
Sato
Shin'pei
S
Department of Gastroenterology, University of Tokyo, Japan.
Shiratori
Yasushi
Y
Imamura
Masatoshi
M
Obi
Shun'taro
S
Shiina
Shuichiro
S
Akahane
Masaaki
M
Ohtomo
Kuni
K
Omata
Masao
M
D006528:Carcinoma, Hepatocellular / Q000098:blood supply / Q000000981:diagnostic imaging* / Q000473:pathology / Q000628:therapy; D004621:Embolization, Therapeutic; D006801:Humans; D008113:Liver Neoplasms / Q000098:blood supply / Q000000981:diagnostic imaging* / Q000473:pathology / Q000628:therapy; D015999:Multivariate Analysis; D018365:Neoplasm, Residual / Q000000981:diagnostic imaging* / Q000473:pathology; D011446:Prospective Studies; D018608:Ultrasonography, Doppler