Complete regression of hepatocellular carcinoma under tamoxifen

Spontaneous regression of metastatic hepatocellular carcinoma following 3 weeks of lenvatinib

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related mortality and is associated with a poor prognosis. Rarely, there is spontaneous regression of the tumour. We present a case of a middle-aged male with presumed metastatic HCC who experienced enduring regression following 3 weeks of lenvatinib, which was discontinued due to side effects. While this could represent an unusually successful response to therapy, spontaneous tumour regression or an alternative diagnosis should be considered. We discuss possible mechanisms that might explain this unusual case and advocate for tissue confirmation in select cases, where there is diagnostic doubt or when the disease pattern does not clearly follow the recognised natural history. Therefore, if regression occurs-whether spontaneous or in response to treatment-it can be better understood and subsequent therapies recommended.

Chemoprevention of hepatocellular carcinoma: Use of tamoxifen in an animal model of hepatocarcinogenesis

Hepatocellular carcinoma (HCC) is common worldwide and growing in importance in the West. HCC often occurs against a background of liver disease, tends to present at an advanced stage, and has a poor prognosis, suggesting that it is an ideal target for chemoprevention. We sought to identify in an animal model chemopreventive agents for HCC that might be tested in human subjects. To this end, we induced liver tumors by injecting ethyl-nitrosourea in 6-week-old male B6C3F1 mice. Two chemopreventive agents were administered over a period of 60 weeks: tamoxifen (420 mg/kg feed) and a retinoid, 13-cis-retinoic acid (200 mg/kg feed). Animals were killed at 60 weeks and their livers examined for HCC and premalignant lesions. All liver lesions (altered foci, adenomata, HCC) occurred significantly less frequently in the tamoxifen-treated group than the group given only ethylnitrosourea (HCC developed in 2 of 47 (4%) vs 11 of 44 (25%); P < .001). On the other hand, retinoic acid appeared to increase the number of liver tumors, and in 2 animals angiosarcoma developed. Tamoxifen significantly decreased the incidence of chemical hepatocarcinogenesis in this model, suggesting an important role for estrogens in the pathogenesis of HCC and suggesting that it should be tested in human beings as a chemopreventive agent against HCC.

Two cases of spontaneous regression of multicentric hepatocellular carcinoma after intraperitoneal rupture: possible role of immune mechanisms

We report two cases of spontaneous regression of hepatocellular carcinoma. Firstly, a 64-year-old man with alcohol related cirrhosis developed multiple liver tumours with elevation of the alpha-fetoprotein level at 915 ng/ml. A spontaneous regression of all the tumoural masses but one and normalization of the alpha-fetoprotein level was observed after intraperitoneal spread of the malignancy. Resection of the remaining tumour 9 months later confirmed a hepatocellular carcinoma. Secondly, a 70-year-old woman with alcohol related cirrhosis developed multiple liver tumours with elevation of the alpha-fetoprotein level to 4000 ng/ml; a regression of all the tumoural masses but one and a decrease of the alpha-fetoprotein level to 400 ng/ml was observed after intraperitoneal spread of the malignancy and treatment with tamoxifen. We discuss a possible immune mechanism of tumoural regression with a review of similar cases described in the literature.