Complete regression following sorafenib in unresectable, locally advanced hepatocellular carcinoma

Role of Silymarin in Cancer Treatment: Facts, Hypotheses, and Questions

The flavonoid silymarin extracted from the seeds of Sylibum marianum is a mixture of 6 flavolignan isomers. The 3 more important isomers are silybin (or silibinin), silydianin, and silychristin. Silybin is functionally the most active of these compounds. This group of flavonoids has been extensively studied and they have been used as hepato-protective substances for the mushroom Amanita phalloides intoxication and mainly chronic liver diseases such as alcoholic cirrhosis and nonalcoholic fatty liver. Hepatitis C progression is not, or slightly, modified by silymarin. Recently, it has also been proposed for SARS COVID-19 infection therapy. The biochemical and molecular mechanisms of action of these substances in cancer are subjects of ongoing research. Paradoxically, many of its identified actions such as antioxidant, promoter of ribosomal synthesis, and mitochondrial membrane stabilization, may seem protumoral at first sight, however, silymarin compounds have clear anticancer effects. Some of them are: decreasing migration through multiple targeting, decreasing hypoxia inducible factor-1α expression, inducing apoptosis in some malignant cells, and inhibiting promitotic signaling among others. Interestingly, the antitumoral activity of silymarin compounds is limited to malignant cells while the nonmalignant cells seem not to be affected. Furthermore, there is a long history of silymarin use in human diseases without toxicity after prolonged administration. The ample distribution and easy accessibility to milk thistle-the source of silymarin compounds, its over the counter availability, the fact that it is a weed, some controversial issues regarding bioavailability, and being a nutraceutical rather than a drug, has somehow led medical professionals to view its anticancer effects with skepticism. This is a fundamental reason why it never achieved bedside status in cancer treatment. However, in spite of all the antitumoral effects, silymarin actually has dual effects and in some cases such as pancreatic cancer it can promote stemness. This review deals with recent investigations to elucidate the molecular actions of this flavonoid in cancer, and to consider the possibility of repurposing it. Particular attention is dedicated to silymarin's dual role in cancer and to some controversies of its real effectiveness.

Long-term remission in advanced stage hepatocellular carcinoma? A chance for cure?

Liver resection, transplantation, and local ablation are potential curative treatment options but can only be offered to patients with early stage hepatocellular carcinoma (HCC). Patients with macrovascular tumor invasion and extrahepatic metastases are candidates for palliative systemic therapies. Achieving radiological complete response can be associated with long-term remission and excellent outcome. However, despite recent advancements in the medical treatment of advanced stage HCC, complete remission with available systemic treatment options still remains a rare event. This review summarizes data on radiological complete response to systemic therapies and discusses issues that may complicate the goal of achieving cure in advanced stage HCC.

Complete response of advanced hepatocellular carcinoma to sorafenib: another case and a comprehensive review

Since sorafenib was introduced in 2007 for treating advanced hepatocellular carcinoma (HCC), 15 patients have achieved a complete response (CR) in advanced HCC. However, only four of these reports can be regarded as real CRs involving adequate assessments including imaging, serum tumor markers, and histologic examinations of completely resected specimens. A 54-year-old man with hepatitis C virus (HCV)-related liver cirrhosis (LC) presented to our unit. A CT scan demonstrated a 3.8-cm arterial hypervascular/portal-washout mass in the right lobe and invasion in the right portal vein. Twelve weeks after beginning sorafenib therapy, the AFP level was normalized and a CT scan showed a prominent decrease in the hepatic mass and a significant decrease in the volume of portal vein thrombosis (PVT). The patient received a right liver hemihepatectomy after 12 months. No viable tumor cells were found in the resected specimen, and there was no thrombotic obstruction of the portal vein. Twelve months later the patient showed no clinical evidence of HCC recurrence. This is the first case of CR in HCC treatment following sorafenib with histologically confirmed HCV-related HCC without LC evidence, HCC with PVT, and a follow-up of longer than 12 months. This case seems to be an extremely unusual clinical outcome in advanced HCC.

Deteriorated portal flow may cause liver failure in patients with hepatocellular carcinoma being treated with sorafenib

We encountered two patients with hepatocellular carcinoma (HCC) who showed rapid progression of liver failure during sorafenib treatment. One had portal vein tumor thrombus (PVTT) and the other developed portal vein thrombosis (PVT) during the treatment, and both of them experienced the elevation of serum lactate dehydrogenase (LDH) concentration during the administration of sorafenib. Their clinical courses indicate that the liver failure might have been caused by sorafenib-induced liver hypoxia, being amplified in the circumstances with reduced portal flow. To our best knowledge, all the reported patients who achieved complete remission (CR) during sorafenib monotherapy had a condition that could decrease portal blood flow. We hypothesized that pathogenesis of disease may be similar in HCC patients who achieve CR and those who experience liver failure while on sorafenib. Sorafenib treatment of patients with HCC and deteriorated portal flow may be a double-edged sword.

Sorafenib for the treatment of hepatocellular carcinoma with portal vein tumour thrombosis: a systematic review of comparative studies

Sorafenib is the first-line treatment of choice for advanced hepatocellular carcinoma (HCC). However, the benefits of sorafenib in HCC patients with portal vein tumour thrombosis (PVTT) remain uncertain. Until now, a total of eight comparative studies have been identified for this systematic review. Four retrospective studies showed that hepatic arterial infusion chemotherapy, hepatic resection, and three-dimensional conformal radiotherapy might be superior to sorafenib in improving the overall survival. Two ongoing randomised controlled trials (RCTs) will compare the outcomes of transarterial chemoembolisation or radioembolisation with those of sorafenib for the treatment of HCC with PVTT. In addition, two completed RCTs found that additional use of cryotherapy or radiofrequency ablation could prolong the survival of patients receiving sorafenib. In conclusion, the clinical efficacy of sorafenib in HCC patients with PVTT has been widely challenged by other interventions. However, further well-designed RCTs are necessary to confirm the findings of retrospective analyses. Cryotherapy or radiofrequency ablation may be considered as an adjunctive therapy in such patients, if sorafenib is prescribed.

Long-term complete response of advanced hepatocellular carcinoma treated with multidisciplinary therapy including reduced dose of sorafenib: case report and review of the literature

An 83-year-old man underwent computed tomography during a routine check-up due to a history of surgical treatment for pancreatic cancer. Two tumors were detected in the anterior segment of the liver. A needle biopsy of the larger tumor was performed, and pathological examination showed that the tumor was a poorly differentiated hepatocellular carcinoma. Resection was not performed considering the patient's poor physical condition. Thus, transcatheter arterial chemoembolization and radiofrequency ablation of the tumors were performed. Three months later, residual tumor of the larger lesion and multiple pulmonary metastases were detected. This time, continuous hepatic arterial infusion chemotherapy was performed. Although the pulmonary metastases markedly reduced, tumor thrombi appeared in the right portal vein on computed tomography. Finally, sorafenib was administered, which led to disappearance of the tumor thrombi and no other signs of recurrence 8 months after initiation of sorafenib on computed tomography. Although sorafenib administration has continued at reduced doses of 200 mg per day or less due to hypertension, complete response has persisted for the past 34 months. It is noteworthy that sorafenib has been given at reduced doses, but a long-term complete response is maintained in a patient who had portal tumor thrombi and distant metastasis. Herein, we present this rare case of advanced hepatocellular carcinoma controlled with reduced doses of sorafenib following multidisciplinary therapy, describe our single center experience with sorafenib use in patients with hepatocellular carcinoma, and review previous reports that focused on dose reduction of sorafenib.