Spontaneous regression of hepatocellular carcinoma: A mini-review

Abstract

Spontaneous tumor regression is an extremely rare phenomenon in the oncology field. However, there are several case reports resulted in the regression of hepatocellular carcinoma (HCC) and the accumulation of clinical information and analyses of the mechanism can contribute to the development of a novel therapy. For this purpose, we have carefully reviewed 23 cases of spontaneously regressed HCC published in recent 5 years and our case. The information regarding the tumor size, tumor marker, treatments, etc., have been summarized. The mechanism of spontaneous regression has been discussed to date and presumed to be due to many factors, including hypoxia and immunological reactions. In this careful review of the 24 cases based on the clinical information, hypoxia, systemic inflammation, and both upon spontaneous regression were seen in 3, 8, and 4 cases, respectively among the 15 cases for which the information regarding the proposed mechanisms are available. Recent development of immunotherapeutic approaches in oncology shows promising results, therefore, accumulation of additional cases and analysis of mechanisms underlying the spontaneous regression of HCC are essential and could lead to the development of a new generation of immunotherapies including antibodies directed against immune reactions.

Complete response by vitamin K2 analog monotherapy in sorafenib‐failure advanced hepatocellular carcinoma: A case report

“…The other possible mechanisms of antitumor response in this case might be spontaneous regression of HCC or delayed response of sorafenib. Immunological reactions are reported to be the main mechanism of spontaneous regression of HCC, and in the present case, the discontinuation of sorafenib therapy might have changed the antitumor environment and immunity. In the practical setting, there are some cases of delayed response of sorafenib .…”

Stereotactic Body Radiation Therapy–Induced Abscopal Effect on Hepatocellular Carcinoma After Treatment for Lung Cancer: A Case Report

“…It is hypothesized that systemic immunologic reactions have the potential to cause spontaneous HCC regression. (5) Treatment of synchronous HCC was obviated in this patient by complete regression after radiation to his lung tumor. Interestingly, the patient did not have benefit of increased systemic stimulation as there was no clinical indication for immunotherapy.…”

“…We describe a case of the abscopal effect after radiation to a second primary cancer. It is hypothesized that systemic immunologic reactions have the potential to cause spontaneous HCC regression . Treatment of synchronous HCC was obviated in this patient by complete regression after radiation to his lung tumor.…”

Spontaneous regression of hepatocellular carcinoma with reduction in angiogenesis‐related cytokines after treatment with sodium‐glucose cotransporter 2 inhibitor in a cirrhotic patient with diabetes mellitus

“…Possible mechanisms for spontaneous regression of cancer include immune mediation, tumor suppression by growth inhibitory factors, tumor necrosis, and/or angiogenesis inhibition . Spontaneous regression is also observed in patients with HCC . However, the mechanisms for HCC remain unclear.…”