Unexpected Spontaneous Regression Of Extensively Diffused Hepatocellular Carcinoma
Hirata, T., Endo, S., Shirane, N., Kawaguchi, S., & Ohno, K. (2025). Unexpected Spontaneous Regression of Extensively Diffused Hepatocellular Carcinoma. Cureus, 17(2), e79366. https://doi.org/10.7759/cureus.79366
View Original Source →Abstract
Spontaneous regression (SR) of malignant tumors is defined as the partial or complete reduction of a tumor without medical intervention. This unusual phenomenon has been reported in various types of malignancies. We present a rare case of a 73-year-old woman with untreated chronic hepatitis C who was diagnosed with extensively diffused hepatocellular carcinoma (HCC) accompanied by a tumor thrombus in the left branch of the portal vein. Remarkably, extensive tumor regression occurred under palliative care. This case highlights the potential mechanisms responsible for SR of HCC, including tumor hypoxia, immune activation, and systemic inflammatory responses, and emphasizes the need for further research to clarify these mechanisms.
Case Details
Disease Location
Liver
Personal Characteristics
73-year-old japanese woman with untreated chronic hepatitis c. Smoking history of 37.5 pack-years
Clinical Characteristics
Presented with complaints of abdominal distension and a 5 kg weight loss over the course of one month. CT demonstrated an irregular, cirrhotic liver with a large, 150-mm diffuse hcc replacing the left lobe. The lesion appeared hyperattenuated in the arterial phase and hypodense in the portal venous phase. Multiple smaller hcc lesions were observed in the right lobe, and a tumor thrombus was identified in the left branch of the main portal vein. Tumor markers were markedly elevated. She ceased her 37.5-pack-year smoking habit immediately following her diagnosis of hcc.
Remission Characteristics
Seven months after the initial diagnosis revealed marked regression of the hypervascular hcc. The tumor thrombus in the left branch of the main portal vein had disappeared. Her tumor markers were notably reduced.
Treatment & Mechanisms
Proposed Remission Mechanisms
The tumor thrombus in the left branch of the main portal vein likely caused ischemia and subsequent necrosis of the tumor. Furthermore, the patient’s decision to quit smoking may have reduced oxidative stress and enhanced their natural immune responses against the tumor, contributing to sr. These findings suggest that both tumor hypoxia and immune activation may have played critical roles in the sr
Non-Clinical Treatment
Smoke cessation