Early hepatocellular carcinoma and dysplastic nodules

Area of Science:

• Hepatology
• Oncology
• Pathology

Background:

• Small nodular lesions like dysplastic nodules (DNs) and early hepatocellular carcinoma (HCC) are common in cirrhotic liver tissues.
• High-grade DNs and early HCCs share similarities, making differentiation difficult.
• These lesions are frequently found in noncancerous liver tissues resected with HCC and in explant cirrhotic livers.

Purpose of the Study:

• To highlight the diagnostic challenges in differentiating high-grade DNs from early HCC.
• To identify key pathological features aiding in the distinction between these lesions.
• To elucidate the proposed multistep progression of HCC from DNs in cirrhotic livers.

Main Methods:

• Review of pathological criteria for classifying dysplastic nodules (low-grade and high-grade).
• Analysis of cytological and architectural atypia in high-grade DNs and early HCCs.
• Evaluation of tumor cell invasion into intratumoral portal tracts (stromal invasion) as a diagnostic marker.

Main Results:

• High-grade DNs exhibit varying degrees of cytological or architectural atypia.
• Early HCCs are often indistinctly nodular and well-differentiated, complicating diagnosis.
• Stromal invasion is identified as a crucial feature for distinguishing early HCC from high-grade DNs.

Conclusions:

• The pathological diagnosis of high-grade DNs and early HCC remains controversial.
• Stromal invasion serves as a valuable diagnostic clue for early HCC.
• HCC in cirrhotic livers is suggested to develop through a multistep process originating from DNs.