Liver cancer is the second leading cause of cancer death worldwide, with hepatocellular carcinoma (HCC) being the most common type of primary malignant liver tumour, with a typically poor prognosis, growing incidence and a well-documented relationship with chronic inflammation factors of the liver tissue. Despite the fact that family medical history has been identified as a risk factor for the development of HCC, its significance in terms of etiopathogenesis and prognosis is not well documented. With a view to contributing to this discussion, we will report the clinical case of two identical twins with HCC, both diagnosed within a short period of time, by providing relevant clinical data, and relating this to other medical literature reports that could contribute to a deeper understanding of this illness.