Cytoplasmic liver cell inclusions--a typical feature of porphyria cutanea tarda--are absent in porphyria-related hepatic neoplasias.

Crystalline cytoplasmic needle-shaped inclusions in hepatocytes are considered to represent a specific morphological feature of porphyria cutanea tarda (PCT) and experimental PCT-like porphyrias. The cytoplasmic inclusions, however, are absent in hyperplastic hepatic nodules and hepatocellular carcinomas arising in the course of these conditions. It is assumed that porphyrins and related substances accumulated in hyperplastic and neoplastic hepatic lesions differ from those found in non-neoplastic liver tissue: the highly carboxylated porphyrins are stored in both sites, the crystal-forming substance only in non-proliferating liver tissue.