Heavily pigmented renal cell carcinoma: a case report, with review of the literature and differential diagnosis.

Clear cell carcinoma is the most common histotype among renal cell tumors. The prominent vascular network of sinusoidal vessels lined by delicate endothelial cells may often lead to hemorrhagic areas with secondary deposition of chunky birefringent hemosiderin granules. The finding of pigmentation other than iron, and in particular melanin deposits, in renal tumors is a rare occurrence that should lead to differential diagnosis with other primary and metastatic tumors of the kidney.

Phytoestrogens and liver disease.

Phytoestrogens are plant substances that are similar to 17-beta-estradiol and produce estrogenic effects. A protective role in the development of breast and prostate cancer has been hypothesized. Estrogen receptors and their variant forms play a significant role in the pathogenesis of hepatocellular carcinoma (HCC); therefore weak estrogenic substances in the diet may play a role in its development.

Pretransplantation pre-S2 and S protein heterogeneity predisposes to hepatitis B virus recurrence after liver transplantation.

Liver transplantation (LT) in patients with hepatitis B virus (HBV) infection often is complicated by recurrence of infection despite immunoglobulin treatment. To evaluate whether variability in HBV genomic sequences and the target of antibody to hepatitis B surface antigen action in pre-LT samples may be associated with a high recurrence rate, HBV pre-S/S regions of 14 HBV-positive candidates for LT (in 9 of these patients, HBV infection subsequently recurred) were amplified and sequenced. Two hundred ninety-one mutations in 1,167 sequenced nucleotides (24.