Patterns of hepatotoxicity after chemotherapy for colorectal cancer liver metastases.

AIM: The aim of this study was to assess chemotherapy associated hepatotoxicity after 3 months' treatment and to correlate patterns of hepatotoxicity with perioperative morbidity. METHODS: Liver specimens of 50 patients with liver metastases from colorectal cancer receiving XELOX or FOLFOX4 for six cycles and 13 specimens of non-chemotherapy patients subjected to liver resection were analyzed. Different patterns of hepatotoxicity were evaluated according to widely accepted pathohistological scores. Furthermore, the histomorphological findings were correlated with perioperative morbidity. RESULTS: Steatosis grades did not differ among the chemotherapy treated groups and non-chemotherapy patients. Chemotherapy showed an independent effect on fibrosis stage. Age and chemotherapy were independently associated with sinusoidal dilatation. Centrilobular vein fibrosis correlated with administration of chemotherapy. Higher fibrosis stages were associated with increased transfusion requirements. CONCLUSION: XELOX and FOLFOX4 do not correlate with the development of steatosis or steatohepatitis. We do not detect a difference in liver injury between the XELOX and FOLFOX4 group. Although 5-fluorouracil based chemotherapy may cause profound changes in liver parenchyma, it can be safely applied. However, age and oxaliplatin predispose for the development of sinusoidal dilatation; therefore caution must be taken in old patients treated with oxaliplatin.

The cellular lesion of humoral rejection: predominant recruitment of monocytes to peritubular and glomerular capillaries.

Accumulation of inflammatory cells within capillaries is a common morphologic feature of humoral renal allograft rejection and is most easily appreciated if it occurs in glomeruli. The aim of our study was to determine the amount and composition of immune cells within glomeruli and peritubular capillaries (PTC) in cellular and humoral allograft rejection. Immunofluorescent double-labeling for CD31 and CD3 or CD68 was used for phenotyping and enumerating immune cells within glomeruli and PTC. The major findings are: (1) accumulation of immune cells in PTC is far more common than it would be anticipated based on the assessment by conventional histology; (2) it is not the absolute number of immune cells accumulating within capillaries, but rather the composition of the intracapillary cell population that distinguishes humoral rejection from cellular rejection and (3) in C4d positive biopsies a predominantly monocytic cell population accumulates not only within glomeruli but also within PTC. The median value of monocyte/T-cell ratio within PTC was 2.3 in C4d positive biopsies but only 1 (p = 0.0008) in C4d negative biopsies. Given their prominent presence within capillaries and their extensive biological versatility monocytes might contribute to the capillary damage observed in acute and chronic allograft rejection.

BMI-1: a protein expressed in stem cells, specialized cells and tumors of the gastrointestinal tract.

Recently, BMI-1 was identified as a protein downregulating p16ink4a and mandatory for the continued existence of several stem cell compartments like hematopoietic and neural stem cells. In this study we investigated BMI-1 expression as a potential stem cell marker of the gastrointestinal tract. We found weak expression in the isthmus region of the stomach, and moderate expression in crypts of the intestines, whereas intestinal surface epithelial cells were weakly positive or negative for BMI-1. In addition, a variety of highly differentiated cells such as parietal cells, neuroendocrine cells of the pylorus, Paneth cells and a subset of goblet cells were moderately to strongly positive for BMI-1. Furthermore, we detected strong expression in gastrointestinal neoplasias. This expression pattern indicates a correlation of BMI-1 expression with gastrointestinal stem cells as well as numerous specialized cell types and points to a role of this protein in cellular differentiation in addition to that of stem cell maintenance. Besides, our results imply a role for BMI-1 in the tumorigenesis of gastrointestinal cancer.

A rare cause of anemia due to intestinal tuberculosis in a renal transplant recipient.

A renal transplant recipient with stable allograft function presented with massive hemorrhagic diarrhea and severe anemia. No microbial infection could be found in stool cultures. Early colonoscopy showed severe colitis with ulceration. Histological samples confirmed granulomatous inflammation with acid-resistant Ziehl-Neelson-positive microorganisms of mycobacterial type. Polymerase chain reaction (PCR) analysis of native mucosal biopsies specified the infectious organism as Mycobacterium tuberculosis complex. The patient responded well to antimycobacterial therapy and was still asymptomatic after 6 months with a stable graft function. Our case shows that tuberculosis can be a severe clinical problem in transplant recipients. Most of the patients with intestinal tuberculosis, reported to literature, were diagnosed post mortem or after explorative laparotomy and bowel resection. Thus, intestinal tuberculosis should be considered when a transplant recipient shows abdominal symptoms with no clear evidence of another infection. Proper diagnosis and treatment resulted in a beneficial outcome in our patient.