Redistribution of thorotrast into a liver allograft several years following transplantation: a case report

Abstract

Thorotrast was used as a radiographic contrast agent in the United States from about 1930 to the mid-1950 s. Its use was discontinued when it was recognized that its radioactivity caused long-term deleterious effects. Such long-term sequelae of intravascular Thorotrast injection include, most notably, hepatic and hematologic malignancies and hepatic fibrosis. Some patients who had received Thorotrast subsequently received liver transplants. However, it was not known whether or not Thorotrast could become redistributed within the new allograft. A single report in 1994 demonstrated that radioactivity was detected by gamma-ray spectroscopy in liver allografts shortly after transplantation. No report has identified Thorotrast in the allografts of long-term transplant survivors, and the redistribution of Thorotrast into allografts has not been documented histologically or by electron microscopy. We report a case of recurrent Thorotrast into a liver allograft 10 years post-transplant. We evaluated the native liver and allograft specimens for the presence of thorium utilizing light microscopy, electron microscopy and electron X-ray microanalysis. This case report demonstrates for the first time the redistribution of Thorotrast into a long-surviving liver allograft using histologic, electron microscopic and X-ray microanalysis techniques.

In-vitro cell exposure studies for the assessment of nanoparticle toxicity in the lung—A dialog between aerosol science and biology

“…For example, the liver Kupffer cells play a primary role in the systemic clearance of bacteria escaping the gastrointestinal tract, proving for protection against system infection. Consequently, Kupffer cells are a major site of accumulation of nanomaterials reaching the blood circulation (Odegaard et al, 1978;Moghimi & Hunter, 2001;Krasinskas et al, 2004;Sadauskas et al, 2009), and nanomaterials can remain in these cells for decades. Very little, however, is understood about the potential for nanoparticle accumulation in Kupffer cells to disrupt their normal bacterial clearance function following low, chronic environmental exposures.…”

Cellular recognition and trafficking of amorphous silica nanoparticles by macrophage scavenger receptor A

“…Indeed, the rapid sequestration of ENPs from the circulation by hepatic and splenic macrophages is a major obstacle for efficient targeting of ENP-based therapeutics to peripheral tissues (Moghimi et al 2001). For some poorly soluble particles, macrophages act as a cumulative reservoir, resulting in chronic accumulation of particles that can persist for months in rodents and decades in humans (Odegaard et al 1978;Krasinskas et al 2004;Sadauskas et al 2009). Pro-inflammatory signaling cascades initiated by activated phagocytes play an important role in the innate immune defense against foreign particulates, but sustained inflammation can also lead to tissue damage and human disease (Ding et al 2002;Hamilton et al 2008).…”

The Uneven Irradiation of a Target Cell and Its Dynamic Movement Can Mathematically Explain Incubation Period for the Induction of Cancer by Internally Deposited Radionuclides

“…However, the current study suggests that a short exposure period of a target cell and its movement outside the range of radiation exposure from unevenly deposited radionuclides are responsible for radiation carcinogenesis induced by internally deposited alpha-emitters. Histologically, Thorotrast is often present in macrophages (Goto et al 2002) and redistribution happens (Krasinskas et al 2004). However, eventually the major part of the Thorotrast deposit becomes associated with areas of dense collagen deposition, which induces architectural remodeling of the liver through ischemic changes.…”