Inflammatory pseudotumor after liver transplantation

An inflammatory myofibroblastic tumor in the transplanted liver displaying quick wash-in and wash-out on contrast-enhanced ultrasound: A case report

RATIONALE

Inflammatory myofibroblastic tumor (IMT) is an uncommon mesenchymal neoplasm, and its presence in a grafted liver is exceedingly rare.

PATIENT CONCERNS

A 54-year-old woman was admitted to our hospital with a half-month history of intermittent melena. She had undergone deceased-donor liver transplantation (LT) for hepatitis B virus related liver cirrhosis without hepatocellular carcinoma 5 months previously.

DIAGNOSIS

Laboratory examination showed impaired liver and renal functions and Epstein-Barr virus (EBV) infection, but tumor markers within normal ranges. Gastroscopy showed esophageal varices. Ultrasound and computed tomography angiography revealed an ill-defined and irregular solitary lesion in the porta hepatis, encasing both the portal vein and the hepatic artery. The lesion was characterized by arterial hyper-enhancement and hypo-enhancement in the remaining phases with contrast-enhanced ultrasound (CEUS). The lesion was finally confirmed as an IMT by ultrasound-guided biopsy.

INTERVENTION

The patient received conservative treatment, including immunosuppression, endoscopic variceal ligation, antibiotics, steroids, and antiviral agents.

OUTCOME

The patient's gastrointestinal bleeding was controlled, but the symptoms associated with portal hypertension worsened. Attempts to perform a transjugular intrahepatic portosystemic shunt were unsuccessful, and she unfortunately died soon after.

LESSONS

A differential diagnosis of IMT should be considered in LT recipients presenting with EBV infection, normal tumor markers, and a de novo hepatic lesion with quick wash-in and wash-out on CEUS. Ultrasound is associated with the advantages of convenience and nonionizing radiation, and should thus be the priority approach for monitoring transplanted liver.

Inflammatory Pseudotumors After Stem Cell Transplantation

Inflammatory pseudotumors (IPT) are rare tumors that occur in various organs and tissues. The clinical picture varies from the more frequent benign lesions to rare malignant tumors with distant metastases. IPTs associated with hematopoietic stem cell transplantation (HSCT) is rarely reported. In this article, we review the reports of IPT after HSCT. We also review the possible factors involved in the pathogenesis. IPT may be rare but they are a potentially serious complication of HSCT. A knowledge of these entities and insistence on a definitive biopsy of mass lesions in the post-HSCT period can avoid unnecessary treatment such as radical surgery, chemotherapy or radiotherapy.

Synchronous posttransplant lymphoproliferative disorder and inflammatory myofibroblastic tumor of the lung in a 2-year-old liver transplanted boy: a case report

Inflammatory myofibroblastic tumor is a rare benign lesion found mostly in children and young adults. It originates from the lung, abdominopelvic region, and retroperitoneum. The tumor is composed of myofibroblasts and inflammatory cell infiltration in the tissue. The cause and pathogenesis of this tumor are not completely understood. Epstein-Barr virus has been held responsible in some reported cases of inflammatory myofibroblastic tumors. Another tumor (which is known to be related to the Epstein-Barr virus) is posttransplant lymphoproliferative disorder. We report the case of a 2-year-old boy who underwent a liver transplant at the age of 9 months (the donor was his mother) because of biliary atresia. At 11 months after transplant, we detected posttransplant lymphoproliferative disorder and inflammatory myofibroblastic tumor concurrently. This entity is presented to highlight possible Epstein-Barr virus involvement in inflammatory myofibroblastic tumor of lung.

Inflammatory myofibroblastic tumor of the liver in children

Inflammatory pseudotumors, now more aptly termed inflammatory myofibroblastic tumors (IMTs), are uncommon benign neoplasms, which have been reported in most organs and tissues in the body. Originally described and commonly found in the lung, they are also found in the liver of children and adults. We review the literature and analyze the features of the hepatic IMTs reported in children, along with a case report of a 15-month-old boy who had a persistent IMT in the liver and underwent surgical resection for the same following a trial of conservative management.

Inflammatory myofibroblastic tumor of the liver following renal transplantation

Inflammatory myofibroblastic tumor (IMT), previously named inflammatory pseudotumor, is a benign lesion, the exact etiology of which remains obscure; immunosuppression and infections have been speculated to be responsible for the development of pseudotumor. IMT associated with transplantation is rarely reported; we report the first case of IMT of the liver in a renal transplantation patient, who presented with symptoms of abdominal pain. The findings of computed tomography suggested hepatocellular carcinoma or liver abscess, and surgical resection was performed. The lesion was pathologically diagnosed as IMT.

Bilateral infiltrating renal inflammatory pseudotumor responsive to corticosteroid therapy

Inflammatory pseudotumor (IPT) is a quasi-neoplastic lesion that most commonly involves the lung, but has been shown to occur in nearly every tissue type. Renal involvement is very uncommon. We report the second case of IPT ever published presenting as bilateral infiltrating renal masses. Although most renal IPTs were treated with nephrectomy, our patient was managed successfully with conservative steroid treatment, thereby avoiding the alternative of dialysis or kidney transplantation.

Inflammatory pseudotumor following hematopoietic stem cell transplantation: a new case and review of the literature

Inflammatory pseudotumor (IPT) is a rare tumor that occurs in various organs and tissues. The clinical picture varies from the more frequent benign lesions to the rare malignant tumors with distant metastases. IPT associated with hematopoietic stem cell transplantation (HSCT) is rarely reported. In this article, we review the reports of IPT after HSCT and describe the first case of bladder IPT. We also review the possible factors involved in the pathogenesis. IPT might be rare but it is a potentially serious complication of HSCT. It should be considered in patients with otherwise unexplained inflammatory symptoms or signs or with any mass lesion in the post-HSCT period. A knowledge of this entity and insistence on a definitive biopsy of mass lesions in the post-HSCT period can avoid unnecessary treatment such as radical surgery, chemotherapy or radiotherapy.

Complex genomic rearrangement of ALK loci associated with integrated human Epstein-Barr virus in a post-transplant myogenic liver tumor

Epstein-Barr virus (EBV) is a ubiquitous viral agent, well known to be associated with lymphoid, epithelial, and smooth-muscle malignancies in immunocompromised individuals. This report describes a 10-year-old patient with an EBV-related liver tumor occurring after kidney transplantation. The neoplasm presented a phenotypic spectrum, ranging from a smooth-muscle tumor to an inflammatory pseudotumor (IPT). The neoplastic cells failed to disclose CD21, CD35, or ALK expression, the latter confirmed by reverse-transcription polymerase chain reaction. Cytogenetic analysis revealed a single clonal cell population showing 46,XY,del (2)(p23),der(3)t (2;3)(p23;q29),der(21) t(Y;21)(q12;p13) karyotype. By metaphase FISH analysis, the neoplastic cells demonstrated the presence of two molecularly different but related aberrant clones, one with the loss of one ALK allele and the second with translocation of the 3'end of ALK kinase domain on the der(3) chromosome. Using FISH with an EBV-specific and 3'end ALK DNA probes, a co-localization of the viral DNA and the ALK sequences was found on the der(3) chromosome. Metaphases with loss of rearranged ALK did not show integrated virus; instead, viral particles together with an associated 3'end ALK domain formed an ex-chromosomal, episomal-like type configuration. The interphase study, using dual-color 5'/3' end ALK FISH assay, revealed 30% of nuclei with only one fused signal, confirming the total loss of one ALK allele in the subset of tumor cells. A combined immunofluorescence and FISH study indicated this separate clonal variant to correspond to desmin-positive smooth-muscle cells. In contrast, desmin-negative myofibroblasts showed the presence of both normal and rearranged ALK alleles. Our results indicate that ALK locus may be a target of EBV integration, a hitherto unreported finding. Although the sustained clonal expansion in EBV-related smooth-muscle tumors/IPTs may depend on functions provided by the EBV oncogenic proteins, the tumor phenotype may be further modified by the secondary genomic rearrangements imposed by the virus during and/or after the integration event. In this respect, the observed phenotypic heterogeneity most likely reflects divergence during neoplastic progression, with the subsequent expansion of morphologically and molecularly distinct but cytogenetically related clones.

Clostridium difficile colitis associated with inflammatory pseudotumor in a liver transplant recipient

The aim of this report is to describe a rare complication of clostridium difficile (CD) disease, the occurrence of an inflammatory pseudotumor that caused intestinal obstruction in a liver transplant recipient. A 9-month-old girl underwent liver transplantation for biliary atresia. She was given tacrolimus as primary immunosuppressive therapy. Three months after liver transplantation, she presented with febrile protracted bloody diarrhea and failure to thrive. A diagnosis of post-transplant lymphoproliferative disease associated with Epstein-Barr virus infection was initially made on histological examination of duodenal biopsies. Tacrolimus was discontinued. Despite treatment with anti-CD20 monoclonal antibodies the child's condition deteriorated and she presented with intestinal occlusion. A mass at the ascending colon was seen on the computed tomography scan mimicking lymphoma and the child underwent surgical laparotomy. Histological examination of the mass showed typical pathological lesions of inflammatory pseudotumor and CD pseudomembranous colitis. Diagnosis of CD disease was confirmed upon the identification of CD toxin A in stools. She was successfully treated by metronidazole and gamma-globulin perfusions. Delayed diagnosis and anti-CD20 monoclonal antibodies therapy (associated with hypogammaglobulinemia) possibly played a major role in the severity of CD pseudomembranous colitis and in the occurrence of an inflammatory pseudotumor.