Epstein-Barr virus-associated smooth muscle tumor of the tonsil

Case history on Epstein-Barr Virus-associated smooth muscle tumor (EBV-SMT) of cranio-cervical junction in an immunocompetent patient

Epstein-Barr virus-associated smooth muscle tumor (EBV-SMT) is a rare mesenchymal tumor that almost exclusively occurs in immunocompromised hosts. Here, we report a 75-year-old Taiwanese woman without definite immune-deficient history presenting with progressive occipital neuralgia, low cranial nerve deficits (CN9-12) and cervical (C1-C5) radiculopathy. Magnetic resonance imaging revealed a 4.5*4.0*6.7 cm infiltrating mass occupying posterior skull base and C1-C2 vertebra and C1-5 epidural extension with bone destruction and vertebral artery (VA) encasement. There was also a synchronous 2.7 cm tonsillar tumor. A two-stage operation for cranio-cervical tumor excision and stabilization was performed. Tumor was confirmed directly arising from VA intraoperatively. Pathology reported a spindle cell neoplasm and the diagnosis of EBV-SMT was confirmed by EBER (EBV-encoded small RNA) in situ hybridization. An immune survey and reconstruction should be conducted for patient with EBV-SMT. A near-total resection of tumor may be beneficial for local control, however, the role of surgical resection in treating CNS EBV-SMT remains to be determined.

Epstein-Barr virus (EBV) status in colorectal cancer: a mini review

Epstein-Barr virus (EBV) is a well-characterized oncovirus, associated with several malignancies. The complex and heterogeneous nature of colorectal cancer (CRC) has led to many epidemiological causal associations with CRC. However, a direct causal link between microbial infections and CRC has not been established yet. Our review indicates that the current evidence for the presence and role in EBV in CRC is insufficient and contradictory. The design of the analyzed studies, sample size as well as methodology used for EBV detection varied markedly and consequently may not lead to meaningful conclusions. The presence of EBV in other colorectal tumors (lymphomas, smooth muscle tumors) is in line with their status at other anatomic locations and may have therapeutic implications with EBV-specific vaccines. On the other hand, studies exploring EBV in colorectal adenoma-carcinoma sequence and its molecular genetic characteristics are largely missing and may significantly contribute to a better understanding of the role of EBV in CRC.

Laryngeal Epstein-Barr Virus-Associated Smooth Muscle Tumor in an Undernourished Child

Smooth muscle tumors associated with Epstein-Barr virus infections (EBV-SMT) of laryngeal origin are exceedingly rare and have been reported in few adult patients, but not in children. This reported case describes a lesion found in the larynx of an 8-year-old Guatemalan undernourished girl. Microscopically, the lesion showed a highly cellular mesenchymal spindle cell tumor, containing frequent lymphocytes. The immunohistochemical analysis revealed positivity for α-smooth muscle actin and h-caldesmon. In addition, most of the tumor cells were positive for EBV by in situ hybridization. To the best of the author's knowledge, this is the first literature-reported case of laryngeal EBV-SMT occurring in an undernourished child.

EBV-associated hepatic smooth muscle tumor of uncertain biologic behavior after heart transplantation in a pediatric patient: case report

Epstein-Barr virus-associated smooth muscle tumor (EBV-SMT) is a rare neoplasm recognized in immunocompromised patients. There are less than 30 cases of EBV-SMT reported in pediatric population following solid organ transplantation. Herein, we report a case of an 8-year-old female who was incidentally noted to have multiple lesions in the liver 8 years after heart transplantation. The tumor was composed of a cellular proliferation of spindle-shaped cells with low mitotic activity. The diagnosis of EBV-SMT was confirmed by in situ hybridization for EBV-encoded small RNA (EBER) transcripts. Multiple additional lesions were detected by whole body positron emission tomography-computed tomography (PET-CT) scan 4 months after the initial finding of the hepatic lesions. Immunosuppression was switched to a mechanistic target of rapamycin (mTOR) inhibitor. We conclude that EBV-SMT should be included in the differential diagnoses in post-transplantation patients and further investigations should be performed to evaluate additional lesions.