Speakers - 2024

Biography

I am working as a fellow at division of Infectious diseases at University of Louisville Hospital. I belong to Pakistan where I did my internal medicine residency. My interest in infectious diseases paved my way to united states for pursuing my carrier in the field of infectious diseases.

Abstract

Introduction

Epstein-Barr virus associated-smooth muscle tumor (EBV-SMT) is a rare malignancy that is associated with immunocompromised states. Human Immunodeficiency Virus (HIV) is the most common predisposing factor; however, it can occur in post-transplant patients and those with genetic immunodeficiencies. While no precise prevalence data is available, it is estimated to be <2 cases per million.

Case report

A 38-year old female with a past medical history of HIV, adrenal leomyoma that underwent adrenectomy, and nonspecific extraorbital mass was transferred to our facility for increasing size of brain masses in the setting of new-onset seizures, right-lower extremity weakness, and severe headache. CD4 count was found to be 12 with an HIV viral load of 34,100. Initial CT Head showed a left parafalcine extracranial mass, and follow-up CT showed an interval increase in the mass. MRI brain confirmed these findings and revealed a right orbital mass extending to the margin of the right optic nerve canal. CT neck showed a new 2.5cm mass in the region of the left jugular foramen. She underwent bifrontal parietal craniotomy with resection of the extra-axial brain tumor followed by biopsy, which confirmed soft tissue tumor secondary to EBV.

Discussion

EBV-SMTs are rare tumors linked to immunocompromised states, most commonly HIV+ individuals. They primarily occur in the CNS presenting with neurologic symptoms. According to current literature, the tumor immune microenvironment, characterized by hypoxia, acidosis, interstitial hypertension, and vascular insufficiency contributes to the progression of these neoplasms. This microenvironment fosters the production of proteolytic enzymes, growth factors (e.g., VEGF), and inflammatory proenzymes. This hypothesis has also been implicated in pathogenesis of other EBV-associated neoplasms, such as gastric cancer and nasopharyngeal carcinoma. EBV modulates tumor suppressor genes such as p53 and activates pro-carcinogenic pathways like NF-kB. EBV-SMTs often develop near blood vessels, indicating a possible Epstein-Barr viral tropism for vascular smooth muscle.

HIV acquired immunodeficiency syndrome (AIDS) is known to induce an immunocompromised state due to targeted destruction of CD4 T cells, which provides an ideal environment for opportunistic infections such as EBV. While EBV-SMTs have been identified in patients with primary immunodeficiencies, common variable immunodeficiency (CVD), and post-transplant, most cases have been noted in the presence of HIV infection.

Treatment of EBV-SMT is typically resection; however, chemotherapy and radiation therapy have also been utilized. The mTOR inhibitor everolimus has been identified as a potentially effective intervention against EBV-SMT. In addition, the EBV envelope glycoprotein 350 (gp350) has been identified as a specific biomarker for EBV lytic activation. gp350 chimeric antigen receptor (CAR) T cells have shown preclinical efficacy against EBV lymphoproliferation. Finally, limited evidence supports the efficacy of anti-retroviral therapy (ART) in shrinking EBV-SMT tumors.

Conclusion

EBV-SMTs occur in HIV patients with decreased CD4 counts. This case highlights the importance of considering EBV in the differential diagnosis of HIV patients. Early detection of HIV infection, regular CD4 monitoring, and ART management may decrease the risk of these malignancies.