Endobronchial leiomyoma: an unusual non-defining neoplasm in a patient with AIDS

Abstract

SUMMARYSmooth muscle neoplasms are more frequent in human immunodeficiency infected children than in HIV seropositive adults. Endobronchial leiomyoma is a rare benign tumor in HIV infected adult patients. Epstein-Barr virus (EBV) has been implicated in the pathogenesis of these tumors. Here we describe an adult patient with HIV infection with atelectasis of the left upper pulmonary lobe as the first clinical expression of an intrabronchial leiomyoma. In this case, we can not show the association with EBV. Our report suggests that smooth muscle tumors as leiomyoma should be included in the differential diagnosis of endobronchial masses in AIDS patients.

AIDS-Related EBV-Associated Smooth Muscle Tumors: A Review of 64 Published Cases

“…Although EBER was negative in two SMT cases [9, 19] and EBV testing of the tumors were not performed in five patients [8, 37, 42], these HIV-related SMT were included in this paper. Also included was one case of an EBV-positive myopericytoma [35].…”

“…It may be that LMP expression is below that detected by immunohistochemistry in these tumors. Although there were some inconsistent results in cases tested for EBNA-2 and LMP-1 [7, 19, 20, 22, 27, 30, 45], it would appear that overall EBV-SMT demonstrate Type III latency. …”

“…Based on published findings, EBV-SMT has a nodular, centrally ulcerated appearance on endoscopic examination [42]. Those with endobronchial tumors may present with cyanosis, fever, and/or pulmonary infections unresponsive to antibiotics [6, 19, 34]. Endobronchial tumors, if large enough, may be visualized on bronchoscopic examination and surgically ablated.…”

“…It has been suggested that the presence of CD21 (EBV receptor) on smooth muscle cells is a putative prerequisite for EBV infection [55], but this is unlikely since the mechanism of EBV entry into different cell types may be by different routes, and it is also uncertain whether the CD21 antigen found on smooth muscle cells is similar to that found on B lymphocytes [56]. Immunohistochemical staining for LMP-1 in addition to EBER was performed in 7 cases [16, 19, 20, 22, 27, 30]. Only one of the cases demonstrated weak immunoreactivity for LMP-1 [22].…”

“…Only one of the cases demonstrated weak immunoreactivity for LMP-1 [22]. One of these cases, an endobronchial leiomyoma arising in a patient with AIDS, was negative for LMP-1 and EBER [19]. The presence of EBV in SMT cells not only supports a role for this herpes virus in the pathogenesis of these tumors, but also serves as a useful diagnostic marker.…”