A Rare Case of Sinonasal Lymphoepithelial Carcinoma Presented With Clinically Stage IV Disease

Abstract

Sinonasal lymphoepithelial carcinoma (SLEC) is an extremely rare malignancy. We present a case of SLEC in a 77-year-old man who presented with nasal congestion and persistent sinusitis. Imaging revealed a large right nasal mass involving right paranasal sinuses along with bulky bilateral cervical lymphadenopathy. In addition, there was a fluorodeoxyglucose avid L1 vertebral lesion. Biopsy of nasal mass and cervical lymph nodes showed syncytial growth of tumor cells in a lymphoplasmacytic background. Immunohistochemical stains showed positivity for pankeratin, CK5/6, epithelial membrane antigen, p40 (focal), and p63 (focal). An Epstein-Barr virus-encoded RNA by in situ hybridization was strong and diffusely positive. Based on these pathologic findings and considering the location of tumor, diagnosis of SLEC was rendered. L1 vertebral body lesion was clinical and radiologically considered to be a metastasis. Correlation with radiology to determine the exact location of tumor is extremely important for correct diagnosis due to its histopathologic similarities with relatively more common undifferentiated type of nasopharyngeal carcinoma. No standard treatment protocol has been established for this tumor yet. To our knowledge, this is first ever report of SLEC presented with clinical stage IV disease.

Lymphoepithelial Carcinoma Originated from the Sinonasal Cavity: Case Report and Literature Review

“…Upon suspicion of SNLEC, immunohistochemical testing is important to rule out other differential diagnoses such as melanoma, lymphoma, and sinonasal undifferentiated carcinoma (SNUC). Another way to differentiate SNLEC is that it is not immunoreactive to hematolymphoid, melanoma-related, and neuroendocrine/neuroectodermal markers, as well as stains positive for EMA [ 10 ]. SNUC is also EBV-negative and has a uniquely aggressive clinical disease course histopathologically characterized by prominent tumor necrosis and apoptosis with low syncytial nuclei quality, which differentiates it from nasopharyngeal squamous cell carcinoma and SNLEC [ 5 ].…”

Sinonasal Lymphoepithelial Carcinoma With Aggressive Orbital Invasion

“…Commonly, patients present with nasal obstruction, epistaxis, and facial pain. Tumor invasion into the olfactory bulb, frontal lobe, and possibly brain stem causes anosmia and ageusia, whereas orbital invasion can lead to proptosis and cranial nerve palsies [ 3 ]. Symptoms such as epiphora, blood-tinged tears, and epistaxis were reported in a rare case of LEC of the nasolacrimal duct [ 12 ].…”

“…SNUC, which comes as a diagnosis of exclusion, is highly regarded as an aggressive tumor. Compared to LEC, microscopically, SNUC demonstrates high mitotic activity and necrosis with no association with EBV [ 3 ].…”

“…There is no standard treatment guideline for sinonasal LEC due to the rarity of this tumor and its anatomical complexity with close proximity to vital structures [ 3 ]. Initially, surgery is the treatment of choice; however, radiotherapy should be considered even if there is involvement of lymph nodes because LEC is radiosensitive [ 9 ].…”

“…In most cases, sinonasal LEC presents with locally aggressive disease with or without regional lymph node metastases. It is found to be more common in Southeast Asia [ 3 ]. We report a rare case of LEC in the ethmoid sinus invading the orbit and brain, which initially presented with loss of vision and proptosis.…”