Lymphoepithelioma-Like Carcinoma of the Skin with Potential for Sweat Glandular Differentiation

Poorly Differentiated Cutaneous Squamous Cell Carcinoma (cSCC) or Lymphoepithelioma-like Carcinoma of the Skin (LELCS) with Squamous Pearls: A Case Presentation with Emphasis on Histomorphological Features and Classification Debates

Lymphoepithelioma-like carcinoma of the skin (LELCS) is a rare primary skin cancer, with an annual incidence of 1/100,000 and about 85 cases published in the literature. It is considered the cutaneous counterpart of undifferentiated nasopharyngeal carcinoma (UNC, Schmincke-Regaud tumor) but has no association with EBV. We present an interesting case with features of LELCS in a 93-year-old man, right frontal-orbital region, diagnosed histologically and with immunohistochemical features. We also emphasize contrasting morphologic features for correct nosographic classification and address current issues, suggesting potential insights. Finally, we briefly reviewed other cases described in the literature.

Lymphoepithelioma-like carcinoma of head and neck skin: a systematic analysis of 11 cases and review of literature

Lymphoepithelioma-like carcinoma of the skin (LELCS) is a rare tumor of unknown etiology, low malignant potential, and microscopic resemblance to undifferentiated nasopharyngeal carcinoma. Clinically, it presents as a flesh-colored firm nodule or plaque on the face, scalp, or shoulder of middle-aged to elderly individuals. Histologically, LELCS is composed of islands of enlarged epithelial cells with large vesicular nuclei surrounded and permeated by a dense lymphoplasmacytic infiltrate. LELCS exhibits immunoreactivity with high-molecular-weight cytokeratins and epithelial membrane antigen, indicating the epithelial origin. The differential diagnosis includes basal cell carcinoma, squamous cell carcinoma, lymphoma, pseudolymphoma, and Merkel cell carcinoma. We report 11 cases of LELCS of the head and neck region with discussion of the clinical, histopathologic, immunohistochemical, and therapeutic aspects of this rare cutaneous neoplasm. In addition, we systematically review and compare the findings with the previously published cases of LELCS. This study is the largest case series of LELCS reported in the English-language literature. It attempts to more clearly define the diagnostic criteria for LELCS. Its histomorphologic and immunophenotypic features help distinguish this tumor from similar-appearing malignancies, including metastatic nasopharyngeal carcinoma.

A case of lymphoepithelioma-like carcinoma of the skin associated with Epstein-Barr virus infection

Lymphoepithelioma-like carcinoma of the skin (LELCS) is a rare cutaneous neoplasm with histopathologic similarities to nasopharyngeal carcinoma. The association of nasopharyngeal carcinoma with Epstein-Barr virus (EBV) is well documented. EBV has also been reported to be associated with LELC in only four sites (the stomach, salivary glands, lung, and thymus), but not in the skin. We report herein a case of EBV-positive LELCS. An 82-year-old female presented with a red nodule on the right cheek. Histologically, the entire dermis was occupied by atypical tumor cell nests with dense lymphocytic infiltration. Neoplastic cells were strongly positive for cytokeratin 14 but were negative for cytokeratins 19 and 20. EBV genomes in neoplastic cells were detected by polymerase chain reaction analysis and in situ hybridization for EBV-encoded RNA, suggesting an association with EBV.

Spiradenocarcinoma Arising from a Spiradenocylindroma: Unusual Case with Lymphoepithelioma-Like Areas

Background:

Hybrid skin adnexal tumors are common, and spiradenocylindroma is well described.

Objective:

However, malignant transformation in this setting is infrequent, especially resemblance to lymphoepithelioma-like carcinoma of skin, which is not associated with Epstein-Barr virus.

Methods:

A 65-year-old female presented with ataxia and a skin nodule composed of a hybrid adnexal tumor (spiradenoma and cylindroma) that transitioned into an undifferentiated carcinoma with attendant lymphocytes and plasma cells. There was widespread dissemination of the undifferentiated component to regional neck lymph nodes.

Results:

The undifferentiated component resembled a lymphoepithelioma-like carcinoma and showed focal evidence of tubular and squamous differentiation. The tumor was Epstein-Barr encoded RNAs (EBER) negative by in situ hybridization. No evidence of neuroendocrine differentiation was seen in the tumor, despite the patient having symptoms of paraneoplastic ataxia that improved after surgery.

Conclusion:

This case highlights the transition of a benign hybrid tumor (spiradenocylindroma) into a spiradenocarcinoma that resembled lymphoepithelioma-like carcinoma of skin. It also highlights two unusual features: widespread lymph node dissemination and presentation with paraneoplastic syndrome-associated ataxia.

Lymphoepithelioma-like carcinoma of the skin

The term lymphoepithelioma-like carcinoma identifies a group of nasopharingeal epithelial tumors characterized by aggregates of malignant undifferentiated cells surrounded by a dense reactive lymphoplasmacellular infiltrate. Primary cutaneous localization is rare, with approximately 30 cases reported in literature. We describe a case of primary lymphoepithelioma-like carcinoma of the skin in a 92-year-old woman. Immunohistochemical examination was positive for cytokeratine (KL1 and EMA) as regards epithelial cells, while the lymphocitic infiltrate was positive for LCA and CD3. In situ hybridization for Epstein Barr virus in tumor cells was negative. Electron microscopy showed rounded and occasionally spindle-shaped poorly-differentiated squamous epithelial cells, and a lymphoid stroma consisting mostly of normal-appearing small lymphocytes. Examination of the nasopharynx did not show any tumoral mass and after a 7 years follow-up the patient is free of local and distant recurrences. This tumor affects people aged over 50 years and is localized to the face, but scalp, shoulder and forearm may be involved. Research of Epstein-Barr virus is always negative in this tumor, unlike nasopharingeal epithelial carcinoma. The differential diagnosis of lymphoepithelioma-like carcinoma of the skin may present some difficulties and includes squamous cell carcinoma. Lymphoepithelioma-like carcinoma of the skin is a malignant neoplasm which tends to relapse locally and has a moderate tendency to metastatize.

Lymphoepithelioma-like carcinoma arising in the scar from a previously excised basal cell carcinoma

We report a case of a primary lymphoepithelioma-like carcinoma of the skin (LELCS) associated with scar from a previous excision of basal cell carcinoma. The patient was a 68-year-old female with a 3.0 mm skin-colored pearly papule on her forehead that developed over 2-3 months. The patient had a history of a basal cell carcinoma in the same location, which was completely excised 1 year earlier. A biopsy and subsequent excision of the tumor were performed. The tumor consisted of small islands of large pleomorphic mitotically active epithelioid cells surrounded by a very dense lymphoplasmacytic infiltrate. The tumor was associated with dermal scar. There was no connection of tumor with the unremarkable epidermis. Immunohistochemical examination showed that the epithelioid tumor cells were positive for pan-cytokeratin and epithelial membrane antigen, supporting the morphologic impression of LELCS. The lesion was negative for Epstein-Barr virus. Retrospective review of the original excision specimen confirmed the diagnosis of an ordinary basal cell carcinoma. Forty-five cases of LELCS have been reported to date. We report the first case of LELCS to arise in the scar from an excision of a cutaneous malignancy.