Clinicopathological consultation. Lymphoepithelial carcinoma of the larynx hypopharynx, and trachea

Rare Diseases of Larynx, Trachea and Thyroid

This review article covers data on rare diseases of the larynx, the trachea and the thyroid. In particular, congenital malformations, rare manifestations of inflammatory laryngeal disorders, benign and malignant epithelial as well as non-epithelial tumors, laryngeal and tracheal manifestations of general diseases and, finally, thyroid disorders are discussed. The individual chapters contain an overview of the data situation in the literature, the clinical appearance of each disorder, important key points for diagnosis and therapy and a statement on the prognosis of the disease. Finally, the authors indicate on study registers and self-help groups.

Patterns of EBV-positive cervical lymph node involvement in head and neck cancer and implications for the management of nasopharyngeal carcinoma T0 classification

OBJECTIVES

Epstein-Barr virus (EBV)-positive cervical lymph node (CLN) metastasis of unknown primary origin is classified as nasopharyngeal carcinoma (NPC) T0 by the American Joint Committee on Cancer staging manual (8th edition). We aimed to investigate the possible primary sites and patterns of EBV-positive CLN metastases and to provide implications for the management of NPC T0 classification.

MATERIALS AND METHODS

We retrospectively reviewed 269 patients with newly diagnosed EBV-positive CLN metastatic disease who underwent EBV detection via EBV-encoded RNA in situ hybridization. Fifteen patients with unknown primary tumors underwent follow-up after initial treatment.

RESULTS

In patients with EBV-positive CLNs, the most common primary sites after the nasopharynx (51.7%) were the salivary gland (24.5%), lung (7.8%), oropharynx (3.3%), nasal cavity/maxillary (3.3%), oral cavity (2.2%), orbit (1.1%), and liver (0.4%). No primary site was found in 15 patients (5.6%). For salivary gland malignancies, level II and I were the most frequently involved regions. Tumors arising from the lung or liver metastasized to the lower neck (level IV, V, and VI) rather than the upper neck. After initial treatment, 2/15 patients with EBV-positive CLNs of unknown primary exhibited primary NPC and oropharyngeal tumor, respectively. Further, even without prophylactic irradiation to the nasopharynx, only one of 13 unknown primary patients developed NPC.

CONCLUSIONS

The origins of EBV-positive CLNs may not be restricted to the nasopharynx alone, and are likely to involve the head and neck or non-head and neck regions. NPC T0 classification should be cautiously assigned to such tumors.

Role of ancillary techniques in profiling unclassified laryngeal malignancies

Laryngeal biopsies, contrary to biopsies from many other sites of the body, very often contain minute amounts of tumour tissue that may consist of morphologically undifferentiated tumour only. In haematoxylin- and eosin-stained sections, there may be no indicative features of what specific tumour entity that is present. In the larynx, particularly small round cell neoplasms, primary or metastatic, often cause a diagnostic dilemma and where an incorrect diagnosis can induce substantial clinical consequences for the patient (e.g., primary neuroendocrine carcinomas vs metastatic variants, certain sarcomas). If sufficient/representative material has been obtained, the application of immunohistochemistry and/or molecular techniques should in virtually every case reveal the true nature of the malignancy. In cases with sparse amount of material, and therefore a limited number of sections to be cut, a careful and thoughtful stepwise approach is necessary to ascertain a reliable diagnosis, or at least guide the clinician to the most likely diagnoses. With today's advanced and widely available technology with an abundance of markers to discriminate different tumours, the use of the term "undifferentiated" should be largely unnecessary. In the exceptional, and indeed exceedingly rare cases, when a classification is not possible, even after repeat biopsy, we suggest that the laryngeal neoplasm is better termed "unclassified malignant neoplasm" rather than "undifferentiated malignant neoplasm".

Lymphoepithelial carcinoma: a case report of a rare tumor of the larynx

BACKGROUND

Lymphoepithelial carcinoma is a tumor mostly diagnosed in the nasopharynx, but it has also been described in a variety of nonnasopharyngeal sites. It is extremely rare in the larynx and should be distinguished from squamous cell carcinoma. Therefore, it must be known by clinicians, pathologists and oncologists. In this case report, we discuss its etiopathogeny, its epidemiological, clinical, pathological and therapeutic aspects, and its outcome.

CASE PRESENTATION

An 81-year-old Morrocan man, smoker for 40 years, presented with a 1 year history of dysphonia, dyspnea and dysphagia. Laryngoscopy showed a mass occupying supraglottic, glottic and subglottic levels of the larynx. Cervico-thoracic computed tomography scan showed a laryngeal wall thickening with cervical lymphadenopathy. Laryngeal biopsy was performed. Microscopic analysis and immunohistochemistry confirmed the diagnosis of laryngeal lymphoepithelial carcinoma. Immunostaining for LMP1 was negative.

CONCLUSION

Laryngeal lymphoepithelial carcinoma is an extremely rare and an aggressive tumor. It is rarely associated with the EBV. It must be regarded as a distinct entity. Radiotherapy is advisable as the unique therapy for local tumor. A correct diagnosis and a close collaboration between the pathologist and clinicians is mandatory for an optimal treatment strategy.

How phenotype guides management of non-conventional squamous cell carcinomas of the larynx?

Although the majority of laryngeal malignancies are the conventional squamous cell carcinomas (SCC), a wide variety of malignant epithelial tumors can affect the larynx. Current treatment guidelines are designed to guide clinicians in management of conventional laryngeal SCC. Less is known about the biological behavior and responsiveness to therapy and overall outcomes of other malignant epithelial lesions. Because a spectrum of disease biology is represented by these rare phenotypes, an understanding of the basic biology can help direct management to optimize clinical outcome in this group of patients. This review provides a critical analysis of literature relating to the diagnosis, management, and outcome of patients with non-conventional squamous malignant epithelial neoplasms of the larynx. Particular attention is paid to features which are at variance with the conventional SCC and how these impact on management of these rare tumors.

Current diagnostic strategies for undifferentiated tumours of the nasal cavities and paranasal sinuses

Several malignant tumours occurring in the sinonasal tract may present with an undifferentiated morphology. Overall, these lesions pose significant diagnostic difficulties for the surgical pathologist, especially in limited biopsy material, but their correct classification is becoming increasingly important for an appropriate treatment strategy. This review deals with the criteria for differential diagnosis of these neoplasms, with emphasis on recent advances in immunohistochemistry and molecular biology, as well as with previous progress in electron microscopy. Through careful microscopic examination of haematoxylin and eosin-stained sections, in the light of clinical information and imaging data, a list of differential diagnoses can be made and an appropriate panel of antibodies can be chosen to further categorize the tumour. An initial panel including cytokeratins, synaptophysin, S100 protein, desmin and CD45 may allow the classification of most lesions or may help to narrow the list of differential diagnoses. Further refinement can be obtained through second-line markers, including in-situ hybridization for Epstein-Barr virus, other neuroendocrine markers, melanocytic markers, myogenin, CD99, other lymphocyte markers, and CD138 and light chains. Finally, molecular analysis can further assist in the recognition of specific entities such as nuclear protein in testis midline carcinoma, Ewing's sarcoma/peripheral neuroectodermal tumour, alveolar rhadbomyosarcoma, and poorly differentiated synovial sarcoma.

Lymphoepithelial carcinoma of the larynx

Lymphoepithelial carcinoma (LEC) of the larynx is a rare neoplasm; with a review of the literature having disclosed only 34 documented cases. This neoplasm seems to behave in a fashion reminiscent of nasopharyngeal carcinoma. In contrast to nasopharyngeal carcinoma, most cases have not been associated with Epstein-Barr virus (EBV). The diagnosis often requires immunohistochemistry or electron microscopy for confirmation. We describe a case of this tumor involving the supraglottis. The patient was treated with supraglottic laryngectomy and bilateral modified neck dissection. The histopathological study of the surgical specimen revealed an undifferentiated carcinoma with aspects of lymphoeptihelioma. The patient underwent radiotherapy and his 2-year follow-up showed no evidence of local or distant metastasis.

Management of the clinically negative cervical lymph nodes in patients with non-conventional squamous carcinoma of the larynx

This paper discusses the indications for neck dissection in those patients with laryngeal tumours which prove to be, on pathologic examination, not conventional squamous carcinomas but rather fall into the category either of one of the uncommon histological subtypes of carcinoma, or another type of unusual histological variant of laryngeal malignancy, a mesenchymal tumour. It appears as though these unusual laryngeal malignancies may manifest both biological behaviours and propensities to metastasize to regional lymph nodes that differ from those of the more commonly encountered conventional squamous carcinomas of the larynx. This heterogeneous group of tumours accounts for about 10 per cent of all malignant tumours of the larynx.