Detection of Epstein-Barr virus only in lymphoepithelial carcinomas among primary carcinomas of the lung

Amyloid and hyaline globules in undifferentiated nasopharyngeal carcinoma

We characterize the clinicopathological features of two patients (one 38 year old woman and one 42 year old man, both of Chinese ethnicity) with Epstein Barr Virus positive non-keratinizing nasopharyngeal carcinoma from an endemic region with prominent presence of amyloid and one case with both amyloid and abundant intracytoplasmic hyaline globules. The amyloid material was positive for Congo red and showed apple green birefringence when examined under polarized light. The amyloid was immunoreactive for cytokeratins and was located both intra- and extracellularly. Frequently the amyloid had a light microscopical spherical appearance and displayed peripheral radiating fibrils from a central homogenous core. One of the patients had a unique presentation of nasopharyngeal carcinoma with perceived hemoptysis and coughing up two pieces of tumor tissue. In reality, the nasopharyngeal tumor was polypoid and the two fragments were pinched of from the main tumor mass.

Herpes and polyoma family viruses in thyroid cancer

Thyroid cancer is considered the most common malignancy that affects the endocrine system. Generally, thyroid cancer derives from follicular epithelial cells, and thyroid cancer is divided into well-differentiated papillary (80% of cases) and follicular (15% of cases) carcinoma. Follicular thyroid cancer is further divided into the conventional and oncocytic (Hürthle cell) type, poorly differentiated carcinoma and anaplastic carcinoma. Both poorly differentiated and anaplastic carcinoma can arise either de novo, or secondarily from papillary and follicular thyroid cancer. The incidence of thyroid cancer has significantly increased for both males and females of all ages, particularly for females between 55–64 years of age, from 1999 through 2008. The increased rates refer to tumors of all stages, though they were mostly noted in localized disease. Recently, viruses have been implicated in the direct regulation of epithelial-mesenchymal transition (EMT) and the development of metastases. More specifically, Epstein-Barr virus (EBV) proteins may potentially lead to the development of metastasis through the regulation of the metastasis suppressor, Nm23, and the control of Twist expression. The significant enhancement of the metastatic potential, through the induction of angiogenesis and changes to the tumor microenvironment, subsequent to viral infection, has been documented, while EMT also contributes to cancer cell permissiveness to viruses. A number of viruses have been identified to be associated with carcinogenesis, and these include lymphotropic herpesviruses, namely EBV and Kaposi's sarcoma-associated herpesvirus [KSHV, also known as human herpesvirus type 8 (HHV8)]; two hepatitis viruses, hepatitis B virus (HBV) and hepatitis C virus (HCV); human papillomaviruses (HPVs); human T cell lymphoma virus (HTLV); and a new polyomavirus, Merkel cell polyomavirus identified in 2008. In this review, we examined the association between thyroid cancer and two oncogenic virus families, the herpes and polyoma family viruses, and we discuss their potential role as causative agents in thyroid carcinogenesis.

Epstein-Barr virus-associated lymphoepithelial carcinoma in the pancreas

Lymphoepithelial carcinoma is a relatively common malignancy in the nasopharyngeal region, but it rarely occurs at other sites. We report a lymphoepithelial carcinoma in the pancreas of a 65-year-old male patient operated on for a gastric stump carcinoma 7 years previously. The solitary tumor in the pancreas presented as a circumscribed lesion and measured 5.5 cm in diameter. The tumor was densely infiltrated by lymphocytes, and the neoplastic cells fulfilled all criteria for a lymphoepithelial carcinoma. Several peripancreatic lymph node metastases were observed. Marked reactivity for Epstein-Barr virus (EBV) early RNA (EBER) was detected in the majority of tumor cells using in situ hybridization. Nuclear EBER signals were also detected in the previously operated gastric stump adenocarcinoma, which also exhibited focal lymphocytic infiltration but otherwise displayed a histology different from lymphoepithelial carcinoma and did not show local recurrence. Even though an unusually late metastasis of the gastric carcinoma cannot be ruled out, we favor the hypothesis that this patient developed an EBV-related pancreatic lymphoepithelial carcinoma as a second primary tumor, based on the considerable delay of this tumor manifestation, the unusual site, the pathologic presentation, the exclusively peripancreatic nodal spread, and the different histology of the lesion.

Epstein-Barr virus involvement is mainly restricted to lymphoepithelial type of gastric carcinoma among various epithelial neoplasms

To demonstrate the association of Epstein-Barr virus (EBV) with primary epithelial neoplasms in the south part of Kyushu, Japan, 761 carcinomas consisting of 75 lung, 61 breast, 107 esophagus, 102 colon, 58 pancreas, 45 thyroid, and 313 gastric cancers were examined by EBER-1 in situ hybridization. EBER-1 was detected in 23 cases (7.3%) out of 313 gastric carcinomas, while none of the other carcinomas was positive for EBER-1. Twenty-eight (9.4%) out of 313 gastric carcinomas were differentiated poorly to moderately carcinomas with prominent lymphoid cell infiltration, similar to so-called lymphoepithelioma-like carcinoma, and 19 cases (67.9%) were positive for EBER-1. Although two (2.6%) and 11(10.3%) out of 75 lung and 107 esophagus carcinomas were so-called lymphoepithelioma-like carcinomas, respectively, but EBER-1 was not detected in other epithelial neoplasms that originated from the lung, esophagus, breast, colon, pancreas, and thyroid in the south of Kyushu, Japan. As a result, EBV was associated with only some gastric carcinomas but not with other epithelial neoplasms originating from the lung, esophagus, breast, colon, pancreas, and thyroid in southern Japan.

Histologic subtyping and malignancy assessment of cutaneous squamous cell carcinoma

BACKGROUND

Squamous cell carcinomas (SCCs) of the skin have a wide range of histologic subtypes and there are indications of differences in prognosis.

OBJECTIVE

The morphologic variety of SCCs with respect to its biological behavior and the further course of disease is analyzed, with emphasis on histopathologic criteria, briefly quoting the main clinical and pathogenetic aspects.

METHODS

Referring to the international tumor classification of the World Health Organization, histologically different carcinoma variants are presented and discussed, based on a review of the literature regarding each subtype, and also including the desmoplastic SCC type.

RESULTS

Histologically, common invasive SCCs are most frequently found, while metastases mainly occur in tumors of high thickness and poor differentiation. The immature spindle cell carcinoma type resembles sarcoma and may grow rapidly with an aggressive clinical course. Lymphoepithelioma-like carcinoma of the skin is extremely rare and its histogenesis remains to be elucidated. Thus far, one case with metastasis and lethal outcome has been reported. As details determining the progression ability have so far only been scanty and partially contradictory, more investigations are necessary, especially for acantholytic SCCs and invasive SCCs developing from Bowen's disease, whereas verrucous carcinomas can be categorized as low malignancy neoplasms. Desmoplastic SCCs, especially with large tumor thickness, should be separated from other SCC subtypes due to their high risk of local recurrence and metastatic spread.

CONCLUSION

The future outcome of SCCs of the skin is significantly influenced by their histologic grade and tumor thickness. In addition, subtyping represents another valuable histopathologic tool for improving the assessment of malignancy.

Tissue distribution of Epstein-Barr virus genotypes

The genome of naturally occurring Epstein-Barr virus contains either two or three copies of a 29-bp tandem repeat sequence in the first intron of the BZLF gene. These genotypes differ markedly in their distribution between blood and epithelial tissues, presumably because they have adapted to separate life cycles in these sites. The genotype prevalent in the blood also appears to be better able to transform B lymphocytes.