Thymic lymphoepitheliomalike carcinoma in children: clinicopathologic features and molecular analysis

Thymic Lymphoepithelial Carcinoma in Children: Report of Four Cases and Review of Literature

Background: Thymic lymphoepithelial carcinoma (TLEC) is a rare subtype of thymic carcinoma that primarily affects middle-aged and older adults and is extremely rare in children. We present four cases of TLEC in children and reviewed the pertinent literature to investigate the clinical and pathological characteristics. Case Report: All four patients are male, with an average age of 10 years (range: 9-13 years). Imaging studies consistently showed an anterior mediastinal mass with a diameter of 5-15 cm. Serum EB virus (EBV) antigen was positive in three patients. Three patients were at Masaoka stage IIb and all survived after surgery, while one patient at Masaoka stage IV died nine months after surgery. Discussion: Males are more likely than females to be affected by the TLEC, which mainly affects older kids. Immunohistochemistry and in situ hybridization tests are useful for diagnosis, and the tumor's occurrence is tightly linked to EBV infection.

A Case of Primary Lymphoepithelioma-Like Carcinoma of the Bladder With Review

Lymphoepithelioma-like carcinoma (LELC) was characterized by epithelial neoplastic cells developing in solid or incohesive sheets mixed with a noticeable lymphoid infiltration. Lymphoepithelioma-like carcinoma of the bladder (LELCB), which was first described by Zukerberg, is a rare variant of LELC. Here we reported a new case of LELCB occurring in a 70-year-old woman presenting with hematuria. Computed tomography (CT) and cystoscopy revealed a tumor on the left upper wall of the bladder. A partial cystectomy was finally performed. Pathological and immunohistochemical analysis revealed LELCB. After receiving systemic adjuvant chemotherapy, the patient conducted a 25-month follow-up without experiencing a recurrence.

Thymic Lymphoepithelial Carcinoma Associated with Epstein-Barr Virus: Experiences and Literature Review

Thymic lymphoepithelial carcinoma (TLEC) is a primary thymic carcinoma that accounts for about 14% of all thymic epithelial tumors and is classified into 14 types. The histological morphology is similar to lymphoepithelioma, a type of undifferentiated nasopharyngeal carcinoma. It has been reported that squamous carcinoma accounts for approximately 80% of thymic carcinoma, followed by TLEC, which accounts for 6%. TLEC has been reported to be associated with Epstein-Barr virus (EBV), with EBV infection in TLEC tumor cells first noted by Lyvraz et al. in 1985. Tumors shown to be EBV-positive are classified as TLEC if lymphoplasmacytic infiltration is lacking. However, only about 50% of the cases are positive for EBV, which is lower compared to nasopharyngeal lymphoepithelioma. Instances of EBV infection in other types of thymic epithelial tumor have been reported at lower rates, which suggests that EBV infection may have an important influence on the carcinogenesis of TLEC, though the etiology is unknown. TLEC is a highly malignant tumor with poor prognosis, as affected patients have a median survival time of 22 months, according to 58 cases from the literature, while the 5-year survival rate is 34.4%. Presently, prognosis is not considered to be affected by the presence or absence of EBV positivity.

Challenges in diagnosing ectopic thymus tissue in children

The presentation of a fast-growing cervical mass necessitates prompt attention due to risk of the mass effect on vital structures and requires preferential screening for infections, bleeding and malignancies in an extensive list of differential diagnoses. This case report describes a 4.5-year-old boy with a fast-growing, unilateral lesion in the neck, with clinical features in keeping with malignant characteristics. Surgical excision with pathocytological examination revealed an exceptional diagnosis of haemorrhage in an ectopic cervical thymic cyst. Thymic cysts are a rare cause of unilateral masses in the neck, usually presenting as an asymptomatic, painless, slow-growing or stable mass anywhere along the thymopharyngeal duct. Spontaneous haemorrhages in thymic tissue can occur, often due to coagulation defects. Treatment of symptomatic thymic cysts is based on surgical excision. Partial resection of the thymus should be encouraged if possible, since clinical consequences of removing all thymic tissue in children are still unclear.

Clinical outcome of thymic lymphoepithelioma-like carcinoma: Case report of a 14-year-old male

Thymic carcinoma is a rare type of cancer, which arises from the thymic epithelium and accounts for ~1–4% of anterior mediastinal tumors in the USA. It rarely occurs in children, and is rarer among adults. Thymic lymphoepithelioma-like carcinoma (LELC) is an uncommon subtype of thymic carcinoma in children, however, it is one of the common histological subtypes of thymic carcinoma in adults. In the present study, a 14-year-old male patient presented to the Tokyo Metropolitan Cancer and Infectious diseases Center, Komagome Hospital (Tokoyo, Japan) with chest pain due to a large anterior mediastinal mass. The patient was histologically diagnosed with thymic LELC via a needle biopsy specimen, which was obtained from the primary site and indicated the Epstein-Barr virus infection, whose markers are also associated with oncogenesis. Immunohistochemical analysis demonstrated positive staining for keratin (AE1/AE3), epithelial membrane antigen, and latent membrane protein-1 and negative staining for cluster of differentiation 5. Thus, the patient was diagnosed with metastatic thymic LELC. First-line chemotherapy comprising of a cisplatin- and adriamycin-based chemotherapy regimen achieved a partial response, however, the patient succumbed within 10 months of the initial diagnosis due to rapid disease progression and refractory to subsequent cycles of chemotherapy. Thus, the current study, as well as previously reported cases, demonstrates that pediatric patients with thymic LELC continue to have a poor prognosis.