Abstract
Salivary lymphoepithelial carcinoma is a highly radiosensitive tumor that suggests the effectiveness of induction chemotherapy and induction concurrent chemoradiotherapy without previous surgery. However, the imperfection of diagnostic methods and the severe consequences of misdiagnosis of the tumor do not allow to resign from surgical treatment in patients with this type of salivary gland tumor.
Keywords
We read with interest the manuscript of Lv et al entitled “Is surgery an inevitable treatment for advanced salivary lymphoepithelial carcinoma? Three Case Reports.” 1 The authors’ conclusion based on 3 cases of salivary lymphoepithelial carcinoma. They suggested that induction chemotherapy and induction-concurrent chemoradiotherapy without surgery have the potential to be widely recommended for advanced patients in the future. We find out that the authors’ conclusion is interesting. However, we would like to pay attention to some aspects relating to the diagnostic and treatment of parotid tumors, especially regarding lymphoepithelial carcinoma.
According to Lv et al, in all cases, the tumor was diagnosed after analyzing the results of fine needle aspiration biopsy, MRI, Epstein-Barr virus (EBV) examination, and clinical signs. The authors’ conclusion based on the assumption that tumor diagnosis is precise, which in the case of lymphoepithelial carcinoma is practically impossible.
We just want to remind you that medical history, patients’ complaints, unilateral episodes, slow-growing painless well-defined mass in the parotid area, facial nerve function, enlarged cervical lymph nodes, perineural invasion, and lymphovascular invasion are not specific for salivary lymphoepithelial carcinoma. That salivary lymphoepithelial carcinoma is a rare malignant tumor. It characterized by an undifferentiated nonkeratinizing squamous cell carcinoma with significant lymphocytic infiltration. Cases of this neoplasm accounted for 0.4% of salivary gland tumor. 2 Fine needle aspiration biopsy is a gold standard in the diagnostic of salivary gland tumors. However, according to the literature, fine needle aspiration biopsy showed a sensitivity and a specificity 41.7% to 92.8% and 93.9% to 98.5%, respectively. The accuracy rates varying from 79% to 97% for salivary gland tumors. For pathologically proven malignant tumors, the fine needle aspiration biopsy diagnosis was benign or nondiagnostic in 26% of the cases.3–5 Kim et al reported 3 cases of salivary lymphoepithelial carcinoma when fine needle aspiration biopsy performed, and the histopathological report showed metastatic squamous cell carcinoma. 6 Everything discussed above indicates that the final diagnosis can only make after histological examination of the specimen after surgery.
The lymphoepithelial carcinoma is a well-recognized undifferentiated carcinoma subtype, which quite often related to EBV infection, and all analyzed cases in Lv et al paper were positive for EBV-encoded small RNAs. 1 Nonetheless, in several publications, the authors did not show evidence of EBV infection.7–10 It suggested that EBV-positive test is not obligatory for lymphoepithelial carcinoma.
Imaging findings in CT and MRI are nonspecific, making it difficult to definitively differentiate from other benign and malignant tumors of the salivary glands.11,12
In conclusion, salivary lymphoepithelial carcinoma is a highly radiosensitive tumor that suggests the effectiveness of induction chemotherapy and induction-concurrent chemoradiotherapy without previous surgery. However, the imperfection of diagnostic methods and the severe consequences of misdiagnosis of the tumor do not allow to resign from surgical treatment in patients with this type of salivary gland tumor.
