Primary cutaneous natural killer/T-cell lymphoma of the nasal type: a report of 4 cases in North American patients

Clinicopathological and prognostic study of primary cutaneous extranodal natural killer/T-cell lymphoma, nasal type: A systematic review

Comprehensive studies of primary cutaneous extranodal natural killer/T-cell lymphoma (PCENKTL) are scarce. The objectives of this study are to describe PCENKTL in terms of its clinical features, histopathology, immunophenotypes, and prognosis, and to analyze factors affecting patient survival outcomes. We searched four databases and include studies with extractable data. We also searched the Asan Medical Center database for cases of PCENKTL. We include a total of 289 patients. The mean age at diagnosis was 52.8 years and the female to male ratio was 1:1.2. The most common clinical morphology was a subcutaneous nodule, followed by ulceration. About half of the patients presented with disseminated skin lesions. The median overall survival was 12.0 months and the 5-year survival rate was 22.0%. There was no correlation between the clinical morphology or the histopathological features of the skin lesions with the patient outcomes. Advanced TNM stage, a disseminated skin lesion, tumor location on the leg or trunk, the presence of B symptoms, and a high International Prognostic Index score were associated with a worse prognosis, and chemoradiotherapy was associated with a better survival outcome as compared with chemotherapy alone in univariable analyses. In multivariable analyses, only advanced TNM stage and tumor location on the leg were associated with a worse prognosis. In conclusion, PCENKTL is an aggressive cutaneous lymphoma and its prognosis is associated with TNM stage and tumor location.

MEG3 affects the progression and chemoresistance of T-cell lymphoblastic lymphoma by suppressing epithelial-mesenchymal transition via the PI3K/mTOR pathway

Long noncoding RNAs (lncRNA) are emerging as integral functional and regulatory components in the development of different diseases including cancer. Maternally expressed gene 3 (MEG3), is a lncRNA, that has a depressed expression in multiple tumor types, including T-cell lymphoblastic lymphoma (T-LBL). However, the molecular mechanisms that regulate the tumorigenic functions of MEG3 in T-LBL remain largely unknown. In this study, we aimed to discover and identify the function of MEG3 in T-LBL tumorigenesis, epithelial-mesenchymal transition (EMT) and drug resistance, and explore their mechanisms of action. Knockdown MEG3 promoted the proliferation, migration, invasion, and drug resistance of T-LBL cells while overexpression of MEG3 gets the opposite results. The mechanism study showed that decreased MEG3 expression in T-LBL cells could activate PI3K/mTOR signaling pathways, increase the expression of p-glycoprotein and affect the expression of EMT markers for transforming to mesenchymal cells in vitro and in vivo. Together, these results indicate that MEG3 could inhibit the migration, invasion, and drug resistance in T-LBL cells by suppression of the PI3K/mTOR pathway. MEG3 might be a potential target, through which poor prognosis with high recurrence and drug resistance of T-LBL in a clinical setting could be reversed.

Angiocentric Centrofacial Lymphoma as a Challenging Diagnosis in an Elderly Man

BACKGROUND Angiocentric centrofacial lymphomas, now known as nasal-type extranodal natural killer T-cell lymphomas, are neoplasms of highly destructive characteristics that mainly affect the nasal cavity and palate. The most frequent clinical presentation includes fever, weight loss, nasal obstruction, epistaxis, nasal or facial edema, as well as necrotic ulcers in the nasal cavity, gums, and palate. It has been found to have an important association with the Epstein-Barr virus. Diagnostic pathology could be difficult due to the typical widespread tissue necrosis. CASE REPORT A 72-year-old Caucasian male sought medical attention with a chief complaint of nasal obstruction for the past 3 years, which only responded partially to unspecific treatment. He also presented with intermittent fever and nocturnal hyperhidrosis. Physical examination with rhinoscopy demonstrated a deviated septum, congestive turbines, and fragile and pale mucous membrane with yellowish, thick mucus. The pathology report described an angiocentric centrofacial lymphoma and a positive serology for Epstein-Barr virus. CONCLUSIONS The objective of this case report was to show that this illness represents a diagnostic challenge for the treating physician. It may be concluded that despite the poor prognosis of the disease, this particular case showed slower evolution and the patient remained stable despite multiple consecutive complications.