The clinical analysis of pulmonary lymphoepithelioma-like carcinoma with epithelioid granuloma

Background: Pulmonary lymphoepithelioma-like carcinoma (PLELC) is a rare subtype of non-small cell lung cancer associated with Epstein-bar virus (EBV) infection. Epithelioid granuloma (EG) has been more scarcely reported and frequently misdiagnosed. Methods: Data were collected from January 2013 to October 2019. Of 227 patients diagnosed as having PLELC, 22 patients had EG. We analyzed their clinical features, pathological characteristics and treatment and a comparison between PLELC patients complicated with or without EG was made. Results: Twenty-two patients had complicated with EG (9.6%). The median age was 50 years (3867 years). There were more females than males (1.4: 1). Most patients were at early stage (68.2%) with nonspecific manifestations and lack of Rich-Lewis phenomenon. Compared with the 205 patients complicated without EG, there were no significant difference among age (t=0.938, P=0.349), gender (chi(2)=0.898, P=0.343), initial symptoms (chi(2)=2.684, P=0.443), smoking status (chi(2)=0.210, P=0.647), diameter of tumor(t=0.993, P=0.332) and performance status (H=0.971, P=0.615). EG was often located inside or adjacent to the tumor (71.4%). Specific staining was negative, whereas in situ hybridization staining of EBV-encoded RNA was consistently positive. Most patients complicated with EG received multimodality therapy including surgery, neo-adjuvant/adjuvant chemotherapy or palliative chemotherapy and none of them received anti-TB therapy. Compared with the 205 patients complicated without EG, there were no significant difference among tumor stage, DFS (median, not reached, P=0.914), PFS (median, 12.3 months, P=0.848), OS (median, not reached, P=0.737) and treatment including anti-tumor therapy and anti-TB therapy. During follow-up duration for 14.6 months (range, 2.1-94.7 months), none of the patients had occurrence, progression or relapse of tuberculosis, regardless whether anti-tuberculosis therapy was initiated. Conclusions: PLELC complicated with EG was lack of Rich-Lewis phenomenon and specific clinical characteristics compared with those without EG. EG might be caused by immunological hypersensitivity to tumor cells or EBV infection but not pulmonary tuberculosis. PLELC complicated with EG could be treated with chemotherapy and surgery. However, anti-tuberculosis therapy was unnecessary.