Objectives: To analyze the clinical characteristics and prognostic factors in Chinese patients with classical Hodgkin's lymphoma (cHL) involving extranodal sites. Methods: Clinical features and outcomes of 68 patients diagnosed with cHL involving extranodal sites from April 2003 to November 2017 were analyzed retrospectively. The data was compared with that of 76 cHL patients without extranodal involvement in the same period. Results: (1) Extranodal involvement was common in Chinese cHL patients. The most common sites were lung (44.1%) and bone (33.8%), followed by bone marrow, liver, pericardium, pleura and other sites. (2) With a median follow-up period of 4.58 years, the 5-year overall survival (OS) of 68 patients with extranodal involvement was significantly poorer than that of 76 patients with only nodal involvement (81.4% vs. 92.8%, p = 0.018). (3) In univariate analysis, lymphocytopenia (p = 0.027), elevated lactate dehydrogenase (LDH) (p = 0.026) and involved lymph node region (LNR) ≥4 (p = 0.044) predicted inferior freedom from progression (FFP) with significant difference. Elder age (p = 0.010), elevated LDH (p = 0.013), elevated platelet (p = 0.044), involved LNR ≥ 4 (p = 0.047) were also statistically significant in OS. Extranodal sites and number of extranodal sites showed no significant difference in FFP and OS. Factors with p-value smaller than 0.100 were evaluated in multivariate analysis, turning out that lymphocytopenia was the only independent adverse prognostic factor in FFP (p = 0.039; HR = 2.595) and OS (p = 0.028; HR = 4.993). Conclusion: Extranodal involvement was frequent in Chinese cHL patients, with lung to be the most commonly involved site. Lymphocytopenia was the only independent adverse prognostic factor.
Keywords: Chinese; Classical Hodgkin’s lymphoma; clinical characteristics; extranodal involvement; lung; lymphocytopenia; prognosis; survival.