Incidence, Clinical Features, and Outcomes of Langerhans Cell Sarcoma in the United States

Background: Limited knowledge exists on the incidence, treatment patterns, and long-term outcomes of Langerhans cell sarcoma (LCS) in the United States.

Patients and methods: We performed a retrospective study of LCS patients diagnosed between 2001 and 2014 using the Surveillance, Epidemiology, and End Results (SEER) and National Cancer Data Base (NCDB) databases. Incidence was calculated from SEER, and treatment patterns and outcomes were calculated from NCDB.

Results: A total of 25 and 52 cases of LCS were reported to SEER and NCDB, respectively. The overall incidence of the disease was 0.2 per 10,000,000 and did not differ by race (P = .56) or sex (P = .33). The median age at diagnosis was 62 (range, 19-90) years. Of the 52 patients from NCDB, 20 (39%) received chemotherapy as first-line therapy, 24 (46%) received surgery, and 15 (29%) received radiotherapy. The 1-year overall survival (OS) rate was 62%, and the median OS was 19 months. After censoring the patients with bone marrow and reticuloendothelial system involvement, no significant difference in OS was noted between the patients who were managed with or without surgery (P = .75). Postsurgical radiation or chemotherapy were not associated with improvement in median OS (P = .25). Patients who were managed with radiotherapy had a better OS compared to those who received no radiotherapy (P = .03).

Conclusion: This dual-national registry study shows that LCS is extremely rare and has a poor prognosis. Radiotherapy may offer a survival advantage to patients with locoregional disease without bone marrow and reticuloendothelial system involvement.