Impact of surgery, radiation and systemic therapy on the outcomes of patients with dendritic cell and histiocytic sarcomas

Abstract

Background: Neoplasms of histiocytic and dendritic cell origin, including follicular dendritic cell sarcoma (FDCS), histiocytic sarcoma (HS) and interdigitating dendritic cell sarcoma (IDCS), are extremely rare, and data on their natural history and treatment outcomes are sparse. We evaluated the impact of surgery, radiation and systemic therapies on overall survival (OS).

Methods: We conducted a retrospective chart review of patients with FDCS, IDCS and HS treated at Memorial Sloan Kettering Cancer Center between 1995 and 2014.

Results: We identified 31, 15 and 7 patients with FDCS, HS and IDCS, respectively. Median age was 48.7, 42.3 and 58.8years for FDCS, HS and IDCS, respectively. Only a slight disparity in gender distribution existed for FDCS and HS; however, IDCS predominantly affected males (6:1). The most common sites of presentation were abdomen and pelvis (42%), extremities (33%) and head and neck (57%) for FDCS, HS and IDCS, respectively. At diagnosis, 74%, 40% and 86% of patients presented with localised disease in FDCS, HS and IDCS, respectively. Patients with localised disease had significantly improved OS than those with metastatic disease in FDCS (P=0.04) and IDCS (P=0.014) but not in HS (P=0.95). In FDCS and HS, adjuvant or neo-adjuvant therapy was not associated with improved OS compared with observation. In IDCS, surgery alone provided a 5-year overall survival rate of 71%.

Conclusions: Adjuvant or neo-adjuvant treatment in FDCS and HS did not affect OS. Patients with IDCS had an excellent outcome with surgery. In the metastatic setting, chemotherapy and small molecule inhibitors may provide benefit.

Keywords: Adjuvant therapy; Dendritic sarcoma; Histiocytic neoplasm.

Fig. 1

Kaplan–Meier curve of overall survival by histology and stage. The log rank p-value comparing all six curves is <0.001. The log-rank p-value comparing localised and metastatic disease in follicular dendritic cell sarcoma (FDCS), histiocytic sarcoma (HS) and interdigitating dendritic cell sarcoma (IDCS) patients is 0.04, 0.94, and 0.01, respectively.

Fig. 2

Type and duration of benefit of systemic therapies in patients with metastatic or recurrent disease with (A) follicular dendritic cell sarcoma (FDCS) and (B) histiocytic sarcoma (HS) and interdigitating dendritic cell sarcoma (IDCS). RT, radiation; A, doxorubicin; AIM, doxorubicin, ifosfamide and mesna; C, cyclophosphamide; CP, standard CHOP regimen, cyclophosphamide, doxorubicin, vincristine and prednisone; CLD, cladribine; IF, ifosfamide; ICE, ifosfamide, carboplatin and etoposide; GD, gemcitabine and docetaxel; GC, gemcitabine and carboplatin; GI, gemcitabine and irinotecan; VB, vinblastine; VC, vincristine; VAC, vincristine, doxorubicin and cyclophosphamide; † = dead at last follow-up.