21 August 2026
: Case report 
Histiocytic Sarcoma With Striking Clinical Improvement
Challenging differential diagnosis, Unusual or unexpected effect of treatment, Rare disease
Nur Farhanah
EF 1*, Jessica Novia Hadiyanto F 2, Erlieza Roosdhania F 3, Dhesi Ariembi B 4, Enny Puji Astuti B 5, Subiyakto Bustomi F 6, Eny Dyah Kurniawati F 7, Hermawan Istiadi F 8, Budi Setiawan F 9
DOI: 10.12659/AJCR.952214
Am J Case Rep 2026; 27:e952214
Figure 4 Immunohistochemical profile of the lesion; (A) CD163 showing positive cytoplasmic staining in tumor cells; (B) lysozyme showing positive staining, supporting histiocytic differentiation; (C) CD1a showing negative staining; (D) langerin (CD207) showing negative staining. The positivity of CD163 and lysozyme, together with the absence of CD1a and langerin expression, supports the diagnosis of histiocytic sarcoma and excludes Langerhans cell histiocytosis.