GRANULOCYTIC SARCOMA - REPORT OF 5 CASES

Granulocytic sarcoma (GS) is a solid tumor of extramedullary localizat ion constituted by immature precursors from the granulocytic series. G S may be diagnosed in different malignant blood diseases involving the granulocytic series, acute non lymphoblastic leukemia (ANLL) being th e most frequent, followed by myelodysplastic syndromes (MDS) and chron ic myeloproliferative syndromes, specially chronic myeloid leukemia (C ML) in blastic crisis, Although the diagnosis of GS is suspected with conventional cytologic and anatomopathologic studies, histochemical st aining and immunohistochemical techniques are often required for defin itive diagnosis. Five cases (4 males, 1 female; age range 22-77 years) diagnosed with GS in one center over a period of nine years (1984-199 3) are described, The GS were located in the lymph nodes, the jaw, par avertebral region, gallbladder and retroperitoneum, respectively. Two patients had refractory anemia with excess of blasts (RAEB), Three pat ients had ANLL; in one GS constituted the form of relapse, in another GS presented at the time of diagnosis and in the remaining patient GS preceded the diagnosis of ANLL All the patients died from 2 to 8 month s after diagnosis of GS with no response to treatment being observed. Immunohistochemical study of the tumor was performed in 4 patients, be ing positive for lysozyme and the monocytic MAC-387 monoclonal antibod y. Immunocythochemical study of the tumor blasts was carried out with positivity for CD15 being observed.Although uncommon, GS should be sus pected in patients with ANLL or MDS whit tumors of any localization an d at any time during its evolution, Immunocytochemical and immunohisto chemical studies are of great value to differentiate GS from other tum ors, particularly anaplastic non Hodgkin's lymphomas.