The aim of this study was to analyze the value of cytology in differentiation between malignant epithelial tumor metastases and hematologic malignancy. The follow-up of ten (10) patients who underwent diagnosis and treatment of two malignant diseases, i.e. carcinoma and hematologic malignancy, was performed in the 2000-2005 period. The median of age of our patients was 72 years (range: 49-79). Cytological examination included epithelial tumors, lymph nodes and bone marrow standard Pappenheim and immunocytochemically stained smears. Carcinoma was initially diagnosed in 40% (4/10) patients and hematologic malignancy in 50% (5/10) patients, while both diseases co-occurred in one patient (1/10). Most of hematologic malignancy cases (4/10) were diagnosed as lymphoma. Multiple myeloma was diagnosed in 3 out of 10 patients (30%). Individual cases of acute myeloblastic leukemia, chronic lymphocytic leukemia, and chronic myeloid leukemia were diagnosed in the remaining three patients. Most carcinomas were breast cancer (8/10), while prostate and thyroid gland cancer were diagnosed each in one patient, respectively.