PO109 | A RARE CASE OF ANEMIA AND THROMBOCYTOPENIA

E. Cosi, A. Bertomoro, I. Bertozzi, G. Bogoni, M. Zerbinati, A. Galbiati, G. Antonello, D. Lovison, P. Simioni | Department of Medicine, University of Padua, Italy

Background. Fibroblastic reticular cell tumor (FRCT) is an extremly rare neoplasm arising from stromal cells of lymphoid tissues, characterized by aggressive biological behavior and significant diagnostic challenges. Due to its rarity, the current literature is limited to a small number of case reports, underscoring the heterogeneity of its clinical and pathological presentation and the absence of standardized diagnostic and therapeutic approaches.
Case Presentation. We describe the case of a 59-year-old woman followed at our hematology Department for heterozygous sickle cell trait, with a past medical history notable only for hysterectomy. Since 2021, she had developed iron-deficiency anemia associated with mild thrombocytopenia and splenomegaly, requiring repeated blood transfusions and parenteral iron supplementation. In 2023, both EGDS and Colonoscopy were unremarkable. In January 2026, the patient was hospitalized due to worsening anemia. She reported a weight loss of 10kg in the last two years and persistent pain in the left abdominal quadrants, without fever or overt bleeding. Laboratory exams revealed normocytic anemia (Hb 61 g/L) with moderate thrombocytopenia (Pts count 61×10⁹/L), normal hemolysis parameters, mild prolongation of coagulation times (PT ratio 1.50, aPTT 1.39), elevated D-dimer levels (1670 µg/L), and increased inflammatory markers (CRP 159 mg/L). A slight increase in AFP was noted, while other tumor markers were negative. Imaging studies demonstrated marked heterogeneous splenomegaly (>18 cm) with a polylobulated lesion of approximately 12 cm, along with suspicious hepatic lesions. PET-CT revealed intense, heterogeneous splenic hypermetabolism with a central hypoactive area and focal hepatic uptake. Bone marrow examination showed hypercellularity with dyserythropoiesis and dysmegakaryocytopoiesis, without evidence of neoplastic infiltration. Liver biopsy identified a high-grade malignant neoplasm positive for cytokeratin MNF116, initially suggestive of undifferentiated sarcomatoid carcinoma. However, the differential diagnosis included accessory cell tumors such as FRCT, particularly given the radiological suspicion of a primary splenic lesion. As these entities differ significantly in prognosis and treatment, and splenic biopsy was contraindicated due to bleeding risk, the patient underwent splenectomy with concurrent thermal ablation of a hepatic lesion. Histological analysis of the spleen revealed a proliferation of spindle and pleomorphic cells with extensive necrosis, immunophenotypically positive for cytokeratin MNF116, consistent with high-grade FRCT. Postoperatively, marked thrombocytosis was observed, followed by stabilization of hematological parameters. One month later, contrast-enhanced CT showed no evidence of disease recurrence. The patient is currently awaiting oncological evaluation for adjuvant chemotherapy.
Conclusions. This case highlights the diagnostic challenges of FRCT, which may mimic undifferentiated carcinoma or sarcoma, particularly in the presence of cytokeratin expression. Accurate diagnosis requires a multidisciplinary approach integrating imaging, histopathology, and immunophenotyping. FRCT should be considered in the differential diagnosis of high-grade splenic tumors, especially when atypical epithelial markers are detected. Splenectomy remains crucial for definitive diagnosis. Further studies are needed to establish optimal management strategies given the rarity of this entity.