Background: Choriocarcinoma is an aggressive trophoblastic malignancy characterized by rapid progression and a strong tendency for early hematogenous metastasis. It may occur in gestational or nongestational forms. Nongestational choriocarcinoma is extremely rare and is most commonly reported in young women. The tumor frequently metastasizes early to organs such as the lungs, liver, and brain. Case presentation: We report the case of a 21-year-old woman who presented with dyspnea and hemoptysis and was initially treated for pneumonia. Further evaluation revealed nongestational choriocarcinoma with pulmonary and hepatic metastases. Diagnosis: Contrast-enhanced computed tomography of the chest initially suggested pulmonary artery thromboembolism; however, the diagnosis was ultimately confirmed by histopathological examination. Conclusion The distinctive feature of this case is that the disease presented with clinical and radiological findings mimicking pulmonary artery thromboembolism. This case highlights the importance of considering metastatic choriocarcinoma in young women presenting with unexplained respiratory symptoms, hemoptysis, and atypical pulmonary vascular findings.

Background: Diffuse large B-cell lymphoma (DLBCL) is a common subtype of non-Hodgkin lymphoma of B-lymphocyte origin, characterized by an aggressive clinical course. Clinically, it most often presents with lymphadenopathy and “B symptoms,” including fever, night sweats, and weight loss. However, in some cases, the disease predominantly involves extranodal organs, such as the spleen, and may present with nonspecific manifestations, thereby posing a diagnostic challenge. Case presentation: A 36-year-old male patient presented with high-grade fever of unknown origin, dyspnea, generalized weakness, sweating, and a 7–8 kg weight loss over one month. Clinical evaluation and laboratory investigations revealed massive splenomegaly measuring 15 × 20 × 20 cm, progressive thrombocytopenia, anemia, and elevated C-reactive protein and lactate dehydrogenase levels. Diagnostic workup for infection, tuberculosis, viral infection, and autoimmune disease did not reveal findings sufficient to establish an alternative diagnosis. Because focal splenic lesions and suspected splenic infarction were identified, splenectomy was performed. Histopathological and immunohistochemical examination of the splenic tissue demonstrated CD20+, CD79a+, BCL2+, CD3−, CD8−, CD30−, and ALK− expression, confirming the final diagnosis of diffuse large B-cell lymphoma. Although DLBCL itself is a common form of non-Hodgkin lymphoma, this case is clinically rare and diagnostically challenging because it presented with predominant splenic involvement, massive splenomegaly measuring 15×20×20 cm, treatment-resistant fever, progressive thrombocytopenia, and imaging findings mimicking splenic infarction. Conclusion In patients presenting with fever of unknown origin that is resistant to treatment, massive splenomegaly, thrombocytopenia, elevated LDH, and increased inflammatory markers, lymphoproliferative disorders should be considered early in the differential diagnosis in addition to infectious causes. Histopathological and immunohistochemical examination play a crucial role in confirming the diagnosis.