Template-Type: ReDIF-Article 1.0 Title: The evanescent tumor, a real diagnostic challenge, in relation to a case Author-Name: Román-Rodríguez, Alejandro Author-Name: Silva-Lago, Rosymar Author-Name: Gallegos Sanchez, José Alfredo Author-Name: Silva-Ramos, Lázaro Author-Name: Díaz Hernández, Pablo Abstract: Introduction: Phantom tumor or evanescent tumor refers to an interlobar pleural effusion that occurs in patients with decompensated heart failure and resembles a lung tumor or mass that disappears after appropriate treatment. Its frequency is unknown.Objective: This entity was described based on a case report, emphasizing the proper use of the clinical method.Case report: The case of a 74-year-old male patient with a past medical history of hypertension and ischemic heart disease is presented. He presented with paroxysmal nocturnal dyspnea, orthopnea, pinpoint pain in the side extending to the right costal margin, fever of 38°C, crackles toward the lung bases, painful hepatomegaly, and edema in both lower limbs. The diagnosis of this presentation, the evanescent tumor or phantom tumor, is achieved through correct use of the clinical method supported by serial chest radiographs and is confirmed by the resolution of the effusion after initiating diuretic treatment.Conclusions: The relevance of this case lies in describing the difficulty of diagnosis, despite the potential complications of a late diagnosis, and demonstrating the need for accurate and effective application of the method. Journal: SAP Health and Policy Year: 2026 DOI: 10.56294/shp2026378 File-URL: https://southam.pub/journals/files/shp/shp2026378en.pdf File-Format: application/pdf Handle: RePEc:cwf:shpart:shp2026378