en Oncology Oncology case report case report <p><span style="font-size:14px"><span style="font-family:Times New Roman"><strong><em><span style="color:blue">Background:</span></em></strong> Leptomeningeal carcinomatosis involves the diffuse infiltration of neoplastic cells in the central nervous system, affecting 5-8% of leukemia, breast, and lung cancer cases. Gastric cancer instances are rare, mostly in poorly differentiated adenocarcinomas. We report the first Peruvian case, featuring gastric adenocarcinoma.<br> <strong><em><span style="color:blue">Case Presentation:</span></em></strong> A 51-year-old woman presented with severe headache, vomiting, dizziness, blurred vision, tinnitus, bradyphrenia, reduced verbal fluency, sixth cranial nerve paresis, and non-reactive anisocoric pupils. Pleocytosis was found, with positive cytology for metastatic adenocarcinoma in cerebrospinal fluid, and a solid gastric mass defined as poorly differentiated adenocarcinoma. Due to her condition, the patient did not receive oncological management, evolving unfavorably and passing away twenty days later.<br> <strong><em><span style="color:blue">Discussion:</span></em></strong> Leptomeningeal carcinomatosis should be considered in patients with advanced cancer and meningeal symptoms. It is more predominant in women, with an average age of 53.84 years. Clinical presentation of leptomeningeal carcinomatosis varies, and diagnosis involves neuroimaging and cerebrospinal fluid cytology. Prognosis is unfavorable, often leading to fatality. Treatment protocols lack standardization, and personalized approaches, including targeted and systemic therapies, are explored for improved outcomes. The exceptional aspect of our case lies in the unique diagnosis of an abdominal tumor following the manifestation of neurological symptoms.<br> <strong><em><span style="color:blue">Conclusion:</span></em></strong><strong> </strong>It is important to suspect this condition among the causes of meningitis, especially in the presence of an underlying malignancy.</span></span><br> &nbsp;</p> Meningeal Carcinomatosis, Meningeal Neoplasms, Cerebrospinal Fluid, Gastric cancer, Neoplasms. 369 374 http://caspjim.com/browse.php?a_code=A-10-1924-4&slc_lang=en&sid=1 Juan Eduardo Quiroz-Aldave jquirozaldave@hotmail.com 100319475328460054884 100319475328460054884 No Division of Medicine, Hospital de Apoyo Chepén. Chepén, Perú María del Carmen Durand-Vásquez mdurandvasquez@hotmail.com 100319475328460054885 100319475328460054885 No Division of Family Medicine, Hospital de Apoyo Chepén. Chepén, Perú Ramiro Herrera Cabezas ramihc_12f@hotmail.com 100319475328460054886 100319475328460054886 No Division of Internal Medicine, Hospital Nacional Guillermo Almenara Irigoyen. Lima, Perú Rossana Jimenez Asto rossjimeneza31@gmail.com 100319475328460054887 100319475328460054887 No School of Medicine “Manuel Huamán Guerrero”, Universidad Ricardo Palma, Lima, Perú Carlos Cerrón Aguilar ccerron@hotmail.com 100319475328460054888 100319475328460054888 No Division of Internal Medicine, Hospital Nacional Guillermo Almenara Irigoyen, Lima, Perú Julia Cristina Coronado-Arroyo juliacristinacoronado@gmail.com 100319475328460054889 100319475328460054889 No Clínica Internacional, Lima, Perú Francisca Zavaleta-Gutiérrez paquitamed@hotmail.com 100319475328460054890 100319475328460054890 No Division of Neonatology, Hospital Belén de Trujillo, Trujillo, Perú Luis Alberto Concepción-Urteaga lconcepcion@unitru.edu.pe 100319475328460054891 100319475328460054891 Yes Division of Internal Medicine, Hospital Regional Docente de Trujillo, Trujillo, Perú Benjamín Alberto Leiva dr.benjaminleiva@gmail.com 100319475328460054892 100319475328460054892 No Division of Surgical Oncology, Hospital Eleazar Guzmán Barrón. Nuevo Chimbote, Perú Marcio José Concepción-Zavaleta mconcepcion@cientifica.edu.pe 100319475328460054893 100319475328460054893 No Universidad Científica del Sur, Lima, Perú