Barzilai University Medical Center

111 Research Day 2020 Barzilai University Medical Center 78 A RARE CASE OF UNKNOWN PRIMARY WITH FIRST PRESENTATION OF LEPTOMENINGEAL DISSEMINATION: APPROACH AND LITERATURE REVIEW Lottem Bergman 1,2 , Moshe Schaffer 1,3 , Aljandro Livof 3,4 , Noam Asna 1,3 1 Department of Oncology, Barzilai University Medical Center- Ashkelon, Israel. 2 Sackler Medical School, Tel-Aviv University, Israel. 3 Faculty of Health Sciences, Ben Gurion University, Beer Sheva, Israel. 4 Department of Pathology, Barzilai Medical Center- Ashkelon, Israel. Background Leptomeningeal dissemination (LMD) is a major disease complication in primary central nervous system, of solid tumors outside the CNS such as breast, lung, gastrointestinal cancer, melanoma, and as well in hematological malignancies. Hypothesis and objectives We describe a case of a previously healthy 67-year-old man who developed over 1 month a decline in general condition and cognition. He was admitted to the emergency department after recurrent falls. Chest CTA demonstrated lytic lesions in the cervical vertebra. HMO blood tests implied suspect of Multiple myeloma (MM). A head CT reveled periventricular hypotensive area. LP found elevated opening pressure and cytology was positive for malignant cells (adenocarcinoma). We started treatment with high dose dexamethasone daily following single intrathecal methotrexate. Bone marrow biopsy showed poorly differentiated carcinoma. Immunostaining was positive for PAN- KERATIN/MNF-116/CK-20, and negative for CK7/CD20. CA19.9/CEA. MRI revealed hydrocephalus and diffused LMD. Patient developed neutropenia, and then received one dose of paclitaxel with carboplatin, after 3 days patient was found dead. PM was not done. The total clinical course was 2 months, total time of treatment was 17 days. Results Treatment with the dexamethasone gave a good cognitive improvement for a weak. Due to high level of CEA and CA-19-9 and the presence of poorly differentiated Adenocarcinoma, brought us to a conclusion that the probably tumor was a gastric tumor. Literature survey revealed only 14 similar cases, from them only 7 had a suspected primary tumor. Conclusion Early diagnosis of LMD is major key for rapid initiation of chemotherapy and or radiation therapy. This case demonstrates that solid tumors may manifest with LMD even in the absence of systemic disease. In cases where there is a reliable serum tumor marker, cognitive decline in the absence of systemic disease may pressurized investigation for LM.