Metastatic Adenocarcinoma to Bone Marrow Presenting as Microangiopathic Hemolytic Anemia – Diagnostic Issues in a Series of Seven Young Adults

Cancer related microangiopathic hemolytic anemia is a rare entity and shares clinical and hematological features with other causes of thrombotic microangiopathy and leads to diagnostic dilemma and treatment delays. This record-based descriptive study, spanning five years, details the clinicopathological features with special emphasis on the peripheral blood findings in unsuspected cases of bone marrow metastasis of unknown primary in young adults. Seven relatively young patients, with an average age of 27 years, presented with unexplained anemia with peripheral blood showing features of microangiopathic hemolytic anemia, thrombocytopenia, and leukoerythroblastic picture. Subsequent bone marrow examination revealed presence of metastatic adenocarcinoma with the primary site being detected in five of the seven patients. This case series highlights these uncommon, but significant, hematological manifestations of metastatic adenocarcinoma in bone marrow in young adults, and the importance of astute observations of peripheral blood smear in detection of an underlying malignancy.