Microangiopathic Haemolytic Anaemia and Mucin‐forming Adenocarcinoma

Abstract

Summary. Twelve patients are described who developed well‐marked micro‐angiopathic haemolytic anaemia in association with metastatic carcinoma. The tumours originated in the stomach in six cases, in the breast in two cases, in the lung in one case and the origin was uncertain in three cases. All 11 tumours studied were found to be mucin‐secreting adenocarcinomas.Ten out of the 12 patients were thrombocytopenic. Fibrinogen metabolism was studied in four patients and in each patient the catabolism of fibrinogen was found to be greatly increased despite normal or near normal plasma fibrinogen levels and an absence of overt fibrinolysis. Fibrin degradation products were demonstrated in the serum of five out of six patients. Hyaline thrombi were seen in the small blood vessels in the kidneys and suprarenals in one patient and in the myocardium in two patients, while changes suggestive of organized thrombi were present in the interlobular arteries of the kidneys in three patients.It is thought likely that the microangiopathic haemolytic anaemia develops secondarily to intravascular coagulation brought about by thromboplastins derived from mucin‐forming tumour cells which have entered blood vessels, and that contact between circulating red cells and tumour emboli within blood vessels may be an additional cause of red‐cell damage.