[Thrombotic thrombocytopenic purpura disclosing cancer: apropos of 2 cases]

Thrombotic thrombocytopenic purpura (TTP) causes severe haemolytic anaemia, thrombopenia, fever and neurological and renal involvement. Currently five large aetiologic groups have been identified: viral or bacterial infection, drugs, conjunctive tissue diseases, pregnancy and solid tumours. We observed two cases resulting from an adenocarcinoma. In the first case, a 71-year-old man with chronic silicosis, the presenting signs were asthenia, fever, epistaxis with diffus purpura and spontaneous haematomas of the lower limbs. Diagnosis of TTP was based on routine laboratory tests and the patient responded well to fresh frozen plasma. On the 5th day of treatment, haemoglobin level dropped sharply and melana occurred. Upper digestive tract endoscopy revealed a tumoural formation of the antrum-fundic junction and histology examination of the biopsy confirmed the diagnosis of adenocarcinoma. Ten months after gastrectomy the patient was in excellent health with no relapse of the TTP. In the second case, the presenting signs included spontaneous haematomas, rectorrhagia and low grade fever. Microscopic haematuria and renal failure were observed in addition to the biological syndrome of TTP. The patient responded poorly to fresh frozen plasma and packed cell transfusions. Plasma exchange was equally unsuccessful. The disease continued a fulminant course and the diagnosis of adenocarcinoma located in a pulmonary lymph nodes was made at autopsy. These rare cases of TTP caused by cancer emphasize the importance of a thorough aetiological research. Plasma exchange has been shown to be effective but mortality at 1 year approximately 85% in cancer related cases. Early diagnosis and specific anti-cancer therapy might improve prognosis. We report our personal experience with 16 other similar cases.