Gastric lymphoma causing granulocytopenia and cold intolerance, with recovery after treatment. A 34-year-old man was found to have granulocytopenia with a white blood count of 2.3 x 10(9) l-1, consisting of 10% segmented neutrophils, 50% monocytes and 40% lymphocytes. A bone marrow aspirate showed 20% promyelocytes and 10% blasts with monoblastic features, and a smouldering myelomonocytic leukaemia was considered to be a possible diagnosis. In cold weather the patient experienced cold intolerance with acrocyanosis and small ulcerations on the ears. The test for heparin-precipitable protein ('cryofibrinogen') was strongly positive. During the following year, these signs and symptoms persisted, and the patient also developed constant moderate pain in the epigastric region. Gastroscopy revealed a large lymphoma of the stomach, which was a high-grade malignant centroblastic type of non-Hodgkin's lymphoma. After successful removal of the tumour, and six courses of potent cytostatic combinations, the patient recovered completely, and the granulocytopenia and cold intolerance disappeared. 