Serum total tryptase level confirms itself as a more reliable marker of mast cells burden in mast cell leukaemia (aleukaemic variant).

Mast cell leukemia (MCL) is a very rare form of systemic mastocytosis (SM) with a short median survival of 6 months. We describe a case of a 65-year-old woman with aleukaemic variant of MCL with a very high serum total tryptase level of 2255 µg/L at diagnosis, which occurred following an episode of hypotensive shock. She fulfilled the diagnostic criteria of SM, with a bone marrow smear infiltration of 50-60% of atypical mast cells (MCs). She tested negative for the KIT D816V mutation, without any sign of organ damage (no B- or C-findings) and only few mediator-related symptoms. She was treated with antihistamine alone and then with imatinib for the appearance of anemia. She maintained stable tryptase level and a very indolent clinical course for twenty-two months; then, she suddenly progressed to acute MCL with a serum tryptase level up to 12960 µg/L. The patient died due to haemorrhagic diathesis twenty-four months after diagnosis. This clinical case maybe represents an example of the chronic form of mast cell leukemia, described as unpredictable disease, in which the serum total tryptase level has confirmed itself as a reliable marker of mast cells burden regardless of the presence of other signs or symptoms.

Focal nodular hyperplasia after busulfan treatment.

The case of a 48-year-old woman in whom focal nodular hyperplasia of the liver developed after busulfan therapy was administered for essential thrombocytosis is described. Focal nodular hyperplasia is a reactive disorder related to a circulation disorder. The close temporal relation between the haematological disease, busulfan treatment and the appearance of hyperplastic diseases of the liver in our patient supports the possibility that the association of the events might not be casual.

Occult colon cancer in a patient with an unexplained episode of pulmonary embolism.

The association between venous thromboembolism and cancer has been widely documented and the main factor responsible for cancer-induced venous thromboembolism is considered mostly linked to a hypercoagulation state induced by the cancer itself. There is no consensus on investigative strategies for occult cancer in a patient with a thrombophilic condition. We report a patient who manifested an isolated episode of pulmonary embolism without specific evident sources of venous thromboembolism. The routine clinical and laboratory work-up to detect an occult cancer did not reveal any malignancy. A history of duodenal ulcer in association with a recent slight alteration in bowel habits led us to perform an esophagogastroduodenoscopy which was negative for malignancy, and a barium enema followed by colonoscopy, which revealed the presence of a tumor limited to the large intestine. An unexplained clinically evident hypercoagulation state, even in the presence of mild clinical symptoms, needs more thorough diagnostic strategies when simple methods of screening for occult cancer are negative.