Challenging and unusual cases: Case 1. Simultaneous presentation of acute myelogenous leukemia and myocardial infarction

Diffuse periostitis as the primary presenting radiological finding in an AML patient with disease relapse

Acute myelogenous leukemia is a hematologic malignancy defined by the presence of myeloid blasts causing bone marrow infiltration. Evaluation and workup of acute myelogenous leukemia is based on comprehensive medical history, physical examination, laboratory evaluation, and bone marrow sampling. Magnetic resonance (MR) imaging is the study of choice in the evaluation of this disease including the initial evaluation, treatment follow-up, and complications. Herein, we report a case of relapse of the acute myelogenic leukemia in an adult patient who presented with diffuse periostitis in his lower extremities diagnosed on MR imaging and confirmed on Technetium bone scan, which also showed periostitis along the bilateral humeri. To our knowledge, this was not previously reported in the English literature.

ST-elevation myocardial infarction and myelodysplastic syndrome with acute myeloid leukemia transformation

Acute myocardial infarction and acute myeloid leukemia are rarely reported as concomitant conditions. The management of ST-elevation myocardial infarction (STEMI) in patients who have acute myeloid leukemia is challenging: the leukemia-related thrombocytopenia, platelet dysfunction, and systemic coagulopathy increase the risk of bleeding, and the administration of thrombolytic agents can be fatal. We report the case of a 76-year-old man who presented emergently with STEMI, myelodysplastic syndrome, and newly recognized acute myeloid leukemia transformation. Standard antiplatelet and anticoagulation therapy were contraindicated by the patient's thrombocytopenia and by his reported ecchymosis and gingival bleeding upon admission. He declined cardiac catheterization, was provided palliative care, and died 2 hours after hospital admission. We searched the English-language medical literature, found 8 relevant reports, and determined that the prognosis for patients with concomitant STEMI and acute myeloid leukemia is clearly worse than that for either individual condition. No guidelines exist to direct the management of STEMI and concomitant acute myeloid leukemia. In 2 reports, dual antiplatelet therapy, anticoagulation, and drug-eluting stent implantation were used without an increased risk of bleeding in the short term, even in the presence of thrombocytopenia. However, we think that a more conservative approach--balloon angioplasty with the provisional use of bare-metal stents--might be safer. Simultaneous chemotherapy for the acute myeloid leukemia is crucial. Older age seems to be a major risk factor: patients too frail for emergent treatment can die within hours or days.

Acute myeloid leukemia associated with acute myocardial infarction and dural sinus thrombosis: the possible role of leukemia-related hyperhomocysteinemia

The association of acute myeloid leukemia (AML) and acute myocardial infarction (AMI) is rare. We encountered a 40-year-old female with inferior wall myocardial infarction that occurred simultaneously with the diagnosis of AML. She developed subsequent dural sinus thrombosis during chemotherapy for AML. The screen for thrombophilia revealed that she had hyperhomocysteinemia. In the English literature, only 4 cases have been reported previously. Remission induction was not affected by the occurrence of AMI, although anthracyclines were avoided in all cases. In the absence of conventional risk factors for coronary artery disease, AMI can be related to leukemia per se and the role of homocysteine is worth further investigation.

Coexistence of gastrointestinal stromal tumors with other neoplasms

BACKGROUND

The purpose of this study was to assess the prevalence of other neoplasms in patients with gastrointestinal stromal tumors (GISTs) and to compare clinical and histopathological data in patients with a GIST and accompanying neoplasms and in patients with GIST only.

METHODS

The analysis encompassed 82 patients with a GIST from among 330 300 patients whose surgical specimens, biopsies, and autopsies were evaluated between January 1989 and June 2006. A subgroup of patients with other types of neoplasms was selected.

RESULTS

Other neoplasms in patients with a GIST were diagnosed in 22 of the 82 (26.8%) patients. The most common accompanying neoplasms were colorectal (nine cases) and gastric (four cases) adenocarcinoma, as well as pancreatic adenocarcinoma (three cases). There was a tendency toward more common localization of a GIST in the small intestine in patients with other neoplasms than in patients with a GIST alone (P < 0.09). Tumors with very low risk of aggressive behavior were more frequent in patients with a GIST accompanied by other neoplasms than in the other group (P < 0.05). No phenotypic differences in GIST cells were found between the two groups.

CONCLUSIONS

In almost 27% of the study population, GISTs coexisted with other neoplasms. A greater proportion of patients with a GIST localized in the small intestine and/or characterized by a very low risk of aggressive behavior and accompanying other neoplasms, compared with a GIST alone, most likely reflects the fact that in the first group, GISTs tended to be an incidental finding during surgery. The results were affected by patient selection and the type of tissue material available.

Incidental localized (solitary) mediastinal malignant mesothelioma

Primary mediastinal mesotheliomas are rare tumours. The mesothelial lining cells of the the pericardium are suggested as the most probable cells of origin. Most of these tumours appear either as a diffuse or nodular thickening of the pericardium that encase and even invade the heart. Localized mediastinal mesotheliomas are distinctly uncommon. We report the imaging findings of a solitary malignant mediastinal mesothelioma that presented mainly as a cystic anterior mediastinal mass. On chest radiography, the tumour appeared as a right paramediastinal soft tissue mass located adjacent to the right middle and lower lobes. On CT, a large, well-circumscribed, right anterior mediastinal mass with a central zone of fluid attenuation was observed. This mass had a thin, smooth wall of uniform thickness as well as a small component that demonstrated soft tissue attenuation. There was no plane of separation between the tumour and aorta/superior vena cava. At surgery the tumour could be dissected easily free from the pericardium and great vessels and it was removed totally. Histopathological examination of the tumour revealed a malignant epitheloid mesothelioma.