Atypical myeloproliferative disorders in adults

Urgent Coronary Artery Bypass Surgery in a Patient with Postinfarction Angina and Active Myelomonocytic Leukaemia

Chronic myelomonocytic leukaemia (CMML) is a myelodysplastic/myeloproliferative neoplasm affecting the production and differentiation of the monocyte cell lineage. Cardiac surgery in the context of CMML poses challenges that are not routinely encountered. This is the first reported case in the literature of a patient with active CMML undergoing urgent on-pump coronary artery bypass grafting. A 68-year-old Caucasian man with a history of hypertension, hyperlipidaemia, hypothyroidism, and hypercholesterolaemia, who had been diagnosed by the haematologists with CMML a few months earlier but had remained untreated, underwent urgent surgical coronary revascularisation because of postinfarction angina following a non-ST elevation myocardial infarction associated with troponin I rise. The patient had fulminant postoperative myelomonocytic leukaemoid reaction, with a clinical picture of severe systemic inflammatory response syndrome and multiple organ dysfunction syndrome. This led to extensive vasodilation and heart failure that resulted in the death of the patient. Various authors have suggested different techniques and treatment options, each attempting to mitigate the effect of the postoperative inflammatory response. However, this is a high-risk endeavour with a myriad of inflammatory signals mobilised into action because of the surgical insult. Off-pump surgery or preoperative pharmacological attenuation of CMML activity might have dampened this response and resulted in a positive outcome for the patient.

Chronic Eosinophilic Leukemia Presenting Predominantly with Cutaneous Manifestations

A 37-year-old male presented with severe oral and genital mucosal ulcers, lichenoid eruption and twenty-nail dystrophy. Systemic examination was normal, except for anemia. On investigations, he was found to have persistently elevated peripheral eosinophilia, absolute eosinophil count >5000/mm³, bone marrow showing increased eosinophilic precursors, and infiltration by atypical cells. The serum vitamin B12 levels were grossly elevated, and Philadelphia chromosome study was negative. Thus, a diagnosis of chronic eosinophilic leukemia was made. The patient showed excellent response to imatinib mesylate. We are reporting a rare type of leukemia presenting with predominantly cutaneous manifestations.

World health organization classification, evaluation, and genetics of the myeloproliferative neoplasm variants

There is no single category in the fourth edition (2008) of the World Health Organization (WHO) classification of myeloid neoplasms that encompasses all of the diseases referred to by some authors as the myeloproliferative neoplasm (MPN) "variants." Instead, they are considered as distinct entities and are distributed among various subgroups of myeloid neoplasms in the classification scheme. These relatively uncommon neoplasms do not meet the criteria for any so-called "classical" MPN (chronic myelogenous leukemia, polycythemia vera, primary myelofibrosis, or essential thrombocythemia) and, although some exhibit myelodysplasia, none meets the criteria for any myelodysplastic syndrome (MDS). They are a diverse group of neoplasms ranging from fairly well-characterized disorders such as chronic myelomonocytic leukemia to rare and thus poorly characterized disorders such as chronic neutrophilic leukemia. Recently, however, there has been a surge of information regarding the genetic infrastructure of neoplastic cells in the MPN variants, allowing some to be molecularly defined. Nevertheless, in most cases, correlation of clinical, genetic, and morphologic findings is required for diagnosis and classification. The fourth edition of the WHO classification provides a framework to incorporate those neoplasms in which a genetic abnormality is a major defining criterion of the disease, such as those associated with eosinophilia and abnormalities of PDGFRA, PDGFRB, and FGFR1, as well as for those in which no specific genetic defect has yet been discovered and which remain clinically and pathologically defined. An understanding of the clinical, morphologic, and genetic features of the MPN variants will facilitate their diagnosis.